Publication date: Available online 13 February 2018
Source:Radiotherapy and Oncology
Author(s): Gerd Heilemann, Lukas Fetty, Matthias Blaickner, Nicole Nesvacil, Martin Zehetmayer, Dietmar Georg, Roman Dunavoelgyi
Background and purposeTo evaluate the retina dose as a risk factor associated with loss of visual acuity (VA) in 106Ru plaque brachytherapy.Material/methods45 patients receiving 106Ru plaques brachytherapy (median follow-up 29.5 months) were included in this study. An in-house developed treatment planning system with Monte Carlo based dose calculation was used to perform treatment planning and dose calculation. Risk factors associated with loss of VA were evaluated using the Cox proportional hazards models, Kaplan–Meier estimates and Pearson correlation coefficients.ResultsA significant correlation was found between VA loss and mean (r = 0.49, p = 0.001) and near maximum (r = 0.47, p = 0.001) retina dose D2% and tumor basal diameter (r = 0.50, p < 0.001). The Kaplan–Meier and Cox proportional hazards model yielded a significantly higher risk for VA loss (>0.3Snellen) for patients receiving a maximum dose of >500 Gy (p = 0.002). A Cox multivariate analysis including the macula dose (p = 0.237) and basal diameter (p = 0.791) showed that a high maximum retinal dose is the best risk factor (p = 0.013) for VA loss.ConclusionThe study showed that retina dose (D2% and Dmean) is a suitable predictor for VA loss.
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Τρίτη 13 Φεβρουαρίου 2018
Retina dose as a predictor for visual acuity loss in 106Ru eye plaque brachytherapy of uveal melanomas
Improved cost-effectiveness of short-course radiotherapy in elderly and/or frail patients with glioblastoma
Publication date: Available online 13 February 2018
Source:Radiotherapy and Oncology
Author(s): Sunita Ghosh, Sarah Baker, Douglas Guedes de Castro, Lucyna Kepka, Narendra Kumar, Valery Sinaika, Juliana Matiello, Darejan Lomidze, Katarzyna Dyttus-Cebulok, Eduardo Rosenblatt, Elena Fidarova, Wilson Roa
Background and purposeShort-course radiotherapy (25 Gy in five fractions) was recently shown in a randomized phase III trial to be non-inferior to 40 Gy in 15 fractions in elderly and/or frail patients with glioblastoma multiforme. This study compared the cost-effectiveness of the two regimens.Material and methodsThe direct unit costs of imaging, radiotherapy (RT), and dexamethasone were collected from the five primary contributing countries to the trial, constituting the data of 88% of all patients. Effectiveness was measured by the restricted mean overall survival (RMOS) and progression free survival (RMPFS). The incremental cost-effectiveness ratio (ICER) was calculated. Indirect costs were also estimated for comparison.ResultsThe median OSs for the short-course and commonly used RTs were 8.2 (95% confidence interval [CI] 6.1–10.3) and 7.7 (95% CI 5.5–9.9) months, respectively (log rank p = 0.340). Median PFSs were also not different (p = 0.686). The differences in the RMOS and the ICER, however, were +0.11 life-years and -$3062 United States dollars (USD) per life-year gained, respectively. The differences in the RMPFS and the ICER were +0.02 PFS and -$17,693 USD, respectively.ConclusionThe ICER of -$3062 per life-year gained and -$17,693 per PFS gained indicates that the short-course RT is less costly compared to the longer RT regimen.
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Diagnostic Accuracy of Amino Acid and FDG-PET in Differentiating Brain Metastasis Recurrence from Radionecrosis after Radiotherapy: A Systematic Review and Meta-Analysis [ADULT BRAIN]
BACKGROUND:
Current studies that analyze the usefulness of amino acid and FDG-PET in distinguishing brain metastasis recurrence and radionecrosis after radiation therapy are limited by small cohort size.
PURPOSE:Our aim was to assess the diagnostic accuracy of amino acid and FDG-PET in differentiating brain metastasis recurrence from radionecrosis after radiation therapy.
DATA SOURCES:Studies were retrieved from PubMed, Embase, and the Cochrane Library.
STUDY SELECTION:Fifteen studies were included from the literature. Each study used PET to differentiate radiation necrosis from tumor recurrence in contrast-enhancing lesions on follow-up brain MR imaging after treating brain metastasis with radiation therapy.
DATA ANALYSIS:Data were analyzed with a bivariate random-effects model. Sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio were pooled, and a summary receiver operating characteristic curve was fit to the data.
DATA SYNTHESIS:The overall pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio of PET were 0.85, 0.88, 7.0, 0.17, and 40, respectively. The area under the receiver operating characteristic curve was 0.93. On subgroup analysis of different tracers, amino acid and FDG-PET had similar diagnostic accuracy. Meta-regression analysis demonstrated that the method of quantification based on patient, lesion, or PET scan (based on lesion versus not, P = .07) contributed to the heterogeneity.
LIMITATIONS:Our study was limited by small sample size, and 60% of the included studies were of retrospective design.
CONCLUSIONS:Amino acid and FDG-PET had good diagnostic accuracy in differentiating brain metastasis recurrence from radionecrosis after radiation therapy.
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Improved cost-effectiveness of short-course radiotherapy in elderly and/or frail patients with glioblastoma
Short-course radiotherapy (25 Gy in five fractions) was recently shown in a randomized phase III trial to be non-inferior to 40 Gy in 15 fractions in elderly and/or frail patients with glioblastoma multiforme. This study compared the cost-effectiveness of the two regimens.
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Retina dose as a predictor for visual acuity loss in 106Ru eye plaque brachytherapy of uveal melanomas
To evaluate the retina dose as a risk factor associated with loss of visual acuity (VA) in 106Ru plaque brachytherapy.
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Dynamic Diffuse Optical Tomography for Monitoring Neoadjuvant Chemotherapy in Patients with Breast Cancer.
Dynamic Diffuse Optical Tomography for Monitoring Neoadjuvant Chemotherapy in Patients with Breast Cancer.
Radiology. 2018 Feb 12;:161041
Authors: Gunther JE, Lim EA, Kim HK, Flexman M, Altoé M, Campbell JA, Hibshoosh H, Crew KD, Kalinsky K, Hershman DL, Hielscher AH
Abstract
Purpose To identify dynamic optical imaging features that associate with the degree of pathologic response in patients with breast cancer during neoadjuvant chemotherapy (NAC). Materials and Methods Of 40 patients with breast cancer who participated in a longitudinal study between June 2011 and March 2016, 34 completed the study. There were 13 patients who obtained a pathologic complete response (pCR) and 21 patients who did not obtain a pCR. Imaging data from six subjects were excluded from the study because either the patients dropped out of the study before it was finished or there was an instrumentation malfunction. Two weeks into the treatment regimen, three-dimensional images of both breasts during a breath hold were acquired by using dynamic diffuse optical tomography. Features from the breath-hold traces were used to distinguish between response groups. Receiver operating characteristic (ROC) curves and sensitivity analysis were used to determine the degree of association with 5-month treatment outcome. Results An ROC curve analysis showed that this method could identify patients with a pCR with a positive predictive value of 70.6% (12 of 17), a negative predictive value of 94.1% (16 of 17), a sensitivity of 92.3% (12 of 13), a specificity of 76.2% (16 of 21), and an area under the ROC curve of 0.85. Conclusion Several dynamic optical imaging features obtained within 2 weeks of NAC initiation were identified that showed statistically significant differences between patients with pCR and patients without pCR as determined 5 months after treatment initiation. If confirmed in a larger cohort prospective study, these dynamic imaging features may be used to predict treatment outcome as early as 2 weeks after treatment initiation. © RSNA, 2018 Online supplemental material is available for this article.
PMID: 29431574 [PubMed - as supplied by publisher]
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Evaluation of therapeutic effects of 125I particles brachytherapy for recurrent bladder cancer.
Evaluation of therapeutic effects of 125I particles brachytherapy for recurrent bladder cancer.
Oncol Lett. 2018 Mar;15(3):3453-3457
Authors: Zhou YM, Feng X, Zhou BC, Fan YF, Huang YL
Abstract
The aim of the present study was to evaluate the clinical value of 125I particles implantation in the treatment of recurrent bladder cancer. The study is a retrospective analysis of 32 patients with recurrent bladder cancer treated between May 2010 and January 2010. Of these, 16 cases (chemotherapy group) received conventional chemotherapy. A total of 16 patients (125I group) received radiotherapy with 125I particles, followed by conventional chemotherapy. By guidance of B ultrasound, 125I radioactive particles were implanted. All 32 patients were relieved after treatment, and the tumors were significantly reduced after 2 months. However, the tumors in the 125I group were significantly smaller than those in the chemotherapy group (P<0.05). The patients were followed-up for 1 year and no recurrence was found. Additionally, no complications occurred. Compared with the chemotherapy group, the tumor volume of the 125I group was significantly reduced (P<0.05). The disease-free survival and 5-year survival rates of the patients in the follow-up showed that the disease-free survival and 5-year survival rates of the patients in 125I group were significantly improved compared to those in the chemotherapy group. Therefore, the results have shown that 125I radioactive particles in the treatment of bladder cancer improve the symptoms of patients with bladder cancer in the short term, and continuously kill residual tumor and prevent recurrence.
PMID: 29435083 [PubMed]
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The protective effect of melatonin on sperm quality in rat after radioiodine treatment.
The protective effect of melatonin on sperm quality in rat after radioiodine treatment.
Andrologia. 2018 Feb 11;:
Authors: Cebi Sen C, Yumusak N, Atilgan HI, Sadic M, Koca G, Korkmaz M
Abstract
This study was designed to investigate the potential radioprotective impact of melatonin on the testicular tissue and sperm quality in rat given radioactive iodine (RAI) therapy. Thirty-six male Wistar albino rats were randomly divided into three groups as untreated control (Group 1); oral radioiodine group (RAI, 111 MBq, administrated rats); and RAI+melatonin group (oral radioiodine and intraperitoneal 12 mg/kg/day melatonin, starting 2 days before and continuing for 1 week after oral RAI administration). Twenty-four hours after the injection of the last melatonin dose, blood samples were taken for hormone analyses and the determination of the total antioxidant capacity. Sperm samples taken from the cauda epididymis were examined for spermatological parameters. Tissue samples taken from the rat testes were stained by TUNEL assay and with haematoxylin-eosin to detect apoptosis and histological alterations. It was demonstrated a significant decrease in epididymal spermatozoa viability and motility in all of the treatment groups, in comparison with the control group (p < .001). A significant decrease was also detected in sperm DNA fragmentation, follicle-stimulating hormone (FSH) level and the index of apoptotic germ cells in the RAI+melatonin group when compared to the radioiodine group. It was concluded that melatonin prevents the adverse affects of RAI on apoptosis and spermatozoa quality.
PMID: 29430687 [PubMed - as supplied by publisher]
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Calibration setting numbers for dose calibrators for the PET isotopes (52)Mn, (64)Cu, (76)Br, (86)Y, (89)Zr, (124)I.
Related Articles |
Calibration setting numbers for dose calibrators for the PET isotopes (52)Mn, (64)Cu, (76)Br, (86)Y, (89)Zr, (124)I.
Appl Radiat Isot. 2016 07;113:89-95
Authors: Wooten AL, Lewis BC, Szatkowski DJ, Sultan DH, Abdin KI, Voller TF, Liu Y, Lapi SE
Abstract
For PET radionuclides, the radioactivity of a sample can be conveniently measured by a dose calibrator. These devices depend on a "calibration setting number", but many recommended settings from manuals were interpolated based on standard sources of other radionuclide(s). We conducted HPGe gamma-ray spectroscopy, resulting in a reference for determining settings in two types of vessels containing one of several PET radionuclides. Our results reiterate the notion that in-house, experimental calibrations are recommended for different radionuclides and vessels.
PMID: 27152914 [PubMed - indexed for MEDLINE]
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Verification of I-125 brachytherapy source strength for use in radioactive seed localization procedures.
Related Articles |
Verification of I-125 brachytherapy source strength for use in radioactive seed localization procedures.
Appl Radiat Isot. 2016 06;112:62-8
Authors: Metyko J, Erwin W, Landsberger S
Abstract
A general-purpose nuclear medicine dose calibrator was assessed as a potential replacement for a dedicated air-communicating well-type ionization chamber (brachytherapy source strength verification instrument) for (125)I seed source strength verification for radioactive seed localization, where less stringent accuracy tolerances may be acceptable. The accuracy, precision and reproducibility of the dose calibrator were measured and compared to regulatory requirements. The results of this work indicate that a dose calibrator can be used for (125)I seed source strength verification for radioactive seed localization.
PMID: 27015651 [PubMed - indexed for MEDLINE]
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Optic Nerve Measurement on MRI in the Pediatric Population: Normative Values and Correlations [PEDIATRICS]
BACKGROUND AND PURPOSE:
Few articles in the literature have looked at the diameter of the optic nerve on MR imaging, especially in children, in whom observations are subjective and no normative data exist. The aim of this study was to establish a data base for optic nerve diameter measurements on MR imaging in the pediatric population.
MATERIALS AND METHODS:This was a retrospective study on the MR imaging of pediatric subjects (younger than 18 years of age) at the Department of Diagnostic Radiology at the American University of Beirut Medical Center, Beirut, Lebanon. The optic nerve measurements were obtained by 3 raters on axial and coronal sections at 3 mm (retrobulbar) and 7 mm (intraorbital) posterior to the lamina cribrosa.
RESULTS:Of 211 scans of patients (422 optic nerves), 377 optic nerves were measured and included. Ninety-four patients were female (45%) and the median age at MR imaging was 8.6 years (interquartile range, 3.9–13.3 years). Optic nerves were divided into 5 age groups: 0–6 months (n = 18), 6 months–2 years (n = 44), 2–6 years (n = 86), 6–12 years (n = 120), and 12–18 years (n = 109). An increase in optic nerve diameter was observed with age, especially in the first 2 years of life. Measurements did not differ with eye laterality or sex.
CONCLUSIONS:We report normative values of optic nerve diameter measured on MR imaging in children from birth to 18 years of age. A rapid increase in optic nerve diameter was demonstrated during the first 2 years of life, followed by a slower increase. This was independent of sex or eye laterality.
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Multiparametric Imaging Improves Confidence in the Diagnosis of Multinodular and Vacuolating Neuronal Tumor of the Cerebrum [LETTERS]
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Leukoaraiosis Attenuates Diagnostic Accuracy of Large-Vessel Occlusion Scales [INTERVENTIONAL]
BACKGROUND AND PURPOSE:
Prehospital stroke scales may help identify patients likely to have large-vessel occlusion to facilitate rapid triage to thrombectomy-capable stroke centers. Scale misclassification may result in inaccurate decisions and possible harm. Pre-existing leukoaraiosis has been shown to attenuate the association between deficit type and stroke severity. We sought to determine whether leukoaraiosis affects the predictive ability of 5 commonly used large-vessel occlusion scales.
MATERIALS AND METHODS:We retrospectively analyzed 274 consecutive patients with stroke with available brain MR imaging and vessel imaging. We used the following large-vessel occlusion scales: the 3-Item Stroke Scale; Field Assessment Stroke Triage for Emergency Destination; Rapid Arterial Occlusion Evaluation; Vision, Aphasia, Neglect score; and Cincinnati Prehospital Stroke Severity Scale. For diagnostic scale accuracy, we assessed sensitivity, specificity, positive predictive value, negative predictive value, and . Multivariable logistic regression was used to determine the predictive ability of the scales after adjustment for leukoaraiosis and potential confounders.
RESULTS:In unadjusted analyses, all scales predicted the presence of large-vessel occlusion (n = 46, P < .01 each), though diagnostic accuracy was attenuated among patients with moderate-to-severe leukoaraiosis. After adjustment, the Field Assessment Stroke Triage for Emergency Destination (OR = 3.2; 95% CI, 1.1–9.5; P = .033) and Rapid Arterial Occlusion Evaluation (OR = 3.7; 95% CI, 1.3–10.8; P = .015), but not the 3-Item Stroke Scale (OR = 5.4; 95% CI, 0.86–33.9; P = .073), Vision, Aphasia, Neglect score (OR = 2.5; 95% CI, 0.8–7.2), and Cincinnati Prehospital Stroke Severity Scale (OR = 2.8; 95% CI, 1.0–8.0), predicted large-vessel occlusion.
CONCLUSIONS:The diagnostic accuracy of the tested large-vessel occlusion scales was attenuated in the presence of moderate-to-severe leukoaraiosis. This information that may aid the design of future studies that require large-vessel occlusion scale screening of patients who are likely to have concomitant leukoaraiosis.
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Feasibility of Brain Atrophy Measurement in Clinical Routine without Prior Standardization of the MRI Protocol: Results from MS-MRIUS, a Longitudinal Observational, Multicenter Real-World Outcome Study in Patients with Relapsing-Remitting MS [ADULT BRAIN]
BACKGROUND AND PURPOSE:
Feasibility of brain atrophy measurement in patients with MS in clinical routine, without prior standardization of the MRI protocol, is unknown. Our aim was to investigate the feasibility of brain atrophy measurement in patients with MS in clinical routine.
MATERIALS AND METHODS:Multiple Sclerosis and Clinical Outcome and MR Imaging in the United States (MS-MRIUS) is a multicenter (33 sites), retrospective study that included patients with relapsing-remitting MS who began treatment with fingolimod. Brain MR imaging examinations previously acquired at the baseline and follow-up periods on 1.5T or 3T scanners with no prior standardization were used, to resemble a real-world situation. Brain atrophy outcomes included the percentage brain volume change measured by structural image evaluation with normalization of atrophy on 2D-T1-weighted imaging and 3D-T1WI and the percentage lateral ventricle volume change, measured by VIENA on 2D-T1WI and 3D-T1WI and NeuroSTREAM on T2-fluid-attenuated inversion recovery examinations.
RESULTS:A total of 590 patients, followed for 16 months, were included. There were 585 (99.2%) T2-FLAIR, 425 (72%) 2D-T1WI, and 166 (28.2%) 3D-T1WI longitudinal pairs of examinations available. Excluding MR imaging examinations with scanner changes, the analyses were available on 388 (65.8%) patients on T2-FLAIR for the percentage lateral ventricle volume change, 259 and 257 (43.9% and 43.6%, respectively) on 2D-T1WI for the percentage brain volume change and the percentage lateral ventricle volume change, and 110 (18.6%) on 3D-T1WI for the percentage brain volume change and percentage lateral ventricle volume change. The median annualized percentage brain volume change was –0.31% on 2D-T1WI and –0.38% on 3D-T1WI. The median annualized percentage lateral ventricle volume change was 0.95% on 2D-T1WI, 1.47% on 3D-T1WI, and 0.90% on T2-FLAIR.
CONCLUSIONS:Brain atrophy was more readily assessed by estimating the percentage lateral ventricle volume change on T2-FLAIR compared with the percentage brain volume change or percentage lateral ventricle volume change using 2D- or 3D-T1WI in this observational retrospective study. Although measurement of the percentage brain volume change on 3D-T1WI remains the criterion standard and should be encouraged in future prospective studies, T2-FLAIR–derived percentage lateral ventricle volume change may be a more feasible surrogate when historical or other practical constraints limit the availability of percentage brain volume change on 3D-T1WI.
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The Anesthesiologist, Rather Than the Anesthesia, May Influence the Outcomes following Stroke Thrombectomy [LETTERS]
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Intranasal Esthesioneuroblastoma: CT Patterns Aid in Preventing Routine Nasal Polypectomy [HEAD & NECK]
BACKGROUND AND PURPOSE:
Esthesioneuroblastoma is a neuroectodermal tumor that commonly arises in the nasal cavity olfactory recess and, when isolated to the intranasal cavity, can be indistinguishable from benign processes. Because lesional aggressiveness requires a more invasive operation for resection than polypectomy, patients with isolated intranasal lesions were studied to define distinguishing CT characteristics.
MATERIALS AND METHODS:Patients with intranasal esthesioneuroblastoma and controls without esthesioneuroblastoma with olfactory recess involvement were identified by using a report search tool. Studies demonstrating skull base invasion and/or intracranial extension were excluded. The imaging spectrum of these lesions was reviewed on both CT and MR imaging, and CT findings were compared with those of controls without esthesioneuroblastoma. Two blinded readers assessed subjects with esthesioneuroblastomas and controls without esthesioneuroblastoma and, using only CT criteria, rated their level of suspicion for esthesioneuroblastoma in each case.
RESULTS:Eight histologically proved cases of intranasal esthesioneuroblastoma were reviewed. All cases had CT demonstrating 3 main findings: 1) an intranasal polypoid lesion with its epicenter in a unilateral olfactory recess, 2) causing asymmetric olfactory recess widening, and 3) extending to the cribriform plate. Twelve patients with non-esthesioneuroblastoma diseases involving the olfactory recess were used as controls. Using these 3 esthesioneuroblastoma CT criteria, 2 blinded readers evaluating patients with esthesioneuroblastoma and controls had good diagnostic accuracy (area under the curve = 0.85 for reader one, 0.81 for reader 2) for predicting esthesioneuroblastoma.
CONCLUSIONS:Esthesioneuroblastoma can present as a well-marginated intranasal lesion that unilaterally widens the olfactory recess. CT patterns can help predict esthesioneuroblastoma, potentially preventing multiple operations by instigating the correct initial operative management.
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Economic Considerations in MR Imaging of Patients with Cardiac Devices [LETTERS]
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Clinical and Radiologic Characteristics of Deep Lumbosacral Dural Arteriovenous Fistulas [SPINE]
BACKGROUND AND PURPOSE:
Spinal dural arteriovenous fistulas located in the deep lumbosacral region are rare and the most difficult to diagnose among spinal dural arteriovenous fistulas located elsewhere in the spinal dura. Specific clinical and radiologic features of these fistulas are still inadequately reported and are the subject of this study.
MATERIALS AND METHODS:We retrospectively evaluated all data of patients with spinal dural arteriovenous fistulas treated and/or diagnosed in our institution between 1990 and 2017. Twenty patients with deep lumbosacral spinal dural arteriovenous fistulas were included in this study.
RESULTS:The most common neurologic findings at the time of admission were paraparesis (85%), sphincter dysfunction (70%), and sensory disturbances (20%). Medullary T2 hyperintensity and contrast enhancement were present in most cases. The filum vein and/or lumbar veins were dilated in 19/20 (95%) patients. Time-resolved contrast-enhanced dynamic MRA indicated a spinal dural arteriovenous fistula at or below the L5 vertebral level in 7/8 (88%) patients who received time-resolved contrast-enhanced dynamic MRA before DSA. A bilateral arterial supply of the fistula was detected via DSA in 5 (25%) patients.
CONCLUSIONS:Clinical symptoms caused by deep lumbosacral spinal dural arteriovenous fistulas are comparable with those of spinal dural arteriovenous fistulas at other locations. Medullary congestion in association with an enlargement of the filum vein or other lumbar radicular veins is a characteristic finding in these patients. Spinal time-resolved contrast-enhanced dynamic MRA facilitates the detection of the drainage vein and helps to localize deep lumbosacral-located fistulas with a high sensitivity before DSA. Definite detection of these fistulas remains challenging and requires sufficient visualization of the fistula-supplying arteries and draining veins by conventional spinal angiography.
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Combining Quantitative Susceptibility Mapping with Automatic Zero Reference (QSM0) and Myelin Water Fraction Imaging to Quantify Iron-Related Myelin Damage in Chronic Active MS Lesions [ADULT BRAIN]
BACKGROUND AND PURPOSE:
A hyperintense rim on susceptibility in chronic MS lesions is consistent with iron deposition, and the purpose of this study was to quantify iron-related myelin damage within these lesions as compared with those without rim.
MATERIALS AND METHODS:Forty-six patients had 2 longitudinal quantitative susceptibility mapping with automatic zero reference scans with a mean interval of 28.9 ± 11.4 months. Myelin water fraction mapping by using fast acquisition with spiral trajectory and T2 prep was obtained at the second time point to measure myelin damage. Mixed-effects models were used to assess lesion quantitative susceptibility mapping and myelin water fraction values.
RESULTS:Quantitative susceptibility mapping scans were on average 6.8 parts per billion higher in 116 rim-positive lesions compared with 441 rim-negative lesions (P < .001). All rim-positive lesions retained a hyperintense rim over time, with increasing quantitative susceptibility mapping values of both the rim and core regions (P < .001). Quantitative susceptibility mapping scans and myelin water fraction in rim-positive lesions decreased from rim to core, which is consistent with rim iron deposition. Whole lesion myelin water fractions for rim-positive and rim-negative lesions were 0.055 ± 0.07 and 0.066 ± 0.04, respectively. In the mixed-effects model, rim-positive lesions had on average 0.01 lower myelin water fraction compared with rim-negative lesions (P < .001). The volume of the rim at the initial quantitative susceptibility mapping scan was negatively associated with follow-up myelin water fraction (P < .01).
CONCLUSIONS:Quantitative susceptibility mapping rim-positive lesions maintained a hyperintense rim, increased in susceptibility, and had more myelin damage compared with rim-negative lesions. Our results are consistent with the identification of chronic active MS lesions and may provide a target for therapeutic interventions to reduce myelin damage.
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Feasibility of Permanent Stenting with Solitaire FR as a Rescue Treatment for the Reperfusion of Acute Intracranial Artery Occlusion [INTERVENTIONAL]
BACKGROUND AND PURPOSE:
The Solitaire FR can be used not only as a tool for mechanical thrombectomy but also as a detachable permanent stent. Our aim was to assess the feasibility and safety of permanent stent placement with the Solitaire FR compared with other self-expanding stents for intracranial artery recanalization for acute ischemic stroke.
MATERIALS AND METHODS:From January 2011 through January 2016, we retrospectively selected 2979 patients with acute ischemic stroke. Among them, 27 patients who underwent permanent stent placement (13 patients with the Solitaire FR [Solitaire group] and 14 patients with other self-expanding stents [other stent group]) were enrolled. The postprocedural modified TICI grade and angiographic and clinical outcomes were assessed. The safety and efficacy of permanent stent placement of the Solitaire FR for acute large-artery occlusion were evaluated.
RESULTS:Stent placement was successful in all cases. Modified TICI 2b–3 reperfusion was noted in 84.6% of the Solitaire group and in 78.6% of the other stent group. Procedural time was significantly shorter in the Solitaire group than in the other stent group (P = .022). Shorter procedural time was correlated with favorable outcome ( = 0.46, P = .035). No significant differences were found in the modified TICI grade, NIHSS score, mRS, and hemorrhagic transformation rate between the 2 groups. The acute in-stent thrombosis rate at discharge was significantly lower when a glycoprotein IIb/IIIa inhibitor was injected during the procedure (P = .013).
CONCLUSIONS:Permanent stent placement with the Solitaire FR compared with other self-expanding stents appears to be feasible and safe as a rescue tool for refractory intra-arterial therapy.
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Radiomics in Brain Tumor: Image Assessment, Quantitative Feature Descriptors, and Machine-Learning Approaches [ADULT BRAIN]
SUMMARY:
Radiomics describes a broad set of computational methods that extract quantitative features from radiographic images. The resulting features can be used to inform imaging diagnosis, prognosis, and therapy response in oncology. However, major challenges remain for methodologic developments to optimize feature extraction and provide rapid information flow in clinical settings. Equally important, to be clinically useful, predictive radiomic properties must be clearly linked to meaningful biologic characteristics and qualitative imaging properties familiar to radiologists. Here we use a cross-disciplinary approach to highlight studies in radiomics. We review brain tumor radiologic studies (eg, imaging interpretation) through computational models (eg, computer vision and machine learning) that provide novel clinical insights. We outline current quantitative image feature extraction and prediction strategies with different levels of available clinical classes for supporting clinical decision-making. We further discuss machine-learning challenges and data opportunities to advance radiomic studies.
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Semiautomated Middle Ear Volume Measurement as a Predictor of Postsurgical Outcomes for Congenital Aural Atresia [HEAD & NECK]
BACKGROUND AND PURPOSE:
Middle ear space is one of the most important components of the Jahrsdoerfer grading system (J-score), which is used to determine surgical candidacy for congenital aural atresia. The purpose of this study was to introduce a semiautomated method for measuring middle ear volume and determine whether middle ear volume, either alone or in combination with the J-score, can be used to predict early postoperative audiometric outcomes.
MATERIALS AND METHODS:A retrospective analysis was conducted of 18 patients who underwent an operation for unilateral congenital aural atresia at our institution. Using the Livewire Segmentation tool in the Carestream Vue PACS, we segmented middle ear volumes using a semiautomated method for all atretic and contralateral normal ears on preoperative high-resolution CT imaging. Postsurgical audiometric outcome data were then analyzed in the context of these middle ear volumes.
RESULTS:Atretic middle ear volumes were significantly smaller than those in contralateral normal ears (P < .001). Patients with atretic middle ear volumes of >305 mm3 had significantly better postoperative pure tone average and speech reception thresholds than those with atretic ears below this threshold volume (P = .01 and P = .006, respectively). Atretic middle ear volume incorporated into the J-score offered the best association with normal postoperative hearing (speech reception threshold ≤ 30 dB; OR = 37.8, P = .01).
CONCLUSIONS:Middle ear volume, calculated in a semiautomated fashion, is predictive of postsurgical audiometric outcomes, both independently and in combination with the conventional J-score.
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John Nash and the Organization of Stroke Care [research-article]
SUMMARY:
The concept of Nash equilibrium, developed by John Forbes Nash Jr, states that an equilibrium in noncooperative games is reached when each player takes the best action for himself or herself, taking into account the actions of the other players. We apply this concept to the provision of endovascular thrombectomy in the treatment of acute ischemic stroke and suggest that collaboration among hospitals in a health care jurisdiction could result in practices such as shared call pools for neurointervention teams, leading to better patient care through streamlined systems.
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Temporal Lobe Malformations in Achondroplasia: Expanding the Brain Imaging Phenotype Associated with FGFR3-Related Skeletal Dysplasias [PEDIATRICS]
SUMMARY:
Thanatophoric dysplasia, achondroplasia, and hypochondroplasia belong to the fibroblast growth factor receptor 3 (FGFR3) group of genetic skeletal disorders. Temporal lobe abnormalities have been documented in thanatophoric dysplasia and hypochondroplasia, and in 1 case of achondroplasia. We retrospectively identified 13 children with achondroplasia who underwent MR imaging of the brain between 2002 and 2015. All children demonstrated a deep transverse temporal sulcus on MR imaging. Further common neuroimaging findings were incomplete hippocampal rotation (12 children), oversulcation of the mesial temporal lobe (11 children), loss of gray-white matter differentiation of the mesial temporal lobe (5 children), and a triangular shape of the temporal horn (6 children). These appearances are very similar to those described in hypochondroplasia, strengthening the association of temporal lobe malformations in FGFR3-associated skeletal dysplasias.
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MR Perfusion to Determine the Status of Collaterals in Patients with Acute Ischemic Stroke: A Look Beyond Time Maps [ADULT BRAIN]
BACKGROUND AND PURPOSE:
Patients with acute stroke with robust collateral flow have better clinical outcomes and may benefit from endovascular treatment throughout an extended time window. Using a multiparametric approach, we aimed to identify MR perfusion parameters that can represent the extent of collaterals, approximating DSA.
MATERIALS AND METHODS:Patients with anterior circulation proximal arterial occlusion who had baseline MR perfusion and DSA were evaluated. The volume of arterial tissue delay (ATD) at thresholds of 2–6 seconds (ATD2–6 seconds) and >6 seconds (ATD>6 seconds) in addition to corresponding values of normalized CBV and CBF was calculated using VOI analysis. The association of MR perfusion parameters and the status of collaterals on DSA were assessed by multivariate analyses. Receiver operating characteristic analysis was performed.
RESULTS:Of 108 patients reviewed, 39 met our inclusion criteria. On DSA, 22/39 (56%) patients had good collaterals. Patients with good collaterals had significantly smaller baseline and final infarct volumes, smaller volumes of severe hypoperfusion (ATD>6 seconds), larger volumes of moderate hypoperfusion (ATD2–6 seconds), and higher relative CBF and relative CBV values than patients with insufficient collaterals. Combining the 2 parameters into a Perfusion Collateral Index (volume of ATD2–6 secondsx relative CBV2–6 seconds) yielded the highest accuracy for predicting collateral status: At a threshold of 61.7, this index identified 15/17 (88%) patients with insufficient collaterals and 22/22 (100%) patients with good collaterals, for an overall accuracy of 94.1%.
CONCLUSIONS:The Perfusion Collateral Index can predict the baseline collateral status with 94% diagnostic accuracy compared with DSA.
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Carotid Artery Wall Imaging: Perspective and Guidelines from the ASNR Vessel Wall Imaging Study Group and Expert Consensus Recommendations of the American Society of Neuroradiology [EXTRACRANIAL VASCULAR]
SUMMARY:
Identification of carotid artery atherosclerosis is conventionally based on measurements of luminal stenosis and surface irregularities using in vivo imaging techniques including sonography, CT and MR angiography, and digital subtraction angiography. However, histopathologic studies demonstrate considerable differences between plaques with identical degrees of stenosis and indicate that certain plaque features are associated with increased risk for ischemic events. The ability to look beyond the lumen using highly developed vessel wall imaging methods to identify plaque vulnerable to disruption has prompted an active debate as to whether a paradigm shift is needed to move away from relying on measurements of luminal stenosis for gauging the risk of ischemic injury. Further evaluation in randomized clinical trials will help to better define the exact role of plaque imaging in clinical decision-making. However, current carotid vessel wall imaging techniques can be informative. The goal of this article is to present the perspective of the ASNR Vessel Wall Imaging Study Group as it relates to the current status of arterial wall imaging in carotid artery disease.
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On the Reproducibility of Inversion Recovery Intravoxel Incoherent Motion Imaging in Cerebrovascular Disease [ADULT BRAIN]
BACKGROUND AND PURPOSE:
Intravoxel incoherent motion imaging can measure both microvascular and parenchymal abnormalities simultaneously. The contamination of CSF signal can be suppressed using inversion recovery preparation. The clinical feasibility of inversion recovery–intravoxel incoherent motion imaging was investigated in patients with cerebrovascular disease by studying its reproducibility.
MATERIALS AND METHODS:Sixteen patients with cerebrovascular disease (66 ± 8 years of age) underwent inversion recovery–intravoxel incoherent motion imaging twice. The reproducibility of the perfusion volume fraction and parenchymal diffusivity was calculated with the coefficient of variation, intraclass correlation coefficient, and the repeatability coefficient. ROIs included the normal-appearing white matter, cortex, deep gray matter, white matter hyperintensities, and vascular lesions.
RESULTS:Values for the perfusion volume fraction ranged from 2.42 to 3.97 x10–2 and for parenchymal diffusivity from 7.20 to 9.11 x 10–4 mm2/s, with higher values found in the white matter hyperintensities and vascular lesions. Coefficients of variation were <3.70% in normal-appearing tissue and <9.15% for lesions. Intraclass correlation coefficients were good to excellent, showing values ranging from 0.82 to 0.99 in all ROIs, except the deep gray matter and cortex, with intraclass correlation coefficients of 0.66 and 0.54, respectively. The repeatability coefficients ranged from 0.15 to 0.96 x 10–2 and 0.10 to 0.37 x 10–4 mm2/s for perfusion volume fraction and parenchymal diffusivity, respectively.
CONCLUSIONS:Good reproducibility of inversion recovery–intravoxel incoherent motion imaging was observed with low coefficients of variation and high intraclass correlation coefficients in normal-appearing tissue and lesion areas in cerebrovascular disease. Good reproducibility of inversion recovery–intravoxel incoherent motion imaging in cerebrovascular disease is feasible in monitoring disease progression or treatment responses in the clinic.
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Pheochromocytoma as a frequent false-positive in adrenal washout CT: A systematic review and meta-analysis
Abstract
Objective
To evaluate the proportion of pheochromocytomas meeting the criteria for adenoma on adrenal washout CT and the diagnostic performance of adrenal washout CT for differentiating adenoma from pheochromocytoma.
Methods
MEDLINE and EMBASE were searched to 28 March 2017. We included studies that used adrenal washout CT for characterisation of pheochromocytomas. Two independent reviewers assessed the methodological quality using Quality Assessment of Diagnostic Accuracy Studies-2. Proportions were pooled using an inverse variance method for calculating weights (random-effects). Sensitivity and specificity were pooled using hierarchical logistic regression modelling and plotted in a hierarchical summary receiver-operating-characteristics (HSROC) plot.
Results
Ten studies (114 pheochromocytomas) were included. The pooled proportion of pheochromocytomas meeting the criteria for adenomas was 35 % (95 % CI 20–51). For eight studies providing information on diagnostic performance, the pooled sensitivity and specificity for differentiating adenoma from pheochromocytoma were 0.97 (95 % CI 0.93–0.99) and 0.67 (95 % CI 0.44–0.84), respectively. The area under the HSROC curve was 0.97 (95 % CI 0.95–0.98).
Conclusions
There was a non-negligible proportion of pheochromocytomas meeting the criteria for adenoma on adrenal washout CT. Although overall diagnostic performance was excellent for differentiating adenoma from pheochromocytoma, specificity was relatively low.
Key Points
• Non-negligible proportion of pheochromocytomas can be mistaken for adenoma.
• Adrenal washout CT showed good sensitivity (97%) but relatively low specificity (67%).
• Findings other than washout percentage should be used when diagnosing pheochromocytomas
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The Left Atrio-Vertebral Ratio: a new simple means for assessing left atrial enlargement on Computed Tomography
Abstract
Objective
The purpose of this study is to describe a new method to quickly estimate left atrial enlargement (LAE) on Computed Tomography.
Methods
Left atrial (LA) volume was assessed with a 3D-threshold Hounsfield unit detection technique, including left atrial appendage and excluding pulmonary venous confluence, in 201 patients with ECG-gated 128-slice dual-source CT and indexed to body surface area. LA and vertebral axial diameter and area were measured at the bottom level of the right inferior pulmonary vein ostium. Ratio of LA diameter and surface on vertebra (LAVD and LAVA) were compared to LA volume. In accordance with the literature, a cutoff value of 78 ml/m2 was chosen for maximal normal LA volume.
Results
18% of LA was enlarged. The best cutoff values for LAE assessment were 2.5 for LAVD (AUC: 0.65; 95% CI: 0.58-0.73; sensitivity: 57%; specificity: 71%), and 3 for LAVA (AUC: 0.78; 95% CI: 0.72-0.84; sensitivity: 67%; specificity: 79%), with higher accuracy for LAVA (P=0.015). Inter-observer and intra-observer variability were either good or excellent for LAVD and LAVA (respective intraclass coefficients: 0.792 and 0.910; 0.912 and 0.937).
Conclusion
A left atrium area superior to three times the vertebral area indicates LAE with high specificity.
Key points
• Left atrial enlargement is a frequent condition associated with poor cardiac outcome.
• Left atrial enlargement is highly time-consuming to diagnose on CT.
• The left atrio-vertebral ratio quickly assesses left atrial enlargement.
• A left atrial area > three times vertebral area is highly specific.
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The effects of mild germinal matrix-intraventricular haemorrhage on the developmental white matter microstructure of preterm neonates: a DTI study
Abstract
Objectives
To evaluate white matter (WM) microstructural changes in preterm neonates (PN) with mild germinal matrix-intraventricular haemorrhage (mGMH-IVH) (grades I and II) and no other associated MRI abnormalities, and correlate them with gestational age (GA) and neurodevelopmental outcome.
Methods
Tract-based spatial-statistics (TBSS) was performed on DTI of 103 patients studied at term-equivalent age, to compare diffusional parameters (fractional anisotropy (FA), mean diffusivity (MD), radial diffusivity (RD), axial diffusivity (AD)) between mGMH-IVH neonates (24/103) and controls matched by GA at birth and sex. The relationship between DTI abnormalities, GA and neurodevelopmental outcome assessed with Griffiths' Developmental Scale-Revised:0-2 was explored using TBSS and Spearman-correlation analysis (p < .05).
Results
Affected neonates had lower FA, higher RD and MD of the corpus callosum, limbic pathways and cerebellar tracts. Extremely preterm neonates (GA < 29 weeks) presented more severe microstructural impairment (higher RD and MD) in periventricular regions. Neonates of GA ≥ 29 weeks had milder WM alterations (lower FA), also in subcortical WM. DTI abnormalities were associated with poorer locomotor, eye-hand coordination and performance outcomes at 24 months.
Conclusions
WM microstructural changes occur in PN with mGMH-IVH with a GA-dependent selective vulnerability of WM regions, and correlate with adverse neurodevelopmental outcome at 24 months.
Key Points
• DTI-TBSS analysis identifies WM microstructural changes in preterm neonates with mGMH-IVH.
• Extremely preterm neonates with mGMH-IVH presented more severe impairment of WM microstructure.
• Extremely preterm neonates with mGMH-IVH presented microstructural impairment of periventricular WM.
• mGMH-IVH affects subcortical WM in preterm neonates with gestational age ≥ 29 weeks.
• WM microstructural alterations are related to neurodevelopmental impairments at 24 months.
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Microflow imaging: New Doppler technology to detect low-grade inflammation in patients with arthritis
Abstract
Aim
To assess the efficacy of microvascular imaging in detecting low-grade inflammation in arthritis compared with Power Doppler ultrasound (PDUS).
Method and materials
Patients presenting for ultrasound with arthralgia were assessed with grey-scale, PDUS and Superb Microvascular Imaging (SMI). Videoclips were stored for analysis at a later date. Three musculoskeletal radiologists scored grey-scale changes, signal on PDUS and/or SMI within these joints. If a signal was detected on both PDUS and SMI, the readers graded the conspicuity of vascular signal from the two Doppler techniques using a visual analogue scale.
Results
Eighty-three patients were recruited with 134 small joints assessed. Eighty-nine of these demonstrated vascular flow with both PD and SMI, whilst in five no flow was detected. In 40 joints, vascularity was detected with SMI but not with PDUS (p = 0.007). Out of the 89 joints with vascularity on both SMI and PDUS, 23 were rated as being equal; while SMI scored moderately or markedly better in 45 cases (p <0.001).
Conclusion
SMI is a new Doppler technique that increases conspicuity of Doppler vascularity in symptomatic joints when compared to PDUS. This allows detection of low grade inflammation not visualised with Power Doppler in patients with arthritis.
Key Points
• SMI detects vascularity with improved resolution and sensitivity compared to Power Doppler.
• SMI can detect low-grade inflammation not seen with Power Doppler.
• Earlier detection of active inflammation could have significant impact on treatment paradigms.
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Carpal tunnel syndrome assessment with diffusion tensor imaging: Value of fractional anisotropy and apparent diffusion coefficient
Abstract
Objectives
To quantitatively assess carpal tunnel syndrome (CTS) with DTI by evaluating two approaches to determine cut-off values.
Methods
In forty patients with CTS diagnosis confirmed by nerve conduction studies (NCs) and 14 healthy subjects (mean age 58.54 and 57.8 years), cross-sectional area (CSA), apparent diffusion coefficient (ADC) and fractional anisotropy (FA) at single and multiple levels with intraobserver agreement were evaluated.
Results
Maximum and mean CSA and FA showed significant differences between healthy subjects and patients (12.85 mm2 vs. 28.18 mm2, p < 0.001, and 0.613 vs. 0.524, p=0.007, respectively) (10.12 mm2 vs. 19.9 mm2, p<0.001 and 0.617 vs. 0.54, p=0.003, respectively), but not maximum and mean ADC (p > 0.05). For cut-off values, mean and maximum CSA showed the same sensitivity and specificity (93.3 %). However, mean FA showed better sensitivity than maximum FA (82.6 % vs. 73.9 %), but lower specificity (66.7 % vs. 80 %), and significant correlation for maximum CSA, 97 % (p < 0.01), with good correlation for maximum ADC and FA, 84.5 % (p < 0.01) and 62 % (p=0.056), respectively.
Conclusions
CSA and FA showed significant differences between healthy subjects and patients. Single measurement at maximum CSA is suitable for FA determination.
Key Points
• DTI showed that FA is stronger than ADC for CTS diagnosis.
• Single- and multiple-level approaches were compared to determine FA and ADC.
• Single-level evaluation at the thickest MN cross-sectional area is sufficient.
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Thermal ablation of thyroid nodules: are radiofrequency ablation, microwave ablation and high intensity focused ultrasound equally safe and effective methods?
Abstract
Objectives
This study compares volume reduction of benign thyroid nodules three months after Radiofrequency Ablation (RFA), Microwave Ablation (MWA) or High Intensity Focused Ultrasound (HIFU) to evaluate which of these methods is the most effective and safe alternative to thyroidectomy or radioiodine therapy.
Material and Methods
Ninety-four patients (39 male, 55 female) with a total of 118 benign, symptomatic thyroid nodules were divided into three subgroups. HIFU was applied to 14 patients with small nodules. The other 80 patients were divided up into two groups of 40 patients each for RFA and MWA in the assumption that both methods are comparable effective. The pre-ablative and post-ablative volume was measured by ultrasound.
Results
RFA showed a significant volume reduction of nodules of 50 % (p<0.05), MWA of 44 % (p<0.05) and HIFU of 48 % (p<0.05) three months after ablation. None of the examined ablation techniques caused serious or permanent complications.
Conclusion
RFA, MWA and HIFU showed comparable results considering volume reduction. All methods are safe and effective treatments of benign thyroid nodules.
Key Points
• Thermal Ablation can be used to treat benign thyroid nodules
• Thermal Ablation can be an alternative to thyroidectomy or radioiodine therapy
• Radiofrequency Ablation, Microwave Ablation, High Intensity Focused Ultrasound are safe and effective
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Safety analysis of holmium-166 microsphere scout dose imaging during radioembolisation work-up: A cohort study
Abstract
Objective
Radioembolisation is generally preceded by a scout dose of technetium-99m-macroaggregated albumin to estimate extrahepatic shunting of activity. Holmium-166 microspheres can be used as a scout dose (±250 MBq) and as a therapeutic dose. The general toxicity of a holmium-166 scout dose (166Ho-SD) and safety concerns of an accidental extrahepatic deposition of 166Ho-SD were investigated.
Methods
All patients who received a 166Ho-SD in our institute were reviewed for general toxicity and extrahepatic depositions. The absorbed dose in extrahepatic tissue was calculated on SPECT/CT and correlated to clinical toxicities.
Results
In total, 82 patients were included. No relevant clinical toxicity occurred. Six patients had an extrahepatic deposition of 166Ho-SD (median administered activity 270 MBq). The extrahepatic depositions (median activity 3.7 MBq) were located in the duodenum (3x), gastric fundus, falciform ligament and the lesser curvature of the stomach, and were deposited in a median volume of 15.3 ml, which resulted in an estimated median absorbed dose of 3.6 Gy (range 0.3–13.8 Gy). No adverse events related to the extrahepatic deposition of the 166Ho-SD occurred after a median follow-up of 4 months (range 1–12 months).
Conclusion
These results support the safety of 250 MBq 166Ho-SD in a clinical setting.
Key Points
• A holmium-166 scout dose is safe in a clinical setting.
• Holmium-166 scout dose is a safe alternative for 99m Tc-MAA for radioembolisation work-up.
• Holmium-166 scout dose potentially has several benefits over 99m Tc-MAA for radioembolisation work-up.
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Rapid volumetric photoacoustic tomographic imaging with a Fabry-Perot ultrasound sensor depicts peripheral arteries and microvascular vasomotor responses to thermal stimuli
Abstract
Purpose
To determine if a new photoacoustic imaging (PAI) system successfully depicts (1) peripheral arteries and (2) microvascular circulatory changes in response to thermal stimuli.
Methods
Following ethical permission, 8 consenting subjects underwent PAI of the dorsalis pedis (DP) artery, and 13 completed PAI of the index fingertip. Finger images were obtained after immersion in warm (30-35 °C) or cold (10-15 °C) water to promote vasodilation or vasoconstriction. The PAI instrument used a Fabry-Perot interferometeric ultrasound sensor and a 30-Hz 750-nm pulsed excitation laser. Volumetric images were acquired through a 14 × 14 × 14-mm volume over 90 s. Images were evaluated subjectively and quantitatively to determine if PAI could depict cold-induced vasoconstriction. The full width at half maximum (FWHM) of resolvable vessels was measured.
Results
Fingertip vessels were visible in all participants, with mean FWHM of 125 μm. Two radiologists used PAI to correctly identify vasoconstricted fingertip capillary beds with 100% accuracy (95% CI 77.2-100.0%, p < 0.001). The number of voxels exhibiting vascular signal was significantly smaller after cold water immersion (cold: 5263 voxels; warm: 363,470 voxels, p < 0.001). The DP artery was visible in 7/8 participants (87.5%).
Conclusion
PAI achieves rapid, volumetric, high-resolution imaging of peripheral limb vessels and the microvasculature and is responsive to vasomotor changes induced by thermal stimuli.
Key points
• Fabry-Perot interferometer-based photoacoustic imaging (PAI) generates volumetric, high-resolution images of the peripheral vasculature.
• The system reliably detects thermally induced peripheral vasoconstriction (100% correct identification rate, p < 0.001).
• Vessels measuring less than 100 μm in diameter can be depicted in vivo.
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Differences in myocardial strain between pectus excavatum patients and healthy subjects assessed by cardiac MRI: a pilot study
Abstract
Objectives
To evaluate differences in myocardial strain between pectus excavatum (PE) patients and healthy subjects (HS) assessed by cardiac MRI using the feature-tracking algorithm.
Methods
Cardiac MRI was performed in 14 PE patients and 14 HS (9:5 male to female in each group; age 11–30 years) using a 3T scanner. Post-examination analysis included manual biventricular contouring with volumetry and ejection fraction measurement by two independent radiologists. Dedicated software was used for automated strain assessment.
Results
In five of the PE patients, the right ventricular ejection fraction was slightly impaired (40–44 %). PE patients had a significantly higher left ventricular longitudinal strain (P=0.004), mid (P=0.035) and apical (P=0.001) circumferential strain as well as apical circumferential strain rate (P=0.001), mid right ventricular circumferential strain (P=0.008) and strain rate (P=0.035), and apical right ventricular circumferential strain (P=0.012) and strain rate (P=0.044) than HS. The right ventricular longitudinal strain and strain rate did not differ significantly between PE patients and HS.
Conclusions
Myocardial strain differs significantly between PE patients and HS. Higher myocardial strain in the mid and apical ventricles of PE patients indicates a compensation mechanism to enhance ventricular output against basal sternal compression.
Key Points
• The right ventricle is frequently affected by the pectus excavatum deformity.
• Cardiac MRI revealed differences in myocardial strain in pectus excavatum patients.
• Pectus excavatum patients exhibited higher strain in the mid/apical ventricles.
• A compensation mechanism to enhance ventricular output against sternal compression is possible.
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Diffusion-weighted imaging in relation to morphology on dynamic contrast enhancement MRI: the diagnostic value of characterizing non-puerperal mastitis
Abstract
Objectives
To demonstrate the value of diffusion-weighted imaging (DWI) in the characterisation of mastitis lesions.
Methods
Sixty-one non-puerperal patients with pathologically confirmed single benign mastitis lesions underwent preoperative examinations with conventional MRI and axial DWI. Patients were categorised into three groups: (1) periductal mastitis (PDM), (2) granulomatous lobular mastitis (GLM), and (3) infectious abscess (IAB). Apparent diffusion coefficient (ADC) values of each lesion were recorded. A one-way ANOVA with logistic analysis was performed to compare ADC values and other parameters. Discriminative abilities of DWI modalities were compared using the area under the receiver operating characteristic curve (AUC). P < 0.05 was considered statistically significant.
Results
ADC values differed significantly among the three groups (P = 0.003) as well as between PDM and IAB and between PDM and GLM. The distribution of non-mass enhancement on dynamic contrast-enhanced (DCE) MRI differed significantly among the three groups (P = 0.03) but not between any two groups specifically. There were no differences in lesion location, patient age, T2WI or DWI signal intensity, enhancement type, non-mass internal enhancement, or mass enhancement characteristics among the three groups.
Conclusions
ADC values and the distribution of non-mass enhancement are valuable in classifying mastitis subtypes.
Key points
• Mastitis subtypes exhibit different characteristics on DWI and DCE MRI.
• ADC values are helpful in isolating PDM from other mastitis lesions.
• Distribution of non-mass enhancement also has value in comparing mastitis subtypes.
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Late iodine enhancement computed tomography with image subtraction for assessment of myocardial infarction
Abstract
Objective
To evaluate the feasibility of image subtraction in late iodine enhancement CT (LIE-CT) for assessment of myocardial infarction (MI).
Methods
A comprehensive cardiac CT protocol and late gadolinium enhancement MRI (LGE-MRI) was used to assess coronary artery disease in 27 patients. LIE-CT was performed after stress CT perfusion (CTP) and CT angiography. Subtraction LIE-CT was created by subtracting the mask volume of the left ventricle (LV) cavity from the original LIE-CT using CTP dataset. The %MI volume was quantified as the ratio of LIE to entire LV volume, and transmural extent (TME) of LIE was classified as 0%, 1–24%, 25–49%, 50–74% or 75–100%. These results were compared with LGE-MRI using the Spearman rank test, Bland-Altman method and chi-square test.
Results
One hundred twenty-five (29%) of 432 segments were positive on LGE-MRI. Correlation coefficients for original and subtraction LIE-CT to LGE-MRI were 0.79 and 0.85 for %MI volume. Concordances of the 5-point grading scale between original and subtraction LIE-CT with LGE-MRI were 75% and 84% for TME; concordance was significantly improved using the subtraction technique (p <0.05).
Conclusion
Subtraction LIE-CT allowed more accurate assessment of MI extent than the original LIE-CT.
Key Points
• Subtraction LIE-CT allows for accurate assessment of the extent of myocardial infarction.
• Subtraction LIE-CT shows a close correlation with LGE-MRI in %MI volume.
• Subtraction LIE-CT has significantly higher concordance with TME assessment than original LIE-CT.
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CT myocardial perfusion imaging: ready for prime time?
Abstract
The detection of functional coronary artery stenosis with coronary CT angiography (CCTA) is suboptimal. Additional CT myocardial perfusion imaging (CT-MPI) may be helpful to identify patients with myocardial ischaemia in whom coronary revascularization therapy would be beneficial. CT-MPI adds incremental diagnostic and prognostic value over obstructive disease on CCTA. It allows for the quantitation of myocardial blood flow and calculation of coronary flow reserve and shows good correlation with 15O-H2O positron emission tomography and invasive fractional flow reserve. In addition, patients prefer CCTA/CT-MPI over SPECT, MRI and invasive coronary angiography. CT-MPI is ready for clinical use for detecting myocardial ischaemia caused by obstructive disease. Nevertheless, the clinical utility of CT-MPI to identify ischaemia in patients with non-obstructive/microvascular disease still has to be established.
Key Points
• CT-MPI can improve the positive predictive value of CCTA for lesion-specific ischaemia.
• CT-MPI adds incremental prognostic value over CCTA for major adverse cardiac events.
• CT-MPI correlates with 15 O-H 2 O PET.
• CT-MPI/CCTA shows high overall patient satisfaction.
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Prediction of survival by texture-based automated quantitative assessment of regional disease patterns on CT in idiopathic pulmonary fibrosis
Abstract
Objectives
To retrospectively investigate whether the baseline extent and 1-year change in regional disease patterns on CT can predict survival of patients with idiopathic pulmonary fibrosis (IPF).
Methods
A total of 144 IPF patients with CT scans at the time of diagnosis and 1 year later were included. The extents of five regional disease patterns were quantified using an in-house texture-based automated system. The fibrosis score was defined as the sum of the extent of honeycombing and reticular opacity. The Cox proportional hazard model was used to determine the independent predictors of survival.
Results
A total of 106 patients (73.6%) died during the follow-up period. Univariate analysis revealed that age, baseline forced vital capacity, total lung capacity, diffusing capacity of the lung for carbon monoxide, six-minute walk distance, desaturation, honeycombing, reticular opacity, fibrosis score, and interval changes in honeycombing and fibrosis score were significantly associated with survival. Multivariate analysis revealed that age, desaturation, fibrosis score and interval change in fibrosis score were significant independent predictors of survival (p = 0.003, <0.001, 0.001 and <0.001). The C-index for the developed model was 0.768.
Conclusion
Texture-based, automated CT quantification of fibrosis can be used as an independent predictor of survival in IPF patients.
Key Points
• Automated quantified fibrosis on CT was a significant predictor of survival.
• Automated quantified interval change in fibrosis on CT was an independent predictor.
• The predictive model showed comparable discriminative power with a C-index of 0.768.
• Automated CT quantification can be considered to evaluate prognosis in routine practice.
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Editorial Board
Publication date: April 2018
Source:Journal of Environmental Radioactivity, Volumes 184–185
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Anthropogenic 137Cs on atmospheric aerosols in Bratislava and around nuclear power plants in Slovakia
Publication date: April 2018
Source:Journal of Environmental Radioactivity, Volumes 184–185
Author(s): M. Ješkovský, M. Lištjak, I. Sýkora, O. Slávik, P.P. Povinec
Nuclear power plants (NPPs) have been one of the sources of anthropogenic radionuclides in the environment. This work combines the results from monitoring stations around NPPs in Slovakia (Mochovce and Jaslovské Bohunice) and academic measurements at the Comenius University campus in Bratislava. Most of the atmospheric 137Cs in this region come from the resuspension of the Chernobyl-derived 137Cs, as well as caesium produced during nuclear weapons testing. By comparison of the obtained results at NPPs with Bratislava data, radiation impacts of the NPPs on the local environments have been estimated to be negligible.
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Tritium and radiocarbon in the western North Pacific waters: post-Fukushima situation
Publication date: April 2018
Source:Journal of Environmental Radioactivity, Volumes 184–185
Author(s): Jakub Kaizer, Michio Aoyama, Yuichiro Kumamoto, Mihály Molnár, László Palcsu, Pavel P. Povinec
Impact of the Fukushima Dai-ichi Nuclear Power Plant (FNPP1) accident on tritium (3H) and radiocarbon (14C) levels in the water column of the western North Pacific Ocean in winter 2012 is evaluated and compared with radiocesium (134,137Cs) data collected for the same region. Tritium concentrations in surface seawater, varying between 0.4 and 2.0 TU (47.2–236 Bq m−3), follow the Fukushima radiocesium trend, however, some differences in the vertical profiles were observed, namely in depths of 50–400 m. No correlation was visible in the case of 14C, whose surface Δ14C levels raised from negative values (about −40‰) in the northern part of transect, to positive values (∼68‰) near the equator. Homogenously mixed 14C levels in the subsurface layers were observed at all stations. Sixteen surface (from 30 in total) and 6 water profile (from 7) stations were affected by the Fukushima tritium. Surface and vertical profile data together with the calculated water column inventories indicate that the total amount of the FNPP1-derived tritium deposited to the western North Pacific Ocean was 0.7 ± 0.3 PBq. No clear impact of the Fukushima accident on 14C levels in the western North Pacific was observed.
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An aerosol particle containing enriched uranium encountered in the remote upper troposphere
Publication date: April 2018
Source:Journal of Environmental Radioactivity, Volumes 184–185
Author(s): D.M. Murphy, K.D. Froyd, E. Apel, D. Blake, N. Blake, N. Evangeliou, R.S. Hornbrook, J. Peischl, E. Ray, T.B. Ryerson, C. Thompson, A. Stohl
We describe a submicron aerosol particle sampled at an altitude of 7 km near the Aleutian Islands that contained a small percentage of enriched uranium oxide. 235U was 3.1 ± 0.5% of 238U. During twenty years of aircraft sampling of millions of particles in the global atmosphere, we have rarely encountered a particle with a similarly high content of 238U and never a particle with enriched 235U. The bulk of the particle consisted of material consistent with combustion of heavy fuel oil. Analysis of wind trajectories and particle dispersion model results show that the particle could have originated from a variety of areas across Asia. The source of such a particle is unclear, and the particle is described here in case it indicates a novel source where enriched uranium was dispersed.
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Validation of an advanced analytical procedure applied to the measurement of environmental radioactivity
Publication date: April 2018
Source:Journal of Environmental Radioactivity, Volumes 184–185
Author(s): Tran Thien Thanh, Le Quang Vuong, Phan Long Ho, Huynh Dinh Chuong, Vo Hoang Nguyen, Chau Van Tao
In this work, an advanced analytical procedure was applied to calculate radioactivity in spiked water samples in a close geometry gamma spectroscopy. It included MCNP-CP code in order to calculate the coincidence summing correction factor (CSF). The CSF results were validated by a deterministic method using ETNA code for both p-type HPGe detectors. It showed that a good agreement for both codes. Finally, the validity of the developed procedure was confirmed by a proficiency test to calculate the activities of various radionuclides. The results of the radioactivity measurement with both detectors using the advanced analytical procedure were received the ''Accepted'' statuses following the proficiency test.
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Xenon adsorption on geological media and implications for radionuclide signatures
Publication date: Available online 13 February 2018
Source:Journal of Environmental Radioactivity
Author(s): M.J. Paul, S.R. Biegalski, D.A. Haas, H. Jiang, H. Daigle, J.D. Lowrey
The detection of radioactive noble gases is a primary technology for verifying compliance with the pending Comprehensive Nuclear-Test-Ban Treaty. A fundamental challenge in applying this technology for detecting underground nuclear explosions is estimating the timing and magnitude of the radionuclide signatures. While the primary mechanism for transport is advective transport, either through barometric pumping or thermally driven advection, diffusive transport in the surrounding matrix also plays a secondary role. From the study of primordial noble gas signatures, it is known that xenon has a strong physical adsorption affinity in shale formations. Given the unselective nature of physical adsorption, isotherm measurements reported here show that non-trivial amounts of xenon adsorb on a variety of media, in addition to shale. A dual-porosity model is then discussed demonstrating that sorption amplifies the diffusive uptake of an adsorbing matrix from a fracture. This effect may reduce the radioxenon signature down to approximately one-tenth, similar to primordial xenon isotopic signatures.
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Vertical distribution of 137Cs in grassland soils disturbed by moles (Talpa europaea L.)
Publication date: April 2018
Source:Journal of Environmental Radioactivity, Volumes 184–185
Author(s): V. Ramzaev, A. Barkovsky
Activity of biota is one of the factors influencing vertical migration of radionuclides deposited from the atmosphere onto the ground surface. The goal of this work was to study the vertical distribution of 137Cs in grassland soils disturbed by moles (Talpa europaea L.) in comparison with undisturbed grassland soils. Field observations and soil sampling were carried out in the areas of eight settlements in the Klintsovskiy, Krasnogorskiy and Novozybkovskiy districts of the Bryansk region, Russia in six years during the period 1999–2016. The study sites had been heavily contaminated by Chernobyl fallout in 1986. Activity of 137Cs in soil samples was determined by γ-ray spectrometry. 137Cs surface ground contamination levels at the studied plots (n = 17) ranged from 327 kBq m−2 to 2360 kBq m−2 with a mean of 1000 kBq m−2 and a median of 700 kBq m−2. The position of the 137Cs migration centre in the soil in 2010–2016 was significantly (the Mann-Whitney U test, P < .01) deeper at mole-disturbed plots (median = 5.99 cm or 6.64 g cm−2, n = 6) compared to the undisturbed ones (median = 2.48 cm or 2.35 g cm−2, n = 6). The 137Cs migration rate at mole-disturbed plots (median = 0.26 g cm−2 y−1, mean = 0.31 g cm−2 y−1) was significantly higher (by a factor of 3) than at undisturbed plots (median = 0.08 g cm−2 y−1, mean = 0.10 g cm−2 y−1). The difference in the migration rates between the mole-disturbed and undisturbed plots (median = 0.18 g cm−2 y−1, mean = 0.21 g cm−2 y−1) reasonably corresponded to the mass of soil that might be ejected by moles per unit area per year. The results of this study indicate that the burrowing activity of moles has increased vertical migration of Chernobyl-derived radiocaesium in the grassland soils.
Graphical abstract
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Correction to: Baseline and annual repeat rounds of screening: implications for optimal regimens of screening
Abstract
The original version of this article unfortunately contained a mistake. The conflict of interest was incorrect.
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When the Reading Room Meets the Team Room: Resident Perspectives from Radiology and Internal Medicine on the Impact of Personal Communication after Implementing a Resident-led Radiology Rounds
Publication date: Available online 13 February 2018
Source:Current Problems in Diagnostic Radiology
Author(s): Andrew J. Klobuka, John Lee, Raquel Buranosky, Matthew Heller
Current radiology and internal medicine residents have trained entirely in the post-PACS implementation era and thus have largely missed out on the benefits of in-person, two-way communication between radiologists and consulting clinicians. The purpose of this study is to broadly explore resident perspectives from these groups on the desire for personal contact between radiologists and referring physicians and the impact of improved contact on clinical practice. A Radiology Rounds was implemented in which radiology residents travel to the internal medicine teaching service teams to discuss their inpatients and review ordered imaging biweekly. Surveys were given to both cohorts following 9 months of implementation. 23/49 Diagnostic Radiology (DR) and 72/197 Internal Medicine (IM) residents responded. 83% of DR and 96% of IM residents desired more personal contact between radiologists and clinicians. 92% of DR residents agree that contact with referring clinicians changes their approach to a study. 96% of IM residents agree that personal contact with a radiologist has changed patient management in a way that they otherwise would not have done having simply read a report. 85% of DR residents report that more clinician contact will improve resource utilization and 96% report that it will improve care quality. 99% of IM residents report that increased access to a radiologist would make selecting the most appropriate imaging study easier in various clinical scenarios. A majority of IM residents prefer radiology reports that provide specific next-step recommendations and that include arrows/key-image series. We conclude that the newest generation of physicians is already attuned to the value of a radiologist who plays an active, in-person role in the clinical decision-making process.
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A Dynamic Graph Cuts Method with Integrated Multiple Feature Maps for Segmenting Kidneys in 2D Ultrasound Images
Publication date: Available online 12 February 2018
Source:Academic Radiology
Author(s): Qiang Zheng, Steven Warner, Gregory Tasian, Yong Fan
Rationale and ObjectivesAutomatic segmentation of kidneys in ultrasound (US) images remains a challenging task because of high speckle noise, low contrast, and large appearance variations of kidneys in US images. Because texture features may improve the US image segmentation performance, we propose a novel graph cuts method to segment kidney in US images by integrating image intensity information and texture feature maps.Materials and MethodsWe develop a new graph cuts-based method to segment kidney US images by integrating original image intensity information and texture feature maps extracted using Gabor filters. To handle large appearance variation within kidney images and improve computational efficiency, we build a graph of image pixels close to kidney boundary instead of building a graph of the whole image. To make the kidney segmentation robust to weak boundaries, we adopt localized regional information to measure similarity between image pixels for computing edge weights to build the graph of image pixels. The localized graph is dynamically updated and the graph cuts-based segmentation iteratively progresses until convergence. Our method has been evaluated based on kidney US images of 85 subjects. The imaging data of 20 randomly selected subjects were used as training data to tune parameters of the image segmentation method, and the remaining data were used as testing data for validation.ResultsExperiment results demonstrated that the proposed method obtained promising segmentation results for bilateral kidneys (average Dice index = 0.9446, average mean distance = 2.2551, average specificity = 0.9971, average accuracy = 0.9919), better than other methods under comparison (P < .05, paired Wilcoxon rank sum tests).ConclusionsThe proposed method achieved promising performance for segmenting kidneys in two-dimensional US images, better than segmentation methods built on any single channel of image information. This method will facilitate extraction of kidney characteristics that may predict important clinical outcomes such as progression of chronic kidney disease.
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Neurometabolites Alteration in the Acute Phase of Mild Traumatic Brain Injury (mTBI)
Publication date: Available online 12 February 2018
Source:Academic Radiology
Author(s): Vigneswaran Veeramuthu, Pohchoo Seow, Vairavan Narayanan, Jeannie Hisu Ding Wong, Li Kuo Tan, Aditya Tri Hernowo, Norlisah Ramli
Rationale and ObjectivesMagnetic resonance spectroscopy is a noninvasive imaging technique that allows for reliable assessment of microscopic changes in brain cytoarchitecture, neuronal injuries, and neurochemical changes resultant from traumatic insults. We aimed to evaluate the acute alteration of neurometabolites in complicated and uncomplicated mild traumatic brain injury (mTBI) patients in comparison to control subjects using proton magnetic resonance spectroscopy (1H magnetic resonance spectroscopy).Material and MethodsForty-eight subjects (23 complicated mTBI [cmTBI] patients, 12 uncomplicated mTBI [umTBI] patients, and 13 controls) underwent magnetic resonance imaging scan with additional single voxel spectroscopy sequence. Magnetic resonance imaging scans for patients were done at an average of 10 hours (standard deviation 4.26) post injury. The single voxel spectroscopy adjacent to side of injury and noninjury regions were analysed to obtain absolute concentrations and ratio relative to creatine of the neurometabolites. One-way analysis of variance was performed to compare neurometabolite concentrations of the three groups, and a correlation study was done between the neurometabolite concentration and Glasgow Coma Scale.ResultsSignificant difference was found in ratio of N-acetylaspartate to creatine (NAA/Cr + PCr) (χ2(2) = 0.22, P < .05) between the groups. The sum of NAA and N-acetylaspartylglutamate (NAAG) also shows significant differences in both the absolute concentration (NAA + NAAG) and ratio to creatine (NAA + NAAG/Cr + PCr) between groups (χ2(2) = 4.03, P < .05and (χ2(2) = 0.79, P < .05)). NAA values were lower in cmTBI and umTBI compared to control group. A moderate weak positive correlation were found between Glasgow Coma Scale with NAA/Cr + PCr (ρ = 0.36, P < .05 and NAA + NAAG/Cr + PCr (ρ = 0.45, P < .05)), whereas a moderate correlation was seen with NAA + NAAG (ρ = 0.38, P < .05).ConclusionNeurometabolite alterations were already apparent at onset of both complicated and uncomplicated traumatic brain injury. The ratio of NAA and NAAG has potential to serve as a biomarker reflecting injury severity in a quantifiable manner as it discriminates between the complicated and uncomplicated cases of mTBI.
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Gender Trends in Academic Radiology Publication in the United States Revisited
Publication date: Available online 12 February 2018
Source:Academic Radiology
Author(s): Erin E. O'Connor, Pauline Chen, Brian Weston, Redmond Anderson, Timothy Zeffiro, Awad Ahmed, Thomas A. Zeffiro
Rationale and ObjectivesAlthough substantial increases in publications by female academic radiologists have appeared over the last several decades, it is possible that the rate of increase is decreasing. We examined temporal trends in gender composition for full-time radiology faculty, radiology residents, and medical students over a 46-year period.MethodsWe examined authorship gender trends to determine if the increases in female authorship seen since 1970 have been sustained in recent years and whether female radiologists continue to publish in proportion to their numbers in academic departments. Original articles for selected years in Radiology and in the American Journal of Roentgenology between 1970 and 2016 were examined to determine the gender of first, corresponding, and last authors. Generalized linear models evaluated (1) changes in proportions of female authorship over time and (2) associations between proportions of female authorship and female radiology faculty representation.ResultsWhile linear increases in first, corresponding, and senior authorships were observed for female radiologists from 1970 to 2000, the rate of increase in female first and corresponding authorships then changed, with the slope of the first author relationship decreasing from 0.81 to 0.34, corresponding to 47% fewer female first authors added per year. In contrast, the proportion of female last authorship continued to increase at the same rate. The proportion of female first authorship was linearly related to the proportion of female radiology faculty from 1970 to 2016.ConclusionsAnnual increases in first author academic productivity of female radiologists have lessened in the past 16 years, possibly related to reductions in the growth of female radiology faculty and trainees. As mixed, compared to homogeneous gender, authorship teams are associated with more citations, efforts to encourage more women to pursue careers in academic radiology could benefit the radiology research community.
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Invited Commentary
Publication date: Available online 12 February 2018
Source:Academic Radiology
Author(s): Charles E. Ray
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Nigrostriatal dopamine transporter availability in early Parkinson's disease
ABSTRACT
Background: The imaging of biomarkers for characterization of dopaminergic impairment in Parkinson's disease (PD) is useful for diagnosis, patient stratification, and assessment of treatment outcomes. [18F]FE-PE2I is an improved imaging tool allowing for detailed mapping of the dopamine transporter protein in the nigro-striatal system at the level of cell bodies (substantia nigra), axons, and presynaptic terminals (striatum).
Objectives: The objective of this study was to compare the dopamine transporter protein loss in the presynaptic terminals to that in the cell bodies and axons in early PD patients using [18F](E)-N-(3-iodoprop-2-enyl)-2b-carbofluoroethoxy-3b-(4′-methyl-phenyl) nortropane ([18F]FE-PE2I) and high-resolution PET.
Methods: A total of 20 early PD patients (15 men/5 women, 62 ± 8 years) and 20 controls (15 men/5 women, 62 ± 7 years) underwent high-resolution [18F]FE-PE2I PET. Dopamine transporter protein availability was estimated for the different nigro-striatal regions and expressed as nondisplaceable binding potential values.
Results: When compared with controls, the binding potential values in PD patients were reduced by 36% to 70% in presynaptic terminals and by 30% in cell bodies. Dopamine transporter availability along the tracts was not different between the 2 groups (controls 0.5 ± 0.1 vs PD 0.4 ± 0.1).
Conclusions: This is the first study that examines dopamine transporter protein availability in vivo within the entire nigro-striatal pathway. The results suggest that at early stages of symptomatic PD a greater loss is observed at the level of the axonal terminals when compared with cell bodies and axons of dopaminergic neurons. The findings suggest a relative preservation of cell bodies in early PD, which might be relevant for novel disease-modifying strategies. © 2018 International Parkinson and Movement Disorder Society
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Autonomic dysfunction in Parkinson's disease and other synucleinopathies: Introduction to the series
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Why palliative care applies to Parkinson's disease
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Ataxia-telangiectasia: A review of movement disorders, clinical features, and genotype correlations
ABSTRACT
Ataxia-telangiectasia is an autosomal recessive neurodegenerative disorder that was initially thought to present exclusively in childhood. With the discovery of the ATM gene, the phenotypic spectrum of the condition has expanded. This review elaborates the expanded phenomenology, including oculomotor apraxia and immunodeficiency, and estimates the presence of each movement disorder feature from previously reported literature. Initial manifestations of Ataxia-telangiectasia include cerebellar symptoms (67%), dystonia (18%), choreoathetosis (10%), and tremor (4%), with parkinsonism and myoclonus not reported as initial features. The prevalence of movement disorders during the course of the disease includes cerebellar symptoms (96%), dystonia (89%), parkinsonism (41%), choreoathetosis (89%), myoclonus (92%), and tremor (74%). Phenomenology and age of onset is modulated by presence of residual ATM kinase activity, with genotypes heavily truncating the ATM protein associated with the most severe phenotypes. Ataxia-telangiectasia commonly results in a spectrum of movement disorders beyond ataxia and telangiectasias. © 2018 International Parkinson and Movement Disorder Society
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A controversy on the role of short-chain fatty acids in the pathogenesis of Parkinson's disease
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Performance of the Movement Disorders Society criteria for prodromal Parkinson's disease: A population-based 10-year study
ABSTRACT
Objective: We aimed to identify prodromal Parkinson's disease (PD) and its predictive accuracy for incident PD in an unselected elderly population and to estimate the relevance of this approach for future neuroprotection trials.
Methods: We applied the recently published Movement Disorders Society (MDS) research criteria for prodromal PD to participants of the prospective population-based Bruneck Study of the 2005 assessment (n = 574, ages 55-94 years). Cases of incident PD were identified at 3-year, 5-year, and 10-year follow-up visits. We calculated predictive accuracies of baseline prodromal PD status for incident cases, and, based on them, estimated sample sizes for neuroprotection trials with conversion to PD as the primary outcome.
Results: Baseline status of probable prodromal PD (n = 12) had a specificity in predicting incident PD of 98.8% (95% confidence interval, 97.3%-99.5%), a sensitivity of 66.7% (29.6%-90.8%), and a positive predictive value of 40.0% (16.7%-68.8%) over 3 years. Specificity remained stable with increasing follow-up time, sensitivity decreased to 54.6% (28.0%-78.8%) over 5 years and to 35.0% (18.0%-56.8%) over 10 years, whereas positive predictive value rose to 60.0% (31.2%-83.3%) and 77.8% (44.3%-94.7%), respectively. Sample size estimates at 80% power in an intention-to-treat approach ranged from 108 to 540 patients with probable prodromal PD depending on trial duration (3-5 years) and effect size of the agent (30%-50%).
Conclusions: Our findings show that the MDS criteria for prodromal PD yield moderate to high predictive power for incident PD in a community-based setting and may thus be helpful to define target populations of future neuroprotection trials. © 2018 International Parkinson and Movement Disorder Society
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Multitarget transcranial direct current stimulation for freezing of gait in Parkinson's disease
ABSTRACT
Background: Recent findings suggest that transcranial direct current stimulation of the primary motor cortex may ameliorate freezing of gait. However, the effects of multitarget simultaneous stimulation of motor and cognitive networks are mostly unknown. The objective of this study was to evaluate the effects of multitarget transcranial direct current stimulation of the primary motor cortex and left dorsolateral prefrontal cortex on freezing of gait and related outcomes.
Methods: Twenty patients with Parkinson's disease and freezing of gait received 20 minutes of transcranial direct current stimulation on 3 separate visits. Transcranial direct current stimulation targeted the primary motor cortex and left dorsolateral prefrontal cortex simultaneously, primary motor cortex only, or sham stimulation (order randomized and double-blinded assessments). Participants completed a freezing of gait-provoking test, the Timed Up and Go, and the Stroop test before and after each transcranial direct current stimulation session.
Results: Performance on the freezing of gait-provoking test (P = 0.010), Timed Up and Go (P = 0.006), and the Stroop test (P = 0.016) improved after simultaneous stimulation of the primary motor cortex and left dorsolateral prefrontal cortex, but not after primary motor cortex only or sham stimulation.
Conclusions: Transcranial direct current stimulation designed to simultaneously target motor and cognitive regions apparently induces immediate aftereffects in the brain that translate into reduced freezing of gait and improvements in executive function and mobility. © 2018 International Parkinson and Movement Disorder Society
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Relationship between cerebrospinal fluid biomarkers and structural brain network properties in Parkinson's disease
ABSTRACT
Background: Pathological accumulation of α-synuclein, amyloid-β42, and tau proteins in the brain is considered critical for development of various neurodegenerative diseases.
Objectives: We investigated the association between CSF levels of these biomarkers, brain structural connectivity, and the UPDRS in PD.
Methods: Diffusion tensor images and CSF biomarkers (α-synuclein, amyloid-β42, total tau, and phosphorylated tau181) from 132 drug-naïve, nondemented PD patients and 61 healthy controls were obtained from the Parkinson's Progression Markers Initiative database. After network reconstruction of structural connectivity patterns, global interconnectivity measures (including global efficiency, clustering coefficient, and characteristic path length) and local efficiency were calculated. Network properties and CSF biomarkers were compared between PD patients and healthy controls. The association of CSF biomarkers with network properties and UPDRS-III score was investigated.
Results: Global measures (but not local efficiency) and CSF α-synuclein were significantly lower in PD patients. Global efficiency and clustering coefficient correlated positively with α-synuclein, Aβ42, and total tau CSF levels. Furthermore, these CSF biomarkers showed no significant association with the UPDRS-III score.
Conclusions: This study examined the association of CSF biomarkers that reflect the brain pathology, with structural brain connectivity and UPDRS-III in PD. Our results revealed an association between the abnormal aggregation of α-synuclein, Aβ42, and tau proteins and structural connectivity disruption in PD patients. In summary, a combination of structural imaging and measurement of CSF biomarkers provide a better understanding of the pathogenesis of PD. © 2018 International Parkinson and Movement Disorder Society
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Follow-up for patients with metal-on-metal hip replacements: are the new MHRA recommendations justified?
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Forty-nine gastric cancer cell lines with integrative genomic profiling for development of c-MET inhibitor
Abstract
Receptor tyrosine kinase MET (c-MET) has received considerable attention as a potential target for gastric cancer (GC) therapy and a number of c-MET inhibitors have been developed. For successful drug development, proper preclinical studies especially using patient derived cancer cell lines are very important. We profiled MET and MET-related characteristics in 49 GC cell lines to utilize them as models in preclinical studies of GC. Forty-nine cell lines were analyzed for genetic, biological, and molecular status to characterize MET and MET-related molecules. Four c-MET inhibitors were tested to elucidate the dependency on MET pathway in the 49 GC cell lines. Six of 49 cell lines were MET amplified with overexpression of c-MET and p-MET. The variants of MET were not associated with c-MET expression or amplification. Hs746T showed an exon 14 deletion in conjunction with MET amplification. The cell lines were divided into six MET amplified, two c-MET overexpressed, two hepatocyte growth factor (HGF) overexpressed, and thirty-nine MET negative subgroups. Except tivantinib, the c-MET inhibitors showed higher inhibition (%) in MET amplified than in MET non-amplified cell lines that MET amplified cell lines showed MET pathway dependency. However, the c-MET overexpressed and HGF overexpressed cell lines showed moderate dependency on MET pathway. Well characterized cell lines are very important in studying drug development. Our 49 GC cell lines had various characteristics of MET and MET-related molecules and MET pathway dependency. These provide a promising platform for development of various RTK inhibitors including c-MET inhibitors. This article is protected by copyright. All rights reserved.
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Post-diagnosis alcohol intake and prostate cancer survival: A population-based cohort study
Abstract
Alcohol consumption has been declared a Group 1 carcinogen by the International Agency for Research on Cancer (IARC) and is a potential risk factor for several types of cancer mortality. However, evidence for an association with prostate cancer survival remains inconsistent. We examined how alcohol consumption post-diagnosis was associated with survival after prostate cancer diagnosis.
Men diagnosed with prostate cancer (n=829) in Alberta, Canada between the years 1997-2000 were recruited into a population-based case-control study and then followed for up to 19 years for survival outcomes. Pre- and post-diagnosis alcohol consumption, clinical characteristics and lifestyle factors were collected through in-person interviews shortly after diagnosis and again 2-3 years post-diagnosis. Cox proportional hazards were used to examine how post-diagnosis alcohol consumption was associated with all-cause and prostate cancer-specific mortality (competing risk analysis too), in addition to first recurrence/progression or new primary cancer.
Most participants reported drinking alcohol (≥once a month for six months) post-diagnosis (n=589, 71.0%). Exceeding Canadian Cancer Society (CCS) alcohol consumption recommendations (≥2 drinks/day) post-diagnosis was associated with prostate cancer-specific mortality relative to non-drinkers (aHR: 1.82, 95% CI: 1.07-3.10) with borderline evidence of a linear trend. Interestingly, those in the highest quartile of drinks/week pre- and post-diagnosis also had a two-fold increase for prostate-specific mortality (aHR: 2.67, 95% CI: 1.28-5.56) while controlling for competing risks.
Our results support post-diagnosis alcohol consumption was associated with increased mortality after prostate cancer diagnosis, specifically for prostate cancer-related death. Future studies focused on confirming this burden of disease are warranted. This article is protected by copyright. All rights reserved.
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