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Τετάρτη, 14 Μαρτίου 2018

“X-Map 2.0” for Edema Signal Enhancement for Acute Ischemic Stroke Using Non–Contrast-Enhanced Dual-Energy Computed Tomography

Objectives A novel imaging technique ("X-map") has been developed to identify acute ischemic lesions for stroke patients using non–contrast-enhanced dual-energy computed tomography (NE-DE-CT). Using the 3-material decomposition technique, the original X-map ("X-map 1.0") eliminates fat and bone from the images, suppresses the gray matter (GM)-white matter (WM) tissue contrast, and makes signals of edema induced by severe ischemia easier to detect. The aim of this study was to address the following 2 problems with the X-map 1.0: (1) biases in CT numbers (or artifacts) near the skull of NE-DE-CT images and (2) large intrapatient and interpatient variations in X-map 1.0 values. Materials and Methods We improved both an iterative beam-hardening correction (iBHC) method and the X-map algorithm. The new iBHC (iBHC2) modeled x-ray physics more accurately. The new X-map ("X-map 2.0") estimated regional GM values—thus, maximizing the ability to suppress the GM-WM contrast, make edema signals quantitative, and enhance the edema signals that denote an increased water density for each pixel. We performed a retrospective study of 11 patients (3 men, 8 women; mean age, 76.3 years; range, 68-90 years) who presented to the emergency department with symptoms of acute stroke. Images were reconstructed with the old iBHC (iBHC1) and the iBHC2, and biases in CT numbers near the skull were measured. Both X-map 2.0 maps and X-map 1.0 maps were computed from iBHC2 images, both with and without a material decomposition-based edema signal enhancement (ESE) process. X-map values were measured at 5 to 9 locations on GM without infarct per patient; the mean value was calculated for each patient (we call it the patient-mean X-map value) and subtracted from the measured X-map values to generate zero-mean X-map values. The standard deviation of the patient-mean X-map values over multiple patients denotes the interpatient variation; the standard deviation over multiple zero-mean X-map values denotes the intrapatient variation. The Levene F test was performed to assess the difference in the standard deviations with different algorithms. Using 5 patient data who had diffusion weighted imaging (DWI) within 2 hours of NE-DE-CT, mean values at and near ischemic lesions were measured at 7 to 14 locations per patient with X-map images, CT images (low kV and high kV), and DWI images. The Pearson correlation coefficient was calculated between a normalized increase in DWI signals and either X-map or CT. Results The bias in CT numbers was lower with iBHC2 than with iBHC1 in both high- and low-kV images (2.5 ± 2.0 HU [95% confidence interval (CI), 1.3–3.8 HU] for iBHC2 vs 6.9 ± 2.3 HU [95% CI, 5.4–8.3 HU] for iBHC1 with high-kV images, P

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Detection of Subsolid Nodules in Lung Cancer Screening: Complementary Sensitivity of Visual Reading and Computer-Aided Diagnosis

Objectives The aim of this study was to compare computer-aided diagnosis (CAD) and visual reading for the detection of subsolid nodules (SSNs) in volumetrl measuremic low-dose computed tomography (LDCT) for lung cancer screening. Materials and Methods Prospective visual detection (VD) and manuaent of SSN were performed in the 2303 baseline volumetric LDCTs of the Multicenter Italian Lung Detection trial. Baseline and 2- and 4-year LDCTs underwent retrospective CAD analysis, subsequently reviewed by 2 experienced thoracic radiologists. The reference standard was defined by the cumulative number of SSNs detected by any reading method between VD and CAD. The number of false-positive CAD marks per scan (FPSSN/scan) was calculated. The positive predictive value of CAD was quantified per nodule (PPVSSN) and per screenee (PPVScreenee). The sensitivity and negative predictive value were compared between CAD and VD. The longitudinal 3-time-point sensitivity of CAD was calculated in the subgroup of persistent SSNs seen by VD (ratio between the prevalent SSNs detected by CAD through 3 time points and the total number of persistent prevalent SSNs detected by VD) to test the sensitivity of iterated CAD analysis during a screening program. Semiautomatic characteristics (diameter, volume, and mass; both for whole nodule and solid component) were compared between SSN detected CAD-only or VD-only to investigate whether either reading method could suffer from specific sensitivity weakness related to SSN features. Semiautomatic and manual diameters were compared using Spearman ρ correlation and Bland-Altman plot. Results Computer-aided diagnosis and VD detected a total of 194 SSNs in 6.7% (155/2,303) of screenees at baseline LDCT. The CAD showed mean FPSSN/scan of 0.26 (604/2,303); PPVSSN 22.5% (175/779) for any SSN, with 54.4% (37/68) for PSN and 19.4% for NSN (138/711; P

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Reduction of Artifacts Caused by Deep Brain Stimulating Electrodes in Cranial Computed Tomography Imaging by Means of Virtual Monoenergetic Images, Metal Artifact Reduction Algorithms, and Their Combination

Objectives The aim of this study was to evaluate the reduction of artifacts from deep brain stimulation electrodes (DBS) using an iterative metal artifact reduction algorithm (O-MAR), virtual monoenergetic images (VMI), and both in combination in postoperative spectral detector computed tomography using a dual-layer detector (spectral detector computed tomography [SDCT]) of the head. Material and Methods Nonanthropomorphic phantoms with different DBS leads were examined on SDCT; in 1 phantom periprocedural bleeding was simulated. A total of 20 patients who underwent SDCT after DBS implantation between October 2016 and April 2017 were included in this institutional review board–approved retrospective study. Images were reconstructed using standard-of-care iterative reconstruction (CI) and VMI, each with and without O-MAR processing (IR and MAR). Artifacts were quantified by determining the percentage integrity uniformity in an annular region of 1.4 cm2 around the DBS lead; a percentage integrity uniformity of 100% indicates the absence of artifacts. In phantoms, conspicuity of blood was determined on a binary scale, whereas in patients, image quality, DBS lead assessment, and extent of artifact reduction were assessed on Likert scales by 2 radiologists. Statistical significance was assessed using analysis of variance and Wilcoxon tests; sensitivity and specificity were calculated. Results The O-MAR processing significantly decreased artifacts in phantom and patients (P ≤ 0.05), whereas VMI did not reduce artifact burden compared with corresponding CI (P > 0.05): for example, CI-IR/MAR and 200 keV-IR/MAR for patients: 76.3%/90.7% and 75.9%/91.2%, respectively. Qualitatively, overall image quality was not improved (P > 0.05) and MAR improved DBS assessment (CI-IR/MAR: 2 [1–3]/3 [2–4]; P ≤ 0.05) and reduced artifacts significantly (P ≤ 0.05). The O-MAR processing increased sensitivity for bleeding by 160%. In some cases, new artifacts were induced through O-MAR processing, none of which impaired diagnostic image assessment. Discussion The investigated O-MAR algorithm reduces artifacts from DBS electrodes and should be used in the assessment of postoperative patients; however, combination with VMI does not provide an additional benefit. Received for publication December 7, 2017; and accepted for publication, after revision, January 24, 2018. Nils Große Hokamp and Alexandra Hellerbach contributed equally to this work. Conflicts of interest and sources of funding: DM received honoraria for talks outside this specific project from Philips. For NGH, AH, AG, DWJ, VVV, and SH, none declared. Supplemental digital contents are available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal's Web site (http://ift.tt/2kq7jVD). Correspondence to: Nils Große Hokamp, MD, Institute for Diagnostic and Interventional Radiology, University Hospital Cologne, Kerpener Str 62, 50937 Cologne, Germany. E-mail: nils.grosse-hokamp@uk-koeln.de. Copyright © 2018 Wolters Kluwer Health, Inc. All rights reserved.

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Soil uranium concentration at Ranger Uranium Mine Land Application Areas drives changes in the bacterial community

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Publication date: September 2018
Source:Journal of Environmental Radioactivity, Volume 189
Author(s): Saqib Mumtaz, Claire Streten, David L. Parry, Keith A. McGuinness, Ping Lu, Karen S. Gibb
Soil microorganisms may respond to metal stress by a shift in the microbial community from metal sensitive to metal resistant microorganisms. We assessed the bacterial community from low (2–20 mg kg−1), medium (200–400 mg kg−1), high (500–900 mg kg−1) and very high (>900 mg kg−1) uranium soils at Ranger Uranium Mine in northern Australia through pyrosequencing. Proteobacteria (28.85%) was the most abundant phylum at these sites, followed by Actinobacteria (9.31%), Acidobacteria (7.33%), Verrucomicrobia (2.11%), Firmicutes (2.02%), Chloroflexi (1.11%), Cyanobacteria (0.93%), Planctomycetes (0.82%), Bacteroidetes (0.46%) and Candidate_division_WS3 (Latescibacteria) (0.21%). However, 46.79% of bacteria were unclassified. Bacteria at low U soils differed from soils with elevated uranium. Bacterial OTUs closely related to Kitasatospora spp., Sphingobacteria spp. and Rhodobium spp. were only present at higher uranium concentrations and the bacterial community also changed with seasonal and temporal changes in soil uranium and physicochemical variables. This study using next generation sequencing in association with environmental variables at a uranium mine has laid a foundation for further studies of soil-microbe-metal interactions which may be useful for developing sustainable management and rehabilitation strategies. Furthermore, bacterial species associated with higher uranium may serve as useful indicators of uranium contamination in the wet-dry tropics.



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“X-Map 2.0” for Edema Signal Enhancement for Acute Ischemic Stroke Using Non–Contrast-Enhanced Dual-Energy Computed Tomography

Objectives A novel imaging technique ("X-map") has been developed to identify acute ischemic lesions for stroke patients using non–contrast-enhanced dual-energy computed tomography (NE-DE-CT). Using the 3-material decomposition technique, the original X-map ("X-map 1.0") eliminates fat and bone from the images, suppresses the gray matter (GM)-white matter (WM) tissue contrast, and makes signals of edema induced by severe ischemia easier to detect. The aim of this study was to address the following 2 problems with the X-map 1.0: (1) biases in CT numbers (or artifacts) near the skull of NE-DE-CT images and (2) large intrapatient and interpatient variations in X-map 1.0 values. Materials and Methods We improved both an iterative beam-hardening correction (iBHC) method and the X-map algorithm. The new iBHC (iBHC2) modeled x-ray physics more accurately. The new X-map ("X-map 2.0") estimated regional GM values—thus, maximizing the ability to suppress the GM-WM contrast, make edema signals quantitative, and enhance the edema signals that denote an increased water density for each pixel. We performed a retrospective study of 11 patients (3 men, 8 women; mean age, 76.3 years; range, 68-90 years) who presented to the emergency department with symptoms of acute stroke. Images were reconstructed with the old iBHC (iBHC1) and the iBHC2, and biases in CT numbers near the skull were measured. Both X-map 2.0 maps and X-map 1.0 maps were computed from iBHC2 images, both with and without a material decomposition-based edema signal enhancement (ESE) process. X-map values were measured at 5 to 9 locations on GM without infarct per patient; the mean value was calculated for each patient (we call it the patient-mean X-map value) and subtracted from the measured X-map values to generate zero-mean X-map values. The standard deviation of the patient-mean X-map values over multiple patients denotes the interpatient variation; the standard deviation over multiple zero-mean X-map values denotes the intrapatient variation. The Levene F test was performed to assess the difference in the standard deviations with different algorithms. Using 5 patient data who had diffusion weighted imaging (DWI) within 2 hours of NE-DE-CT, mean values at and near ischemic lesions were measured at 7 to 14 locations per patient with X-map images, CT images (low kV and high kV), and DWI images. The Pearson correlation coefficient was calculated between a normalized increase in DWI signals and either X-map or CT. Results The bias in CT numbers was lower with iBHC2 than with iBHC1 in both high- and low-kV images (2.5 ± 2.0 HU [95% confidence interval (CI), 1.3–3.8 HU] for iBHC2 vs 6.9 ± 2.3 HU [95% CI, 5.4–8.3 HU] for iBHC1 with high-kV images, P

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Detection of Subsolid Nodules in Lung Cancer Screening: Complementary Sensitivity of Visual Reading and Computer-Aided Diagnosis

Objectives The aim of this study was to compare computer-aided diagnosis (CAD) and visual reading for the detection of subsolid nodules (SSNs) in volumetrl measuremic low-dose computed tomography (LDCT) for lung cancer screening. Materials and Methods Prospective visual detection (VD) and manuaent of SSN were performed in the 2303 baseline volumetric LDCTs of the Multicenter Italian Lung Detection trial. Baseline and 2- and 4-year LDCTs underwent retrospective CAD analysis, subsequently reviewed by 2 experienced thoracic radiologists. The reference standard was defined by the cumulative number of SSNs detected by any reading method between VD and CAD. The number of false-positive CAD marks per scan (FPSSN/scan) was calculated. The positive predictive value of CAD was quantified per nodule (PPVSSN) and per screenee (PPVScreenee). The sensitivity and negative predictive value were compared between CAD and VD. The longitudinal 3-time-point sensitivity of CAD was calculated in the subgroup of persistent SSNs seen by VD (ratio between the prevalent SSNs detected by CAD through 3 time points and the total number of persistent prevalent SSNs detected by VD) to test the sensitivity of iterated CAD analysis during a screening program. Semiautomatic characteristics (diameter, volume, and mass; both for whole nodule and solid component) were compared between SSN detected CAD-only or VD-only to investigate whether either reading method could suffer from specific sensitivity weakness related to SSN features. Semiautomatic and manual diameters were compared using Spearman ρ correlation and Bland-Altman plot. Results Computer-aided diagnosis and VD detected a total of 194 SSNs in 6.7% (155/2,303) of screenees at baseline LDCT. The CAD showed mean FPSSN/scan of 0.26 (604/2,303); PPVSSN 22.5% (175/779) for any SSN, with 54.4% (37/68) for PSN and 19.4% for NSN (138/711; P

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Reduction of Artifacts Caused by Deep Brain Stimulating Electrodes in Cranial Computed Tomography Imaging by Means of Virtual Monoenergetic Images, Metal Artifact Reduction Algorithms, and Their Combination

Objectives The aim of this study was to evaluate the reduction of artifacts from deep brain stimulation electrodes (DBS) using an iterative metal artifact reduction algorithm (O-MAR), virtual monoenergetic images (VMI), and both in combination in postoperative spectral detector computed tomography using a dual-layer detector (spectral detector computed tomography [SDCT]) of the head. Material and Methods Nonanthropomorphic phantoms with different DBS leads were examined on SDCT; in 1 phantom periprocedural bleeding was simulated. A total of 20 patients who underwent SDCT after DBS implantation between October 2016 and April 2017 were included in this institutional review board–approved retrospective study. Images were reconstructed using standard-of-care iterative reconstruction (CI) and VMI, each with and without O-MAR processing (IR and MAR). Artifacts were quantified by determining the percentage integrity uniformity in an annular region of 1.4 cm2 around the DBS lead; a percentage integrity uniformity of 100% indicates the absence of artifacts. In phantoms, conspicuity of blood was determined on a binary scale, whereas in patients, image quality, DBS lead assessment, and extent of artifact reduction were assessed on Likert scales by 2 radiologists. Statistical significance was assessed using analysis of variance and Wilcoxon tests; sensitivity and specificity were calculated. Results The O-MAR processing significantly decreased artifacts in phantom and patients (P ≤ 0.05), whereas VMI did not reduce artifact burden compared with corresponding CI (P > 0.05): for example, CI-IR/MAR and 200 keV-IR/MAR for patients: 76.3%/90.7% and 75.9%/91.2%, respectively. Qualitatively, overall image quality was not improved (P > 0.05) and MAR improved DBS assessment (CI-IR/MAR: 2 [1–3]/3 [2–4]; P ≤ 0.05) and reduced artifacts significantly (P ≤ 0.05). The O-MAR processing increased sensitivity for bleeding by 160%. In some cases, new artifacts were induced through O-MAR processing, none of which impaired diagnostic image assessment. Discussion The investigated O-MAR algorithm reduces artifacts from DBS electrodes and should be used in the assessment of postoperative patients; however, combination with VMI does not provide an additional benefit. Received for publication December 7, 2017; and accepted for publication, after revision, January 24, 2018. Nils Große Hokamp and Alexandra Hellerbach contributed equally to this work. Conflicts of interest and sources of funding: DM received honoraria for talks outside this specific project from Philips. For NGH, AH, AG, DWJ, VVV, and SH, none declared. Supplemental digital contents are available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal's Web site (http://ift.tt/2kq7jVD). Correspondence to: Nils Große Hokamp, MD, Institute for Diagnostic and Interventional Radiology, University Hospital Cologne, Kerpener Str 62, 50937 Cologne, Germany. E-mail: nils.grosse-hokamp@uk-koeln.de. Copyright © 2018 Wolters Kluwer Health, Inc. All rights reserved.

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Assessment of right ventricular dysfunction in end-stage renal disease patients on maintenance haemodialysis by cardiac magnetic resonance imaging

Publication date: May 2018
Source:European Journal of Radiology, Volume 102
Author(s): Wanlin Peng, Zhenlin Li, Huayan Xu, Chunchao Xia, Yingkun Guo, Jinge Zhang, Keling Liu, Yuming Li, Jin Pu, Huapeng Zhang, Tianlei Cui
PurposeTo assess right ventricular (RV) dysfunction in end-stage renal disease (ESRD) patients on maintenance haemodialysis (HD) by cardiac magnetic resonance (CMR) imaging and determined the risk factors associated with RV dysfunction.Materials and methodsFifty ESRD patients on maintenance HD and 16 age- and gender-matched healthy individuals were prospectively enrolled and underwent CMR imaging. Left ventricular (LV) and RV function parameters, including end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV) and ejection fraction (EF), were measured and compared. Independent sample t-test and Mann–Whitney U-test were used to compare the differences between healthy individuals and ESRD patients. Pearson correlation and multiple linear regression analyses were used to assess risk factors associated with RV dysfunction.ResultsSignificantly lower RVEF and LVEF were observed in ESRD patients than in the control group (all p < 0.001). RVEDV, RVESV and RVSV in ESRD patients were also lower than those in the control group (all p < 0.05). Meanwhile, higher LVESV, LV mass and interventricular septum thickness were found in ESRD patients than in the control group (all p < 0.05). RVEF was positively correlated with LVEF (r = 0.37, p = 0.008) and negatively correlated with the duration of renal insufficiency (r = −0.53, p < 0.001) and dialysis (r = −0.63, p < 0.001). Moreover, multiple linear regression analyses revealed that the duration of dialysis and LVEF were independently associated with decreased RVEF (adjusted R2 = 0.53, p < 0.001).ConclusionsIn ESRD patients on maintenance HD, RV function was impaired and associated with the deterioration of LV function. More importantly, the duration of dialysis was considered as a risk factor independently associated with RV dysfunction.



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Radiology reporting—from Hemingway to HAL?

Abstract

The job of the diagnostic radiologist is two-fold: identifying and interpreting the information available from diagnostic imaging studies and communicating that interpretation meaningfully to the referring clinician. However skilled our interpretive abilities, our patients are not well served if we fail to convey our conclusions effectively. Despite the central importance of communication skills to the work of radiologists, trainees rarely receive significant formal training in reporting skills, and much of the training given simply reflects the trainer's personal preferences. Studies have shown a preference among referrers for reports in a structured form, with findings given in a standard manner, followed by a conclusion. The technical competence to incorporate structured report templates into PACS/RIS systems is growing, "...and radiology societies (including the European Society of Radiology (ESR)) are active in producing and validating templates for a wide range of modalities and clinical circumstances. While some radiologists may prefer prose format reports, and much literature has been produced addressing "dos and don'ts" for such prose reports, it seems likely that structured reporting will become the norm in the near future. Benefits will include homogenisation and standardisation of reports, certainty that significant information has not been omitted, and capacity for data-mining of structured reports for research and teaching purposes.

Teaching Points

• The radiologist's job includes interpretation of imaging studies AND communication.

• Traditionally, communication has taken the form of a prose report.

• Referrers have been shown to prefer reports in a structured format.

• Structured reports have many advantages over traditional prose reports.

• It is likely that structured reports represent the future standard.



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Pressure Mapping and Hemodynamic Assessment of Intracranial Dural Sinuses and Dural Arteriovenous Fistulas with 4D Flow MRI [ADULT BRAIN]

SUMMARY:

The feasibility of 4D flow MR imaging to visualize flow patterns and generate relative pressure maps in the dural venous sinus in healthy subjects (n = 60) and patients with dural arteriovenous fistulas (n = 7) was investigated. Dural venous drainage was classified based on torcular Herophili anatomy by using 4D flow MR imaging–derived angiograms and magnitude images. Subjects were scanned in a 3T clinical MR imaging system. 4D flow MR imaging enabled noninvasive characterization of dural sinus anatomy and mapping of relative pressure differences.



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Prenatal Factors Associated with Postnatal Brain Injury in Infants with Congenital Diaphragmatic Hernia [PEDIATRICS]

BACKGROUND AND PURPOSE:

Approximately 60% of infants with congenital diaphragmatic hernia have evidence of brain injury on postnatal MR imaging. It is unclear whether any brain injury is present before birth. In this study, we evaluated fetal MR imaging findings of brain injury and the association of congenital diaphragmatic hernia severity with postnatal brain injury.

MATERIALS AND METHODS:

Fetal MR imaging and postnatal brain MR imaging were retrospectively evaluated in 36 cases of congenital diaphragmatic hernia (from 2009 to 2014) by 2 pediatric neuroradiologists. Brain injury on postnatal MR imaging and brain injury and congenital diaphragmatic hernia severity on fetal MR imaging were recorded. Correlations between brain abnormalities on fetal and postnatal brain MR imaging were analyzed. Postnatal brain injury findings correlating with the severity of congenital diaphragmatic hernia were also assessed.

RESULTS:

On fetal MR imaging, enlarged extra-axial spaces (61%), venous sinus distention (21%), and ventriculomegaly (6%) were identified. No maturational delay, intracranial hemorrhage, or brain parenchymal injury was identified on fetal MR imaging. On postnatal MR imaging, 67% of infants had evidence of abnormality, commonly, enlarged extra-axial spaces (44%). Right-sided congenital diaphragmatic hernia was associated with a greater postnatal brain injury score (P = .05). Low observed-to-expected lung volume was associated with postnatal white matter injury (P = .005) and a greater postnatal brain injury score (P = .008). Lack of liver herniation was associated with normal postnatal brain MR imaging findings (P = .03).

CONCLUSIONS:

Fetal lung hypoplasia is associated with postnatal brain injury in congenital diaphragmatic hernia, suggesting that the severity of lung disease and associated treatments affect brain health as well. We found no evidence of prenatal brain parenchymal injury or maturational delay.



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Beware of Multiphase CTA Interpretation [letter]



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Expression Changes in Lactate and Glucose Metabolism and Associated Transporters in Basal Ganglia following Hypoxic-Ischemic Reperfusion Injury in Piglets [PEDIATRICS]

BACKGROUND AND PURPOSE:

The neonatal brain has active energy metabolism, and glucose oxidation is the major energy source of brain tissue. Lactate is produced by astrocytes and released to neurons. In the central nervous system, lactate is transported between neurons and astrocytes via the astrocyte-neuron lactate shuttle. The aim of this study was to investigate the regulatory mechanisms of energy metabolism in neurons and astrocytes in the basal ganglia of a neonatal hypoxic-ischemic brain injury piglet model.

MATERIALS AND METHODS:

A total of 35 healthy piglets (3–5 days of age; 1.0–1.5 kg) were assigned to a control group (n = 5) or a hypoxic-ischemic model group (n = 30). The hypoxic-ischemic model group was further divided into 6 groups according to the 1H-MR spectroscopy and PET/CT scan times after hypoxia-ischemia (0–2, 2–6, 6–12, 12–24, 24–48, and 48–72 hours; n = 5/group). 1H-MR spectroscopy data were processed with LCModel software. Maximum standard uptake values refer to the maximum standard uptake values for glucose (or FDG). The maximum standard uptake values of the basal ganglia–to-occipital cortex ratio were analyzed. The expression levels of glucose transporters and monocarboxylate transporters were detected by immunohistochemical analysis.

RESULTS:

Lactate levels decreased after an initial increase, with the maximal level occurring around 2–6 hours following hypoxia-ischemia. After hypoxia-ischemia, the maximum standard uptake values of the basal ganglia and basal ganglia/occipital cortex initially increased then decreased, with the maximum occurring at approximately 6–12 hours. The lactate and glucose uptake (basal ganglia/occipital cortex maximum standard uptake values) levels were positively correlated. The expression levels of glucose transporter-1 and glucose transporter-3 were positively correlated with the basal ganglia/occipital cortex. The expression levels of monocarboxylic acid transporter-2 and monocarboxylic acid transporter-4 were positively correlated with lactate content.

CONCLUSIONS:

The results indicate that lactate and glucose transporters have a synergistic effect on the energy metabolism of neurons and astrocytes following hypoxic-ischemic reperfusion brain injury.



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MR Imaging Criteria for the Detection of Nasopharyngeal Carcinoma: Discrimination of Early-Stage Primary Tumors from Benign Hyperplasia [HEAD & NECK]

BACKGROUND AND PURPOSE:

MR imaging can detect nasopharyngeal carcinoma that is hidden from endoscopic view, but for accurate detection carcinoma confined within the nasopharynx (stage T1) must be distinguished from benign hyperplasia of the nasopharynx. This study aimed to document the MR imaging features of stage T1 nasopharyngeal carcinoma and to attempt to identify features distinguishing it from benign hyperplasia.

MATERIALS AND METHODS:

MR images of 189 patients with nasopharyngeal carcinoma confined to the nasopharynx and those of 144 patients with benign hyperplasia were reviewed and compared in this retrospective study. The center, volume, size asymmetry (maximum percentage difference in area between the right and left nasopharyngeal halves), signal intensity asymmetry, deep mucosal white line (greater contrast enhancement along the deep tumor margin), and absence/distortion of the adenoidal septa were evaluated. Differences were assessed with logistic regression and the 2 test.

RESULTS:

The nasopharyngeal carcinoma center was lateral, central, or diffuse in 134/189 (70.9%), 25/189 (13.2%), and 30/189 (15.9%) cases, respectively. Nasopharyngeal carcinomas involving the walls showed that a deep mucosal white line was present in 180/183 (98.4%), with a focal loss of this line in 153/180 (85%) cases. Adenoidal septa were absent or distorted in 111/111 (100%) nasopharyngeal carcinomas involving the adenoid. Compared with benign hyperplasia, nasopharyngeal carcinoma had a significantly greater volume, size asymmetry, signal asymmetry, focal loss of the deep mucosal white line, and absence/distortion of the adenoidal septa (P < .001). Although size asymmetry was the most accurate criterion (89.5%) for nasopharyngeal carcinoma detection, use of this parameter alone would have missed 11.9% of early-stage T1 nasopharyngeal carcinomas.

CONCLUSIONS:

MR imaging features can help distinguish stage T1 nasopharyngeal carcinoma from benign hyperplasia in most cases.



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Spinal Angiogram: A Treacherous Criterion Standard... [letter]



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Quantitative Analysis of Conebeam CT for Delineating Stents in Stent-Assisted Coil Embolization [INTERVENTIONAL]

BACKGROUND AND PURPOSE:

Innovative techniques and device-related advances have improved the outcomes of neuroendovascular treatment. 3D imaging has previously used 2 x 2 binning, but 1 x 1 binning has recently been made available. The aim of this study was to evaluate the quantitative ability of conebeam CT for stent delineation and to investigate its effectiveness in the clinical environment.

MATERIALS AND METHODS:

Four acquisition groups of 3D MIP images acquired using conebeam CT with varying conditions (acquisition time, 10 or 20 seconds and binning, 1 x 1 or 2 x 2) were compared. Two methods of analysis were performed, a phantom study and an analysis of 28 randomly selected patients. The phantom study assessed the contrast-to-noise ratio and full width at half maximum values in conebeam CT images of intracranial stent struts. In the clinical subjects, we assessed contrast-to-noise ratio, full width at half maximum, and dose-area product.

RESULTS:

In the phantom study, the contrast-to-noise ratio was not considerably different between 10- and 20-second acquisition times at equivalent binning settings. Additionally, the contrast-to-noise ratio at equivalent acquisition times did not differ considerably by binning setting. For the full width at half maximum results, equivalent acquisition times differed significantly by binning setting. In the clinical analyses, the 10-second/1 x 1 group (versus 20 second/2 x 2) showed a higher contrast-to-noise ratio (P < .05) and a dose-area product reduced by approximately 70% (P < .05), but the difference in full width at half maximum was not significant (P = .20).

CONCLUSIONS:

For stent-assisted coil embolization, quantitative assessment of conebeam CT showed that 10 second/1 x 1 was equivalent to 20 second/2 x 2 for imaging deployed intracranial stents. Furthermore, the 10-second/1 x 1 settings resulted in a much smaller DAP.



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Imaging of Anaplastic Thyroid Carcinoma [HEAD & NECK]

SUMMARY:

Anaplastic thyroid carcinoma is fatal if unresectable. However, improved survival has been reported after gross total resection and multimodality therapy. In this report, we describe the contrast-enhanced high-resolution CT characteristics of anaplastic thyroid carcinoma in 57 patients. Anaplastic thyroid carcinoma presented as a large neck mass with necrosis in 82% of cases. The tumors demonstrated common extrathyroidal extension (91%). Sixty-two percent of tumors demonstrated calcification. Visceral space invasion involved the esophagus (62%), trachea (57%), and larynx (29%). Carotid artery encasement was present in 42%, and 43% involved the internal jugular vein. Sixty-three percent had lateral compartment lymphadenopathy; 58% of these nodes were necrotic, and 11% were cystic. No metastatic nodes had calcification. Central compartment lymphadenopathy was seen in 56% of cases, and lateral retropharyngeal lymphadenopathy was detected in 12%. Knowledge of these imaging features aids in guiding the approach to the initial tissue diagnosis with either fine-needle aspiration or core biopsy, assessing the feasibility of surgical resection, and determining prognosis.



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Spinal Arteriovenous Vascular Malformations in Patients with Neural Tube Defects [SPINE]

BACKGROUND AND PURPOSE:

Neural tube defects, such as tethered cord, intradural lipoma, or myelomeningocele may coexist with spinal vascular malformations. The coexistence of these 2 rare entities is suggestive of a causal relationship between them, which may lead to further understanding of their pathogenesis. We present a series of 6 patients with epidural spinal arteriovenous fistulas associated with neural tube defects.

MATERIALS AND METHODS:

We retrieved cases of spinal vascular malformations associated with neural tube defects seen at our institution. The clinical presentation, MR imaging/MRA and angiographic imaging, treatment outcomes, and long-term neurologic outcomes were analyzed. Descriptive statistical analyses are reported.

RESULTS:

Six patients with epidural arteriovenous fistulas and neural tube defects were included in this study. The mean age at presentation was 42 years, and the most common presenting symptoms were lower extremity weakness followed by sensory disturbances and bladder/bowel dysfunction. In most cases (5/6), the fistulas were located at the sacral level. All cases were fed by the lateral sacral artery (6/6). Four patients had prior spine surgery, but the fistula was in the operative bed in 2 cases. All fistulas were extradural with secondary intradural venous drainage. Five patients underwent transarterial embolization with Onyx, and 1 patient had a treatment-related complication.

CONCLUSIONS:

It is conceivable that there is a pathophysiologic link between neural tube defects and development of spinal vascular malformations. Delayed neurologic deterioration or high conus signal in a patient with a neural tube defect should suggest the possibility of such an association.



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[other]



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Nonsphericity Index and Size Ratio Identify Morphologic Differences between Growing and Stable Aneurysms in a Longitudinal Study of 93 Cases [INTERVENTIONAL]

BACKGROUND AND PURPOSE:

Recent studies have strongly associated intracranial aneurysm growth with increased risk of rupture. Identifying aneurysms that are likely to grow would be beneficial to plan more effective monitoring and intervention strategies. Our hypothesis is that for unruptured intracranial aneurysms of similar size, morphologic characteristics differ between aneurysms that continue to grow and those that do not.

MATERIALS AND METHODS:

From aneurysms in our medical center with follow-up imaging dates in 2015, ninety-three intracranial aneurysms (23 growing, 70 stable) were selected. All CTA images for the aneurysm diagnosis and follow-up were collected, a total of 348 3D imaging studies. Aneurysm 3D geometry for each imaging study was reconstructed, and morphologic characteristics, including volume, surface area, nonsphericity index, aspect ratio, and size ratio were calculated.

RESULTS:

Morphologic characteristics were found to differ between growing and stable groups. For aneurysms of <3 mm, nonsphericity index (P < .001); 3–5 mm, nonsphericity index (P < .001); 5–7 mm, size ratio (P = .003); >7 mm, volume (P < .001); surface area (P < .001); and nonsphericity index (P = .002) were significant. Within the anterior communicating artery, the nonsphericity index (P = .008) and, within the posterior communicating artery, size ratio (P = .004) were significant. The nonsphericity index receiver operating characteristic area under the curve was 0.721 for discriminating growing and stable cases on the basis of initial images.

CONCLUSIONS:

Among aneurysms with similar sizes, morphologic characteristics appear to differ between those that are growing and those that are stable. The nonsphericity index, in particular, was found to be higher among growing aneurysms. The size ratio was found to be the second most significant parameter associated with growth.



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Blunt Cerebrovascular Injuries: Advances in Screening, Imaging, and Management Trends [review-article]

SUMMARY:

Blunt cerebrovascular injury is a relatively uncommon but sometimes life-threatening injury, particularly in patients presenting with ischemic symptoms in that vascular territory. The decision to pursue vascular imaging (generally CT angiography) is based on clinical and imaging findings. Several grading scales or screening criteria have been developed to guide the decision to pursue vascular imaging, as well as to recommend different treatment options for various injuries. The data supporting many of these guidelines and options are limited however. The purpose of this article is to review and compare these scales and criteria and the data supporting clinical efficacy and to make recommendations for future research in this area.



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MR Imaging-Based Evaluations of Olfactory Bulb Atrophy in Patients with Olfactory Dysfunction [HEAD & NECK]

BACKGROUND AND PURPOSE:

Although the olfactory bulb volume as assessed with MR imaging is known to reflect olfactory function, it is not always measured during olfactory pathway assessments in clinical settings. We aimed to evaluate the utility of visual olfactory bulb atrophy and neuropathy analyses using MR imaging in patients with olfactory dysfunction.

MATERIALS AND METHODS:

Thirty-four patients who presented with subjective olfactory loss between March 2016 and February 2017 were included. Patients underwent a nasal endoscopic examination, olfactory testing with the Korean Version of the Sniffin' Sticks test, and MR imaging. All patients completed the Sino-Nasal Outcome Test and Questionnaire of Olfactory Disorders. Olfactory bulb atrophy and neuropathy were evaluated on MR images by 2 head and neck radiologists.

RESULTS:

The etiology of olfactory loss was chronic rhinosinusitis with/without nasal polyps in 15 (44.1%) patients, respiratory viral infection in 7 (20.6%), trauma in 2 (5.9%), and idiopathic in 10 (29.4%) patients. Although 10 (29.4%) of the 34 patients were normosmic according to the Sniffin' Sticks test, their scores on the other tests were like those of patients who were hyposmic/anosmic according to the Sniffin' Sticks test. However, the detection rate of olfactory bulb atrophy was significantly higher in patients with hyposmia/anosmia than it was in patients with normosmia (P = .002). No difference in olfactory bulb neuropathy was identified among patients with normosmia and hyposmia/anosmia (P = .395).

CONCLUSIONS:

MR imaging evaluations of olfactory bulb atrophy can be used to objectively diagnose olfactory dysfunction in patients with subjective olfactory loss.



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Development of High Signal Intensity within the Globus Pallidus and Dentate Nucleus following Multiple Administrations of Gadobenate Dimeglumine [PATIENT SAFETY]

BACKGROUND AND PURPOSE:

Previous studies have evaluated various gadolinium based contrast agents and their association with gadolinium retention, however, there is a discrepancy in the literature concerning the linear agent gadobenate dimeglumine. Our aim was to determine whether an association exists between the administration of gadobenate dimeglumine and the development of intrinsic T1-weighted signal in the dentate nucleus and globus pallidus.

MATERIALS AND METHODS:

In this single-center, retrospective study, the signal intensity of the globus pallidus, dentate nucleus, thalamus, and middle cerebellar peduncle was measured on unenhanced T1-weighted images in 29 adult patients who had undergone multiple contrast MRIs using exclusively gadobenate dimeglumine (mean, 10.1 ± 3.23 doses; range, 6–18 doses). Two neuroradiologists, blinded to the number of prior gadolinium-based contrast agent administrations, separately placed ROIs within the globi pallidi, thalami, dentate nuclei, and middle cerebellar peduncles on the last MR imaging examinations. The correlations between the globus pallidus:thalamus and the dentate nucleus:middle cerebellar peduncle signal intensity ratios with the number of gadolinium-based contrast agent administrations and cumulative dose were tested with either 1-tailed Pearson or Spearman correlations. A priori, P < .05 was considered statistically significant.

RESULTS:

Both the globus pallidus:thalamus and dentate nucleus:middle cerebellar peduncle ratios showed significant correlation with the number of gadolinium-based contrast agent administrations (r = 0.39, P = .017, and r = 0.58, P = .001, respectively). Additionally, the globus pallidus:thalamus and dentate nucleus:middle cerebellar peduncle ratios showed significant correlation with the cumulative dose of gadobenate dimeglumine (r = 0.48, P = .004, and r = 0.43, P = .009, respectively). Dentate nucleus hyperintensity was qualitatively present on the last MR imaging in 79.3%–86.2% of patients and in all patients who had received >10 doses.

CONCLUSIONS:

At high cumulative doses (commonly experienced by patients, for example, with neoplastic disease), gadobenate dimeglumine is associated with an increase in the globus pallidus:thalamus and dentate nucleus:middle cerebellar peduncles signal intensity ratios.



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High Signal Intensity in the Dentate Nucleus and Globus Pallidus on Unenhanced T1-Weighted MR Images: Comparison between Gadobutrol and Linear Gadolinium-Based Contrast Agents [PATIENT SAFETY]

BACKGROUND AND PURPOSE:

In view of the recent observations that gadolinium deposits in brain tissue after intravenous injection, our aim of this study was to compare signal changes in the globus pallidus and dentate nucleus on unenhanced T1-weighted MR images in patients receiving serial doses of gadobutrol, a macrocyclic gadolinium-based contrast agent, with those seen in patients receiving linear gadolinium-based contrast agents.

MATERIALS AND METHODS:

This was a retrospective analysis of on-site patients with brain tumors. Fifty-nine patients received only gadobutrol, and 60 patients received only linear gadolinium-based contrast agents. Linear gadolinium-based contrast agents included gadoversetamide, gadobenate dimeglumine, and gadodiamide. T1 signal intensity in the globus pallidus, dentate nucleus, and pons was measured on the precontrast portions of patients' first and seventh brain MRIs. Ratios of signal intensity comparing the globus pallidus with the pons (globus pallidus/pons) and dentate nucleus with the pons (dentate nucleus/pons) were calculated. Changes in the above signal intensity ratios were compared within the gadobutrol and linear agent groups, as well as between groups.

RESULTS:

The dentate nucleus/pons signal ratio increased in the linear gadolinium-based contrast agent group (t = 4.215, P < .001), while no significant increase was seen in the gadobutrol group (t = –1.422, P = .08). The globus pallidus/pons ratios followed similarly, with an increase in the linear gadolinium-based contrast agent group (t = 2.931, P < .0001) and no significant change in those receiving gadobutrol (t = 0.684, P = .25).

CONCLUSIONS:

Successive doses of gadobutrol do not result in T1 shortening compared with changes seen in linear gadolinium-based contrast agents.



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Looking Deep into the Eye-of-the-Tiger in Pantothenate Kinase-Associated Neurodegeneration [PEDIATRICS]

BACKGROUND AND PURPOSE:

A detailed delineation of the MR imaging changes in the globus pallidus in pantothenate kinase–associated neurodegeneration will be helpful for diagnosis and monitoring of patients. The aim of this study was to determine the morphologic spectrum of the "eye-of-the-tiger" sign and the topographic pattern of iron deposition in a group of patients with pantothenate kinase–associated neurodegeneration.

MATERIALS AND METHODS:

Seventy-four MR imaging scans from 54 individuals with PANK2 mutations were analyzed for signal patterns in the globus pallidus. Sixteen SWI data from 15 patients who underwent 1.5T (n = 7), 3T (n = 7), and 7T (n = 2) MR imaging were included to visualize the iron topography.

RESULTS:

The linear hyperintensity alongside the medial border of the globus pallidus was the earliest T2 signal change. This finding was evident before SWI changes from iron deposition became visible. T2WI performed in early childhood mostly showed isolated hyperintense signal. In adult patients, marked signal reduction within an earlier hyperintense center resulting from iron accumulation led to the loss of signal difference between the central and surrounding areas. Signal hypointensity on SWI progressed from the medial to the lateral portion of the globus pallidus with increasing age. The fiber connections between the medial globus pallidus and the anteromedial aspect of the substantia nigra and subthalamic nucleus were markedly hypointense on SWI.

CONCLUSIONS:

In pantothenate kinase–associated neurodegeneration, the globus pallidus MR imaging changes using SWI develop as region-specific and age-dependent phenomena. Signal inhomogeneity was observed across the globus pallidus in pantothenate kinase–associated neurodegeneration and should be considered when determining the concentration of iron.



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Cerebral Mitochondrial Microangiopathy Leads to Leukoencephalopathy in Mitochondrial Neurogastrointestinal Encephalopathy [ADULT BRAIN]

BACKGROUND AND PURPOSE:

Mitochondrial neurogastrointestinal encephalopathy is a rare disorder due to recessive mutations in the thymidine phosphorylase gene, encoding thymidine phosphorylase protein required for mitochondrial DNA replication. Clinical manifestations include gastrointestinal dysmotility and diffuse asymptomatic leukoencephalopathy. This study aimed to elucidate the mechanisms underlying brain leukoencephalopathy in patients with mitochondrial neurogastrointestinal encephalopathy by correlating multimodal neuroradiologic features to postmortem pathology.

MATERIALS AND METHODS:

Seven patients underwent brain MR imaging, including single-voxel proton MR spectroscopy and diffusion imaging. Absolute concentrations of metabolites calculated by acquiring unsuppressed water spectra at multiple TEs, along with diffusion metrics based on the tensor model, were compared with those of healthy controls using unpaired t tests in multiple white matters regions. Brain postmortem histologic, immunohistochemical, and molecular analyses were performed in 1 patient.

RESULTS:

All patients showed bilateral and nearly symmetric cerebral white matter hyperintensities on T2-weighted images, extending to the cerebellar white matter and brain stem in 4. White matter, N-acetylaspartate, creatine, and choline concentrations were significantly reduced compared with those in controls, with a prominent increase in the radial water diffusivity component. At postmortem examination, severe fibrosis of brain vessel smooth muscle was evident, along with mitochondrial DNA replication depletion in brain and vascular smooth-muscle and endothelial cells, without neuronal loss, myelin damage, or gliosis. Prominent periependymal cytochrome C oxidase deficiency was also observed.

CONCLUSIONS:

Vascular functional and histologic alterations account for leukoencephalopathy in mitochondrial neurogastrointestinal encephalopathy. Thymidine toxicity and mitochondrial DNA replication depletion may induce microangiopathy and blood-brain-barrier dysfunction, leading to increased water content in the white matter. Periependymal cytochrome C oxidase deficiency could explain prominent periventricular impairment.



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Concerns about a New Preterm MR Imaging Scoring System [letter]



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Cerebellar Hypoperfusion in Migraine Attack: Incidence and Significance [ADULT BRAIN]

BACKGROUND AND PURPOSE:

Patients diagnosed with migraine with aura have an increased lifetime risk of ischemic stroke. It is not yet clear whether prolonged cortical hypoperfusion during an aura increases the immediate risk of cerebellar infarction because it may induce crossed cerebellar diaschisis and subsequent tissue damage. To address this question, we retrospectively analyzed potential relationships between cortical oligemia and cerebellar hypoperfusion in patients with migraine with aura and their potential relation to small infarct-like cerebellar lesions.

MATERIALS AND METHODS:

One hundred six migraineurs who underwent MR imaging, including DSC perfusion, were included in the study. In patients with apparent perfusion asymmetry, we used ROI analysis encompassing 18 infra- and supratentorial ROIs to account for differences in regional cerebral blood flow and volume. The presence of cerebellar hypoperfusion was calculated using an asymmetry index, with values of >10% being considered significant.

RESULTS:

We observed perfusion asymmetries in 23/106 patients, 22 in patients with migraine with aura (20.8%). Cerebellar hypoperfusion was observed in 12/23 patients (52.2%), and crossed cerebellar diaschisis, in 9/23 patients (39.1%) with abnormal perfusion. In none of the 106 patients were DWI restrictions observed during migraine with aura.

CONCLUSIONS:

Cerebellar hypoperfusion and crossed cerebellar diaschisis are common in patients with migraine with aura and cortical perfusion abnormalities. Crossed cerebellar diaschisis in migraine with aura may be considered a benign phenomenon because we observed no association with DWI restriction or manifest cerebellar infarctions, even in patients with prolonged symptom-related perfusion abnormalities persisting for up to 24 hours.



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Diagnostic Radiology Resident Recruitment Part I

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Publication date: Available online 12 March 2018
Source:Academic Radiology
Author(s): Mark E. Mullins, Arash Anavim, Lori A. Deitte, Theresa C. McLoud, Charles S. Resnik
To the best of our knowledge, there is little available organized advice for diagnostic radiology residency program directors and their programs regarding resident recruitment. We are a group of current and former program directors who are current vice chairs for education and continue to advise and to mentor many educators. We have constructed this article along the yearly schedule of trainee recruitment, including an application review, interviews, and troublesome trends that we have observed.



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Dentate Nucleus Signal Intensity Decrease on T1-weighted MR Images after Switching from Gadopentate Dimeglumine to Gadobutrol.

Dentate Nucleus Signal Intensity Decrease on T1-weighted MR Images after Switching from Gadopentate Dimeglumine to Gadobutrol.

Radiology. 2018 Mar 14;:171398

Authors: Behzadi AH, Farooq Z, Zhao Y, Shih G, Prince MR

Abstract
Purpose To determine if the increased dentate nucleus signal intensity following six or more doses of a linear gadolinium-based contrast agent (GBCA) (gadopentetate dimeglumine) changes at follow-up examinations performed with a macrocyclic GBCA (gadobutrol). Materials and Methods This retrospective study included 13 patients with increased dentate nucleus signal intensity following at least six (range, 6-18) gadopentetate dimeglumine administrations who then underwent at least 12 months of follow-up imaging with multiple (range, 3-29) gadobutrol-enhanced magnetic resonance (MR) examinations. Dentate nucleus-to-pons and dentate nucleus-to-cerebellar peduncle signal intensity ratios were measured by two radiologists blinded to all patient information, and changes were analyzed by using the paired t test and linear regression. Results The mean dentate nucleus-to-pons and dentate nucleus-to-cerebellar peduncle signal intensity ratios increased after gadopentetate dimeglumine administration, from 0.98 ± 0.03 to 1.10 ± 0.03 (P < .0001) and from 0.98 ± 0.030 to 1.09 ± 0.02 (P < .0001), respectively. With gadobutrol, the mean dentate nucleus-to-pons and dentate nucleus-to-cerebellar peduncle signal intensity ratios decreased to 1.03 ± 0.03 and 1.02 ± 0.04, respectively (P < .0001). With use of a mixed effects model linear regression allowing for each patient to have a different y intercept, mean dentate nucleus-to-pons and dentate nucleus-to-cerebellar peduncle signal intensity ratios decreased with follow-up time (dentate nucleus-to-pons: slope = -0.2% per month [95% confidence interval: -0.0024, -0.0015], R2 = 0.58, P < .0001 for nonzero slope; dentate nucleus-to-cerebellar peduncle: slope = -0.2% per month [95% confidence interval: -0.0024, -0.0015], R2 = 0.61, P < .0001 for nonzero slope). Conclusion Dentate signal intensity increased with at least six gadopentetate dimeglumine-enhanced MR examinations and decreased after switching from a linear (gadopentetate dimeglumine) to a macrocyclic (gadobutrol) GBCA. © RSNA, 2018 Online supplemental material is available for this article.

PMID: 29533723 [PubMed - as supplied by publisher]



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Computer-aided Volumetry of Part-Solid Lung Cancers by Using CT: Solid Component Size Predicts Prognosis.

Computer-aided Volumetry of Part-Solid Lung Cancers by Using CT: Solid Component Size Predicts Prognosis.

Radiology. 2018 Mar 14;:172319

Authors: Kamiya S, Iwano S, Umakoshi H, Ito R, Shimamoto H, Nakamura S, Naganawa S

Abstract
Purpose To investigate the relationship between the postoperative prognosis of patients with part-solid non-small cell lung cancer and the solid component size acquired by using three-dimensional (3D) volumetry software on multidetector computed tomographic (CT) images. Materials and Methods A retrospective study by using preoperative multidetector CT data with 0.5-mm section thickness, clinical records, and pathologic reports of 96 patients with primary subsolid non-small cell lung cancer (47 men and 49 women; mean age ± standard deviation, 66 years ± 8) were reviewed. Two radiologists measured the two-dimensional (2D) maximal solid size of each nodule on an axial image (hereafter, 2D MSSA), the 3D maximal solid size on multiplanar reconstructed images (hereafter, 3D MSSMPR), and the 3D solid volume of greater than 0 HU (hereafter, 3D SV0HU) within each nodule. The correlations between the postoperative recurrence and the effects of clinical and pathologic characteristics, 2D MSSA, 3D MSSMPR, and 3D SV0HU as prognostic imaging biomarkers were assessed by using a Cox proportional hazards model. Results For the prediction of postoperative recurrence, the area under the receiver operating characteristics curve was 0.796 (95% confidence interval: 0.692, 0.900) for 2D MSSA, 0.776 (95% confidence interval: 0.667, 0.886) for 3D MSSMPR, and 0.835 (95% confidence interval: 0.749, 0.922) for 3D SV0HU. The optimal cutoff value for 3D SV0HU for predicting tumor recurrence was 0.54 cm3, with a sensitivity of 0.933 (95% confidence interval: 0.679, 0.998) and a specificity of 0.716 (95% confidence interval: 0.605, 0.811) for the recurrence. Significant predictive factors for disease-free survival were 3D SV0HU greater than or equal to 0.54 cm3 (hazard ratio, 6.61; P = .001) and lymphatic and/or vascular invasion derived from histopathologic analysis (hazard ratio, 2.96; P = .040). Conclusion The measurement of 3D SV0HU predicted the postoperative prognosis of patients with part-solid lung cancer more accurately than did 2D MSSA and 3D MSSMPR. © RSNA, 2018.

PMID: 29533722 [PubMed - as supplied by publisher]



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Prediction of Response to Neoadjuvant Chemotherapy and Radiation Therapy with Baseline and Restaging 18F-FDG PET Imaging Biomarkers in Patients with Esophageal Cancer.

Prediction of Response to Neoadjuvant Chemotherapy and Radiation Therapy with Baseline and Restaging 18F-FDG PET Imaging Biomarkers in Patients with Esophageal Cancer.

Radiology. 2018 Mar 14;:172229

Authors: Beukinga RJ, Hulshoff JB, Mul VEM, Noordzij W, Kats-Ugurlu G, Slart RHJA, Plukker JTM

Abstract
Purpose To assess the value of baseline and restaging fluorine 18 (18F) fluorodeoxyglucose (FDG) positron emission tomography (PET) radiomics in predicting pathologic complete response to neoadjuvant chemotherapy and radiation therapy (NCRT) in patients with locally advanced esophageal cancer. Materials and Methods In this retrospective study, 73 patients with histologic analysis-confirmed T1/N1-3/M0 or T2-4a/N0-3/M0 esophageal cancer were treated with NCRT followed by surgery (Chemoradiotherapy for Esophageal Cancer followed by Surgery Study regimen) between October 2014 and August 2017. Clinical variables and radiomic features from baseline and restaging 18F-FDG PET were selected by univariable logistic regression and least absolute shrinkage and selection operator. The selected variables were used to fit a multivariable logistic regression model, which was internally validated by using bootstrap resampling with 20 000 replicates. The performance of this model was compared with reference prediction models composed of maximum standardized uptake value metrics, clinical variables, and maximum standardized uptake value at baseline NCRT radiomic features. Outcome was defined as complete versus incomplete pathologic response (tumor regression grade 1 vs 2-5 according to the Mandard classification). Results Pathologic response was complete in 16 patients (21.9%) and incomplete in 57 patients (78.1%). A prediction model combining clinical T-stage and restaging NCRT (post-NCRT) joint maximum (quantifying image orderliness) yielded an optimism-corrected area under the receiver operating characteristics curve of 0.81. Post-NCRT joint maximum was replaceable with five other redundant post-NCRT radiomic features that provided equal model performance. All reference prediction models exhibited substantially lower discriminatory accuracy. Conclusion The combination of clinical T-staging and quantitative assessment of post-NCRT 18F-FDG PET orderliness (joint maximum) provided high discriminatory accuracy in predicting pathologic complete response in patients with esophageal cancer. © RSNA, 2018 Online supplemental material is available for this article.

PMID: 29533721 [PubMed - as supplied by publisher]



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Advantages of submandibular gland preservation surgery over submandibular gland resection for proximal submandibular stones.

Advantages of submandibular gland preservation surgery over submandibular gland resection for proximal submandibular stones.

Oral Surg Oral Med Oral Pathol Oral Radiol. 2017 Dec 29;:

Authors: Xiao JQ, Sun HJ, Qiao QH, Bao X, Wu CB, Zhou Q

Abstract
OBJECTIVES: This study sought to compare surgical outcomes after the removal of submandibular gland (SMG) stones via 2 different surgical methods.
MATERIALS AND METHODS: From June 2015 to July 2016, a total of 40 patients with SMG stones were selected from the Department of Oral and Maxillofacial Surgery, School of Stomatology, China Medical University (Shenyang, China), and were randomly assigned to 2 groups. Twenty patients underwent sialendoscopy-assisted stone removal via extraoral incision with preservation of the SMG, and 20 patients underwent traditional SMG resection. The outcomes of the 2 surgical procedures were assessed.
RESULTS: The operation time and hospital stay were shorter in the SMG preservation group than the SMG resection group. There were no significant differences in stone size or location between the groups. The mean visual analog scale (VAS) score was lower in the SMG preservation group than the SMG resection group. All patients in the SMG resection group exhibited varying degrees of scarring and concave deformity on the face and neck, whereas all patients in the SMG preservation group retained intact facial morphology.
CONCLUSIONS: Sialendoscopy-assisted stone removal with preservation of the SMG exhibited many advantages relative to traditional SMG resection.

PMID: 29530607 [PubMed - as supplied by publisher]



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Common trunk of the posterior intercostal arteries from the thoracic aorta: anatomical variation, frequency, and importance in individuals.

Common trunk of the posterior intercostal arteries from the thoracic aorta: anatomical variation, frequency, and importance in individuals.

Surg Radiol Anat. 2018 Mar 12;:

Authors: Kocbek L, Rakuša M

Abstract
PURPOSE: A common trunk of the posterior intercostal arteries originating from the descending thoracic aorta is normally an anatomical variation. A search through the literature disclosed the frequencies of common trunks variations among population, but no information relates to particular topic of simultaneous multiple common trunks of the PIA present in individuals.
METHODS: A total of 396 intercostal spaces were dissected in 44 cadavers from the vertebral body to the mid-axillary line to observe a common trunk of the paired posterior intercostal artery at the level from T2 to T11 intercostal space.
RESULTS: In 31 cadavers (70%), a common trunk of posterior intercostal arteries arising from descending thoracic aorta was visualed and 22 of those (71%) had two or more common trunks simultaneously present.
CONCLUSIONS: It is important to recognize this anatomical variation when the number of origins of the posterior intercostal arteries from the thoracic aorta due to the multiple common trunk present can be reduced, as their origins and vascular territories are involved in primary diseases of the thoracic aorta, like atherosclerosis, aneurysm, or dissection that lead to serious complications. For example, in thoracoabdominal aneurysm repair, reimplantation of the posterior intercostal arteries is recommended to avoid potential ischemic injury to the supplying areas, especially to the spinal cord.

PMID: 29532168 [PubMed - as supplied by publisher]



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