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Πέμπτη, 17 Αυγούστου 2017

PRIMARY INTRAOSSEOUS LEIOMYOSARCOMA OF THE MANDIBLE: CASE REPORT AND LITERATURE REVIEW

Primary leiomyosarcoma (LMS) is a rare type of malignant spindle cell tumor which arises from smooth muscle fibers. It is very uncommon in the oral cavity and only accounts for 4% of all soft tissue sarcomas in head and neck area, with intraosseous presentation even more rare. In this report, we present a new case of primary intraosseous LMS of the mandible and review the literature for previously reported cases. A 19-year-old female presented with an asymptomatic well defined radiolucent lesion of the right body of the mandible.

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ORAL HAIRY LEUKOPLAKIA AS A PREDOMINANTLY HIV-NEGATIVE ENTITY: A CASE SERIES

We present a case series of oral hairy leukoplakia (OHL), an oral mucosal lesion caused by Epstein-Barr virus (EBV) that is classically seen on the lateral tongue in patients with HIV/AIDS. We report on the features of OHL seen in the University of Pittsburgh Oral Pathology Biopsy Service and Medical Center.

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ODONTOAMELOBLASTOMA: A CASE REPORT AND REVIEW OF THE LITERATURE

Odontoameloblastoma (OA) is a rare mixed odontogenic tumor with both ameloblastic (epithelial) and odontoma-like (ectomesenchymal) features. It presents as a unilocular or multilocular radiolucent to mixed lesion with root resorption, boney expansion, and/or jaw pain. Microscopically, the epithelial component often resembles a follicular or plexiform variant of a conventional ameloblastoma. In contrast to an ameloblastoma, however, the surrounding mesenchyme consists of dental hard tissue in the form of a compound or complex odontoma.

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Increased Expiratory Computed Tomography Density Reveals Possible Abnormalities in Radiologically Preserved Lung Parenchyma in Idiopathic Pulmonary Fibrosis.

Objectives: Idiopathic pulmonary fibrosis (IPF) is a progressive lethal chronic lung disease with unclear pathogenesis. Radiological hallmark is the pattern of usual interstitial pneumonia accentuated in peripheral and basal areas with otherwise preserved lung structure. One hypothesis is that alveolar collapse and consequent induration lead to fibrotic transformation of lung tissue. The aim of the study was to investigate normal-appearing tissue during expiration for signs of collapsibility and differences from other diseases or controls. Materials and Methods: We retrospectively assessed a total of 43 patients (15 IPFs, 13 chronic obstructive pulmonary diseases, and 15 controls) with nonenhanced computed tomography (CT) in inspiration and expiration, performed for routine clinical workup. Densitometry of visually unaffected lung tissue was conducted in all lung lobes with a region of interest of 15-mm in diameter on soft tissue kernel reconstruction (slice thickness, 1 mm) during inspiration and expiration. Results: One-factor analysis of variance analysis yielded significant difference in attenuation changes between inspiration and expiration of unaffected lung parenchyma among all subject groups in all lung lobes. For IPF patients, the highest differences in densities were observed in the lower lobes, which is the predominantly affected site of usual interstitial pneumonia. In the chronic obstructive pulmonary disease group, the density remained rather equal in the entire lung. Conclusions: High CT attenuation changes between inspiration and expiration in IPF patients might suggest altered lung parenchyma in normal-appearing tissue on CT. Density changes during the respiratory cycle might be explained by alveolar collapse of radiologically unaffected lung tissue possibly preceding fibrosis. These results support the concept of alveolar collapse preceding lung fibrosis in IPF. Copyright (C) 2017 Wolters Kluwer Health, Inc. All rights reserved.

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Increased Expiratory Computed Tomography Density Reveals Possible Abnormalities in Radiologically Preserved Lung Parenchyma in Idiopathic Pulmonary Fibrosis.

Objectives: Idiopathic pulmonary fibrosis (IPF) is a progressive lethal chronic lung disease with unclear pathogenesis. Radiological hallmark is the pattern of usual interstitial pneumonia accentuated in peripheral and basal areas with otherwise preserved lung structure. One hypothesis is that alveolar collapse and consequent induration lead to fibrotic transformation of lung tissue. The aim of the study was to investigate normal-appearing tissue during expiration for signs of collapsibility and differences from other diseases or controls. Materials and Methods: We retrospectively assessed a total of 43 patients (15 IPFs, 13 chronic obstructive pulmonary diseases, and 15 controls) with nonenhanced computed tomography (CT) in inspiration and expiration, performed for routine clinical workup. Densitometry of visually unaffected lung tissue was conducted in all lung lobes with a region of interest of 15-mm in diameter on soft tissue kernel reconstruction (slice thickness, 1 mm) during inspiration and expiration. Results: One-factor analysis of variance analysis yielded significant difference in attenuation changes between inspiration and expiration of unaffected lung parenchyma among all subject groups in all lung lobes. For IPF patients, the highest differences in densities were observed in the lower lobes, which is the predominantly affected site of usual interstitial pneumonia. In the chronic obstructive pulmonary disease group, the density remained rather equal in the entire lung. Conclusions: High CT attenuation changes between inspiration and expiration in IPF patients might suggest altered lung parenchyma in normal-appearing tissue on CT. Density changes during the respiratory cycle might be explained by alveolar collapse of radiologically unaffected lung tissue possibly preceding fibrosis. These results support the concept of alveolar collapse preceding lung fibrosis in IPF. Copyright (C) 2017 Wolters Kluwer Health, Inc. All rights reserved.

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MR Imaging Biomarkers in Amyotrophic Lateral Sclerosis

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Publication date: Available online 16 August 2017
Source:Academic Radiology
Author(s): Elias R. Melhem




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Differences in Texture Analysis Parameters Between Active Alveolitis and Lung Fibrosis in Chest CT of Patients with Systemic Sclerosis

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Publication date: Available online 12 August 2017
Source:Academic Radiology
Author(s): Christopher Kloth, Anya C. Blum, Wolfgang M. Thaiss, Heike Preibsch, Hendrik Ditt, Rainer Grimmer, Jan Fritz, Konstantin Nikolaou, Hans Bösmüller, Marius Horger
Rationale and ObjectivesThis study aimed to determine the diagnostic aid of computed tomography (CT) features for the differentiation of active alveolitis and fibrosis using a CT texture analysis (CTTA) prototype and CT densitometry in patients with systemic sclerosis (SSc) using ancillary high-resolution computed tomography (HRCT) features and their longitudinal course as standard of reference.Materials and MethodsWe retrospectively analyzed thin-slice noncontrast chest CT image data of 43 patients with SSc (18 men, mean age 51.55 ± 15.52 years; range 23–71 years). All of them had repeated noncontrast enhanced HRCT of the lung. Classification into active alveolitis or fibrosis was done on HRCT based on classical HRCT findings (active alveolitis [19; 44.2%] and fibrosis [24; 55.8%]) and their course at midterm. Results were compared to pulmonary functional tests and were followed up by CT. Ground glass opacity was considered suggestive of alveolitis, whereas coarse reticulation with parenchymal distortion, traction bronchiectasis, and honeycombing were assigned to fibrosis.ResultsStatistically significant differences in CTTA were found for first-order textural features (mean intensity, average, deviation, skewness) and second-order statistics (entropy of co-occurrence matrix, mean number of nonuniformity (NGLDM), entropy of NGLDM, entropy of heterogeneity, intensity, and average). Cut-off value for the prediction of fibrosis at baseline was significant for entropy of intensity (P value < .001) and for mean deviation (P value < .001), and for prediction of alveolitis was significant for uniformity of intensity (P value < .001) and for NGLDM (P value < .001).At pulmonary functional tests, forced expiratory volume in 1 second and single-breath diffusion capacity for carbon monoxide were significantly lower in fibrosis than in alveolitis 2.03 ± 0.78 vs. 2.61 ± 0.83, P < .016 and 4.51 ± 1.61 vs. 6.04 ± 1.75, P < .009, respectively. Differences in CT densitometry between alveolitis and fibrosis were not significant.ConclusionsCTTA parameters are significantly different in active alveolitis vs. fibrosis in patients with SSc and may be helpful for differentiation of these two entities.



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Introduction of a synthetic Thermococcus-derived α-amlyase gene into barley genome for increased enzyme thermostability in grains

Publication date: Available online 15 August 2017
Source:Electronic Journal of Biotechnology
Author(s): Daniel Mihálik, Marcela Gubišová, Ján Kraic, Martina Hudcovicová, Michaela Havrlentová, Jana Moravčíková, Miroslav Glasa, Ildikó Matušíková
BackgroundThe enzymes utilized in the process of beer production are generally sensitive to higher temperatures. About 60% of them are deactivated in drying the malt that limits the utilization of starting material in the fermentation process. Gene transfer from thermophilic bacteria is a promising tool for producing barley grains harboring thermotolerant enzymes.ResultsGene for α-amylase from hydrothermal Thermococcus, optimally active at 75–85°C and pH between 5.0 and 5.5, was adapted in silico to barley codon usage. The corresponding sequence was put under control of the endosperm-specific promoter 1Dx5 and after synthesis and cloning transferred into barley by biolistics. In addition to model cultivar Golden Promise we transformed three Slovak barley cultivars Pribina, Levan and Nitran, and transgenic plants were obtained. Expression of the ~50kDa active recombinant enzyme in grains of cvs. Pribina and Nitran resulted in retaining up to 9.39% of enzyme activity upon heating to 75°C, which is more than 4 times higher compared to non-transgenic controls. In the model cv. Golden Promise the grain α-amylase activity upon heating was above 9% either, however, the effects of the introduced enzyme were less pronounced (only 1.22 fold difference compared with non-transgenic barley).ConclusionsExpression of the synthetic gene in barley enhanced the residual α-amylase activity in grains at high temperatures.



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Fast three-dimensional whole-body post-mortem magnetic resonance angiography

Publication date: Available online 15 August 2017
Source:Journal of Forensic Radiology and Imaging
Author(s): Patrick J Laberke, Garyfalia Ampanozi, Thomas D Ruder, Dominic Gascho, Michael J Thali, Juergen Fornaro
PurposeThe goal of this study was to perform whole-body post-mortem magnetic resonance (PMMR) angiography with imaging quality comparable to that of post-mortem computed tomography (PMCT) angiography.MethodsAfter contrast medium injection into the arterial and venous vascular system of seven human corpses PMMR was performed using a fast three-dimensional T1 weighted spoiled gradient-echo sequence, followed by PMCT imaging. The contrast medium volumes inside the descending aorta and inside the inferior vena cava were measured both on PMMR and on PMCT images by means of image segmentation. Visualization quality of arterial and venous vessels as a function of contrast filling was scored according to a four-point scale and compared using the paired Wilcoxon signed rank test.ResultsThe contrast medium volume in the descending aorta decreased 12% on average from PMMR to PMCT angiography, while the contrast medium volume in the inferior vena cava increased by 11% on average. A total of 410 vessels were analyzed. Scores for all vessels were statistically significantly smaller for the PMMR angiography when compared to PMCT angiography (p=0.01). No statistically significant differences were found for the subgroups of large vessels (p=0.21), for the head and neck (p=0.16) or the abdomen (p=0.83) as well as for the thorax when the coronary arteries were left out (p=0.23).ConclusionsThis study demonstrates that immediate image acquisition after contrast injection and rapid 3D whole-body image acquisition offers good image quality in PMMR angiography with a vascular contrast comparable to PMCT angiography.



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Maternal hypothyroidism: An overview of current experimental models.

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Maternal hypothyroidism: An overview of current experimental models.

Life Sci. 2017 Aug 11;:

Authors: Ghanbari M, Ghasemi A

Abstract
Maternal hypothyroidism (MH) is the most common cause of transient congenital hypothyroidism. Different animal models are used for assessing developmental effects of MH in offspring. The severity and status of hypothyroidism in animal models must be a reflection of the actual conditions in humans. To obtain comparable results with different clinical conditions, which lead to MH in humans, several factors have been suggested for researchers to consider before designing the experimental models. Regarding development of fetal body systems during pregnancy, interference at different times provides different results and the appropriate time for induction of hypothyroidism should be selected based on accurate time of development of the system under assessment. Other factors that should be taken into consideration include, physiological and biochemical differences between humans and other species, thyroid hormone-independent effects of anti-thyroid drugs, circadian rhythms in TSH secretion, sex differences, physical and psychological stress. This review addresses essential guidelines for selecting and managing the optimal animal model for MH as well as discussing the pros and cons of currently used models.

PMID: 28807719 [PubMed - as supplied by publisher]



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Encapsulated follicular variant of papillary thyroid cancer: are these tumors really benign?

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Encapsulated follicular variant of papillary thyroid cancer: are these tumors really benign?

J Surg Res. 2017 Aug;216:138-142

Authors: Aburjania Z, Jang S, Montemayor-Garcia C, Lloyd RV, Schneider DF, Sippel RS, Chen H, Elfenbein DM

Abstract
BACKGROUND: Recent studies suggest that the encapsulated form of follicular variant of papillary thyroid cancer (eFVPTC) behaves more similarly to benign lesions and can be treated with thyroid lobectomy alone instead of total thyroidectomy. To distinguish aggressive cancers from more benign lesions more clearly, the objective of this study was to determine if the eFVPTC behaves less aggressively than the nonencapsulated variant (neFVPTC).
METHODS: A prospectively collected endocrine surgery database in our institution was reviewed for all patients with FVPTC on surgical pathology from 1999 to 2012. Samples were rereviewed to determine if the tumor was eFVPTC or neFVPTC, which were correlated with patient outcomes.
RESULTS: Of the 68 patients, 59 (87%) had eFVPTC and 9 (13%) had neFVPTC. The mean age was 48 y and 63% were female. Fifty-four of 64 patients (84%) who had a total thyroidectomy received radioactive iodine. The eFVPTC group had lower rates of cervical LN involvement (5% versus 22%, P = 0.2504). The median follow-up time was 3 y (0-13 y) and only two patients had recurrence, one with eFVPTC and one with neFVPTC. None of the patients had distant metastasis or died of their disease.
CONCLUSIONS: eFVPTCs appear to have a lower rate of cervical lymph node metastases compared with neFVPTCs, but recurrent disease may be seen in both subtypes. These findings suggest eFVPTC can be managed more conservatively.

PMID: 28807198 [PubMed - in process]



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Long-term outcomes of lateral neck dissection in patients with recurrent or persistent well-differentiated thyroid cancer.

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Long-term outcomes of lateral neck dissection in patients with recurrent or persistent well-differentiated thyroid cancer.

Thyroid. 2017 Aug 15;:

Authors: Chinn SB, Zafereo M, Waguespack SG, Edeiken BS, Roberts DB, Clayman G

Abstract
BACKGROUND: Well-differentiated thyroid carcinoma (WDTC) has a high predilection for regional metastatic spread; rates for WDTC lateral neck recurrence are reported to be as high as 24% in patients after initial thyroidectomy, lateral neck surgery and adjuvant radioactive iodine treatment (RAI). The objective of the study was to evaluate the efficacy, safety, and long-term outcome of comprehensive lateral neck dissection (LND) of levels II-V for recurrent or persistent WDTC in a tertiary referral center.
METHODS: We retrospectively analyzed our standardized approach of LND for recurrent WDTC in the lateral neck compartment. Survival was analyzed by Cox-regression analysis.
RESULTS: Three-hundred and seven patients underwent 429 LND for cytopathology confirmed lateral neck recurrent WDTC at the University of Texas MD Anderson Cancer Center between 1994 and 2012. The vast majority (90%) of patients were treated originally elsewhere. Multi-level lateral neck dissection had been originally performed in 80% of patients, with 17% having undergone at least 2 previous operations. Two-hundred sixty-seven patients (87%) had previous RAI. The most common levels of recurrence were levels III and IV (33% and 33%, respectively). Post-operative complications were seen in 7% of patients. Median follow-up was 7.2 years. In-field lateral neck control was 96% at 10 years. Overall lateral neck regional control, overall survival (OS) and disease-specific survival (DSS) at 10 years was 88%, 78% and 91% respectively. When stratifying by age (<24 years, 24-50 years and >50 years), OS and DSS was significantly better in patients <50 years (OS: p<0.001 and DSS: p<0.001), however there was worse overall lateral neck control in the younger group (<24 years) (p=0.04). Regional recurrence after salvage LND occurred within a median time interval of 20.0 months (2.9-121.3 months), of which 2% (8/429) developed in-field lateral neck recurrences. Of those with any lateral neck recurrence after salvage LND, 24 out of 30 patients (80%) successfully underwent another LND, resulting in an ultimate 98% lateral neck regional control rate.
CONCLUSIONS: Expert comprehensive LND of levels II-V is associated with few perioperative complications and results in very high in-field regional control rate and ultimate lateral neck control in recurrent/persistent WDTC.

PMID: 28806882 [PubMed - as supplied by publisher]



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Antitumor activity of the dual PI3K/MTOR inhibitor, PF-04691502, in combination with radiation in head and neck cancer

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Publication date: Available online 16 August 2017
Source:Radiotherapy and Oncology
Author(s): Nathan Tonlaar, Sandra Galoforo, Bryan J. Thibodeau, Samreen Ahmed, Thomas G. Wilson, Paola Yumpo Cardenas, Brian Marples, George D. Wilson
Background and purposeHead and neck squamous cell carcinoma (HNSCC) remains a clinical challenge where new treatments are required to supplement the current-standard-of care of concurrent chemoradiation. The PI3K/AKT/MTOR pathway has been identified from several next generation DNA sequencing studies to be commonly altered and activated in HNSCC.Material and methodsIn this study we investigated the activity of PF-04691502, an orally active ATP-competitive, dual inhibitor of PI3K and mTOR, in combination with a clinically relevant fractionated radiation treatment in two contrasting, well characterized, low passage HNSCC models.ResultsWe found that PF-04691502 combined synergistically with radiation in the UT-SCC-14 model derived from a primary cancer but was ineffective in the UT-SCC-15 model which was derived from a nodal recurrence. Further examination of the status of key signaling pathways combined with next generation DNA sequencing of a panel of 160 cancer-associated genes revealed crucial differences between the two models that could account for the differential effect. The UT-SCC-15 cell line was characterized by a higher mutational burden, an excess of variants in the PI3K/AKT/MTOR pathway, increased constitutive activity of PI3K, AKT1 and 2 and MTOR and an inability to inhibit key phosphorylation events in response to the treatments.ConclusionThis study clearly highlights the promise of agents such as PF-04691502 in selected HNSCCs but also emphasizes the need for molecular characterization and alternative treatment strategies in non-responsive HNSCCs.



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Development of a virtual spacer to support the decision for the placement of an implantable rectum spacer for prostate cancer radiotherapy: Comparison of dose, toxicity and cost-effectiveness

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Publication date: Available online 16 August 2017
Source:Radiotherapy and Oncology
Author(s): Yvonka van Wijk, Ben G.L. Vanneste, Sean Walsh, Skadi van der Meer, Bram Ramaekers, Wouter van Elmpt, Michael Pinkawa, Philippe Lambin
IntroductionPrevious studies have shown that the implantable rectum spacer (IRS) is not beneficial for all patients. A virtual IRS (V-IRS) was constructed to help identify the patients for whom it is cost-effective to implant an IRS, and its viability as a tool to tailor the decision of an IRS implantation to be beneficial for the specified patient was assessed. Please watch animation:(https://www.youtube.com/watch?v=tDlagSXMKqw)Materials and methodsThe V-IRS was tested on 16 patients: 8 with a rectal balloon implant (RBI) and 8 with a hydrogel spacer. A V-IRS was developed using 7 computed tomography (CT) scans of patients with a RBI. To examine the V-IRS, CT scans before and after the implantation of an IRS were used. IMRT plans were made based on CT scans before the IRS, after IRS and with the V-IRS, prescribing 70 Gray (Gy) to the planning target volume. Toxicity was accessed using externally validated normal tissue complication probability (NTCP) models, and the Cost-effectiveness was analyzed using a published Markov model.ResultsThe rectum volume receiving 75Gy (V75) were improved by both the IRS and the V-IRS with on average 4.2% and 4.3% respectively. The largest NTCP reduction resulting from the IRS and the V-IRS was 4.0% and 3.9% respectively. The RBI was cost-effective for 1 out of 8 patients, and the hydrogel was effective for 2 out of 8 patients, and close to effective for a third patient. The classification accuracy of the model, regarding cost-effectiveness, was 100%.ConclusionThe V-IRS approach in combination with a toxicity prediction model and a cost-effectiveness analyses is a promising basis for a decision support tool for the implantation of either a hydrogel spacer or a rectum balloon implant.



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Sparing all salivary glands with IMRT for head and neck cancer: Longitudinal study of patient-reported xerostomia and head-and-neck quality of life

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Publication date: Available online 16 August 2017
Source:Radiotherapy and Oncology
Author(s): Peter G. Hawkins, Jae Y. Lee, Yanping Mao, Pin Li, Michael Green, Francis P. Worden, Paul L. Swiecicki, Michelle L. Mierzwa, Matthew E. Spector, Matthew J. Schipper, Avraham Eisbruch
Background and purposeWhile parotid-sparing intensity modulated radiotherapy (IMRT) has demonstrated superiority to conventional RT in terms of observer-rated xerostomia, patient-reported outcome measures (PROMs) have only marginally improved. We investigated how sparing all salivary glands affects PROMs.Materials and methodsPatients treated to the bilateral neck with all-gland-sparing IMRT answered xerostomia (XQ) and head-and-neck quality of life (HNQOL) questionnaires. Longitudinal regression was used to assess the relationship between questionnaire scores and mean bilateral parotid gland (bPG), contralateral submandibular gland (cSMG), and oral cavity (OC) doses. Marginal R2 and Akaike information criterion (AIC) were used for model evaluation.Results252 patients completed approximately 600 questionnaires. On univariate analysis, bPG, cSMG, and OC doses significantly correlated with XQ-summary, XQ-eating, and HNQOL-eating scores. On multivariate analysis, bPG and OC doses significantly correlated with XQ-summary, XQ-eating, and HNQOL-eating scores; and cSMG dose with HNQOL-summary. Combining doses to all three structures yielded the highest R2 for XQ-summary, XQ-rest, XQ-eating, and HNQOL-eating. In the 147 patients who received a mean cSMG dose ≤39Gy, there were no failures in contralateral level IB.ConclusionsReducing doses to all salivary glands maximizes PROMs. A cSMG dose constraint of ≤39Gy does not increase failure risk.



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Treatment of the ventral intermediate nucleus for medically refractory tremor: A cost-analysis of stereotactic radiosurgery versus deep brain stimulation

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Publication date: Available online 14 August 2017
Source:Radiotherapy and Oncology
Author(s): Shearwood McClelland, Jerry J. Jaboin
IntroductionMedically refractory tremor treatment has evolved over the past half-century from intraoperative thalamotomy to deep brain stimulation (DBS) of the thalamic ventral intermediate nucleus (VIM). Within the past 15years, unilateral radiosurgical VIM thalamotomy has emerged as a comparably efficacious treatment modality.MethodsAn extensive literature search of VIM DBS series was performed; the total cost of VIM DBS was calculated from hospitals geographically representative of the entire United States using current procedural terminology and work relative value unit (RVU) codes. The 2016 Medicare Ambulatory Payment Classification for stereotactic radiosurgery (SRS) was added to the work RVU to determine the total cost of VIM SRS for both Gamma Knife and linear accelerator SRS. Cost estimates assumed that VIM DBS was performed without intraoperative microelectrode recording.ResultThe mean unilateral VIM DBS cost was $17,932.41 per patient. For SRS VIM, the total costs for Gamma Knife ($10,811.77) and linear accelerator ($10,726.40) were 40% less expensive than for unilateral VIM DBS.ConclusionRadiosurgery of the VIM is 40% less expensive than unilateral VIM DBS in treatment of medically refractory tremor, regardless of radiosurgical modality. This finding argues for increased radiation oncology involvement in the management of medically refractory tremor patients.



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Patient safety is improved with an incident learning system—Clinical evidence in brachytherapy

Publication date: Available online 17 August 2017
Source:Radiotherapy and Oncology
Author(s): Christopher L. Deufel, Luke B. McLemore, Luis E. Fong de los Santos, Kelly L. Classic, Sean S. Park, Keith M. Furutani
Background and purposeHealth leaders have advocated for incident learning systems (ILSs) to prevent errors, but there is limited evidence demonstrating that ILSs improve cancer patient safety. Herein, we report a long-term retrospective review of ILS reports for the brachytherapy practice at a large academic institution.Material and methodsOver a nine-year period, the brachytherapy practice was encouraged to report all standard operating procedure deviations, including low risk deviations. A multidisciplinary committee assigned root causes and risk scores to all incidents. Evidence based practice changes were made using ILS data, and relevant incidents were communicated to all staff in order to reduce recurrence rates.Results5258 brachytherapy procedures were performed and 2238 incidents were reported from 2007 to 2015. A ramp-up period was observed in ILS participation between 2007 (0.12 submissions/procedures) and 2011 (1.55 submissions/procedures). Participation remained stable between 2011 and 2015, and we achieved a 60% (p<0.001) decrease in the risk of dose error or violation of radiation safety policy and a 70% (p<0.001) decrease in frequency of high composite-risk scores. Significant decreases were also observed in incidents with root causes of poor communication (60% decrease, p<0.001) and poor quality of written procedures (59% decrease, p<0.001).ConclusionsImplementation of an ILS in brachytherapy significantly reduced risk during cancer patient care. Safety improvements have been sustained over several years.



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Radioecological assessment and radiometric dating of sediment cores from dynamic sedimentary systems of Pra and Volta estuaries (Ghana) along the Equatorial Atlantic

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Publication date: November 2017
Source:Journal of Environmental Radioactivity, Volumes 178–179
Author(s): E. Klubi, J.M. Abril, E. Nyarko, A. Laissaoui, M. Benmansour
The Volta and Pra estuaries (Ghana, West Africa) are dynamical sedimentary systems whose natural equilibrium is being affected by anthropogenic activities. This paper reports depth-distributions of 210Pb, 226Ra, 234Th, 40K, 228Ra and 137Cs for two sediment cores from these estuaries. Bulk densities were not steady-state and well correlated with 40K (p < 0.00005). Unsupported 210Pb profiles were incomplete, non-monotonic and showed large fluctuations. The assumptions involved in the common 210Pb-based dating models were not meet in these dynamical scenarios, and the use of 137Cs as a time-marker is difficult in Equatorial and South-Hemisphere countries due to its low fallout rates. Chronologies have been solved with the new 210Pb-based TERESA model, which operates with varying but statistically correlated fluxes and sediment accumulation rates (SAR). The core from the Volta reflects the conditions prevailing after the construction of the Akosombo Dam, with a mean SAR of 1.05 ± 0.03 g cm−2·y−1, while a higher value of 2.73 ± 0.06 g cm−2·y−1 was found in the Pra, affected by intense gold mining activities along its course. Radiological and radioecological assessments have been conducted by applying the UNSCEAR protocols and the ERICA model, respectively. The measured radionuclide concentrations do not pose any significant risk for the environment and human health.



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Improved performance comparisons of radioxenon systems for low level releases in nuclear explosion monitoring

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Publication date: November 2017
Source:Journal of Environmental Radioactivity, Volumes 178–179
Author(s): Derek A. Haas, Paul W. Eslinger, Theodore W. Bowyer, Ian M. Cameron, James C. Hayes, Justin D. Lowrey, Harry S. Miley
The Comprehensive Nuclear-Test-Ban Treaty bans all nuclear tests and mandates development of verification measures to detect treaty violations. One verification measure is detection of radioactive xenon isotopes produced in the fission of actinides. The International Monitoring System (IMS) currently deploys automated radioxenon systems that can detect four radioxenon isotopes. Radioxenon systems with lower detection limits are currently in development. Historically, the sensitivity of radioxenon systems was measured by the minimum detectable concentration for each isotope. In this paper we analyze the response of radioxenon systems using rigorous metrics in conjunction with hypothetical representative releases indicative of an underground nuclear explosion instead of using only minimum detectable concentrations. Our analyses incorporate the impact of potential spectral interferences on detection limits and the importance of measuring isotopic ratios of the relevant radioxenon isotopes in order to improve discrimination from background sources particularly for low-level releases. To provide a sufficient data set for analysis, hypothetical representative releases are simulated every day from the same location for an entire year. The performance of three types of samplers are evaluated assuming they are located at 15 IMS radionuclide stations in the region of the release point. The performance of two IMS-deployed samplers and a next-generation system is compared with proposed metrics for detection and discrimination using representative releases from the nuclear test site used by the Democratic People's Republic of Korea.



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Applications of radon and radium isotopes to determine submarine groundwater discharge and flushing times in Todos os Santos Bay, Brazil

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Publication date: November 2017
Source:Journal of Environmental Radioactivity, Volumes 178–179
Author(s): Vanessa Hatje, Karina Kammer Attisano, Marcelo Friederichs Landim de Souza, Barbara Mazzilli, Joselene de Oliveira, Tamires de Araújo Mora, William C. Burnett
Todos os Santos Bay (BTS) is the 2nd largest bay in Brazil and an important resource for the people of the State of Bahia. We made measurements of radon and radium in selected areas of the bay to evaluate if these tracers could provide estimates of submarine groundwater discharge (SGD) and flushing times of the Paraguaçu Estuary and BTS. We found that there were a few areas along the eastern and northeastern shorelines that displayed relatively high radon and low salinities, indicating possible sites of enhanced SGD. A time-series mooring over a tidal cycle at Marina do Bonfim showed a systematic enrichment of the short-lived radium isotopes 223Ra and 224Ra during the falling tide. Assuming that the elevated radium isotopes were related to SGD and using measured radium activities from a shallow well at the site, we estimated groundwater seepage at about 70 m3/day per unit width of shoreline. Extrapolating to an estimated total shoreline length provided a first approximation of total (fresh + saline) SGD into BTS of 300 m3/s, about 3 times the average river discharge into the bay. Just applying the shoreline lengths from areas identified with high radon and reduced salinity results in a lower SGD estimate of 20 m3/s. Flushing times of the Paraguaçu Estuary were estimated at about 3–4 days based on changing radium isotope ratios from low to high salinities. The flushing time for the entire BTS was also attempted using the same approach and resulted in a surprisingly low value of only 6–8 days. Although physical oceanographic models have proposed flushing times on the order of months, a simple tidal prism calculation provided results in the range of 4–7 days, consistent with the radium approach. Based on these initial results, we recommend a strategy for refining both SGD and flushing time estimates.



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Temporary Hearing Threshold Shift in Healthy Volunteers with Hearing Protection Caused by Acoustic Noise Exposure during 3-T Multisequence MR Neuroimaging.

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Temporary Hearing Threshold Shift in Healthy Volunteers with Hearing Protection Caused by Acoustic Noise Exposure during 3-T Multisequence MR Neuroimaging.

Radiology. 2017 Aug 16;:161622

Authors: Jin C, Li H, Li X, Wang M, Liu C, Guo J, Yang J

Abstract
Purpose To determine whether a single 51-minute exposure to acoustic noise during 3-T multisequence magnetic resonance (MR) neuroimaging could affect the hearing threshold of healthy adults with earplugs and sponge mats as hearing protection. Materials and Methods With earplugs and motion-refraining sponge mats as hearing protection, 26 healthy young adults underwent 3-T MR neuroimaging imaging that included T1-weighted three-dimensional gradient-echo sequence, T2-weighted fast spin-echo sequence, diffusion-tensor imaging, diffusion-kurtosis imaging, T2*-weighted three-dimensional multiecho gradient-echo sequence, and blood oxygen level-dependent imaging. Automated auditory brainstem response (ABR) was used to measure the hearing thresholds within 24 hours before, within 20 minutes after, and 25 days after the MR examination. One-way repeated-measure analysis of variance with Bonferroni adjustment was used to compare automated ABR results among the three tests and partial η(2) (ηp(2)) was reported as a measure of effect size. Results Automated ABR results showed significantly increased mean threshold shift of 5.0 dB ± 8.1 (standard deviation) (left ear: 4.8 dB ± 9.2 [95% confidence interval: 1.09, 8.53], ηp(2) = 0.221, P = .013; right ear: 5.2 dB ± 6.9 [95% confidence interval: 2.36, 8.02], ηp(2) = 0.364, P = .001) immediately after the MR examination compared with the baseline study. This shift is below the temporary threshold shift of 40-50 dB that is associated with cochlea nerve changes. Automated ABR obtained at day 25 after MR imaging showed no significant differences from baseline (left ear: -2.3 dB ± 8.6 [95% confidence interval: -5.79, 1.78], ηp(2) = 0.069, P = .185; right ear: 0.4 dB ± 7.3 [95% confidence interval: -3.35, 2.58], ηp(2) = 0.003, P = .791). Conclusion A 3-T MR neuroimaging examination with the acoustic noise at equivalent sound pressure level of 103.5-111.3 dBA lasting 51 minutes can cause temporary hearing threshold shift in healthy volunteers with hearing protection. (©) RSNA, 2017.

PMID: 28813235 [PubMed - as supplied by publisher]



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Cardiac MR Strain: A Noninvasive Biomarker of Fibrofatty Remodeling of the Left Atrial Myocardium.

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Cardiac MR Strain: A Noninvasive Biomarker of Fibrofatty Remodeling of the Left Atrial Myocardium.

Radiology. 2017 Aug 16;:162787

Authors: Huber AT, Lamy J, Rahhal A, Evin M, Atassi F, Defrance C, Lebreton G, Clément K, Berthet M, Isnard R, Leprince P, Cluzel P, Hatem SN, Kachenoura N, Redheuil A

Abstract
Purpose To determine whether left atrial (LA) strain quantification with cardiac magnetic resonance (MR) imaging feature tracking is associated with the severity of LA fibrofatty myocardial remodeling at histologic analysis. Materials and Methods This prospective case-control study was approved by the institutional review board. LA strain was evaluated with cardiac MR feature tracking between January 2014 and March 2015 in 13 consecutive patients (mean age, 61 years ± 19; nine male) with mitral regurgitation in the 24 hours before mitral valve surgery and 13 age- and sex-matched healthy control subjects. LA strain parameters were compared first between control subjects and patients and then according to atrial fibrillation and mitral regurgitation status. Associations between LA strain and histology of preoperative biopsies were reported by using receiver operating characteristic curve analysis and Spearman correlation. Results Peak longitudinal atrial strain (PLAS) was significantly lower in patients with mitral regurgitation than in healthy control subjects (P < .001). Increased LA remodeling was significantly related to altered LA strain, and the strongest association was found between PLAS and the degree of fibrofatty myocardial replacement at histologic analysis (r = -0.75, P = .017). LA end-diastolic volume was increased in patients with mitral regurgitation when compared with that in healthy volunteers (P < .001) because of volume overload; however, volume did not correlate with the histologic degree of LA fibrofatty replacement (r = -0.35, P = .330). Conclusion LA strain, especially PLAS, correlates strongly with the degree of fibrofatty replacement at histologic analysis. Such functional imaging biomarker in combination with LA volumetry could help to guide clinical decisions, since myocardial structural remodeling is a known morphologic substrate of LA dysfunction leading to atrial fibrillation with adverse outcome. (©) RSNA, 2017 Online supplemental material is available for this article.

PMID: 28813234 [PubMed - as supplied by publisher]



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Risk of Meningioma after CT of the Head.

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Risk of Meningioma after CT of the Head.

Radiology. 2017 Aug 14;:161433

Authors: Nordenskjöld AC, Bujila R, Aspelin P, Flodmark O, Kaijser M

Abstract
Purpose To investigate the association between exposure to head computed tomography (CT) and subsequent risk of meningioma. Materials and Methods The study was approved by the local ethics committee. A cohort of 26 370 subjects was retrospectively collected from a radiology archive of CT examinations of the head performed from 1973 through 1992. For comparison, an age- and sex-matched cohort of 96 940 subjects who were not exposed to CT (unexposed cohort) was gathered. The risk of meningioma was assessed by using data from the Swedish Cancer Registry; however, one-third of patients with meningioma had to be excluded because they either had a prevalent meningioma or other brain tumor at the first CT examination or had undergone radiation treatment to the head. Hazard ratios (HRs) were calculated from time of exposure to the occurrence of meningioma or death or until December 31, 2010, with logistic regression. Results Comparison of exposed and unexposed cohorts showed that there was no statistically significant increase in the risk of meningioma after exposure to CT of the head (HR: 1.49; 95% confidence interval: 0.97, 2.30; P = .07). If incident cases at the time of the first CT examination were not excluded, the risk of meningioma would have been falsely increased (HR: 2.28; 95% confidence interval: 1.56, 3.33; P = .0001). Conclusion When prevalent cases of meningioma at first exposure to CT of the head are excluded, no statistically significant increase in risk of meningioma was found among exposed subjects compared with unexposed control subjects. (©) RSNA, 2017.

PMID: 28809584 [PubMed - as supplied by publisher]



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Iodixanol versus Iopromide at Coronary CT Angiography: Lumen Opacification and Effect on Heart Rhythm-the Randomized IsoCOR Trial.

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Iodixanol versus Iopromide at Coronary CT Angiography: Lumen Opacification and Effect on Heart Rhythm-the Randomized IsoCOR Trial.

Radiology. 2017 Aug 15;:162779

Authors: Lubbers MM, Kock M, Niezen A, Galema T, Kofflard M, Bruning T, Kooij HS, van Valen H, Dijkshoorn M, Booij R, Padmos A, Vogels A, Budde RPJ, Nieman K

Abstract
Purpose To show that equal coronary lumen opacification can be achieved with iso- and low-osmolar contrast media when it is injected at the same iodine delivery rate with contemporary cardiac computed tomographic (CT) protocols and to investigate the cardiovascular effect of iso-osmolar contrast media and the image quality achieved. Materials and Methods Institutional review board approval and written informed consent were obtained for the Effect of Iso-osmolar Contrast Medium on Coronary Opacification and Heart Rhythm in Coronary CT Angiography, or IsoCOR, trial. Between November 2015 and August 2016, 306 patients (167 [55%] women) at least 18 years old (weight range, 50-125 kg), were prospectively randomized to receive iso-osmolar iodixanol 270 or low-osmolar iopromide 300 contrast media. All coronary segments were assessed for intraluminal opacification and image quality and were compared by using the Student t test. Heart rate, arrhythmia, patient discomfort, and adverse events also were monitored. Results Mean measured coronary attenuation values ± standard deviation were comparable between the iodixanol 270 and iopromide 300 contrast media groups (469 HU ± 167 vs 447 HU ± 166, respectively [P = .241]; 95% confidence interval: -15.1, 60.0), including those from subanalyses. Adjusted for the lower iodine concentration, the mean iodixanol 270 bolus was larger compared with that of iopromide 300 (76.8 mL ± 11.6 vs 69.7 mL ± 10.8, respectively; P < .001). The higher injection rate was associated with higher pressure (777 kPa ± 308 vs 630 kPa ± 252, respectively; P < .001). Although in the iodixanol 270 group patients experienced less heat discomfort (72% vs 86%, respectively; P < .001), no differences in heart rate or rhythm were observed. Conclusion If injected at comparable iodine delivery rates, the iso-osmolar contrast medium iodixanol 270 is not inferior to low-osmolar contrast medium iopromide 300 for assessment of coronary opacification. Iodixanol 270 was associated with less heat discomfort, but did not affect heart rate differently compared with iopromide 300. (©) RSNA, 2017 Online supplemental material is available for this article.

PMID: 28809582 [PubMed - as supplied by publisher]



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Quantitative approach to the posterior cranial fossa and craniocervical junction in asymptomatic children with achondroplasia

Abstract

Purpose

We propose an magnetic resonance imaging (MRI)-based quantitative morphovolumetric approach to the posterior cranial fossa (PCF) and craniocervical junction (CCJ) changes in achondroplastic patients investigating possible associations with ventriculomegaly and medullary compression.

Methods

We analyzed MRI of 13 achondroplastic children not treated by surgery. 3D FSPGR T1-weighted images were used to analyze (1) PCF synchondroses; (2) PCF volume (PCFV), PCF brain volume (PCFBV), PCFV/PCFBV ratio, cerebellar volume, cerebrospinal fluid (CSF) spaces volume, and IV ventricle volume; (3) PCF (clivus, supraocciput, exocciput lengths, tentorial angle) and CCJ (AP and LL diameters of foramen magnum (FM)) morphometry; (4) measurements of FM and jugular foramina (JF) areas; and (5) supratentorial ventricular volume.

Results

All patients showed synostosis of spheno-occipital synchondroses, eight showed synostosis of intra-occipital synchondroses, nine showed CCJ impingement on the cervical cord but only three had cervical myelopathy. Compared to controls, clivus and exocciput lengths, LL and AP diameters of FM, FM area and JF area were significantly reduced, supraocciput length, tentorial angle, PCFV, PCFBV, cerebellar volume, supratentorial ventricular system volume were significantly increased. A correlation was found between clivus length and supratentorial ventricular volume, premature closure of intra-occipital synchondroses and FM area while a trend was found between FM area and supraocciput length.

Conclusion

Our analysis demonstrates a relationship between the shortening of the clivus and the ventriculomegaly. On the other hand the premature closure of PCF synchondroses, the shape, and the growth direction of supraocciput bone contribute to reduce the FM area, causing in some patients medullary compression.



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Bildgebende Verfahren der modernen Schockraumdiagnostik

Zusammenfassung

Das moderne Schockraummanagement setzt die interdisziplinäre Zusammenarbeit sowie die horizontale Kommunikation eines Kernteams aus Anästhesisten, Chirurgen und Radiologen voraus. Da die Verweildauer im Schockraum die Behandlungsergebnisse und die Morbidität/Letalität eines Schwerverletzten beeinflusst, stellt die Zeitoptimierung eines der Hauptziele dar. Mithilfe der direkten Einbindung moderner bildgebender Verfahren sollen die Traumaschäden binnen kürzester Zeit erkannt werden, um ein prioritätenorientiertes Vorgehen bezüglich der Therapie zu ermöglichen. Die Radiologie nimmt Einfluss auf die Struktur- und Prozessqualität, das Management und die Weiterentwicklung der Schockraumalgorithmen im Hinblick auf den Einsatz bildgebender Verfahren. Im Einzelfall wird dies durch interventionelle Therapieverfahren ergänzt. Basierend auf der gegenwärtigen Datenlage und den Frankfurter Erfahrungen werden die aktuellen diagnostischen Konzepte in der Schockraumdiagnostik vorgestellt.



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Quantitative approach to the posterior cranial fossa and craniocervical junction in asymptomatic children with achondroplasia

Abstract

Purpose

We propose an magnetic resonance imaging (MRI)-based quantitative morphovolumetric approach to the posterior cranial fossa (PCF) and craniocervical junction (CCJ) changes in achondroplastic patients investigating possible associations with ventriculomegaly and medullary compression.

Methods

We analyzed MRI of 13 achondroplastic children not treated by surgery. 3D FSPGR T1-weighted images were used to analyze (1) PCF synchondroses; (2) PCF volume (PCFV), PCF brain volume (PCFBV), PCFV/PCFBV ratio, cerebellar volume, cerebrospinal fluid (CSF) spaces volume, and IV ventricle volume; (3) PCF (clivus, supraocciput, exocciput lengths, tentorial angle) and CCJ (AP and LL diameters of foramen magnum (FM)) morphometry; (4) measurements of FM and jugular foramina (JF) areas; and (5) supratentorial ventricular volume.

Results

All patients showed synostosis of spheno-occipital synchondroses, eight showed synostosis of intra-occipital synchondroses, nine showed CCJ impingement on the cervical cord but only three had cervical myelopathy. Compared to controls, clivus and exocciput lengths, LL and AP diameters of FM, FM area and JF area were significantly reduced, supraocciput length, tentorial angle, PCFV, PCFBV, cerebellar volume, supratentorial ventricular system volume were significantly increased. A correlation was found between clivus length and supratentorial ventricular volume, premature closure of intra-occipital synchondroses and FM area while a trend was found between FM area and supraocciput length.

Conclusion

Our analysis demonstrates a relationship between the shortening of the clivus and the ventriculomegaly. On the other hand the premature closure of PCF synchondroses, the shape, and the growth direction of supraocciput bone contribute to reduce the FM area, causing in some patients medullary compression.



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New techniques in interventional neuroradiology: Should we really randomize the first patient?

Publication date: Available online 12 August 2017
Source:Journal of Neuroradiology
Author(s): L. Pierot, L. Kanagaratnam, M. Gawlitza, S. Soize, M. Dramé




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