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991.
Imaging plays a major role in the identification, grading, and treatment of cerebral arteriovenous malformations and cerebral dural arteriovenous fistulas. Digital subtraction angiography is the gold standard in the diagnosis and characterization of these vascular malformations, but advances in both magnetic resonance imaging and computed tomography, including advanced imaging techniques, have provided new tools for further characterizing these lesions as well as the surrounding brain structures that may be affected. This article discusses the role of conventional as well as advanced imaging modalities that are providing novel ways to characterize these vascular malformations.  相似文献   
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Posterior cruciate ligament (PCL) injuries from tibial avulsions are rare in the paediatric setting. One would need a high index of suspicion as clinical examination may be difficult, especially in the early period. Magnetic resonance imaging is an excellent diagnostic modality for this condition and other associated injuries within the knee. We report a rare case in which the patient had a PCL avulsion off the tibial insertion site with an associated posterior horn medial meniscal tear off the posterior capsule. He was treated through open reduction and internal fixation of the avulsed fragment with suture repair of the meniscal tear. We emphasize the importance of diagnosing and managing associated intra-articular injuries when dealing with the rare condition of PCL tibial avulsion in the paediatric setting.  相似文献   
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Objective:To explore the utility of first-order MRI-texture analysis (TA) parameters in predicting histologic grade and muscle invasion in urinary bladder cancer (UBC).Methods:After ethical clearance, 40 patients with UBC, who were imaged on a 3.0-Tesla scanner, were retrospectively included. Using the TexRADTM platform, two readers placed freehand ROI on the sections demonstrating the largest dimension of the tumor, evaluating only one tumor per patient. Interobserver reproducibility was assessed using the intraclass correlation coefficient (ICC). Mann–Whitney U test and ROC curve analysis were used to identify statistical significance and select parameters with high class separation capacity (AUC >0.8), respectively. Pearson’s test was used to identify redundancy in the results.Results:All texture parameters showed excellent ICC. The best parameters in differentiating high and low-grade tumors were mean/ mean of positive pixels (MPP) at SSF 0 (AUC: 0.897) and kurtosis at SSF 5 (AUC: 0.828) on the ADC images. In differentiating muscle invasive from non-muscle invasive tumors, mean/ MPP at SSF 0 on the ADC images showed AUC >0.8; however, this finding resulted from the confounding effect of high-grade histology on the ADC values of muscle invasive tumors.Conclusion:MRI-TA generated few parameters which were reproducible and useful in predicting histologic grade. No independent parameters predicted muscle invasion.Advances in knowledge:There is lacuna in the literature concerning the role of MRI-TA in the prediction of histologic grade and muscle invasion in UBC. Our study generated a few first-order parameters which were useful in predicting high-grade histology.  相似文献   
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Research in schizophrenia has tended to emphasize deficits in higher cognitive abilities, such as attention, memory, and executive function. Here we provide evidence for dysfunction at a more fundamental level of perceptual processing, temporal integration. On a measure of flicker fusion, patients with schizophrenia exhibited significantly lower thresholds than age and education matched healthy controls. We reasoned that this finding could result from a longer window of temporal integration or could reflect diminished repetition suppression: if every frame of the repeating stimulus were represented as novel, its perceived duration would be accordingly longer. To tease apart these non-exclusive hypotheses, we asked patients to report the number of stimuli perceived on the screen at once (numerosity) as they watched rapidly flashing stimuli that were either repeated or novel. Patients reported significantly higher numerosity than controls in all conditions, again indicating a longer window of temporal integration in schizophrenia. Further, patients showed the largest difference from controls in the repeated condition, suggesting a possible effect of weaker repetition suppression. Finally, we establish that our findings generalize to several different classes of stimuli (letters, pictures, faces, words, and pseudo-words), demonstrating a non-specific effect of a lengthened window of integration. We conclude that the visual system in schizophrenics integrates input over longer periods of time, and that repetition suppression may also be deficient. We suggest that these abnormalities in the processing of temporal information may underlie higher-level deficits in schizophrenia and account for the disturbed sense of continuity and fragmentation of events in time reported by patients.  相似文献   
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Aim:

Head and neck cancers (HNCa) are the most common cancers among males in India and 70-80% present in advanced stage. The study aims to assess symptom burden and quality of life (QOL) in advanced incurable HNCa patients at presentation.

Materials and Methods:

One hundred patients were asked to fill EORTC QLQ-C15-PAL questionnaire, which consisted of Global QOL, physical functioning (PF), emotional functioning (EF), fatigue (FA), nausea-vomiting (NV), pain (PA), dyspnea (DY), sleep (SL), appetite (AP), and constipation (CO). Additional questions pertaining to swallowing (SW), hoarseness (HO), cough (CG), weight loss (WL), using pain killers (PK), taste (TA), bleeding (BL), hearing (HE), pain in neck lump (PALMP), opening mouth (OM), and oral secretions (OS) were asked based on a modified EORTC-HN35 questionnaire. Scoring was according to EORTC scoring manual. Mean, median and range were calculated for each item for the entire cohort.

Results:

The female:male ratio was 17:83.42% of them were ≥60 years of age. Sixty-six patients had T4, 25 had T3, 36 had N2, and 33 had N3 disease. Median QOL was 50 (range 0-83.33) and PF was 77.78 (0-100). Median score for EF and FA was 50. Median score for PA, PK, and SL was 66.67 while that for AP was 33.33. Median value for SW, HO, WL, BL, PALMP, OM, and OS was 33.33 (100-0) while TA, CG, NV, DY, and HE had a median score of 0.00.

Conclusion:

Advanced HNCa has a significant burden of symptoms. These results would help in giving patients better symptom directed therapies and improve their QOL.  相似文献   
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