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41.
Parapharyngeal tumours are frequently encountered in clinical practice and are often difficult to diagnose upon clinical examination due to the anatomic complexity of the region. We report a rare case of extracranial meningioma of the parapharyngeal space in a patient with no history of von Recklinghausen's disease, family history of meningioma or central neurofibromatosis (NF-2). The purpose of this report is to reiterate and emphasize the role of CT and MRI in the diagnosis of parapharyngeal masses, and to describe the characteristic radiological features of extracranial meningiomas.  相似文献   
42.
RATIONALE AND OBJECTIVES: Endowed with sufficient diagnostic accuracy, electron beam computed tomography angiography (CTA) is being increasingly used to evaluate coronary arteries. However, data on direct comparisons with nuclear myocardial perfusion studies are limited. In this study, we sought to compare the accuracies of CTA and myocardial perfusion imaging (MPI) for identifying symptomatic patients with hemodynamically significant obstructive coronary artery disease (CAD). MATERIALS AND METHODS: In a single-center study, symptomatic outpatients who were scheduled for cardiac catheterization were prospectively enrolled. Only patients with exertional angina or dyspnea were included. After fulfilling the inclusion criteria, 30 patients were enrolled in the study (mean age 54 +/- 9 years and 70% males). Patients underwent MPI, CTA including coronary artery calcification (CAC) measure, and invasive coronary angiography for evaluation of obstructive coronary artery disease. Significant CAD was defined as >50% left main artery stenosis or >70% stenosis of any other epicardial vessel by invasive angiography. The sensitivities, specificities and predictive values of MPI, CAC, and CTA were analyzed per patient RESULTS: CTA demonstrated significant higher sensitivity than MPI (95% vs. 81%, P < .05). CTA demonstrated significantly higher specificity than both MPI (89% versus 78%, P = .04) and CAC (56%, P = .002). CTA also performed better in a per-vessel analysis (sensitivity 94%, specificity 96%) than both nuclear and CAC. There were no significant differences between the sensitivities and specificities of MPI and CAC. CONCLUSION: CTA accurately detects obstructive CAD in symptomatic patients and may be more accurate than MPI or CAC assessment. Larger studies in a more diverse population are needed.  相似文献   
43.
Effect of noise reduction filters on chest computed tomographic (CT) images acquired with 50% radiation dose reduction was evaluated. Two sets of images were acquired with multi-detector row CT at standard (220-280 mA) and 50% reduced (110-140 mA) tube current at the level of the carina. After postprocessing with six noise reduction filters, images were compared with baseline standard-dose images for noise, sharpness, and contrast in lungs, mediastinum, and chest wall. Quantitative image noise was measured in descending thoracic aorta. Modulation transfer functions were calculated from CT images of 50-microm wire. Noise reduction filters reduced image noise on low-radiation-dose chest CT images, with some compromise in image sharpness and contrast assessed qualitatively, and slightly altered modulation transfer function at higher spatial frequencies.  相似文献   
44.
We report a rare case of bilateral multiligament knee injury in an 18-year-old female employed in garment industry. Patient was wearing salwar kameez and dupatta while operating an electric laundry machine. In this case we discuss a peculiar mechanism of injury caused due to wearing dupatta near working site and suggest simple preventive measures.  相似文献   
45.
Prosthodontic methods to correct anterior reverse articulation (also known as anterior cross-bite) can be extremely challenging. This clinical report describes the interdisciplinary management of an adult female patient with a history of chronic periodontitis who presented with reverse articulation in the left canine region. While the patient desired a quick, highly esthetic solution, she was counseled to first undergo orthodontic treatment. After completion of orthodontics, prosthodontic treatment comprised of bleaching therapy, porcelain veneers, and all-ceramic crowns. Periodontal maintenance therapy was also performed during the treatment period. The case portrays the significance of interdisciplinary care and discusses the importance of close communication among specialties.  相似文献   
46.
AIM: To identify their diagnostic and prognostic clinical characteristics in a large series.METHODS: Retrospective review of clinicopathologic and imaging characteristics of patients diagnosed with lymphoepithelial cysts and cystic lymphangiomas of the pancreas at Massachusetts General Hospital.RESULTS: Twelve patients were identified between 1/1/1997 and 8/1/2007. Their median age was 55.5 years(range 19-78 years), and 6 were females. The le-sion was incidentally discovered in half of the patients.Contrast enhanced computed tomography demonstrat-ed that the cysts had thin walls, without calcifications, pancreatic duct dilation or pancreatic parenchyma inva-sion. Endoscopic ultrasound with fine needle aspiration(EUS/FNA) confirmed the diagnosis of a lymphoepithe-lial cyst in 3 patients, one of whom was spared an op-eration and continues to do well after 6 years. Eleven patients had a resection: 3 pancreaticoduodenecto-mies, 7 distal pancreatectomies, and 1 enucleation. The median size of the cysts was 3 cm(range 2-20 cm). At a median follow-up of 57 mo no recurrences or other pancreas-related conditions occurred.CONCLUSION: Lymphoepithelial cysts and cystic lymphangiomas of the pancreas can be diagnosed with a combination of contrast-enhanced computed tomog-raphy scans and EUS/FNA. If the lesion is asymptom-atic, an operation might be avoided.  相似文献   
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Orbital hydatid disease is rare, even in endemic areas. We present a case of disseminated hydatid disease involving the orbit, spleen, lung and liver in a lady aged 35 years. Based on a typical clinical presentation, presence of eosinophilia, a positive indirect haemagglutination test for hydatid disease and presence of similar disseminated, anechoic cystic masses in the liver, lung, spleen and orbit on imaging studies, the diagnosis of hydatid cyst was seriously considered before surgery. Aspiration of the cyst, followed by cryo-extraction of the cyst wall through transconjunctival route was safely performed. Histopathological examination confirmed the diagnosis. In conclusion, multisystemic involvement of liver, lung and spleen in a case of orbital hydatid cyst has never been reported before. The surgical technique adopted in this case is safe and effective.  相似文献   
50.
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