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991.
Robert C. Knowlton MD Nicholas D. Lawn FRACP James M. Mountz MD PhD Ojha Buddhiwardhan MD Suzanne Miller RN BSN Jorge G. Burneo MD Ruben I. Kuzniecky MD 《Journal of neuroimaging》2004,14(4):324-330
PURPOSE: To examine the application of statistical parametric mapping (SPM) to analyze ictal single-photon emission computed tomography (SPECT) scans in surgical candidates with extratemporal lobe epilepsy. METHODS: The authors selected patients who underwent successful ictal SPECT acquisition in the process of surgical treatment of intractable partial epilepsy. Thirteen patients were identified who met inclusion criteria for confident seizure localization from either intracranial electroencephalogram recordings or epilepsy surgery outcome. In these cases, ictal scans were registered to an in-house-developed normal SPECT atlas composed of 14 spatially normalized brains of normal subjects. SPM96 was used to test on a voxel-by-voxel basis for statistically significant increases in blood flow associated with each patient's ictal scan. The results were then mapped back onto the patient's magnetic resonance image (MRI) for final interpretation. Statistical parametric mapping (SPM) analysis of ictal SPECT scans was compared to both conventional visual interpretation and the analysis of subtraction ictal SPECT co-registered to MRI (SISCOM). RESULTS: Ten of 13 patient scans showed localizing focal ictal increases in regional cerebral blood flow, all of which were concordant with ultimate epilepsy localization. Of the 3 cases not localized with SPM, 1 was localized by conventional visual interpretation and another, not localized by visual interpretation, was correctly localized with SISCOM. Two cases not localized by SISCOM were localized by both visual and SPM analysis. CONCLUSIONS: This work provides supportive evidence for proof of principle that SPM can be used to provide objective, accurate analysis of ictal SPECT scans in patients with extratemporal lobe epilepsy. 相似文献
992.
993.
The acromioclavicular joint is a potential source of pain in the shoulder. There are a variety of disorders that can affect this joint, including distal clavicle osteolysis, posttraumatic arthritis, osteoarthritis, and rheumatoid arthritis. Nonoperative treatment for this condition with nonsteroidal medication and activity modification can alleviate the pain. When conservative treatment is exhausted, surgical resection of the distal clavicle is often necessary. Arthroscopic resection of the distal clavicle preserves the acromioclavicular ligaments to prevent postoperative distal clavicle instability. The procedure is performed in either the beach chair or lateral position and requires the use of a shaver, electrocautery, and a burr for soft tissue and debridement and bone resection. 相似文献
994.
995.
Fenton Schaffner MD 《Digestive diseases and sciences》1991,36(9):1282-1286
Regeneration of human liver was long suspected to occur. It was proven in animals 100 years ago but could not be demonstrated in man until liver biopsy and modern hepatic tests became available. Structural changes in the regenerating liver mainly concern the arrangement of liver cell plates and the size and appearance of hepatocytic nuclei. A return to normalcy in test results depends on the factors responsible for regeneration since various test results change at different rates. Mass, estimated by imaging procedures, is restored parallel with the return of function. Shape is not restored but the pressure of neighboring organs and structures molds the growing remnant so that it almost resembles the original. Factors regulating regeneration in man are beginning to be recognized as they have been in animals. The hope is that regeneration can be accelerated or that cells can be transplanted to replace those lost. 相似文献
996.
997.
磁共振成像对胸膜外脂肪显示的研究 总被引:1,自引:0,他引:1
目的:研究MRI对正常及异常胸膜外脂肪显示的价值。材料和方法:对21例健康志愿者进行了MRI化学位移同相位成像、反相位成像、T1WI、T2WI及STIR序列扫描,并对胸膜外脂肪的绝对信号强度及信号强度比进行比较分析,同时还对20例累及胸膜外脂肪的病人进行检查。结果:在MRI各序列中,化学位移反相位成像显示胸膜外脂肪最佳,各序列绝对信号强度没有差别,而信号强度比存在差异。异常的胸膜外脂肪可以表现为移位、受压、中断、增厚及信号改变。结论:MRI可以作为观察正常及异常胸膜外脂肪的有效检查方法。 相似文献
998.
999.
1000.
Marcos Daccarett MD Gustavo Espinosa MD FACR Fred Rahimi DPM Christopher M. Eckerman DPM Shelley Wayne-Bruton DPM Mark Couture DPM Jason Rosenblum DPM 《The Journal of foot and ankle surgery》2002,41(6):372-378
Dactylolysis spontanea is an idiopathic condition affecting the fifth toe, and sometimes other toes, that is frequently bilateral, with lesions in different stages. Between 1977 and 1999, a total 6000 radiographic studies of the feet were reviewed in a mainly African American population in Chicago, Illinois. After an initial screening based on the Cole criteria, 581 patients were selected and re-examined, and amplification techniques were performed. After reviewing the complementary exams, 102 patients were diagnosed with dactylolysis spontanea or ainhum. Soft-tissue constriction was the most frequently presented radiological sign on the initial screening. Kurtosis at the digit plantar fold and marked rotation of the fifth toe were normal findings in asymptomatic patients. Demographics, comorbidities, and radiological findings were analyzed in the selected population. Associated diseases occurring in these patients appeared to have no specific etiologic correlation with ainhum. African Americans and the dark-skinned population are affected exclusively by this condition, presumably due to the fibrogenic tendency of these individuals. Early diagnosis and accurate staging of ainhum are facilitated by radiological examination of the feet. The findings suggest that this condition is underdiagnosed and overlooked because its low prevalence and variable clinical presentations that might mimic more common etiologies, including localized trauma. 相似文献