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Chronic contained rupture of an abdominal aortic aneurysm (AAA) is a rare event that is difficult to diagnose due to the atypical and chronic symptoms. We report a case of chronic contained rupture of AAA mimicking a retroperitoneal tumor in a 36-year-old man. The patient presented with weight loss and chronic lower abdominal pain, and was referred to our clinic with a suspected retroperitoneal tumor. Abdominal computed tomography (CT) revealed a distinct mass measuring 15 x 10 x 10 cm in the left retroperitoneal space, involving the abdominal aorta. One week later he experienced sudden abdominal pain radiating to the back. He was subsequently diagnosed with ruptured AAA and aortic dissection. The patient received implantations of both common iliac arteries to the abdominal aorta using Y-grafts and an ascending-to-descending aortic graft in a two-stage operation. His recovery from surgery was uneventful.  相似文献   
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BACKGROUND: Primary adenocarcinomas of the vulva have been classified as sweat gland carcinomas, extramammary Paget's disease, and primary breast carcinomas of the vulva. They share some common histopathologic features. METHODS: We describe a 72-year-old Japanese woman with apocrine carcinoma of the vulva and local lymphatic metastasis. RESULTS: The patient presented with a bruise on her inguinal area. Physical examination revealed a 4 cm x 7 cm, dark-red, irregularly elevated tumor on the left labium majora. Dome-shaped, flesh-colored, small papulovesicles were scattered on the abdomen, accompanied by erythema and induration. The lesion showed a band-like arrangement. General examination revealed multiple bone metastases, particularly in the spine. Microscopic examination revealed a moderately differentiated adenocarcinoma with signet ring cells. A few pagetoid clear cells were present in the hypertrophic epidermis. The peripheral papulovesicles demonstrated the same histopathologic view as in inflammatory and telangiectatic, metastatic breast carcinoma. Tumor cells were positive for various ductal and glandular markers. Estrogen and progesterone receptors were not expressed. Ultrastructural findings suggested differentiation towards apocrine or mammary glands because of the presence of an apocrine process and electron-dense mucous granules. The patient died in spite of combination chemotherapy and irradiation therapy. CONCLUSIONS: We report a rare case of apocrine carcinoma of the vulva in a band-like arrangement with local lymphatic metastasis which showed the clinical and histopathologic characteristics of inflammatory and telangiectatic carcinoma.  相似文献   
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BACKGROUND: The Prostar XL is a hemostasis device designed to percutaneously close the arterial puncture site with two nonabsorbable sutures. The Early Discharge and Economical effectiveness study for New hemostasis device (EDEN) trial, which was performed in Japan, showed that the Prostar XL device shortened time to hemostasis, time to ambulation and the average length of hospital stay, and decreased local vascular complications. However, the ooze of blood from the puncture site incision requires relatively longer time to ambulation. OBJECTIVES: The Perclose AcceleRated Ambulation and DISchargE (PARADISE) trial was performed to assess the effectiveness of the Prostar XL device on patient comfort, shortened time to ambulation and discharge from hospital by minimizing the oozing problem. METHODS: This multicenter, non-randomized registry was designed to compare times to hemostasis, ambulation and discharge, as well as the incidence of peripheral vascular complications in Prostar XL patients with the conventional manual compression group in the EDEN trial. Hydrochloride lidocaine containing 1% epinephrine was used as local anesthesia to reduce blood oozing. RESULTS: Between September 1999 and March 2000, a total of 109 patients were enrolled in this study. The closure device was successfully placed in 108 of 109 attempts. Time to hemostasis was significantly less than with the conventional manual compression group in the EDEN trial. Times to ambulation and discharge were significantly less than with the Prostar XL and conventional manual compression groups in the EDEN trial. CONCLUSION: We conclude that the Prostar XL device plus hydrochloride lidocaine containing 1% epinephrine as local anesthesia appears to be a safe and effective method to achieve hemostasis, and to improve times to ambulation and discharge after interventional procedures.  相似文献   
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PURPOSE: Attenuation correction with an X-ray CT image is a new method to correct attenuation on SPECT imaging, but the effect of the registration errors between CT and SPECT images is unclear. In this study, we investigated the effects of the registration errors on myocardial SPECT, analyzing data from a phantom and a human volunteer. METHODS: Registerion (fusion) of the X-ray CT and SPECT images was done with standard packaged software in three dimensional fashion, by using linked transaxial, coronal and sagittal images. In the phantom study, an X-ray CT image was shifted 1 to 3 pixels on the x, y and z axes, and rotated 6 degrees clockwise. Attenuation correction maps generated from each misaligned X-ray CT image were used to reconstruct misaligned SPECT images of the phantom filled with 201Tl. In a human volunteer, X-ray CT was acquired in different conditions (during inspiration vs. expiration). CT values were transferred to an attenuation constant by using straight lines; an attenuation constant of 0/cm in the air (CT value = -1,000 HU) and that of 0.150/cm in water (CT value = 0 HU). For comparison, attenuation correction with transmission CT (TCT) data and an external gamma-ray source (99mTc) was also applied to reconstruct SPECT images. RESULTS: Simulated breast attenuation with a breast attachment, and inferior wall attenuation were properly corrected by means of the attenuation correction map generated from X-ray CT. As pixel shift increased, deviation of the SPECT images increased in misaligned images in the phantom study. In the human study, SPECT images were affected by the scan conditions of the X-ray CT. CONCLUSION: Attenuation correction of myocardial SPECT with an X-ray CT image is a simple and potentially beneficial method for clinical use, but accurate registration of the X-ray CT to SPECT image is essential for satisfactory attenuation correction.  相似文献   
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This review article describes a method for quantifying heterogeneous distribution on Technegas (99mTc-carbon particle radioaerosol) SPECT images by three-dimensional fractal analysis (3D-FA). Technegas SPECT was performed to quantify the severity of pulmonary emphysema. We delineated the SPECT images by using five cut-offs (15, 20, 25, 30 and 35% of the maximal voxel radioactivity), and measured the total number of voxels in the areas surrounded by the contours obtained with each cut-off level. We calculated fractal dimensions from the relationship between the total number of voxels and the cut-off levels transformed into natural logarithms. The fractal dimension derived from 3D-FA is the relative and objective measurement, which can assess the heterogeneous distribution on Technegas SPECT images. The fractal dimension strongly correlate pulmonary function in patients with emphysema and well documented the overall and regional severity of emphysema.  相似文献   
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