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101.
Quinlan DJ  Alikhan R  Gishen P  Sidhu PS 《Radiology》2003,228(2):443-448
PURPOSE: To retrospectively review bilateral venograms free of thrombus to evaluate the frequency and types of variations seen in venous anatomy. MATERIALS AND METHODS: A retrospective review of 404 bilateral (808 limbs) lower limb venograms obtained from medical patients participating in a thromboprophylaxis clinical trial and found to be free of thrombus was performed. Venograms were evaluated according to predetermined criteria for the presence of duplication of vessels and inter- and intraindividual variations in venous anatomy. Variations were assessed with analysis of variance and chi2 tests. RESULTS: Two vessels were seen in the popliteal fossa on 337 (42%) of 808 venograms, and 41 (5%) were true duplicated popliteal veins. There were 253 (31%) duplicated superficial femoral veins (SFVs), with 12 (1.5%) being complex duplicated systems. Of 265 duplicated SFVs, 138 (52%) began in the midthigh region and 80 (30%), in the adductor canal region. The duplicated vessel was medial to the main SFV in 122 (46%), lateral in 131 (49%), and both (ie, triplications) in 12 (4.5%). The length of the duplicated SFV ranged from 1 to 35 cm; 6-15 cm was the most common length in 162 (62%) SFVs. There was no significant association between the incidence of anatomic variations and age or sex (P >.1). The presence of multiple vessels in one leg was strongly correlated with the probability of occurrence in the other leg (P <.001). CONCLUSION: Variations in lower limb venous anatomy are common and have important implications for the US diagnosis of deep vein thrombosis.  相似文献   
102.
103.
Fetal diastematomyelia is a rare form of spinal dysraphism that is characterized by a complete or incomplete division of the spinal cord by an osseous or fibrocartilaginous septum. A case of diastematomyelia, which was detected on the routine third trimester detailed ultrasound scan, is presented. The diagnosis was based on the detection of an echogenic focus in the posterior aspect of the spine in association with widening of the interpedicular vertebral space. The case illustrates that diastematomyelia can occur in the absence of overt spina bifida and that prenatal detection will allow timely postnatal investigation and treatment. Prenatal literature is further reviewed to assess the clinical significance of this finding.  相似文献   
104.
A rare case of alteration in measured pulse oximetry during a lymphatic mapping procedure for cervical carcinoma is reported. Over a 5-min period following injection of perilesional Lymphazurin 1% dye (3 ml total), a profound pulse oximetry desaturation was observed. Concomitant arterial blood gas determinations confirmed patient's well-being. Interaction of this agent's absorptive spectroscopy and wavelengths used to measure oxygen saturation by commercial pulse oximetry devices is suspected.  相似文献   
105.
Ultrasound of the carotid and vertebral arteries   总被引:5,自引:0,他引:5  
Ultrasound plays an important role in the assessment of carotid arterial disease, complimentary to other imaging modalities. However, ultrasound does have limitations, not least the requirement of a high degree of operator skill. Recent advances in ultrasound technology will strengthen its role by improving accuracy. This review discusses the role of ultrasound in assessing the carotid arterial system with emphasis on evaluating stenosis.  相似文献   
106.
BACKGROUND: Cataract extraction constitutes the largest surgical workload in ophthalmic units throughout the world. Extracapsular cataract extraction (ECCE), through a large incision, with insertion of an intraocular lens has been the most widely used method from 1982 until recently. Technological advances have led to the increasing use of phacoemulsification (Phako) to emulsify and remove the lens The technique requires a smaller incision, but requires substantial capital investment in theatre equipment. In this randomised trial we assessed the clinical outcomes and carried out an economic evaluation of the two procedures. METHODS: In this two centre randomised trial, 232 patients with age related cataract received ECCE, and 244 received small incision surgery by Phako. The main comparative outcomes were visual acuity, refraction, and complication rates. Resource use was monitored in the two trial centres and in an independent comparator centre. Costs calculated included average cost per procedure, at each stage of follow up. RESULTS: Phako was found to be clinically superior. Surgical complications and capsule opacity within 1 year after surgery were significantly less frequent, and a higher proportion achieved an unaided visual acuity of 6/9 or better (<0.2 logMAR) in the Phako group. Postoperative astigmatism was more stable in Phako. The average cost of a cataract operation and postoperative care within the trial was similar for the two procedures. With the input of additional spectacles for corrected vision at 6 months after surgery, the average cost per procedure was pound359.89 for Phako and pound367.57 for ECCE. CONCLUSION: Phako is clinically superior to ECCE and is cost effective.  相似文献   
107.
EDITORIAL COMMENT: We accepted this case report for publication because, apart from being interesting, it raises the question of the appropriate hormone replacement therapy after bilateral oophorectomy (usually with hysterectomy) has been performed when there is evidence of endometriosis. Menopausal symptoms in these women can be relieved by oestrogen therapy without return of pelvic pain or dyspareunia. The authors report a case of endometrial-like carcinoma in a woman with known endometriosis after a hysterectomy and prolonged unopposed oestrogen therapy. Although this is a solitary case report, the authors explain that there are 8 others in the literature where malignancy occurred in extraovarian endometriosis after bilateral oophorectomy associated with unopposed oestrogen. One of our reviewers commented that a combination of oestrogen and progestogen should always be considered when prescribing hormone replacement therapy in women with a known history of endometriosis, following total hysterectomy and bilateral oophorectomy.  相似文献   
108.
109.
Cardiac papillary fibroelastomas are benign tumors that usually arise from the valvular endocardium. They are clinically important because of their propensity to embolize. We describe, to the best of our knowledge, the first reported case of a papillary fibroelastoma arising from the left atrial appendage, giving rise to multiple cerebral embolic events. The tumor was excised surgically, with no further embolic events.  相似文献   
110.
Fetal diastematomyelia is a rare form of spinal dysraphism that is characterized by a complete or incomplete division of the spinal cord by an osseous or fibrocartilaginous septum. A case of diastematomyelia, which was detected on the routine third trimester detailed ultrasound scan, is presented. The diagnosis was based on the detection of an echogenic focus in the posterior aspect of the spine in association with widening of the interpedicular vertebral space. The case illustrates that diastematomyelia can occur in the absence of overt spina bifida and that prenatal detection will allow timely postnatal investigation and treatment. Prenatal literature is further reviewed to assess the clinical significance of this finding.  相似文献   
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