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111.
112.
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   
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114.
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   
115.
Background: An outbreak of food poisoning in a military establishment mess was investigated and remedial measures suggested.  相似文献   
116.
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   
117.
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   
118.
BACKGROUND: Little is known about the infrastructure to train gastroenterologists in capsule endoscopy. The level of capsule endoscopy exposure among trainees in the United Kingdom or Europe has also not been quantified. AIMS AND METHODS: To assess the ability of 10 gastroenterology trainees with endoscopy experience to interpret 10 capsule endoscopy videos against five medical students, with an expert in capsule endoscopy as the gold standard. Parameters assessed included gastric emptying time, small bowel transit and the diagnosis made. A questionnaire survey assessed the level of capsule endoscopy exposure among United Kingdom trainees. RESULTS: Trainees were better at determining the gastric emptying time (p=0.013) and more likely to record true positives compared to the students (p=0.037). They were also less likely to record false positives (p=0.005) and more likely to reach the correct diagnosis (p=0.001, OR 3.6, CI 1.8-7.4). Our survey found that, 65% of trainees had prior exposure to capsule endoscopy but only 13% had done capsule endoscopy reporting. Sixty seven percent felt capsule endoscopy should be incorporated into their training. CONCLUSION: This study has shown that prior endoscopic experience enables trainees to interpret capsule endoscopy more accurately than medical students. However, there is a demand for focussed training which would enable trainees to reliably interpret pathology on capsule endoscopy.  相似文献   
119.
GOALS: To characterize beta blocker therapy for the primary and secondary prevention of variceal hemorrhage. BACKGROUND: Variceal hemorrhage is one of the more frequent and severe complications of portal hypertension due to liver disease. Beta blocker therapy has been demonstrated to decrease risk of first bleed in patients with evidence of varices and recurrent bleeding and mortality in patients with history of prior variceal hemorrhage. STUDY: A total of 106 patients with liver disease hospitalized with suspected variceal hemorrhage were retrospectively reviewed. RESULTS: Half of patients had known varices, 44 (41.5%) of whom had experienced prior variceal hemorrhage. Only 21 (20%) were receiving beta blocker therapy at admission and 41 (48%) at discharge. The majority were not receiving therapy for primary prophylaxis (94%). Specific characteristics associated with beta blocker use could not be identified, although more patients with history of greater than two variceal hemorrhages were receiving beta blocker at admission (73% vs. 41%, P = 0.04) CONCLUSIONS: This study suggests that liver disease patients with varices are often not receiving beta blocker therapy to reduce risk of first or subsequent variceal hemorrhage. Opportunity exists to optimize use of this proven prophylactic treatment and bridge an apparent gap in standard of care.  相似文献   
120.
Predictive factors of urinary retention following prostate brachytherapy   总被引:4,自引:0,他引:4  
PURPOSE: To evaluate the incidence and duration of urinary retention requiring catheterization and the factors predictive for these end points. METHODS AND MATERIALS: Two hundred eighty-two patients treated with prostate brachytherapy alone were evaluated. Clinical and treatment-related factors examined included: age, baseline International Prostate Symptom Score (IPSS), presence of comorbidity, planning ultrasound target volume (PUTV), postimplant prostate CT scan volume, the CT:PUTV ratio, number of seeds inserted, number of needles used, use of neoadjuvant hormones, procedural physician, clinical stage, Gleason score, and pretreatment PSA. Dosimetric quality indicators were also examined. RESULTS: Urinary obstruction after prostate brachytherapy developed in 43 (15%) patients. The median duration of catheter insertion was 21 days (mean 49, range 1-365). Univariate analysis demonstrated that presence of diabetes, preimplant volume, postimplant volume, CT:PUTV ratio, number of needles, and dosimetric parameters were predictive for catheterization. However, in multivariate analysis, only the baseline IPSS, CT:PUTV ratio, and presence of diabetes were significant independent predictive factors for catheterization. CONCLUSION: Baseline IPSS was the most important predictive factor for postimplantation catheterization. The extent of postimplant edema, as reflected by the CT:PUTV ratio, predicted for need and duration of catheterization. The presence of diabetes was predictive for catheterization, but may relate to the absence of prophylactic steroids, and therefore requires further evaluation.  相似文献   
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