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111.
Diagnosis of liver infestation by Echinococcus alveolaris (EA) is based on serological and radiological findings. In this report, we present a 15-year-old girl with atypical hepatic EA infestation showing central punctate calcifications and contrast enhancement on the portal and late phases of CT and MRI. CT showed a hypodense mass involving more than half of the liver with prominent central calcifications. MRI revealed hypointense signal of the infiltrative mass on both T1- and T2-weighted images. Contrast enhancement is a unique finding in hepatic EA infestation that may cause difficulties with diagnosis. MRI may provide invaluable information in the diagnosis of EA infestation of the liver, either by disclosing the infiltrative pattern of infestation without significant effect to vascular structures, or by the signal characteristics.  相似文献   
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We describe herein the use of MR fluoroscopic guidance in the drainage of abscess cavities. We percutaneously drained 12 brain abscesses in 11 patients. A 0.3T open MR imaging system was used. Sixteen drainages were performed in 12 abscesses. Repeat drainage was needed in three recurrences and one residual lesion. No serious complications were seen. MR fluoroscopy-guided percutaneous brain abscess drainage in an open MR imaging system is feasible.  相似文献   
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INTRODUCTION: The aim of the study is to investigate the efficacy of the magnetic resonance fluoroscopy in the diagnosis and staging of the pelvic prolapse. MATERIALS AND METHODS: The study consisted of 46 patients who were known to have pelvic prolapses from their vaginal examination. Thirty women who underwent vaginal exam and shown not have pelvic prolapse were selected as a control group. Firstly, pelvic sagittal FSE T2 weighted images of all the women were acquired in 0.3 T open MR equipment than sagittal MR-fluoroscopic images using spoiled gradient echo sequences were obtained during pelvic strain. Physical examination and MR-fluoroscopic findings were compared. The relationship between the stages of prolapse established by both of the methods was evaluated statistically with Pearson's correlation analysis. RESULTS: Physical examination and MR findings were very concordant in the diagnosis of pelvic prolapse and statistical correlations in the stages of prolapse were established between both of the methods (P<0.01 for anterior and middle comportment, P<0.05 for posterior comportment). CONCLUSION: We conclude that MR-fluoroscopy is a non-invasive, easily applied, dynamic useful method without contrast agent in the diagnosis and staging of pelvic organ prolapse.  相似文献   
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Laparoscopic adhesiolysis for small bowel obstruction   总被引:15,自引:0,他引:15  
BACKGROUND: Historically, laparotomy and open adhesiolysis have been the treatment for patients requiring surgery for small bowel obstruction. Laparoscopic adhesiolysis has not gained wide acceptance. The indications and outcomes of laparoscopic adhesiolysis for small bowel obstruction are not well established. The purpose of this paper is to review the literature on laparoscopic adhesiolysis for small bowel obstruction and to discuss patient selection, surgical technique, and outcomes. DATA SOURCES: Medline search from 1980 to 2002. CONCLUSIONS: Laparoscopic adhesiolysis has been shown to be safe and feasible in experienced hands. For selected patients, laparoscopic adhesiolysis offers the advantages of decreased length of stay, faster return to full activity, and decreased morbidity. Patient selection and surgical judgment appear to be the most important factors for a successful outcome.  相似文献   
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Managed behavioral health care organizations (MBHOs) often profile hospitals on length of stay (LOS) and other performance measures. However, previous research has suggested that most of the variation in utilization for general medical conditions is attributable to case-mix indicators and random sources rather than individual providers. Hospital discharge data are used to estimate hierarchical linear models, where hospitals and physicians within hospitals are treated as a random effect. The goal was to determine the intraclass correlation coefficient (ICC) for psychiatric LOS for hospitals and for physicians before and after making case-mix adjustments. After controlling for case-mix, the hospital ICCs for depression, schizophrenia, and bipolar disorder show that 32%, 36%, and 11% of the variation in LOS, respectively, can be attributed to hospitals, while 7%, 5%, and 6% of the variation in LOS, respectively, can be attributed to physicians or provider practice. Unlike health services for other conditions, the variation in LOS for inpatient psychiatric treatment of depression and schizophrenia is quite dependent upon hospitals.  相似文献   
117.
OBJECTIVE: This study analyzed the impact of length of stay for inpatient treatment of psychiatric disorders on readmission rates. METHODS: Hospitalization data were obtained from the MarketScan data set collected by Medstat. The instrumental variable method, an econometric technique, was used to estimate the impact of length of stay on the rate of readmission for 5,735 persons who had at least one discharge with a primary diagnosis of a psychiatric disorder during 1997 and 1998. RESULTS: Decreasing length of stay below ten days led to an increase in the readmission rate during the 30 days after discharge. Decreasing the length of stay from seven to six days increased the expected readmission rate from.04 to.047 (17.5 percent), whereas decreasing length of stay from four to three days increased the readmission rate from.09 to.136 (51.1 percent). CONCLUSION: Decreasing length of stay for inpatient psychiatric treatment increased the readmission rate. The use of instrumental variables could help better estimate the value of mental health services when using observational data.  相似文献   
118.
The aim of the present paper is to evaluate how the use of decision models in the review of portal images can eliminate systematic set-up errors during conformal therapy. Sixteen patients undergoing four-field irradiation of prostate cancer have had daily portal images obtained during the first two treatment weeks and weekly thereafter. The magnitude of random and systematic variations has been calculated by comparison of the portal image with the reference simulator images using the two-dimensional decision model embodied in the Hotelling's evaluation process (HEP). Random day-to-day set-up variation was small in this group of patients. Systematic errors were, however, common. In 15 of 16 patients, one or more errors of >2 mm were diagnosed at some stage during treatment. Sixteen of the 23 errors were between 2 and 4 mm. Although there were examples of oversensitivity of the HEP in three cases, and one instance of undersensitivity, the HEP proved highly sensitive to the small (2-4 mm) systematic errors that must be eliminated during high precision radiotherapy. The HEP has proven valuable in diagnosing very small (<4 mm) errors. When combined with the potential for rapid diagnosis of larger (>4 mm) systematic errors using one-dimensional decision models, HEP can eliminate the majority of systematic errors during the first 2 treatment weeks.  相似文献   
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