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61.
A double-contrast upper gastrointestinal examination on a woman who had undergone endoscopic heater probe therapy one day earlier for multiple arteriovenous malformations revealed shallow, irregular, and linear ulcers at the sites of heater probe coagulation. Multiple shallow ulcers may therefore develop as a direct complication of heater probe therapy. Radiologists should be aware of this complication to avoid diagnostic confusion in these patients.  相似文献   
62.
PURPOSETo analyze the MR characteristics of a series of patients with esthesioneuroblastoma and discuss the typical surgery and its postoperative MR appearance.METHODSThe MR studies of 15 patients with the pathologic diagnosis of esthesioneuroblastoma (also known as olfactory neuroblastoma) were retrospectively reviewed and correlated with CT and surgical findings. The postoperative MR studies of 10 patients who underwent craniofacial resection were also reviewed.RESULTSIn all cases the tumors arose in the superior nasal cavity and extended into the ethmoid cells. In some instances the tumors extended into the other paranasal sinuses, orbits, anterior cranial fossa, and cavernous sinus. The tumors were typically expansile and destructive in their growth patterns. Compared with brain gray matter, the tumors were hypointense on T1-weighted images and isointense to hyperintense on T2-weighted images. Nine tumors were heterogeneous and 6 were homogeneous. Contrast enhancement ranged from mild to marked. MR was useful for characterizing the various tissues and distinguishing fluid in the postoperative nasal cavity.CONCLUSIONSEsthesioneuroblastoma, although an uncommon tumor, may be suspected in lesions of the superior nasal cavity demonstrating both expansile and destructive growth properties. The MR findings are otherwise nonspecific. MR is the imaging modality of choice for depicting local tumor extension and evaluating for recurrence after craniofacial resection.  相似文献   
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64.
BACKGROUND: There is a lack of information from Canadian hospitals on the role of hospital characteristics such as procedure volume and teaching status on the survival of patients who undergo major cancer resection. Therefore, we chose to study these relationships using data from patients treated in Ontario hospitals. METHODS: We used the Ontario Cancer Registry from calendar years 1990-2000 to obtain data on patients who underwent surgery for breast, colon, lung or esophageal cancer or who underwent major liver surgery related to a cancer diagnosis between 1990 and 1995 in order to assess the influence of volume of procedures and teaching status of hospitals on in-hospital death rate and long-term survival. For each disease site and before observing patient outcomes data, volume cut-off points were selected to create volume groups with similar numbers of patients. Teaching hospitals were those directly affiliated with a medical school. Logistic regression and proportional hazards models were used to consider the clustering of data at the hospital level and to assess operative death and long-term survival. We also used 4 measures to gauge the degree of procedure regionalization across the province including (1) the number of hospitals performing a procedure; (2) the percentage of patients treated in teaching hospitals; (3) the percentage of rural patients treated in higher volume procedure hospitals; and (4) median distances travelled by patients to receive care. RESULTS: The number of patients in our cohorts who underwent resection of the breast, colon, lung, esophagus or liver was 14 346, 8398, 2698, 629 and 362, respectively. Surgery in a high-volume versus a low-volume hospital did not have a statistically significant influence on the odds of operative death for patients who underwent colon, liver, lung or esophageal cancer resection. The risk of long-term death was increased in low-volume versus high-volume hospitals for patients who underwent resection of the breast (hazard ratio [HR] 1.2, 95% confidence interval [95% CI] 1.0-1.4, p < 0.05), lung (HR 1.3, 95% CI 1.1-1.6, p < 0.01) and liver (HR 1.7, 95% CI 1.0-2.7, p = 0.04). There were no significant differences in the odds of operative (in-hospital) death or risk of long-term death among patients treated in teaching compared with nonteaching hospitals. There was more regionalization of liver, lung and esophageal operations versus breast and colon operations. CONCLUSIONS: Increased hospital procedure volume correlated with improved longterm survival for patients in Ontario who underwent some, but not all, cancer resections, whereas hospital teaching status had no significant impact on patient outcomes. Across the province, further regionalization of care may help improve the quality of some cancer procedures.  相似文献   
65.
Lymphangioma presenting as a small renal mass during childhood.   总被引:1,自引:0,他引:1  
Renal lymphangioma is a very rare lesion. A case of lymphangioma that presented as a small, hyperechoic renal mass on sonography in a child is reported. On CT, the lesion appeared as a low-density, enhancing renal mass. Despite its rarity, lymphangioma should be considered in the differential diagnosis of such a lesion. A suspected lymphangioma may be evaluated by percutaneous biopsy.  相似文献   
66.
A 60 year male, orthotopic heart transplant recipient developed a fatal left ventricular outflow obstruction secondary to thrombus at 38 months post transplant. Although he had episodes of mild to moderate rejection at 2 and 16 months post transplant, subsequent biopsies were negative and annual cardiac catheterizations showed mild left ventricular hypokinesis and normal coronary arteries. This case represents a catastrophic complication of transplant rejection and illustrates the problems with identifying rejection using current diagnostic methods.  相似文献   
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68.
The goal of this review is to provide an approach to the diagnosis of pulmonary infections in immunosuppressed patients. First, a framework will be provided to narrow the extensive list of possible infectious and noninfectious pulmonary complications. This can be accomplished by considering the underlying immune defect, the pattern of radiographic presentation, the rapidity of progression of radiographic infiltrates, the typical temporal pattern of infection in specific disease states, and the local epidemiology at one's institution. Next, the yields and potential complications of invasive and noninvasive diagnostic techniques for pulmonary infections are reviewed. Lastly, algorithms, which account for the pattern of radiographic presentation, the primary disease and its underlying immune defect and the anticipated yields and complications of diagnostic procedures, are provided as a suggested plan for the use of diagnostic techniques and the institution of therapy.  相似文献   
69.
Injection therapy for impotence   总被引:1,自引:0,他引:1  
Injection of vasoactive drugs is an effective form of treatment for selected patients with impotence from virtually all causes. The two most commonly employed drugs in the United States are either papaverine alone or various combinations of papaverine and phentolamine. Patients with organic and mixed impotence are best suited for injection treatment, but selected patients with psychogenic impotence also benefit from therapy. After the patient is selected for injection therapy, he undergoes a series of trial injections in the physician's office. The incidence of priapism will be minimized if the initially administered doses are low and the patient is titrated to an appropriate dose level. Uncontrolled trials have revealed that injection treatment produces a satisfactory erection in 65 to 100 per cent of patients for a follow-up period of as long as 2 years with minimal side effects, but the dropout rate is high. If priapism does occur, it almost always responds readily to treatment with aspiration, low doses of an alpha-adrenergic agent, or both. The other common side effects are bruising or ecchymosis and nodule formation at the injection site. This latter complication has not been noted to cause significant abnormal penile curavature necessitating cessation of the program.  相似文献   
70.
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