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941.
A case of vesicouterine fistula in a young woman following caesarean section is presented. The diagnosis was established successfully using heavily T2-weighted MRI which clearly demonstrated fluid within the fistula, obviating the need for conventional radiographic contrast examination. Received: 21 October 1998; Revised: 27 January 1999; Accepted: 1 March 1999  相似文献   
942.
Epiploic appendagitis and segmental omentum infarction are considered to be rare conditions, which may mimic an abdominal surgical emergency. The purpose of our study was to describe clinical findings, US and CT appearance of infarction of an epiploic appendage and omentum, and to determine their epidemiological characteristics and natural history. We retrospectively studied clinical, US and CT findings at hospital admission and follow-up of all patients who were diagnosed at our institution with epiploic appendagitis or omentum infarction between June 1988 and November 1997. We found a relatively high incidence of 40 cases: 20 patients with epiploic appendagitis, 11 with omentum infarction, and 9 in whom it was not possible to discriminate between the both. All 40 patients recovered under conservative treatment without complications. We conclude that US and CT features allow a reliable diagnosis, thereby obviating unnecessary surgery. Discriminating between both conditions is of no practical relevance since treatment and prognosis are identical. Received: 30 November 1998; Revised: 30 March 1999; Accepted: 6 September 1999  相似文献   
943.
The aim of this study was to assess the accuracy of MR in the diagnosis of synovialisation of the anterior cruciate ligament (ACL) compared with arthroscopy. One hundred and forty-nine patients were examined with MR imaging and arthroscopy of the knee. The MR sign used to consider a synovialised ACL consisted of hypointense fibrillar tracts, disrupted and wavily, in its expected course. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV), comparison of proportions (McNemar test) and Kappa values for agreement between MR imaging and arthroscopy were calculated. Of the 133 (89.3 %) ligaments without synovialisation at arthroscopy, 130 accorded with the MR results. Of the 16 (10.7 %) synovialised ligaments, 13 accorded with the MR results. Three false-positive and three false-negative MR diagnoses were identified. The agreement between both techniques was excellent (Kappa = 0.79; p = 0.000), without differences (McNemar test; p = 1). Sensitivity was 0.81, specificity 0.98, PPV 0.98 and NPV 0.81. Magnetic resonance imaging is highly reliability for synovialisation diagnosis. The imaging sign used to diagnose synovialised ACL (hypointense comma-like tracts in its expected course) is reliable. As this reparative process can simulate an intact ligament, knowledge of this sign is important in diagnosing synovialisation of ACL tears so as not to confuse it with normal ACL. Received: 17 June 1998; Accepted: 6 August 1998  相似文献   
944.
The role of self-expanding metallic stents is well established in the palliation of oesophageal stenosis and dysphagia due to primary oesophageal malignancy. However, their role in palliation of dysphagia due to external compressive mediastinal malignancies is not well established. The purpose of this study was to assess the efficacy of self-expanding metallic stents in the palliation of dysphagia due to extrinsic oesophageal compression by mediastinal malignancy. Between January 1995 and January 1998, 21 patients with oesophageal compression due to malignant mediastinal tumours underwent oesophageal stent placement for palliation of dysphagia. Complete data were available in 17 patients (10 men and 7 women). The mean age was 63.5 years (range 46–89 years). A total of 19 stents were placed successfully. The dysphagia grade prior to and after oesophageal stent placement was assessed and the complications documented. Of the 17 patients, 16 reported an improvement in dysphagia. The mean dysphagia score improved from 3.1 prior to treatment to 1.3 after treatment. In 1 patient the stent slipped during placement and another stent was placed satisfactorily. Early complications (within 48 h) in the form of mild to moderate retrosternal chest pain occurred in 5 patients. This was treated symptomatically. Late complications (after 48 h) in the form of bolus impaction occurred in 2 patients. This was successfully treated with oesophagoscopy and removal of bolus. In 2 patients the stent was overgrown by tumour and in one of these an additional stent was placed. In 1 patient incomplete closure of a tracheo-oesophageal fistula was observed. There was no procedure- or stent-related mortality. The mean survival time of this group was 2.1 months. Self-expanding metallic stents can be safely and effectively used in the palliation of dysphagia due to external mediastinal malignancies. Received: 21 October 1998; Revised: 1 February 1999; Accepted: 4 February 1999  相似文献   
945.
Fibroepithelial polyps are the most frequently observed mesenchymal tumors of the renal pelvis. We report on one case of fibroepithelial polyp of the renal pelvis with unusual CT findings of totally cystic structure with septations. Received: 27 July 1998; Revised: 6 January 1999; Accepted: 8 February 1999  相似文献   
946.
In this study, thirty-eight patients with a variety of upper abdominal diseases were examined with three-dimensional time-resolved MR angiography (7 sec/data set). Visualisation of arterial and venous anatomy was excellent in the majority of patients. Moreover, subtraction images could be calculated and organ perfusion could be assessed. It is concluded that this technique opens new perspectives for a comprehensive evaluation of vascular and parenchymal disease. Received: 14 April 1998; Revision received: 23 October 1998; Accepted: 9 November 1998  相似文献   
947.
Tubular ectasia of the rete testis: a potential pitfall in scrotal imaging   总被引:1,自引:0,他引:1  
Tubular ectasia of the rete testis (TERT) is a benign entity due to dilation of the tubules of the rete testis. Most of the time it is discovered incidentally on scrotal sonograms and may be misinterpreted as malignant. This article outlines the diagnostic criteria of TERT, its possible causes, its incidence and its potential evolution. Recognizing this entity owing to its characteristic clinical, sonographic and, if necessary, MRI features is important to avoid unnecessary surgery or biopsies. Received: 4 August 1998; Revised: 15 April 1999; Accepted: 19 April 1999  相似文献   
948.
Few studies related to parity address the changes in anorectal function in women. Since the majority of patients with rectal prolapse are women, we undertook this study to assess the role of parity in the development of rectal prolapse. We retrospectively reviewed defecography studies performed on 354 female patients over a 10-year period. Studies noting the presence of intra-anal and external rectal prolapse (full thickness protrusion of the rectum into and through the anal sphincter) were reviewed. Cases with intrarectal or hidden rectal prolapse, a condition of lesser clinical importance, were excluded. The obstetric histories of the patients with rectal prolapse (n = 27) were compared to those of patients without rectal prolapse (n = 88). There was a larger proportion of nulliparous women in the rectal prolapse group than in the group without rectal prolapse, suggesting that factors in addition to parity play a role in the development of rectal prolapse. However, parous women with rectal prolapse had delivered significantly more children (3.3) than parous women without prolapse (2.5) (P = 0.03). The exact cause of rectal prolapse remains unclear. Childbearing appears to play a limited role in its pathogenesis since nulliparous women are also at risk of developing rectal prolapse. Received: 27 November 1997; Revision received: 15 April 1998; Accepted: 13 May 1998  相似文献   
949.
The purpose of our study was to evaluate the feasibility and accuracy of brain biopsies performed within a vertically opened MR system. We worked with the interventional 0.5-T MR “SIGNA SP” (General Electric Medical Systems, Milwaukee, Wis.) with an integrated tracking device “Flashpoint Position Encoder” (Image Guided Technologies, USA). As a holding device for this instrument we constructed a special frame. The whole system allows an exact adjustment of an optimum biopsy direction and guidance of the biopsy in a non-stereotactic, interactive mode in near real-time. As biopsy tools we used MR-compatible aspiration and specially made side-cut needles (Daum, Germany; E-Z-EM, USA). We performed a prospective diagnostic brain biopsy study in 18 patients. Guidance of the needle was carried out using gradient-echo single-slice technique. The sample was taken after controlling the exact position of the needle tip on spin-echo images. In 12 cases an exact neuropathological diagnosis was possible. In 6 cases of negative biopsy (4 aspiration biopsies) the samples were not representative. Our results demonstrate the feasibility of interactive MR-guided minimally invasive brain biopsies in an open MR system. The best results were achieved using cut needles for biopsies of contrast-enhancing lesions visible on T1-weighted gradient-echo guidance sequence. Received: 2 February 1998; Revision received: 13 July 1998; Accepted: 2 September 1998  相似文献   
950.
Accidental trauma frequently involves the extremities, and can extend to involve their blood supply, causing exsanguinating hemorrhage and pseudoaneurysm in the involved blood vessel. This is traditionally managed by surgical repair. We report a case in which control of life-threatening hemorrhage and exclusion of a large, post-traumatic pseudoaneurysm in the superficial femoral artery was performed by a commercially available stent-graft, without complication. This treatment method may be a safe and effective alternative to surgery in selected patients. Received: 10 February 1998; Revision received: 31 March 1998; Accepted: 20 April 1998  相似文献   
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