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Ohne ZusammenfassungNach einem Vortrag gehalten in der Universität.  相似文献   
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PURPOSE: To find a suitable high-resolution MR protocol for the visualization of lesions of all 12 cranial nerves. MATERIAL AND METHODS: Thirty-eight pathologically changed cranial nerves (17 patients) were studied with MR imaging at 1.5 T using 3D T2*-weighted CISS, T1-weighted 3D MP-RAGE (without and with i.v. contrast medium), T2-weighted 3D TSE, T2-weighted 2D TSE and T1-weighted fat saturation 2D TSE sequences. Visibility of the 38 lesions of the 12 cranial nerves in each sequence was evaluated by consensus of two radiologists using an evaluation scale from 1 (excellently visible) to 4 (not visible). RESULTS: The 3D CISS sequence provided the best resolution of the cranial nerves and their lesions when surrounded by CSF. In nerves which were not surrounded by CSF, the 2D T1-weighted contrast-enhanced fat suppression technique was the best sequence. CONCLUSIONS: A combination of 3D CISS, the 2D T1-weighted fat suppressed sequence and a 3D contrast-enhanced MP-RAGE proved to be the most useful sequence to visualize all lesions of the cranial nerves. For the determination of enhancement, an additional 3D MP-RAGE sequence without contrast medium is required. This sequence is also very sensitive for the detection of hemorrhage.  相似文献   
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Stent placement is a widely used bail-out treatment for dissection of peripheral arteries. Below the level of the superficial femoral artery permanent stenting is complicated by a high incidence of subacute thrombosis and restenosis. We present two cases of arterial occlusion due to acute iatrogenic dissection of the popliteal and distal fibular arteries. Successful treatment was achieved with a new bail-out procedure. Strecker stents were implanted to seal off the dissection flap. Stents were retrieved easily after 24 hr using a myocardial biopsy forceps. After stent retrieval the temporarily stented segments were patent and showed a larger lumen compared with segments treated by balloon dilatation alone. Temporary stenting is a simple and safe procedure and offers the advantage of tacking up dissection membranes and preventing recoil. Persistent presence of a metallic implant as a source of continued injury and stimulus for intimal proliferation is avoided.  相似文献   
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PURPOSE: We prospectively evaluate the safety, morbidity and complication rates for first and repeat transrectal ultrasound guided prostate needle biopsies. MATERIALS AND METHODS: In this prospective European Prostate Cancer Detection Study 1,051 men, with total prostate specific antigen between 4 and 10 ng./ml., underwent transrectal ultrasound guided sextant biopsy plus 2 additional transition zone biopsies. Biopsy samples were also obtained from suspicious areas identified during transrectal ultrasound and digital rectal examination. All 820 patients with biopsy samples negative for prostate cancer underwent re-biopsy after 6 weeks. Immediate and delayed (range 1 to 7 days) morbidity, patient satisfaction and complication rates were recorded. RESULTS: Of the 1,051 subjects the initial biopsy was positive for prostate cancer in 231 and negative, including benign prostatic hyperplasia or benign tissue, in 820. Of these 820 patients prostate cancer was detected in 10% (83) on re-biopsy. Minor or no discomfort was observed in 92% and 89% of patients at first and re-biopsy, respectively (p = 0.29). Immediate morbidity was minor and included rectal bleeding (2.1% versus 2.4%, p = 0.13), mild hematuria (62% versus 57%, p = 0.06), severe hematuria (0.7% versus 0.5%, p = 0.09) and moderate to severe vasovagal episodes (2.8% versus 1.4%, respectively, p = 0.03). Delayed morbidity of first and re-biopsy was comprised of fever (2.9% versus 2.3%, p = 0.08), hematospermia (9.8% versus 10.2%, p = 0.1), recurrent mild hematuria (15.9% versus 16.6%, p = 0.06), persistent dysuria (7.2% versus 6.8%, p = 0.12) and urinary tract infection (10.9% versus 11.3%, respectively, p = 0.07). Major complications were rare and included urosepsis (0.1% versus 0%) and rectal bleeding that required intervention (0% versus 0.1%, respectively). Furthermore, an age dependent pattern of pain apprehension during biopsy was observed with the highest scores in patients younger than 60 years. CONCLUSIONS: Transrectal ultrasound guided biopsy is generally well tolerated with minor morbidity only rarely requiring treatment. Re-biopsy can be performed 6 weeks later with no significant difference in pain or morbidity. Patients younger than 60 years should be counseled in regard to a higher level of discomfort, and local and topical anesthesia if desired.  相似文献   
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The diagnostic work-up of lower urinary tract symptoms (LUTS) in the German guidelines consists of obligatory and optional diagnostic parameters. Recommendations for assessing LUTS include patient history, symptom questionnaires (IPSS international prostate symptoms score), physical examination, urine analysis, prostate-specific antigen, uroflowmetry, ultrasound examination of the urinary bladder, including postvoid residual urine and ultrasound examination of the upper urinary tract. Optional tests are voiding diary, pressure-flow studies, ultrasound measurement of detrusor wall thickness, urethrocystography and urethrocystoscopy. Ultrasound measurement of detrusor wall thickness in particular has a 95 % positive predictive value in diagnosing bladder outlet obstruction. With all diagnostic parameters it is possible to treat LUTS in a risk-adapted manner.  相似文献   
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