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81.
Stenosis of the hypopharyngo-oesophageal junction can be a rare complication of laryngectomy and/or partial pharyngectomy and makes the insertion of voice prosthesis extremely difficult. This study describes the authors’ experiences gained by endoscopic balloon-catheter dilatation of hypopharyngo-oesophageal stenoses prior to implantation of voice prostheses in four cases. In two patients a single balloon-catheter dilatation resulted in wide enough pharyngo-oesophageal lumen on the long run. The average prosthesis wearing-times were 6.8 months in case 1 and 4.6 months in case 2, corresponding to the published literature data. In case 3, repeated dilatation of the pharyngo-oesophageal transition had proved to be unsuccessful despite taking every effort with the endoscopic balloon-catheter method. Having excised the stenotic segment, reconstruction with pectoralis major myocutaneous flap (PMMF) was indicated. Eighteen months later, a repeated restenosis was observed and a free jejunal flap needed to be performed as a final solution. In case 4, the insertion was carried out into a previously dilated jejunal free flap, which became gradually ischemic and stenotic since the major head-and neck procedure was carried out that resulted in prosthesis rejection after just 1 week. The authors emphasize that correct indication of pedicled and free flaps in head and neck reconstruction is a prerequisite from the aspect of prevention of pharyngo-oesophageal strictures. Endoscopic balloon-catheter dilatation is a safe and established method for dilatating hypopharyngo-oesophageal stenoses of different origin. The procedure provides maximum patient benefit with minimal trauma and morbidity; moreover, facilitates insertion of voice prostheses. However, a single balloon-catheter dilatation cannot always result in wide enough oesophageal lumen on the long run (case 3). Insertion of a voice prosthesis into a previously dilated ischemic jejunal segment is challenging and avoidable due to risks of complications.  相似文献   
82.
Epiploic appendagitis and omental infarction: pitfalls and look-alikes   总被引:3,自引:0,他引:3  
Epiploic appendagitis and omental infarction are benign self-limiting conditions that are more frequent than generally assumed. Both disorders frequently mimic symptoms of an abdominal surgical emergency, often leading to clinical misdiagnosis of appendicitis or diverticulitis. Because a misdiagnosis can result in an unnecessary laparotomy, a correct diagnosis is of great importance. Ultrasound and computed tomography can be used to make a reliable diagnosis. This pictorial essay illustrates the various ultrasonographic and computed tomographic appearances of epiploic appendagitis and omental infarction and focuses on their radiologic differential diagnoses and pitfalls. Received: 22 February 2001/Accepted: 18 April 2001  相似文献   
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Ohne Zusammenfassung  相似文献   
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During the past few decades, management of patients with myocardial infarction has dramatically evolved. High-risk patients are now identified by a variety of noninvasive tests, and aggressive use of reperfusion strategies has improved clinical outcomes. Despite the benefits of reperfusion, only a few patients are eligible to receive thrombolytic therapy. Mortality rates among patients excluded from thrombolytic trials (15% to 20%) have been far greater than those eligible for treatment (3% to 10%). Because most deaths occur within the first few days of infarction, interventions designed to reduce mortality should be performed acutely. Immediate catheterization allows identification of high-risk anatomy that may benefit from surgery and allows coronary angioplasty to be performed as a reperfusion strategy (when appropriate). Furthermore, catheterization allows documentation of ejection fraction, vessel patency, number of diseased vessels, and residual stenosis, all of which have been predictive of prognosis. Conversely, frequently repeated noninvasive diagnostic tests are associated with increased cost, are generally performed in low-risk patients, and 60% to 80% of patients with myocardial infarction ultimately require catheterization anyway. It is possible that early catheterization and percutaneous transluminal coronary angioplasty when indicated may effectively risk stratify patients (eliminating the need for noninvasive testing), may reduce morbidity and mortality, and shorten the length of hospital stay.  相似文献   
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In the gerbil maintained at euthermic (37.5 degrees C) conditions, forward masking produces a compound action potential tuning curve (CAP TC) which is less sensitive but more sharply tuned than that which is generated by simultaneous masking. These differences between forward- and simultaneously-masked CAP TCs are minimized at hypothermic (30 degrees C) conditions. The unmasking effect occurs at both temperatures, suggesting that hypothermia does not exert these changes by eliminating two-tone suppression.  相似文献   
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