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PURPOSE: We refined recently developed pressure flow cutoff values for female bladder outlet obstruction and applied these values in a consecutive group of women undergoing urodynamic testing for various lower urinary tract symptoms. MATERIALS AND METHODS: A total of 87 women with clinical obstruction determined by history and presenting complaint were enrolled in our prospective evaluation of pressure flow studies. We identified 3 groups of participants according to the suspected cause of obstruction, including prolapse in 33, previous incontinence surgery in 25, and no likely source of obstruction identified from history and physical examination only in 29. An additional 124 patients presenting for evaluation of stress urinary incontinence served as controls. Optimal cutoff values for determining obstruction were developed using receiver operating characteristic curves. To determine the prevalence of bladder outlet obstruction these values were prospectively applied to 106 women undergoing urodynamics for various voiding complaints. RESULTS: In controls the average maximum flow rate was 23 cc per second and average detrusor pressure was 21.9 cm. water, whereas the corresponding values in those with clinical obstruction were 10.7 cc per second and 40.8 cm. water (p <0.001). No differences were noted in the various obstruction groups. Receiver operating characteristics analysis revealed that cutoff values of 11 cc per second or less and 21 cm. water or more optimized the selection of patients with bladder outlet obstruction. Using these values we noted a bladder outlet obstruction prevalence of 20% in a consecutive cohort of women undergoing urodynamic studies at our center. CONCLUSIONS: We propose cutoff pressure flow values for identifying women with bladder outlet obstruction although they should be used only in conjunction with the overall clinical situation. Neither pressure flow data only nor clinical symptoms alone may be sufficient for diagnosing obstruction in women.  相似文献   
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Hypospadias and urethral development   总被引:16,自引:0,他引:16  
PURPOSE: Hypospadias is a common congenital anomaly that may be treated with surgical reconstruction. In the majority of cases the etiology remains elusive. Although androgens are clearly critical for penile development, defects in androgen metabolism and/or the androgen receptor explain only a small subset of cases of hypospadias. Strategies are presented for understanding the etiology of hypospadias. MATERIALS AND METHODS: Current scientific reports on the etiology of hypospadias were reviewed, and the embryology and possible mechanisms of urethral and penile formation are presented. RESULTS: A new theory of glandular human urethral development via endodermal cellular differentiation is proposed to replace the classic explanation of ectodermal intrusion. CONCLUSIONS: Careful studies of penile and urethral development have led to a better understanding of genital embryology. Future areas of study, such as endocrine disrupters, mesenchymal-epithelial interactions and mechanisms of penile growth, are proposed to explain the etiology of hypospadias.  相似文献   
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PURPOSE: We analyze a group of patients who presented with mechanical dysfunction of the reservoir and/or efferent limb of a continent colonic urinary diversion, and establish an evaluation and management algorithm. MATERIALS AND METHODS: A total of 16 patients with a mean age of 58 years and 1 or more symptoms related to continent colonic urinary diversion were evaluated. Presenting symptomatology included difficult catheterization in 8 cases (50%), disabling incontinence in 8 (50%) and recurrent urinary tract infections in 6 (37.5%). All patients had normal, nonobstructed, nonrefluxing upper tracts and none presented with stone disease. Urological evaluation consisted of catheterization, fluoroscopy and urography of the pouch, retrograde urography of the external limb and urodynamics (enterocystometrogram and outlet pressure profilometry). RESULTS: Of the 8 patients with difficulty with catheterization 4 had stomal stenosis, 2 had an elongated and redundant external limb, and 2 had a false passage. Diagnosis was established by the inability to catheterize, fluoroscopy of the pouch and retrograde urography. Disabling incontinence occurred in 8 patients, including 7 who presented with an incompetent outlet and 2 with high pressure intestinal contractions of the reservoir. The aforementioned abnormalities were diagnosed by a combination of retrograde urography, urography of the pouch and urodynamics. Recurrent symptomatic urinary infections were observed in 5 patients of the previous groups and in another with an hourglass reservoir, which was primarily diagnosed by urography of the pouch. Surgical correction in 15 patients included outlet reinforcement, reservoir revision, stomal or external limb revision and conversion to a urinary conduit. Surgical treatment was successful in 14 of 15 patients (93%). CONCLUSIONS: Catheterization difficulty requires retrograde urography to define possible anatomical abnormalities (false passage, conduit elongation) if catheterization and fluoroscopy of the pouch do not demonstrate stomal stenosis. Urinary incontinence benefits from enterocystometry and outlet pressure measurement to determine reservoir and external limb function. Recurrent urinary tract infections not related to ureteral obstruction or reflux requires fluoroscopy of the pouch and external limb to determine abnormalities in patients with detubularization and localization of areas of urine pooling.  相似文献   
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PURPOSE: We performed a prospective study to determine the incidence and spectrum of metabolic abnormalities predisposing to stone formation in patients with ureteropelvic junction obstruction and renal calculi. MATERIALS AND METHODS: A total of 47 consecutive patients with congenital ureteropelvic junction obstruction underwent metabolic evaluation of stone risk factors. Of these patients 21 had associated stones (study group), while 26 did not (control group). Logistical regression, Wilcoxon rank sum and Fisher's exact tests were performed to determine whether there was a significant difference between these groups in regard to the presence of metabolic risk factors. RESULTS: Demographically and symptomatically the 2 groups were equivalent except that the study patients were older. The 24-hour urinary excretion of calcium was significantly higher in study than in the control patients (p = 0.007). While the incidence of hypercalciuria and hyperuricosuria was also higher in the study population, these differences were not significant (p = 0.08 and 0.07, respectively). CONCLUSIONS: Metabolic abnormalities predisposing to stone formation are present more frequently in patients with ureteropelvic junction obstruction who have associated stones compared to those who do not. As such, urinary stasis alone does not explain stone formation in these cases. Rather, the local physiological environment of urine likely has a predisposing role. In addition to restoring unobstructed urinary flow, consideration should be given to metabolic evaluation and prophylactic treatment for affected patients.  相似文献   
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目的:利用彩色多普勒超声筛查孕中晚期胎儿异常或畸形,降低围产死亡率,提高人口出生质量。方法:对我院2002年1月至2005年3月1980例孕中晚期胎儿彩色多普勒超声检查结果回顾性分析。结果:检出胎儿畸形45例,死胎12例,低置胎盘24例,38周~42周胎位不正51例、脐绕颈316例。其中绝大多数在本院或外院引产证实,少数经过尸解证实。结论:彩色多普勒超声可发现大多数的胎儿形态结构异常,使一些致死性的畸形及早终止妊娠,非致死性的异常或畸形有了选择的空间;在提高人的出生质量上彩色多普勒超声起着不可或缺的作用,而且越来越显现出其独特的功能所在。  相似文献   
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