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We undertook this study to evaluate the mechanism of continence in women who underwent modified radical cystectomy and creation of an ileal neobladder. Our surgical technique was modified in accordance with detailed anatomic dissection of female pelvises with attention to the innervation of the pelvic musculature and urethral sphincter. Ten women aged 41-71 years (mean 64.3 years) underwent nerve-sparing radical cystectomy and creation of an orthotopic neobladder with detubularized ileum. Videourodynamic evaluation was performed 6 months postoperatively to evaluate sphincteric and reservoir function. Seven of the ten patients were totally continent after the procedure, requiring no protective pad. Of these, one requires intermittent self-catheterization. Videourodynamic evaluation revealed a low-pressure reservoir with a mean capacity of 467 ml, and leakage did not occur during Valsalva maneuver. Three patients reported significant incontinence (more than one pad per day) after orthotopic reconstruction. These patients demonstrated intrinsic sphincteric deficiency with a low mean abdominal leak-point pressure of 48.3 cmH2O. Two of these women had stress incontinence preoperatively. In conclusion, continence can be preserved in most women after modified radical cystectomy and orthotopic bladder replacement. Success results from preservation of the intrinsic sphincteric mechanism and the creation of a low-pressure, compliant reservoir. A history of stress incontinence preoperatively appears to predispose to sphincteric weakness postoperatively.

Purpose: A neuroanatomical study was initiated to gain better insight into the continence mechanism of the isolated urethra in women.Materials and Methods: We performed a detailed gross and histological neuroanatomical study to identify the intrapelvic somatic pathway from the sacral spinal cord to the female urethral sphincter. Gross anatomical dissection was performed in 5 formalin fixed female adult pelvises by tracing the autonomic nerves from the pelvic plexus and the spinal somatic nerves from S2-S4 to the urethral sphincter. Immunohistochemical staining of urethral step sections with a neuropeptide specific antibody was performed to demonstrate the course of the periurethral somatic nerves in relation to the vaginal wall.Results: Our study demonstrated an intrapelvic somatic pathway derived from the S2, S3 and S4 sacral roots, distinct from the peripheral pudendal nerve, supplying the levator ani and the urethra. The somatic nerves travel beneath the endopelvic fascia in close relation to t...

Image directed Doppler ultrasonography of the cavernous arteries provides functional, quantifiable assessment of penile arterial flow during a pharmacological erection. In this respect, this modality is superior to arteriography as a means of evaluating arteriogenic impotence. Peak flow velocity, arterial dilatation, and vessel pulsation are the most reliable ultrasonic indicators of arterial health. Aberrant arterial anatomy should be noted as this may contribute significantly to total penile blood flow. A thorough understanding of erectile physiology and anatomy is necessary to properly perform and interpret Doppler ultrasound results.

Erectile dysfunction is defined as the inability to achieve or maintain adequate penile erection (or both) for satisfactory intercourse.1 In the United States it is estimated that approximately 10 million to 18 million men suffer from erectile dysfunction.2 Penile erection is a complex phenomenon involving precisely timed neurologic and vascular responses. Although in the past erectile dysfunction has been attributed to psychogenic causes or explained as a normal part of the aging process, we now know that an organic etiology can be found to explain most cases of impotence. Organic impotence can be due to ȧ variety of causative factors including vascular, neurogenic, endocrinologic, and anatomic abnormalities. Vasculogenic impotence is likely the most common cause of organic impotence.3–6

We studied renal hemodynamic changes after complete acute unilateral ureteral obstruction in the young lamb.Seven 4-week-old lambs underwent unilateral complete ureteral obstruction and renal blood flow was monitored in both kidneys with ultrasonic flow transducers. Ureteral and arterial blood pressure was measured.In the obstructed kidney renal blood flow was stable for 5 hours and then decreased thereafter to 71% of baseline at 5 days (p0.05). In the contralateral kidney the pattern of renal blood flow constituted a mirror image, although the magnitude of the increase was decreased (122% of baseline at 5 days, not statistically significant). Mean arterial blood pressure did not change in 5 days. Mean ureteral pressure increased from a baseline of 9 to 37 mm. Hg (p0.001) 2 hours after obstruction but gradually decreased to 24 mm. Hg after 24 hours and remained elevated for 5 days (p0.001).The pattern of renal blood flow and ureteral pressure response to obstruction in the young lamb is different from that previously reported. Renal blood flow does not increase after obstruction and it is relatively preserved at 5 days. This unexpected response may be a result of the compound caliceal sheep kidney, immaturity of the young vascular system or development differences in the mechanism of spontaneous decompression of the collecting system.

The intrinsic urethral sphincter is composed of adjacent striated and smooth muscle. We studied the sequential expression of smooth and striated muscle proteins to gain insight into the ontogeny of intrinsic sphincter development.The intrinsic urethral sphincters of timed Fischer 344 rat embryos at 14, 16 and 18 days of gestation, neonates on postnatal day 1 and adult animals were examined. Serial sections of the urethra and adjacent levator ani muscles were studied histologically with hematoxylin and eosin, anti-alpha-smooth muscle actin, anti-alpha-sarcomeric actin and antistriated muscle myosin heavy chain antibodies.The intrinsic urethral sphincter was identified within the periurethral mesenchyma as early as day 14 of gestation. Although striated myotubules were identified within the urethra by hematoxylin and eosin staining starting on postnatal day 1, striated muscle myosin heavy chain protein was absent in the embryonic and neonatal development of the sphincter, and it was expressed only in the mature myotubule of adults. alpha-Smooth muscle actin was expressed throughout the urethral sphincter of embryonic and neonatal animals. In adults alpha-smooth muscle actin was confined to the smooth muscle component of the urethra. Co-expression of alpha-smooth and alpha-sarcomeric muscle actin by the striated sphincter myotubule was noted only in neonates.Development of the intrinsic urethral sphincter is characterized by sequential expression of well characterized muscle marker proteins. The co-expression of smooth and striated muscle markers by developing sphincter myotubule suggests the possibility that trans-differentiation of smooth to striated muscle occurs in the developing genitourinary tract.