Beco J, Sulu M, Schaaps J P, Lambotte R
Département de Gynécologie et d'Obstétrique, Université de Liège, Belgique.
J Gynecol Obstet Biol Reprod (Paris). 1987;16(8):987-98.
The vesicourethral junction, the urethra cannot be seen when using the abdominal approach because of the interposition of the pubic symphysis. The ultrasonic vaginal approach makes it possible. 53 patients were ultrasonically observed during an urodynamic exploration. The simultaneous utilization of both methods has permit to observe the mechanisms of normal or pathological voiding. When initiating a voluntary micturition, an area (called "prepubic muscle") located in front of the pubic symphysis between the clitoris and the urethral meatus, exert a traction on the periurethral sphincteric area. This sphincteric area, which is well shown by ultrasound, contracts longitudinally (causing shortening of the urethra and opening of the bladder neck) and causes a drop in urethral closure pressure. The increase in the distance between the inferior part of the pubic symphysis and the anterior vaginal wall comes about because of slackening of the elevator ani muscles. This slackening occurs at different times before the bladder contracts. The urethra opens; the complete course of this organ is well defined. Things return to their previous state when voiding finishes. In the case of stress incontinence, the lack of transmission of pressure urodynamically found when the woman is coughing can be seen as a sliding mechanism within the space of Retzius and at the urethro-vesical junction behind the symphysis pubis. The degree of sliding depends on the strength of the cough. In all cases of pure stress incontinence without there being low urethral closure pressure, a maximum stress caused by coughing will produce more than 5 MM sliding before the urethra opens. If the urinary incontinence is due to low urethral closure pressure, the urethra opens without sliding of the urethro-vesical junction whenever the abdominal pressure increases. Urethral instability resembles voluntary voiding but without any voluntary command. "Prepubic" contractions, longitudinal contractions in the sphincteric area and slackening of the levator ani muscles, alone or in association, explain why urethral closure pressure drops. Sometimes this drop is followed by an increase in bladder pressure.
膀胱尿道连接部，采用腹部入路时由于耻骨联合的阻挡无法看到尿道。而超声阴道入路则可以做到。在尿动力学检查过程中对53例患者进行了超声观察。两种方法同时使用有助于观察正常或病理性排尿的机制。当开始自主排尿时，位于耻骨联合前方、阴蒂与尿道口之间的一个区域（称为“耻骨前肌”）会对尿道周围括约肌区域施加牵引力。超声能很好地显示这个括约肌区域，它纵向收缩（导致尿道缩短和膀胱颈开放）并引起尿道闭合压下降。耻骨联合下部与阴道前壁之间距离的增加是由于肛提肌松弛所致。这种松弛在膀胱收缩前的不同时间发生。尿道开放；该器官的完整行程清晰可见。排尿结束后一切恢复到先前状态。在压力性尿失禁的情况下，女性咳嗽时尿动力学检查发现的压力传递缺失可被视为耻骨后间隙及耻骨联合后方尿道膀胱交界处的滑动机制。滑动程度取决于咳嗽的力度。在所有无尿道闭合压低的单纯压力性尿失禁病例中，咳嗽引起的最大压力会在尿道开放前产生超过5毫米的滑动。如果尿失禁是由于尿道闭合压低引起的，每当腹压增加时尿道就会开放而尿道膀胱交界处无滑动。尿道不稳定类似于自主排尿，但没有任何自主指令。“耻骨前”收缩、括约肌区域的纵向收缩以及肛提肌的松弛，单独或联合起来，解释了尿道闭合压下降的原因。有时这种下降之后会伴有膀胱压力升高。
