Login to Access Video or Poster Abstract: MP40-18
Sources of Funding: nond

Introduction

To histologically investigate the female fibromuscular construction and nerve distribution around the posterior and lateral regions of the vesicourethral junction. These findings will help improve the functional results seen after nerve-sparing radical cystectomy and clarify differences in elderly female cadavers, especially with regard to pelvic organ prolapse (POP).

Methods

Histological examination of 22 female cadavers with subsequent evaluation of immunohistochemistry was performed. Macroslices of 1) urethra, 2) anterior wall of the vagina and 3) inferomedial edge of the levator ani muscle was performed. Elastica Masson staining and immunohistochemical staining [anti-S100 protein, anti-neuronal nitric oxide synthase (nNOS), anti-vasoactive polypeptide (VIP), anti-tyrosine hydroxylase (TH), and anti-alpha smooth muscle actin (SMA)] was performed.

Results

The bladder detrusor merged with the vaginal wall smooth muscles in the posterior side of the urethra. Anterior and lateral parts of bladder detrusor were clearly separated from the urethral wall smooth muscles in the medial side of the upper reflection of the endopelvic fascia from the levator ani muscle to the external surface of the bladder. In 8 of the 22 cadavers, smooth muscle mass occupied in a space between the urethra and the inferomedial edge of the levator ani muscle and covered the inferior margin of the detrusor muscle. The rhabdosphincter was seen far inferior to the inferomedial edge of the levator. The endopelvic fascia contained abundant nerves coming from the pelvic plexus. The detrusor nerves entered the bladder and candidates of the cavernous and sphincter nerves ran inferomedially from the endopelvic fascia.

Conclusions

Smooth muscles and collagen fibers were found at the posterolateral corner of the vesicourethral junction in one-third of the cadavers (HSM). Autonomic nerve fibers innervating cavernous tissue and sphincter muscles run between the HSM and the urethra. There were variations in the ventrodorsal relationship between CSNs and DNs between cadavers. We report the first histological demonstration of nerves that innervate urethral sphincter in adult women.

Funding

nond