Neuroanatomy of the ureterovesical junction: clinical implications.

Abstract

The anatomy of the ureterovesical junction is germane to surgical reconstruction in patients with significant reflux. In this study we refine the description of the neuroanatomy of the distal ureter and ureterovesical junction. The distal ureter and bladder including the ureterovesical junction from 6 normal human fetuses (3 female and 3 male) at 21 to 40 weeks of gestation were studied using immunohistochemical analysis and 3-dimensional imaging techniques with antibodies against the nonspecific neuronal markers S-100 and nitric oxide synthase (nNOS). Nerves were observed to occupy the medial aspect of the distal ureter. At the ureterovesical junction the nerves encircled the entire ureter. They traveled just outside Waldeyer's sheath, leaving a safe area for surgical dissection under the sheath. As the ureter tunneled into the bladder, the nerves localized to the lateral wall of detrusor muscle. The nerves originating from the ureter and bladder and innervating the trigonal area were immunoreactive to S-100 and nNOS. nNOS positive nerve fibers arising from the bladder and ureteral nerves were found spreading among the detrusor fibers in the trigonal area. A detailed knowledge of the distal ureteral and ureterovesical junction neuroanatomy and the pathway of these nerves in relation to the anatomical landmarks is critical for preserving bladder function. Based on these anatomical dissections, we would recommend careful dissection within Waldeyer's sheath during ureteral reconstructive surgery.