Anatomical and electrophysiological assessment of the canine periprostatic neurovascular anatomy: perspectives as a nerve sparing radical prostatectomy model.

PURPOSE

Although the dog is often used as a radical prostatectomy model, precise descriptions of canine prostate and neurovascular bundle anatomy are lacking. We describe canine prostate and neurovascular bundle anatomical and electrophysiological characteristics.

MATERIALS AND METHODS

The canine prostate and pelvic neurovascular structures were dissected in 6 canine cadavers and 12 anesthetized dogs. Pelvic plexus branches were stimulated using a CaverMap probe and peak intracavernous pressure responses were recorded as a percent of mean arterial pressure.

RESULTS

The canine pelvic plexus lies 5 to 10 mm lateral to the prostate. It is supplied by the hypogastric nerve cranially and the pelvic nerve laterally. The neurovascular bundles course distal from the pelvic plexus along the posterolateral aspect of the prostate, including a dominant cavernous nerve along its lateral aspect. CaverMap stimulation of the efferent branches of the pelvic plexus confirmed their roles in tumescence. Histology revealed extensive neurovascular tissue along the posterolateral aspect of the prostate beneath the periprostatic fascia. Notable differences to human anatomy were the absence of seminal vesicles, the lateral positions of the pelvic plexus, the dominant cavernous nerve and the circumferential urethral distribution of the cavernous nerves.

CONCLUSIONS

Canine neurovascular anatomy resembles that of humans and it is a suitable model in which to assess prostatectomy related erectile dysfunction. However, there are key differences in neurovascular relationships that must be considered when the canine prostate is used as a radical prostatectomy model.