Purpose: Published postoperative functional data have revealed insufficient nerve preparation for nerve sparing total prostatectomy. In this anatomical study we evaluated the distribution and quantity of periprostatic nerve tissue remaining on the nerve sparing aspect, which might aid in a more objective and accurate evaluation of postoperative function.
Materials and methods: A total of 47 whole mount serial sections of unilateral nerve sparing total prostatectomy specimens of 10 patients were stained with protein gene product 9.5 and evaluated. The extracapsular nerves were counted and classified into 2 primary groups, including greater than 200 and 200 mum or less. Mean values and percents of the nerve sparing aspects were compared to their corresponding nonnerve sparing side.
Results: Compared to the nonnerve sparing side 54% of nerves greater than 200 mum and 56% of those less than 200 mum remained on the nerve sparing side of the prostate. Only on the posterolateral aspect did significantly less nerve tissue remain vs that on the contralateral nonnerve sparing side (17% greater than 200 mum and 44% 200 mum or less, p = 0.01 and 0.09, respectively). Of the 3 prostate levels (base, mid and apex) the highest decrease in nerves greater than 200 and 200 mum or less was noted at the apex (28% and 39%), of which the posterolateral sector had the most effective nerve sparing (10% and 18%, respectively).
Conclusions: Common nerve sparing total prostatectomy provides the possibility to preserve around 55% of all periprostatic nerve fibers focused on the posterolateral location, especially at the apex (80% to 90% nerve sparing). However, it does not consider the actual course of the nerve fibers. To further improve the clinical outcome the actual nerve courses must be considered to preserve the nerve continuum. These findings suggest modification of the nerve sparing technique.