Читать книгу Saving Your Sex Life: A Guide for Men With Prostate Cancer - John P. Mulhall - Страница 8

I previously mentioned the dorsal nerves of the penis, which are purely sensory. However, erection nerves are entirely different. While the sensory nerves travel with the erection artery underneath the ischiopubic ramus, the erection nerves travel very much like the accessory pudendal arteries I mentioned earlier alongside the prostate. Many men equate penis sensation or even orgasm with erection nerve function. In fact, the erection nerves can be completely damaged and sensation will be unaffected.

The complex neuro-anatomy was only first described in great detail for surgeons in the early 1980s, and this is how Dr. Patrick Walsh at Johns Hopkins Medical Institutions first developed the nerve sparing (also known as the anatomical) prostatectomy. Prior to 1982, all prostatectomies were conducted with little attention paid to the erection nerves. These erection nerves, known as the cavernosal nerves (also known as the cavernous nerves), start their journey from the spinal cord. They start at the lowest portion of the spinal cord known as the sacral area, and then travel out of the spinal cord and the vertebral column to join a plexus of nerves. Think of an old telephone switchboard with numerous wires traveling in multiple directions, and this best describes a pelvic nerve plexus. From this pelvic nerve plexus sitting along the front of the rectum, they travel forward alongside the prostate, pass under the pubic bone into the penis to supply the erection tissue that I previously described. While the nerve anatomy is somewhat variable, it is well accepted that the major fibers travel in intimate contact with the prostate.

The simplest way to think of it is if you imagine an orange that represents the prostate, covered on its top half with Saran Wrap. Inside the Saran Wrap layer are the cavernous erection nerves. Thus, during dissection and removal of the prostate, one can easily see how these nerves can be injured. Even in the hands of a highly experienced and skilled surgeon who does excellent nerve sparing, when these nerves are handled, their response is to go to sleep.This dormancy period can last 12 to 24 months.This is why men after radical prostatectomy often have a highly delayed recovery of erectile function.These nerves supply the smooth muscle in the penis,and they supply this tissue with nitric oxide, which is the main factor that causes the smooth muscle to relax, allowing the lacunar spaces to expand and fill with blood. During radiation therapy for prostate cancer, the nerves are in the field of radiation as they are in close contact with the prostate; radiation is usually delivered not just to the prostate but also to a margin of about 1cm around the prostate.