What is the internal sphincter in regards to the male bladder, post prostatectomy incontinence and the external sphincter?” Hmmmmmmmmmm? If the internal sphincter is so important to continence then why don’t men leak after a TURP?
There was a comment about the internal sphincter and a patient being disappointed that the urologist did not tell him that it would be removed at the time of a prostatectomy. The patient has incontinence and is concerned that if the internal sphincter had not been removed he would not be leaking urine. Here are my thoughts and my understanding of continence after the prostate is removed..
- The external sphincter is a defined muscle that one can contract and stop and start the urinary stream.
- It is the primary sphincter for the control of continence after the prostate is removed.
- It is at the distal aspect of the prostate (furthest away from the bladder) and in normal circumstances is not disturbed by removing the prostate.
- It can be strengthened by doing Kegel maneuvers.
- The internal sphincter is not a well defined muscle but rather the confluence of muscles at the very tip of the bladder and blends into the urethra.
- The IS is responsible for antegrade ejaculation. It closes and propels the sperm forward.
- The IS, the prostate, and the external sphincter are all responsible for continence before a prostate is removed…only the external sphincter is available for continence after the prostate is removed.
- Often times if the dissection allows, the internal sphincter can be spared at the time of a prostatectomy (after removing the prostate the surgeon can see the bladder neck as a small opening that has tone and closes. The reason some surgeons might not want to try to preserve the bladder neck area is that there is the possibility that one leaves some prostate (not taking enough bladder neck above the prostate to assure that all the prostate and cancer are removed) in the area that abuts the bladder. In the original descriptions of Walsh nerve sparing prostatectomy surgeons purposefully took a wide area of the bladder neck so large that it would have be closed before reattaching the bladder to the urethra. This did not prove to be detrimental to continence.
- When urologists do a TURP we purposefully remove prostate tissue to open the prostatic urethra and trim the bladder neck area as well and in turn trim away the internal sphincter. A TURP rarely results in incontinence but almost always results in retrograde ejaculation.
- The fact that some men leak urine after the prostate has been removed has less to do with internal sphincter being removed than the surgical technique as it applies to the urethra and the external sphincter. As Walsh says, some men have a perfect surgery and still leak and this is something we don’t understand.
What do I tell people considering a prostatectomy? First of all I don’t always specifically mention the internal sphincter. I don’t think discussion of that is the critical point. I do however say this:
- The likelihood of leaking urine all the time is a real possibility but it occurs less than 1% of the time.
- Stress incontinence is common.
- It will take anywhere from 2 weeks to a year to reach your baseline continence level.
- It is not uncommon for patients not to leak at all after removal of the catether…but you can tell who will be which.
- The surgery could go badly and a patient not leak.
- The surgery could go very well and he leaks.
- If your primary concern is leaking urine…I’d recommend radiation. You will not have stress incontinence or total incontinence but you may very well have frequency or urgency incontinence.
Choose your poison.