I have been asked about the effectiveness of pre-sacral neurectomy (PSN) in providing pain relief and if it should be routinely performed as a part of endometriosis and pelvic pain surgery. For those of you not familiar with this term (PSN), it is a nerve cutting procedure done during laparoscopy in an attempt to decrease pelvic pain. This should not be confused with another similar procedure, Laparoscopic Uterosacral Nerve Ablation (LUNA) that has been shown in multiple studies to be ineffective and is not recommended.
PSN has been shown to be effective in relieving midline pelvic pain (pain only in the middle of the pelvis behind the pubic bone) but not pain on the sides (in the area wear the ovaries are located). In my experience, a patient’s pelvic pain resulting from endometriosis resolves after appropriate surgical removal and additional treatment is needed. PSN may be most useful in treating pain that is both in the midline and has been present since the first period, the medical term for this primary dysmenorrhea.
Pelvic pain is transmitted through not one or two nerves but many different nerves throughout the pelvis, which is one of the reasons it can be so difficult to treat. This is different than your pinky finger, which is innervated by only one nerve, the ulnar nerve. If a person had chronic pain in their pinky that did not respond to other treatments a nerve block of this nerve would relieve the pain. There is an area inside the body on the front side of the lower back called the superior hypogastric plexus that contains the major sensory nerves from the uterus and cervix but not the ovaries. This is the reason a PSN helps with pain coming from the uterus or cervix (midline) but not from the ovaries (lateral or on the sides).
There are surprisingly few studies on PSN. Information on the efficacy, or how well the PSN works, varies depending upon which scientific study is quoted. Most but not all studies show that when PSN is used in conjunction with other procedures to treat endometriosis or adhesion, about 75% to 80% experience a decrease in pain, especially painful periods (dysmenorrhea) while about 60% patients not receiving PSN as part of the pelvic pain surgery experience a decrease in their pain. Some studies have shown a decrease in painful sex (dyspareunia) following PSN while others have not shown a difference. This may be due to the multiple different causes of pain with intercourse, some of which may be helped with a PSN while others are not.
Most but not all studies show that when Pre-Sacral Neurectomy is used in conjunction with other procedures to treat endometriosis or adhesion, about 75% to 80% experience a decrease in pain, especially painful periods (dysmenorrhea) while about 60% patients not receiving PSN as part of the pelvic pain surgery experience a decrease in their pain.
But like any surgical procedure, PSN has potential risks and complications. The complications associated with this procedure include constipation, urinary urgency and decrease vaginal lubrication with sex, altered sensation bladder fullness. There is also a risk of damage to the ureters, bowel or blood vessels during surgery. The actual risk of developing these complications including constipation is not well documented in the scientific literature The few studies that we have reported a postoperative rate of constipation to be between 14% and 74% and about 5% of patients experiencing urinary urgency.
The possibility of chronic constipation as a result of PSN is most concerning. So many of my patients have a significant problem with constipation, to begin with that adding a procedure which can make this worse is of questionable benefit. A PSN is not reversible if it causes an unacceptable level of constipation. The approach and techniques I use to treat endometriosis and pelvic pain have a level approaching a 90% response rate (at least somewhat better) and thus I usually do not use PSN as an initial treatment. Patients who have always had killer periods from the very start or patients with pain as a result of significant adenomyosis (endometriosis in the muscle wall of the uterus) should consider PSN. Otherwise, I feel, PSN should be reserved for patients with midline pain that is unresponsive to conservative surgery. In conclusion, PSN seems to be effective in relieving midline pain, but with the potential for permanent side effects, conservative use for specific conditions is probably the best approach.
Two weeks ago, I had surgery to remove what an MRI indicated were ovarian cysts in my cul-de-sac. They went in and found that what was thought to be several large cysts, were actually hundreds of small clear cysts that look like drops of water.
My doctors have no idea what these are and do not think that I have Endo, but are stumped as to what it actually is. Lab says the cysts are not cancerous.
The cysts are on my peritoneum everywhere, not just the cul-de-sac. They removed hundreds from the cul-de-sac and removed my appendix, but left the rest of the cysts in place because they simply hadn’t be prepared to deal with such an extensive problem and it is better to deal with something when you know what it is. And they think that even if they took them all out, the cysts would just come back.
That aside, I’m still in a large amount of pain. I had considered asking my doctor about cutting nerves so that if I do have endo, I don’t have to live my life in crushing pain. Since this started months ago, I’ve stopped living so many aspects of my life. Having read your article, I think I’ll wait on cutting nerves because of the potential side effects.
But I do have a question. 6 years ago I had real ovarian cysts removed and after the surgery, my skin between my belly button and pelvis,… lost the ability to sense that it was being touched and heat and cold. I was told that this meant that some nerves had been cut and they would regrow. Feeling did come back, but not to the same extent it existed before. With this second surgery, feeling is gone again.
But my question is… will the nerves cut in PSN eventually grow back?
Yes they do. However it DID help me. I have had 8 surgeries for endo & was finally blessed with a child – miracle – 17 months ago – 2yrs after my last surgery.
Nerves always grow back – sometimes it is months, sometimes years.
I wish you luck!
I had a PSN when I was 20 and it saved my life. I was suicidal because of the pain and was then blessed to find an amazing doctor who listened to me. I went from taking narcotics almost every day to taking midol at most. It has been about 61/2 years since the procedure and I am slowing getting some pain back but it is manageable. I wish this information is more available to young girls b/c so many of them are giving up and being advised that a hysterectomy is their only options. It makes me angry and breaks my heart at the same time.