Cotte’s operation, PSN
Presacral neurectomy (PSN) is a surgical method for the treatment of severe chronic pelvic pain, most commonly caused by extensive endometriosis (the presence of uterine lining in abnormal localizations), and dysmenorrhea (painful menstruation). This procedure involves excision or interruption of the nerves coming from the pelvic organs, which carry pain signals upward into the brain.
The organs of the female reproductive system have sensory nerves that pass through the inferior hypogastric plexus (Pic. 1) to the spinal columns. If the so-called presacral nerve trunk is cut, the sensory signals are no longer conducted to the central nervous system. This causes denervation (loss of nervous function) of the uterus and a part of the urinary bladder. The desired effect of denervation is the reduction of pain conduction from the uterus to the spinal cord and the brain.
The nerve interruption or removal can be performed by open laparotomy, or, more commonly, by laparoscopic approach. The procedure is therefore nowadays commonly referred to as Laparoscopic presacral neurectomy (LPSN). Due to the proximity of the nerve trunk to major blood vessels, meticulous surgical technique is essential. The surgery is performed under general anaesthesia, and average hospital stay length after the procedure is two days.
Presacral neurectomy is a method of treatment for pelvic pain and dysmenorrhea (painful menstruation) which are resistant to previous treatment. The first-line method of treatment for dysmenorrhea and pain caused by endometriosis (Pic. 2) is laparoscopic excision. However, some women may continue to have symptoms even after the excision. This may be caused by deep infiltration of the uterine wall by endometriosis (called adenomyosis), which may in turn lead to increased uterine irritability and cramping. Presacral neurectomy may offer significant pain relief for these patients. It is also offered when medical therapy for pelvic pain has failed.
Less than 1% of all patients suffer from major complications following the surgery. They include constipation, which usually improves over time and with dietary modification. Some patients may experience urinary symptoms such as urgency (sudden, imperative need to urinate), which also tend to subside over time.
The efficacy of the procedure is reported to be up to 90%, but estimates vary. Most studies report an efficacy rate of 70 – 80% regarding pain relief.
The surgery does not affect the activity of the uterus during labor and does not have any effect on fertility. It may even cause the patient to experience painless labor, and therefore should be mentioned to the obstetrician.