The Effect of Temporary Ovarian Suspension to the Abdominal Wall During Laparoscopic Endometriosis Surgery for Adhesion Prevention -A Comparative and Prospective Study

Endometriosis is a chronic condition characterized by growth of endometrial tissue in sites other than the uterine cavity, most commonly in the pelvic cavity, including the ovaries, the uterosacral ligaments, and the pouch of Douglas. Laparoscopic excision of endometriosis lesions has become the gold standard treatment. At follow-up, relief of pain and quality of life after endometriosis surgical treatment ranges between 50% and 95%. However, pelvic surgery for endometriosis has been associated with a high rate of postoperative adhesion formation. The incidence of pelvic adhesions at second-look laparoscopy in the initial few weeks after surgery has been reported to be between 50% and 100%. The ovaries are the most common site involved by adhesions because of their anatomic localization (close to the pelvic sidewall and the homolateral tube) and the fragility of the coelomic epithelium that covers the ovarian surface \[7,8\]. In addition, when the posterior pelvic compartment is involved, obliteration of the pouch of Douglas is often observed as a result of a post-inflammatory process causing ovarian adhesions \[9\]. Women with higher risk for postoperative ovarian adhesions include those who have preoperative ovarian adhesions or patients undergoing ovarian cystectomy, peritonectomy of the ovarian fossa or extensive pelvic adhesiolysis. Postoperative retained free fluid with blood and postoperative infections may also increase the risk for adhesions. Postoperative adhesions are a source of major concern because of their potential consequences including persistent pelvic pain, dyspareunia (difficult or painful sexual intercourse), infertility, intestinal obstruction, and complications at subsequent surgery.

A wide range of interventions has been tried in the past in order to reduce postoperative pelvic adhesions. This includes intra-peritoneal administration of anti-adhesive solutions such as icodextrin and hyaluronic acid. Various drugs including steroids and heparin have also been tried in the past but none of them have gained wide acceptance (Metwally et al., 2006; Kamel, 2010). Oxidized regenerated cellulose was found to reduce postoperative adhesion in two very small RCTs (Ahmad et al., 2008).

Intra-operative suspension of the ovaries to the anterior abdominal wall is sometimes used to facilitate ovarian retraction and improve exposure of the pelvis during surgery for severe endometriosis (Cutner et al., 2004). Temporary ovarian suspension can be achieved using a straight needle and absorbable suture to suspend the ovary to the abdominal wall with an external knot tie that can be easily removed at any time after surgery. Two small observational studies suggested that temporary ovarian suspension for 4-7 days following surgery for severe endometriosis may reduce the frequency of postoperative pelvic adhesions (Abuzeid et al., 2002; Ouahba et al., 2004).

The Objective of the Study The primary objective of the study is to examine adhesion formation following laparoscopic surgery with temporary ovarian suspension removed a week after surgery.

The secondary objective is the analyze patient symptoms and adherence to the ovarian suspension as well as request to remove the suture before one week post operative.

Rationale for conducting the study If ovarian suspension is indeed beneficial it can be incorporated as part of common practice for laparoscopic endometriosis surgery.

Methods This is a prospective single-blinded randomized controlled interventional study.

Patients scheduled for laparoscopic surgery due to endometriosis with suspected adnexal adhesions, lesions of the ovary, ovarian fossa, uterosacral ligaments, pouch of Douglas, or involvement of the bowel, as seen by imaging, will be included. A comparison will be made between suspended ovaries in the study group vs. non-suspended ovaries in the control group. During surgery, the primary surgeon will inspect the pelvis. If on the side of the relevant ovary there are adhesions and/or ovarian cyst and/or peritoneal lesions around the ovarian fossa and uterosacral ligament, an ovarian suspension will be performed according to randomization. The randomization process will be based on a preformed list produced by the statistician which will be used during surgery. In case of bilateral pelvic involvement, the left ovary will be the first to be acted on according to the randomization result (i.e suspend/not suspend). In case of ovarian cysts, the surgeon will decide upon treatment method of the cyst during surgery. Suspension of the ovary will be performed using Monocryl absorbable suture. In order to reduce confounding variables, there will be no use of anti-adhesive barriers. Removal of the suspension will be performed at the clinic a week after surgery unless the patient requests to remove the suture earlier. Patients will be asked to fill a daily questionnaire describing the amount of pain according to VAS score they are experiencing due to ovarian suspension and how eager they are to remove the suture prematurely on a scale of 1-10.

Preoperative and postoperative ultrasound evaluation will be performed by one of two dedicated ultrasound experts using a Voluson E10 ultrasound. During postoperative evaluation, the experts will be blinded as to whether ovarian suspension was performed or not. Postoperative ultrasound will be performed 6 and 13 weeks following surgery and will include description of the size of the ovary, location and severity of adhesions.

Statistical analysis will be performed according to each suspended vs non-suspended ovary, i.e. the number of ovaries suspended for the study group vs, the number of non-suspended ovaries in the control group patients.

• Patient pain during the first week following laparoscopy [Time frame: From enrollment to 1 week post-operative follow-up visit]
• Patient tolerability to ovarian suspension during the first week following surgery [Time frame: From enrollment to 1 week post-operative follow-up visit]