Endometriosis

This is a pathological condition in which tissue resembling the normal lining of the cavity of the uterus (endometrium) is found outside the cavity of the uterus. It may occur in and on any of the reproductive organs as well as the pelvic cavity (lining) and organs in the pelvic cavity. Depending on the degree of endometriosis it can be associated with an increased risk of infertility, abdominal pain during menstruation and pain during sexual intercourse. Endometriosis can be successfully treated with surgery.

Laparoscopic diagnosis of endometriosis

A noninvasive method of diagnosing endometriosis is not currently available. The diagnosis of endometriosis is achieved through visual or histopathological documentation, the least invasive method of which is laparoscopic surgery. The magnification offered by the laparoscope may also aid in the diagnosis of endometriosis.

In the pelvis, three different forms of endometriosis must be considered:

• peritoneal
• ovarian
• rectovaginal

The appearance of peritoneal endometriosis is quite diverse, ranging from very subtle alterations, which are difficult to be grossly visualised, to typical black, puckered powderburn lesions. Endometriosis can also be represented by white opacified changes and, most commonly (81%), by red flame-like lesions.

Nonpigmented endometriotic peritoneal lesions include the following:

• white opacified lesions indicating scarring which may be raised or thickened;
• red flame-like lesions which may be elevated;
• glandular lesions which can contain endometriosis in 67% of cases; glandular lesions have the same gross appearance as normal endometrium (eg at hysteroscopy);
• subovarian adhesions that resemble infectious aetiology;
• yellow-brown peritoneal patches;
• circular peritoneal defects which are due to endometriosis in more than 50% of cases;
• areas of petechial peritoneum or areas with hypervascularisation.

Subtle or atypical lesions probably represent a more active form of endometriosis. With increasing age, there is a progression to the less active 'typical' form of endometriosis. A combination of laparoscopy, palpation with the blunt probe, and intraoperative rectovaginal examination may be needed to make the diagnosis. The ability to diagnose atypical and subtle appearances of endometriosis is directly related to the experience and skill of the surgeon.

To further complicate the diagnosis, histological examination of biopsies from visually normal peritoneum in infertile women without any typical or 'subtle' endometriotic lesions revealed the presence of endometriosis in 6% of cases.

Endometriotic implants

Lesions can be excised with a pair of scissors. If not excised, a biopsy must first be taken to confirm the diagnosis. Coagulation of endometriosis can then be done with an argon beam coagulator (ABC) or laser. When a lesion is large, with retroperitoneal invasion, it must be excised. It is only during retroperitoneal dissection that the extent of invasion of underlying tissue can be determined.

Resection of the uterosacral ligament

The uterosacral ligaments can be involved by invasive endometriosis. This can be as large as a man's thumb with fibrotic extension down to the sacrum. Resection of the entire uterosacral ligament is the only treatment that will ensure complete removal.

Endoscopic management of ovarian endometriosis

Ovarian endometriosis is treated during first-look laparoscopy. Small (< 1 cm in diameter) endometriotic implants of the ovary are vaporised. Large (<3 cm in diameter) endometriomas are opened. The chocolate-coloured material is aspirated and the cyst irrigated. The interior wall is biopsied and vaporised to destroy the mucosal lining. The ovary is left open.

In the case of ovarian endometriosis >3 cm, the endometriotic cyst is opened, irrigated and a biopsy taken during diagnostic laparoscopy. Gonadotropin-releasing hormone agonist (GnRHa) is then given for twelve weeks.

Thereafter, a second-look laparoscopy is performed. The interior of the cyst is vaporised and left open. At the end of the procedure the pelvic cavity is copiously irrigated. Drainage alone is ineffective. Indeed, a study has shown that twelve weeks after drainage, the ovarian cyst diameter was found to be unchanged when compared to the diameter observed before drainage A pregnancy rate of 55% was achieved in moderate endometriosis and 44% in severe endometriosis during the first year after surgery.

Laparoscopic treatment of rectovaginal septum endometriosis

The main symptoms are:

• pelvic pain
• dyspareunia
• infertility

Examination with a speculum reveals either a normal vaginal epithelium, or a protruded endometriotic nodule in the posterior fornix. The size of the lesion can be determined by palpation. Palpation is very often painful and the presence of the nodule accounts for symptoms like deep dyspareunia and dysmenorrhoea.

Deep fibrotic nodular endometriosis involving the pouch of Douglas

Deep fibrotic nodular endometriosis involving the pouch of Douglas requires excision of the nodular fibrotic tissue from the posterior vagina, rectum, posterior cervix and uterosacral ligaments. The anterior rectum is dissected through the area of involvement until the loose tissue of the rectovaginal space is reached.

Dissection is then continued by removing all visible endometriotic lesions, as well as vaginal epithelium, with at least 0.5 cm disease-free margins.

In the case of rectal endometriosis with stenosis a bowel resection and anastomosis must be performed. Because of the possible need for a resection or the possibility of rectal perforation, all these patients should have bowel preparation, starting the afternoon before surgery.

Although the endometriotic lesions may not be completely eradicated by an extensive laparoscopic procedure, it may result in considerable pain relief or a desired pregnancy.