As good as laparoscopic electrosurgical excision of endometriosis is, it will not treat pain caused by other things. Pain due to endometriosis is often described in very specific geographical or anatomical terms and is associated with specific points of tenderness on exam. These patients have the best results. If a patient cannot describe her pain accurately, or if pelvic examination does not reproduce the pain, excision of endometriosis may not provide any pain relief at all.
Other causes of pelvic pain can include non-endometriotic ovarian cysts, fibroid tumors, adhesions, adenomyosis, and other unknown factors. For this reason, there is no way to guarantee pain relief after endometriosis surgery. Cysts: The word "cyst" means a fluid-filled cavity, usually with a lining. Cysts can occur in the normal monthly functioning of the ovary. Two common types of "normal" cysts are follicular cysts, which prepare the egg, and the corpus luteum cyst, which forms after ovulation each month. Although these two types of cysts are usually temporary, each may persist longer than they should and can cause pain. Cysts don't always have to be large to cause pain. Several small cysts can occur within an ovary and cause pain by stretching the ovary slightly. If scar tissue is on the ovary, a cyst can expand and pull on the scar tissue and cause pain. A medium-sized cyst can twist on its pedicle, and this can cause pain. Other types of abnormal cysts include endometriotic and dermoid cysts. Some patients can have very large cysts and no pain at all.
When they cause pain, ovarian cysts usually cause pain off on one side or the other, and the pain can radiate slightly around the flank. A cyst which is bleeding or leaking some irritative fluid can cause generalized pelvic and lower abdominal pain which may seem to spread from the affected side. Some women can have recurrent ovarian cysts after spontaneous resolution of, or surgical removal of a cyst, since each of some 200,000 oocytes (eggs) in each ovary at birth is surrounded by a small follicle or potential cyst.
Fibroids (also called "leiomyoma") are accumulations of smooth muscle which arise within the uterine muscular wall. They expand in size somewhat concentrically, like a pearl growing in an oyster. A large fibroid would be the size of a grapefruit or larger. A small fibroid would be smaller than a marble. They can cause uterine cramping between menstrual flows and severe cramping and heavy bleeding with the flow, unless they are hanging off the outside surface of the uterus, in which case symptoms may be absent.
Fibroids sometimes cause difficulties with bowel or bladder function since they can press against the bladder or bowel if they get big enough. Low back pain can sometimes occur, since the fibroid can press against the tailbone (sacrum) and since the uterosacral ligaments can transmit uterine pain to the sacrum as well. GnRh agonists can produce a dramatic, but temporary reduction in the size of fibroids. Although fibroids can be removed surgically, some fibroids that might be too small to be seen or felt at surgery can remain in the uterus to grow and cause problems later.
Adhesions (scar tissue)
Adhesions (also called scar tissue) stick things together. They can be thin and wispy like wet tissue paper or dense and thick like hardened glue. An adhesion goes from one point in the pelvis to another point, although this distance may be functionally non-existent, as when an ovary becomes plastered to the side of the pelvis. Adhesions form after injury to the peritoneum, whether by infection, surgery, or chronic inflammation. The peritoneum is the Saran wrap-like lining of the pelvic and abdominal cavities.
Occasionally, adhesions can form without apparent reason. The tendency to form adhesions varies among patients, which is not surprising since people are different. Why some people form fewer adhesions than others with the same type of surgery is not known. Some adhesions cause pain, others do not. Some patients with extensive adhesions have no pain, whereas one small, well-placed adhesion can kink a loop of bowel and cause bowel obstruction.
When adhesions hurt, they hurt in the place they occur. Patients sometimes use terms such as "pulling" or "stretching" to describe adhesion pain. Adhesion pain would not be expected to vary with the menstrual cycle unless adhesions around an ovary get stretched by the slight growth of a cyst. Many patients with endometriosis have adhesions as well, and it is often not possible to determine whether their pain is due to adhesions or endometriosis.
After laparoscopic excision of endometriosis, 2/3 of my reoperated patients had the same or a reduced adhesion score. There is no evidence that dissection with scissors produces more adhesions than laser or electrocoagulation. In fact, a study comparing the tissue damage of laser and scissors concluded "The significant increase in tissue necrosis and the subsequent foreign body reaction that follows laser incision compared with microscissor incision lead us to conclude that sharp mechanical incision is the modality of choice."
If adhesions are present at the time of surgery, there is a good possibility they will reform in the exact location after their removal. Scar tissue develops more commonly when operating in and around the ovary and intestines. Significant adhesions rarely develop after operating strictly on the peritoneum of the pelvic floor.
INTERCEED, a cellulose fabric material, was thought to help prevent the formation of adhesions, but I discontinued its usage in my surgeries. This is because it has not actually been studied for use in endometriosis patients and 5 of 6 reoperated patients in whom INTERCEED was used had dense, vascular adhesions wherever it had been used. Also, an abstract presented at the 1991 American Fertility Society Annual Meeting showed that INTERCEED caused de novo adhesions in animals, even though no surgery was done.
Adenomyosis is a structural change within the muscular wall of the uterus which occurs when tissue resembling the uterine lining invades the muscle. The uterus can look and feel normal, yet still have adenomyosis. Neither laparoscopy nor hysteroscopy can diagnose adenomyosis, and there is no medical treatment known to eradicate it. The only widely-avialable solution to date is removal of the uterus, although a very rare patient can have an isolated area found in the uterine musculature.
Uterine prolapse, uterine retroversion
Prolapse refers to the uterus dropping down (and sometimes out of) the vagina. It is seen more commonly in women who have had children, since the childbearing process can loosen up the pelvic support structures. It is also seen more commonly in post-menopausal women, since estrogen helps supply some tone to the pelvic support structures.
Since this is a defect of ligaments, tendons, and connective tissue, it frequently does not respond well to exercise of the pelvic muscles. The pain of uterine prolapse is caused by the dropping and pulling down of the pelvic tissue, and patients frequently use terms such as "bearing down," "falling out," or "like I'm about to have a baby." Low backache and an aching sensation are sometimes mentioned. Loss of urine with sneezing, coughing, exercise, or lifting may also occur.
Retroversion is the same thing as a "tipped" uterus. The uterus lies against the rectum instead of being suspended in front by the bladder. This can lead to low backache, painful intercourse, and painful bowel movements. The painful intercourse can occur because the body of the retroverted uterus lies just beyond the end of the vagina and can get hit during intercourse like a punching bag, particularly if it is involved by adenomyosis. Painful bowel movements can occur if a retroverted uterus with adenomyosis or some other uterine problem lies against the rectum and gets scraped by stool coming through the rectum.
Oddities and unknowns
Pelvic calcifications or chronic inflammation are occasionally found instead of or accompanying endometriosis. The general distribution of these findings is identical to that of endometriosis. Although their origin is unknown, these can occasionally cause pain, since some patients with no other findings achieve pain relief when these areas are removed. Chronic inflammation is not an infection, and it does not respond to antibiotic therapy. Some patients have pain for reasons that remain unknown, even after pain relief is achieved by removal of the normal uterus, tubes and ovaries. This serves to remind us that we still don't know all we need to about the causes of pelvic pain.