Endometriosis is usually diagnosed based on symptoms of the condition. However, not all women suffer from a similar combination or intensity of symptoms. In some women, there may be no underlying symptoms and diagnosis may be made during a fertility assessment, for example. Infertility is one of the major complications of endometriosis.
Generally, the diagnosis of endometriosis involves:
A detailed clinical history, history of symptoms and of menstrual cycles is obtained. Any family history of endometriosis is also asked about.
Imaging studies may be used to check for or examine the lesions that feature in endometriosis. Techniques include:
Ultrasound examination of the abdomen. This can identify large lesions, but smaller ones are often missed.
Magnetic resonance imaging (MRI) studies may provide a more detailed image of the lesions. However, small lesions may also be missed using this technique.
One of the best ways to confirm the presence of endometriosis is through inspection by laparoscopy or through surgically obtaining a biopsy of the lesion. Laparoscopy is often used to treat infertility. The lesions can be simultaneously be detected and removed all in the same surgical procedure.
The patient is usually administered general anesthesia and the abdominal cavity is inflated using a gas. An instrument called an endoscope is passed through small incisions made in the abdomen. These are long, tube-like cameras with a light source at the tip.
The surgeon views any lesions on an overhead monitor, and even the smallest of lesions can be seen. A sample of the lesion (biopsy) is removed for examination under a microscope to confirm diagnosis.
Staging of endometriosis
Once diagnosis is confirmed, endometriosis is staged I through to IV according to the Revised Classification of the American Society of Reproductive Medicine. The staging system is complex and is based on assessment of the lesions and adhesions, but not pain.
Stage I describes when superficial lesions and maybe some minimal adhesion is present; stage 2 describes mild disease, although deep lesions may be present immediately behind the uterus; stage III refers to a moderate condition where endometriosis is present on the ovaries as well as in the cul-de-sac; and stage IV describes when the lesions and adhesions present in the cul-de-sac and ovaries are large and extensive.
Reviewed by Sally Robertson, BSc