What is the definitive diagnostic procedure for a patient suspected of having endometriosis?

The definitive diagnostic procedure for a patient suspected of having endometriosis is laparoscopy with biopsy. This minimally invasive surgical procedure allows direct visualization of the pelvic organs and tissues, enabling the clinician to identify endometrial-like tissue outside the uterus. Laparoscopy also permits the collection of tissue samples for histological analysis, which is essential for confirming the diagnosis of endometriosis.

While imaging techniques such as pelvic ultrasound and CT scans can suggest the presence of endometriosis or help identify ovarian cysts associated with the condition, they cannot confirm the diagnosis. The CA-125 blood test is also not definitive for diagnosing endometriosis, as elevated levels of this marker can occur in various conditions, including ovarian cancer and other benign diseases.

In contrast, laparoscopy provides a clear visual assessment and the opportunity to directly diagnose and potentially treat endometriosis in a single procedure, making it the gold standard in the evaluation of suspected cases.