In suspected endometriosis, which imaging modality is noninvasive and considered the test of choice?

• A. Laparoscopy
• B. Transvaginal ultrasonography
• C. MRI
• D. CT

Answer: (B)

Transvaginal ultrasonography is the first-line, noninvasive imaging test for suspected endometriosis. It provides high-resolution visualization of the pelvis, including the ovaries, uterus, and surrounding structures, and is readily available, cost-effective, and free of radiation. It is especially good at detecting ovarian endometriomas and other pelvic lesions that suggest endometriosis, and it helps guide further management.

Laparoscopy is invasive and can definitively diagnose endometriosis with direct visualization and biopsy, so it’s the gold standard but not the initial noninvasive test. MRI offers excellent detail, particularly for deep infiltrating disease, but is typically reserved for complex cases or when TVUS findings are inconclusive. CT has limited utility for endometriosis due to poorer soft-tissue contrast and radiation exposure.