Niche role of MRI in the evaluation of female infertility.

Infertility is a major social and clinical problem affecting 13-15% of couples worldwide. The pelvic causes of female infertility are categorized as ovarian disorders, tubal, peritubal disorders, and uterine disorders. Appropriate selection of an imaging modality is essential to accurately diagnose the aetiology of infertlity, since the imaging diagnosis directs the appropriate treatment to be instituted. Imaging evaluation begins with hystero- salpingography (HSG), to evaluate fallopian tube patency. Uterine filling defects and contour abnormalities may be discovered at HSG but usually require further characterization with pelvic ultrasound (US), sono-hysterography (syn: hystero-sonography/saline infusion sonography) or pelvic magnetic resonance imaging (MRI), when US remains inconclusive. The major limitation of hysterographic US, is its inability to visualize extraluminal pathologies, which are better evaluated by pelvic US and MRI. Although pelvic US is a valuable modality in diagnosing entities comprising the garden variety, however, extensive pelvic inflammatory disease, complex tubo-ovarian pathologies, deep-seated endometriosis deposits with its related complications, Mulllerian duct anomalies, uterine synechiae and adenomyosis, often remain unresolved by both transabdominal and transvaginal US. Thus, MRI comes to the rescue and has a niche role in resolving complex adnexal masses, endometriosis, and Mullerian duct anomalies with greater ease. This is a review, based on the authors' experience at tertiary care teaching hospitals and aims to provide an imaging approach towards the abnormalities which are not definitively diagnosed by ultrasound alone.