Bladder Endometriosis: Ultrasound and MRI Findings

Bladder endometriosis is a rare cause of a localized bladder mass, potentially mimicking a neoplasm at cross-sectional imaging. We present the case of a patient with cyclic pelvic pain and urinary symptoms secondary to bladder endometriosis, with characteristic pelvic ultrasound and magnetic resonance imaging findings. Potential pathological mechanisms are discussed.