Unusual presentation of a retrovesicular cyst

Overview: Retrovesicular and retrorectal cystic lesions are both rare entities. The following is a case report at our institution of a retrovesicular cystic lesion that presented on MRI as a retrorectal lesion with fi ndings consistent with a tailgut cyst. On surgical exploration the lesion was found to be retrovesicular and pathology confi rmed a benign cyst. Due to the unusual presentation of the retrovesicular cyst, the diff erential diagnosis of both retrovesicular and retrorectal lesions is explored with an accompanying literature review.