Transperineal Sonography of Anal Mass Status Post Total Colectomy: A Case Report

Abstract

Transperineal sonography is a diagnostic imaging tool used to evaluate the pelvic floor and lower pelvis. 1,2 This approach allows visualization of the urethra, vagina, anorectum, lower uterus, and base of the bladder without insertion of a vaginal or rectal transducer. Indications for transperineal sonography include perineal pain, perineal trauma, vaginal or anorectal obstruction, lower pelvic tumors, abnormal urination or defecation, and pelvic floor dysfunction. 1 This sonographic approach is also useful for image-guided lower pelvic procedures, evaluation of perianal disease in patients with Crohn's disease, assessment of anal sphincter integrity, and assessment of cervical length and fetal head position during pregnancy. 1,3-6 Adequate visualization of the muscles of the male pelvic floor with transperineal sonography has been reported. 7 Evaluation of congenital abnormalities of the lower urinary, gynecologic, and intestinal systems has been reported in pediatric patients. 8,9 When internal sonography is contraindicated, such as for patients who have undergone recent perineal or pelvic surgery, patients with dyspareunia or vaginal pain, pregnant patients with suspected ruptured membranes, or patients with vaginal obstruction, transperineal imaging may be a useful alternative. This technique may also be useful when computed tomography (CT) or magnetic resonance (MRI) imaging is contraindicated, nondiagnostic, or indeterminate. Transperineal sonography also provides higher spatial resolution than CT or MRI. 10