Three-dimensional endoanal ultrasonography of the anorectal region

Abstract

Anorectal imaging has become an integral part of the assessment of posterior compartment disorders. Following detailed history and examination, the patient should be offered anal sphincter imaging(either 2D or 3D endoanal ultrasonography). Even though anorectal physiological studies indicate dysfunction of the anal sphincter complex, they do not identify the anatomical site and the degree of anal sphincter disruption. Endoanal ultrasound has been defined the gold standard investigation for detecting anal sphincter injuries infecal incontinence and it is also used in the follow-up after primary sphincter repair or injection of bulking agents. Endoanal ultrasound represents a good modality for the preoperative and intraoperative investigation of perianal abscesses and fistulas and may guide the surgical treatment. In recent years, echodefecography has been developed as alternative to defecography and dynamic MRI for the evaluation of obstructed defecation syndrome and posterior vaginal wall prolapse.