Imaging and clinical assessment of functional defecatory disorders with emphasis on defecography

• Published in: Abdominal imaging Vol. 46; no. 4; pp. 1323 - 1333
• Main Authors: Lalwani, Neeraj, El Sayed, Rania Farouk, Kamath, Amita, Lewis, Sara, Arif, Hina, Chernyak, Victoria
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.04.2021; Springer Nature B.V
• Subjects: Anorectal; Balloon treatment; Constipation; Contraction; Defecation; Diagnostic software; Diagnostic systems; Disorders; Epidemiology; Etiology; Evaluation; Excretion; Expulsion; Fecal incontinence; Gastroenterology; Hepatology; Imaging; Medical diagnosis; Medical imaging; Medicine; Medicine & Public Health; Muscle contraction; Muscles; Radiology; Rectum; Special Section: Pelvic Floor; Sphincter; X-rays; Defecography; Functional defecatory disorder; Outlet obstruction; Constipation; Dyssynergia
• ISSN: 2366-004X; 2366-0058
• DOI: 10.1007/s00261-019-02142-9

Functional defecation disorders (FDD) encompass causes of constipation associated with anorectal dysfunction, which include dyssynergia or inadequate defecatory propulsion. FDD are frequently encountered in clinical practice and may affect up to 33–50% of patients with chronic constipation. The etiology of FDD is unclear, however, it has been defined as an acquired, but subliminal behavioral disorder. Pathophysiologic mechanisms may include discoordination of rectoanal muscles, paradoxical contraction or insufficient relaxation of puborectalis and/or anal sphincter during defecation, and sluggish colonic transit. A combination of comprehensive clinical assessment, digital rectal examination and a battery of physiologic tests are needed to make an accurate diagnosis of FDD. Defecography may play a crucial role in the evaluation of FDD, especially when a balloon expulsion test (BET) and/or anorectal manometry (ARM) are equivocal or demonstrate contradictory results. In this review, we provide a thorough overview of the epidemiology, pathophysiology, diagnostic criteria, clinical and imaging evaluation, and treatment options for FDD, with an emphasis on available diagnostic imaging tools such as defecography and conventional fluoroscopic methods.