Recent Advances in Assessing Anorectal Structure and Functions Adil E. Bharucha, J.G. Fletcher  Gastroenterology  Volume 133, Issue 4, Pages 1069-1074 (October 2007) DOI: 10.1053/j.gastro.2007.08.051 Copyright © 2007 AGA Institute Terms and Conditions

Figure 1 Comparison of anal pressures at rest, during squeeze, and during simulated evacuation (ie, defecation) recorded by high resolution manometry in a healthy subject (left) and a woman with FI and symptoms of disordered defecation (right). The left panel reveals increased anal pressure during squeeze and anal relaxation coordinated with increased intrarectal pressure during simulated evacuation (ie, the rectoanal pressure gradient is conducive to evacuation). In comparison, the right panel shows weaker anal resting and squeeze pressures in FI. During simulated evacuation, both intrarectal and anal pressures increased. Thus, the rectoanal pressure gradient was not positive, precluding evacuation. Of interest, anal pressure increased more during simulated evacuation than during squeeze. Gastroenterology 2007 133, 1069-1074DOI: (10.1053/j.gastro.2007.08.051) Copyright © 2007 AGA Institute Terms and Conditions

Figure 2 A surface EMG probe with 16 circumferential electrodes (upper left) recorded motor unit potentials that were propagated in the direction shown by the arrows around the anal sphincter (lower left). The simultaneously recorded, synchronous, polyphasic motor unit potential recorded on needle EMG is shown in the right panel. Gastroenterology 2007 133, 1069-1074DOI: (10.1053/j.gastro.2007.08.051) Copyright © 2007 AGA Institute Terms and Conditions

Figure 3 Pelvic MR fluoroscopic images in a 10-year-old boy who had an imperforate anus repair. At rest, the anal canal was patulous (white arrow) with ultrasound gel–displaced solid stool to the proximal rectum (white arrowhead). During defecation, an enterocoele was observed (black arrow). After defecation on a commode, the distal rectum was empty, but a large amount of solid stool remained in the proximal rectum (white arrowhead). The enterocoele was even larger during a Valsalva maneuver (black arrow). Gastroenterology 2007 133, 1069-1074DOI: (10.1053/j.gastro.2007.08.051) Copyright © 2007 AGA Institute Terms and Conditions

Figure 4 Endoanal and dynamic MR proctogram in a 70-year-old woman with urinary and fecal urgency. Endoanal MR images show a partial tear and atrophy of the right puborectalis in axial and coronal sections (upper panel, arrow). Dynamic images reveal accentuation of the puborectalis indentation on posterior rectal wall, but little anterior or superior movement of the anorectal junction, consistent with puborectalis injury. During defecation, a cystocele (black arrow) and a small rectal intussusception (white arrow) were observed. Gastroenterology 2007 133, 1069-1074DOI: (10.1053/j.gastro.2007.08.051) Copyright © 2007 AGA Institute Terms and Conditions

Figure 5 An 80-year-old woman with FI with endoanal MR images showing atrophy of the subcutaneous external anal sphincter (black arrows, upper panels), and the longitudinal muscle bundles (white arrow) were more prominent. Dynamic images (lower panel) revealed a patulous anal canal at rest (white arrow), as well as a large, 5-cm anterior rectocele (white arrow) and an enterocele (black open arrow) during defecation. The rectocele did not empty during defecation. Gastroenterology 2007 133, 1069-1074DOI: (10.1053/j.gastro.2007.08.051) Copyright © 2007 AGA Institute Terms and Conditions

Figure 6 Representative examples of wall strain (A–D) and tension (E) measured by MR proctometry. Using parametric mapping, quantitative data are shown by color maps on the rectal surface. (A–D) Increasing strain during progressive distention from 50-mL (A) in 50-mL steps to 200 mL (D). Observe that strain is inhomogenously distributed on the rectal surface. (E) Rectal wall tension in same subject at 150 mL. (Reprinted with permission.) Gastroenterology 2007 133, 1069-1074DOI: (10.1053/j.gastro.2007.08.051) Copyright © 2007 AGA Institute Terms and Conditions