Role of magnetic resonance defecography in the assessment of obstructed defecation syndrome

Figure 12  Dyssynergic defecation. A: Sagittal true fast imaging with steady-state free precession image at rest demonstrates an anorectal angle (ARA) of greater than 90°; B: During the squeeze maneuver there is reduction in ARA; C: During the strain phase ARA reduces further; D: During the defecation phase, there is further paradoxical reduction in the ARA, with failure of the anal canal to open up.