High-resolution Anorectal Manometry for Acquired Megarectum in a Patient With Parkinson's Disease

CC This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons. org/licenses/by-nc/3.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. Figure 1. Abdominopelvic CT revealed fecal impaction in a megarec-tum. Figure 2. The average resting anal pressure (4.7 mmHg) and maximum squeezing pressure (17.8 mmHg) were low. During defecation, high-resolution anorectal manometry showed incomplete relaxation of the anal sphincter with inadequate propulsive force. During rectal balloon distension, the rectoanal inhibitory reflex was present. A 74-year-old woman previously diagnosed with Parkinson's disease visited the hospital complaining of progressively worsening difficulty with defecation. She had a long history of constipation. A digital rectal examination revealed a hard mass of stool in the rectum. Abdominopelvic CT revealed a large amount of fe-cal material in a megarectum (Fig. 1). High-resolution anorectal manometry (with balloon expulsion was performed. The HR-ARM showed a low mean resting anal pressure, the maximum squeezing pressure, and incomplete anal relaxation with inadequate propulsive force during defecation suggesting type IV pelvic floor dyssynergia (Fig. 2). 1 During the rectal bal