Manometric and clinical evaluation of patients after low anterior resection for rectal cancer.

The aim of this study was to examine the anorectal physiological and clinical changes that occur after low anterior resection for rectal cancer. Since 1998, 30 patients underwent laboratory tests of anorectal function, preoperatively and 1 month and 6 months after low anterior resection. Postoperatively all patients presented with increased bowel frequency, 60% of the patients with mild soiling and 30% with urgency for defecation. Six months after surgery there was a significant improvement of these symptoms. The anal resting pressure was significantly decreased postoperatively, while maximum squeezing pressure remained unchanged. The rectoanal inhibitory reflex was absent in 80% of the patients and at 6 months after surgery it tended to recover. Rectal capacity and compliance were reduced in all patients. In the current study, the majority of patients demonstrated manometric anorectal changes and clinical anorectal function disorders during the first year after surgery. We observed that these disorders correlated with the low level of the anastomosis.