Diagnosis of Non-relaxing Puborectalis Syndrome by using the Manometric Defecation Index

ABSTRACT

PURPOSE: Currently, various tools are used for the diagnosis of nonrelaxing puborectalis syndrome (NRPRS), one of major causes of chronic constipation. Defecography, electromyography (EMG), balloon expulsion test, and a colon transit time study one examples of such tools, but none can be said to be the most accurate and effective one. A diagnosis is only made when two or more examinations show positive findings simultaneously. The aim of this study is to assess the correlation between EMG and the manometric defecation index (DI), which is a relatively new parameter, for the diagnosis of NRPRS. METHODS: Forty-two chronically cornstipated patients without any history of anal or abdominal surgery underwent both anorectal manometric and EMG tests. The manometric defecation index (DI) was defined as the ratio between the peak rectal pressure and the peak anal pressure when the pressures were measured simultaneously during push by the catheter with longitudinally arranged side holes. The ratio of EMG activity was defined as the ratio between the peak amplitude during push and the peak amplitude during rest when EMG activities were measured by using an anal plug electrode. The two variables were compared prospectively, and their correlation was analyzed. RESULTS: The manometric DI and the ratio of EMG activit in 42 patients were 0.80+/-0.75 and 1.50+/-0.65, respectively. The correlation coefficient between the two variables was -0.50 (P= 0.001). CONCLUSIONS: The manometric DI and the ratio of EMG activit were correlated significantly. Therefore, it can be said that the anorectal manometric test can replace the EMG test for diagnosis of NRPRS, which has less convenient access for most colorectal surgeons.