[A study of the defecography]

Defecography, the radiologic examination of the defecation function, has never been reported in Japan, whereas some reports have been published in western countries. However neither the methods nor the criteria for use have been fully established. The author carried out a radiologic study focusing on the maximum lower rectal width and the ano-rectal angle by means of defecography which is considered one of the most efficient methods to examine the morphology and function of defecation. Defecography was carried out in order to study the changes in maximum lower rectal the width and the ano-rectal angle during straining and at rest both with and without the spasmolytic agent, Buscopan. The effects of using different amount of barium sulfate suspension 120 ml and 50 ml were also studied. The maximum rectal width tended to be narrowed and the ano rectal angle to increase during straining as compared to the measurements at rest, while no significant changes, were observed concerning the presence or absence of Buscopan. In comparative studies between pathologic cases such as those with constipation incontinence hemorrhoids and post operative hemorrhoids, and a normal control group, a statistically significant difference was demonstrated only in the cases with hemorrhoids. No difference was demonstrated in any of the cases in association with the use of Buscopan. The length of the anal canal was shortened by straining and was longer in males than in females. Furthermore, by using a catheter with optic fiber, the internal pressure of the anal canal was measured before defecography and it was noted that pressure was lower in older patient and patients with constipation. In conclusion, defecography is one of the most important radiologic examination procedures related to the physio-pathology of defecation.