Imperforate anus: avoiding a colostomy.

Abstract

Early assessement of imperforate anus, combining clinical and radiographic data, determines the course of treatment. "High" lesions most often require combined abdominal and sacroperineal repair, usually preceded by a decompression colostomy. "Low" lesions are repaired through a perineal or sacroperineal approach not requiring a previous colostomy. Patients who do not have an apparent fistulous tract through which accurate radiographic assessment can be made frequently undergo preliminary colostomy to avoid colonic perforation. This occurs in patients who have "low" lesions and in whom colostomy may be avoided. Combining a new procedure and an old procedure may avoid unnecessary colostomy. A 14 Medicut intravenous cannula is inserted in the perineum and under fluoroscopic control is advanced into the radiolucent area identified in the pelvis as the probable lower rectal pouch. The position is confirmed by aspiration of gas or meconium and injection of contrast material. A limited contrast enema will clearly identify the level of the lesion and identify a fistula if one is present. If a low lesion is identified and no fistula is present to allow temporary colonic decompression, a fistulous tract may be created mechanically. A No. 4 Fogarty catheter is inserted through the previously placed cannula, the catheter balloon is inflated, and the entire apparatus is extracted under tension. This creates a small fistulous tract to the perineal surface. Subsequent dilation of this tract allows colonic decompression, and definitive operative repair may be planned at the most appropriate time. By employing this technique, we have avoided colostomy in 4 of 6 patients.