[Imperforate anus. Principles and methods of surgical treatment]

Imperforate anal surgery is not only concerned with survival but also with the problem of incontinence. The ideal long term result must be fecal continence without constipation or fecal soiling. As a result of embryological studies new anatomical and physiological concepts form the basis of our present knowledge concerning diagnosis and surgical approach. A new classification of anorectal anomalies evolved in 1970. It is based on the anatomy of the visceral deformities in relation to the principal muscle of continence, the puborectalis part of the levator ani muscle. The primary divisions are those of the high rectal lesions above the levator muscle (supralevator), and those of the low anal lesions through the levator (translevator). The translevator type will be corrected through a perineal approach. The prognosis is excellent. The supralevator type needs a combined abdominoperineal operation. The continence prognosis of this type still raises problems. Only a good knowledge of these basic concepts and a careful dissection of every sphincteric muscle will ameliorate our results.