“Perineal Canal”: A Rare Anorectal Malformation of Variable Complexity

Abstract

Introduction: Perineal canal (PC) is a fistulous tract that communicates the anus with the vulvar vestibule. Our aim is to show the variable spectrum of complexity of this caudal malformation. Patients and Methods: Patient 1 had a single urogenital orifice and a normal anus. After sigmoidostomy, a uterovaginal duplication was discovered upon opening the canal that was repaired at puberty. Patient 2 had a single urogenital orifice, a huge dilatation of a single vagina and an apparently normal anus. During perineal operation without diversion, the true anus was found which opened into the PC. Patient 3 had a single urogenital orifice, a uterovaginal duplication and an apparently patent anus. After colonic diversion, the PC was taken down revealing a normal urethral opening, the absence of an anus and a high rectovaginal fistula at the intervaginal wall. A posterior sagittal approach allowed extensive mobilization of the fistula and the rectum, fashioning of a single vagina and positioning of the rectum within the striated muscle complex. Results: The cosmetic results were satisfactory. Patients 1 and 2 have normal continence and a near-normal perineal anatomy. Patient 3 is too young to assess continence. Conclusions: 1) Perineal canal is a malformation that may involve the genitourinary system as well as the rectum and perineum. This developmental disturbance of the caudal end is profound as judged by the vaginal duplication and the nearly cloacal pattern of some cases. 2) Repair may be as challenging as that of a regular cloaca requiring an individualized approach.

Key words

perineal canal - female - anorectal malformation - double vagina

References

• 1 Chatterjee S K. Double termination of the alimentary tract – a second look.  J Pediatr Surg. 1980;  15 623-627
• 2 Ismail A. Perineal canal: a simple method of repair.  Pediatr Surg Int. 1994;  9 603-604
• 3 Kulshrestha S, Kulshrestha M, Prakash G, Gangopadhyay A N, Sarkar B. Management of congenital and acquired H-type anorectal fistulae in girls by anterior sagittal anorectovaginoplasty.  J Pediatr Surg. 1998;  33 1224-1228
• 4 Mirza I, Zia-ul-Miraj M. Management of perineal canal anomaly.  Pediatr Surg Int. 1997;  12 611-612
• 5 Murphy F, Puri P, Hutson J M, Holschneider A M. Incidence and frequency of different types and classification of anorectal malformations. Holschneider AM, Hutson JM, eds. Anorectal malformations in children: embryology, diagnosis, surgical treatment, follow-up. Berlin, Heidelberg; Springer Verlag 2006: 163-184
• 6 Rao K LN, Choudhury S R, Samujh R, Narasimhan K L. Perineal canal: repair by a new surgical technique.  Pediatr Surg Int. 1993;  8 449-450
• 7 Rintala R J, Mildh L, Lindahl H. H-type anorectal malformations: incidence and clinical characteristics.  J Pediatr Surg. 1996;  31 559-562
• 8 Stephens F D, Smith E D. Ano-rectal malformations in children. Chicago; Year Book Medical Publishers 1971
• 9 Stephens F D, Smith E D, Hutson J M. Congenital anomalies of the urinary and genital tracts. Oxford; Isis Medical Media 1996
• 10 Tsuchida Y, Saito S, Honna T, Makino S, Kaneko M, Hazama H. Double termination of the alimentary tract in females: a report of 12 cases and a literature review.  J Pediatr Surg. 1984;  19 292-296
• 11 Tsugawa C, Nishijima E, Muraji T, Satoh S, Kimura K. Surgical repair of rectovestibular fistula with normal anus.  J Pediatr Surg. 1999;  34 1703-1705
• 12 Wakhlu A, Pandey A, Prasad A, Kureel S N, Tandon R K, Wakhlu A K. Anterior sagittal anorectoplasty for anorectal malformations and perineal trauma in the female child.  J Pediatr Surg. 1996;  31 1236-1240
• 13 White J J, Haller Jr J A, Scott J R, Dorst J P, Kramer S S. N-type anorectal malformations.  J Pediatr Surg. 1978;  13 631-637