Posterior Sagittal Approach for Nonanorectal Malformation: Widening Spectrum

Abstract

Background:

Posterior sagittal is a very well accepted approach in the treatment of anorectal malformations. This approach provides good access and exposure through the perineum to the deep pelvic structures. It reduces risk of injury to important structures as dissection remains in midline.

Aims and Objectives:

To access feasibility of posterior sagittal approach for non-anorectal malformation indications and to widen the spectrum.

Material and Methods:

We present a series of 10 cases of non-anorectal malformations operated by this approach for 4 years.

Results:

Six patients included in the study were of Disorders of Sexual Differentiation with pseudovagina, three of Y duplication of the urethra, and one of cervical atresia. All patients had good results.

Conclusion:

Posterior sagittal approach is feasible, safe with minimal bleeding, and no postoperative incontinence. It can safely be used for non-anorectal indications.

INTRODUCTION

Posterior sagittal anorectoplasty (PSARP) technique was innovated for the repair of anorectal malformations. It provides a complete exposure of the region by means of a median sagittal incision that runs from the sacrum to the anal dimple, splitting the sphincter muscle complex behind the rectum. The basic principle underlying this procedure is to obtain the fullest possible exposure of all perineal and low pelvic structures while staying in the midline to avoid damaging the neurovascular structures, vas deferens, ectopic ureters, etc.[1] Peña himself suggested different indications for PSARP and proposed a posterior sagittal transanorectal approach.[2] The rectum is bivalve in the midline, including both anterior and posterior rectal walls, without the need to mobilize it.

Similarly, Di Benedetto et al.[3] and Dòmini et al.[4] further modified this approach and proposed a safer anterior sagittal transanorectal approach; a sagittal incision of only the anterior wall of the rectum provides an excellent exposure of the pelvis and minimizes the risk of incontinence. Posterior and anterior sagittal transanorectal or perirectal approaches are minimal variations of the original technique introduced by Peña. The urogenital sinus, urethra, and vagina can be easily approached through these incisions. Therefore, these approaches have been used by many surgeons in children and adults for treating diseases other than Anorectal malformation (ARM), including pseudohermaphroditism and other Disorders of Sexual Differentiation (DSD), Hirschsprung's disease, trauma, recurrent rectal prolapse, rectal duplication, anorectal cancer, anal canal-acquired stenosis, and presacral masses.[3,4,5,6,7,8,9]

We have used posterior sagittal pararectal approach and recommend that this approach can safely be used for cases in which the deep pelvic structures need to be accessed. Not much have been written in the literature for widening of spectrum of use of this approach; hence, we desire to share our experience emphasizing the usefulness of this approach to nonanorectal malformations by presenting this case series.

MATERIALS AND METHODS

We evaluated retrospectively 10 patients of nonanorectal malformations operated by posterior sagittal approach in the department of pediatric surgery at a tertiary care center for 4 years. The average age at surgery was 9 years (1–13 years). Ten patients, including six patients of dilated prostatic utricle (symptomatic with recurrent urinary tract infection and inability to catheterize), three of Y-duplication of the urethra, and one of cervical atresia, were included. Patients of anorectal malformations were excluded [Table 1]. All the patients were followed up for 1 year in terms of effectivity of the procedure, continence, and cosmesis.

Table 1.

Case description of patients included in study

Case number	Age	Diagnosis	Colostomy	Cosmesis	Continence
1 [Figure 1]	13 years	46XX CAH simple virilizing	No	Excellent	Satisfactory
2	9 years	MGD	No	Excellent	Satisfactory
3	12 years	46XX CAH simple virilizing	No	Excellent	Satisfactory
4	12 years	MGD	No	Excellent	Satisfactory
5 [Figure 2]	1 year 1 month	Y-duplication of the urethra	Yes	Good	Satisfactory
6	3 years	Y-duplication of the urethra	Yes	Good	Satisfactory
7 [Figure 3]	13 years	Cervical atresia	Yes	Good	Satisfactory
8	10 years	MGD	No	Excellent	Satisfactory
9	9 years	Y-duplication of the urethra	Yes	Excellent	Satisfactory
10	11 years	46XX CAH simple virilizing	No	Excellent	Satisfactory

MGD: Mixed gonadal dysgenesis, CAH: Congenital adrenal hyperplasia

Figure 1.

Excision of pseudovagina

Figure 2.

Y-duplication of the urethra

Figure 3.

Uterovaginal anastomosis

Six patients of DSD underwent primary workup for DSD and cystogenitoscopy to look for the length of dilated prostatic utricle, and then, excision of the dilated utricle was done through posterior sagittal approach. During the procedure, cystoscopic-guided Foley was placed per urethrally and one in the prostatic utricle for easy identification during dissection, followed by posterior sagittal perirectal dissection to identify pseudovagina which was excised, and the urethra was repaired. Incision was closed taking care of sphincters. All patients had per urethral catheter in place for 15 days. Postoperative period was uneventful, and follow-up voiding cystourethrogram (VCUG) showed no diverticulum/stricture. Anal continence was well-preserved.

Three patients of Y-duplication of the urethra diagnosed on VCUG and cystoscopy underwent diverting colostomy, followed by definitive procedure after 6 weeks. Rectourethral fistula was disconnected, and perineal urethrostomy was made in three cases, and in a girl, the ventral urethra was of adequate size; hence, primary anastomosis was done with accessory urethra.

One patient of cervical atresia diagnosed on cystogenitoscopy, diagnostic laparoscopy, and magnetic resonance imaging underwent uterovaginal anastomosis through posterior sagittal approach. There was rectal injury in this case; therefore, diverting colostomy was made intraoperatively, which was closed after 6 weeks. The patient had transanastomotic in place for 3 months, during which she menstruated twice. Genitoscopy, 6 weeks after removal of stent, showed patent uterovaginal anastomosis.

None of the patients had fecal soiling, and all had preserved voluntary bowel movement (Krickenbeck continence score).

DISCUSSION

Posterior sagittal approach, formerly described for anorectal malformation, can be used for other procedures as it gives an excellent access to the lower pelvic structures, perirectal pouches, and urogenital structures. Sphincters are usually well-preserved, provided there is no need to mobilize the rectum. Yoo et al., in an experimental study in 1995, suggested that resection of the internal anal sphincter (IAS) did not completely interfere with fecal continence, and the smooth muscle of pulled-through rectum seemed to partly take over the function of the IAS; thus, the posterior sagittal approach with perirectal dissection seems not to impair fecal continence in children if reconstruction is performed meticulously.[10] Thus, in agreement with the literature, the spectrum of use of this approach can be expanded to various nonanorectal malformations which require exposure to pararectal, presacral, lower pelvic spaces, urogenital organs, and surgeries of rectum other than ARM. Perineal sagittal approaches are safe enough to allow perirectal or transrectal dissection. It is a safe, feasible, and reproducible approach with better functional outcomes. We performed a posterior sagittal approach with perirectal dissection in patients of DSD for excision of dilated prostatic utricle, cases of Y-duplication of the urethra, and in a case of cervical atresia. Although the study was carried out on a small number of patients, it confirmed that these approaches can be used safely for diseases other than ARM involving the perineum and urogenital structures.

CONCLUSION

Posterior sagittal approach is feasible, safe with minimal bleeding, and no postoperative incontinence. It can safely be used for nonanorectal indications, and the spectrum can keep on expanding.