192 ASIAN JOURNAL OF SURGERY VOL 28 • NO 3 • JULY 2005

070/2001

Invited Commentary

© 2005 Elsevier. All rights reserved.

The motivation to develop alternatives to lateral internal

sphincterotomy for the treatment of anal fissure rests mainly

on the risk of anal incontinence following the procedure. In

recent years, pharmacological treatment with smooth muscle

relaxants has been the most widely studied. Surgical alterna-

tives have taken the form of flap procedures that purport to

heal fissures by resurfacing and revascularization. In this issue

of the Asian Journal of Surgery, Singh et al reports a case series

using a rotational flap procedure.1 The series, though small,

describes treatment of chronic anal fissure without impair-

ment of continence. The paper does not make it clear how

successful the rotation flap was in healing anal fissure. In two

of their 14 patients, the anal fissure failed to heal. A randomized

comparison with internal sphincterotomy would have been

useful in determining technical superiority. A randomized

controlled trial comparing an advancement flap with internal

sphincterotomy in the treatment of anal fissure showed no

statistical difference in healing rate between the two.2 There

was a trend towards non-healing in the flap procedure group

due to flap failure. Interestingly, no incontinence was reported

in either group.

There has been a tendency to over-emphasize the risk of

incontinence following internal sphincterotomy. A 2% rate of

anal incontinence has been reported with tailored sphincter-

Internal Sphincterotomy Versus Rotation Flap to TreatChronic Anal Fissures

otomy where there was careful attention to the amount of

sphincter divided.3 A prospective trial of lateral internal sphinc-

terotomy reported by Hyman showed similarly low rates of

incontinence, with even fewer patients reporting an impair-

ment in quality of life.4 Despite the grim prognostication of

advocates of medical and flap alternatives, lateral internal

sphincterotomy is some way from becoming a relic of surgery

for anal fissure.

Flap procedures have a role in the treatment of anal fissure

in cases where incontinence is a genuine risk following

sphincterotomy. Examples of this would include female pa-

tients with short anal canals and the elderly or multiparous

who already have a degree of impaired anal continence.

References

1. Singh M, Sharma A, Duthie G, et al. Early results of a rotation flapto treat chronic anal fissures. Asian J Surg 2005;28:189–91.

2. Leong AFPK, Seow-Choen F. Lateral sphincterotomy comparedwith anal advancement flap for chronic anal fissure. Dis Colon Rectum1995;38:69–71.

3. Littlejohn DR, Newstead GL. Tailored lateral sphincterotomy foranal fissure. Dis Colon Rectum 1997;40:1439–42.

4. Hyman N. Incontinence after lateral internal sphincterotomy: aprospective study and quality of life assessment. Dis Colon Rectum2004;47:35–8.

Adrian Leong, Department of Surgery, National University Hospital, Singapore.

Address correspondence and reprint requests to Professor Adrian Leong, Department of Surgery, National UniversityHospital, 5 Lower Kent Ridge Road, Singapore 119074.E-mail: surhead@nus.edu.sg • Date of acceptance: 29 April 2004