Comparison of Lateral Internal Sphincterotomy Techniques for Chronic Anal Fissure

NCT07520552 | Recruiting

• 1 other identifier: CAF-LIS-RCT-2026-01
• Study Type: interventional
• Target: 150
• Locations: 1 country
• Sites: 1

Brief Summary

This prospective randomized controlled trial compares three lateral internal sphincterotomy (LIS) techniques in patients with chronic anal fissure refractory to medical treatment: (1) Spasm-Controlled LIS (serial small sphincterotomies using an anal calibrator until 30 mm anal caliber is achieved, under local anesthesia plus sedation), (2) LIS up to the Fissure Apex (spinal or general anesthesia), and (3) LIS up to the Dentate Line (spinal or general anesthesia). The primary outcomes are fissure healing rate and fecal incontinence incidence at 12 months, assessed using the Wexner Incontinence Score. Secondary outcomes include postoperative pain (VAS), recurrence rate, patient satisfaction, and complications. A total of 150 patients (50 per group) will be enrolled and followed for 12 months.

Conditions

Chronic Anal Fissure

Keywords

Chronic anal fissure; Lateral internal sphincterotomy; Spasm-controlled sphincterotomy; Fecal incontinence; Dentate line; Fissure apex

Outcome Measures

Primary Outcomes (2)

• Fissure Healing Rate

  Complete epithelialization of the anal fissure with no symptoms at 12 months postoperatively, assessed by clinical examination.

  12 months

• Fecal Incontinence Incidence

  Incidence of de novo fecal incontinence assessed using the Wexner (Cleveland Clinic) Incontinence Score. A score increase of ≥1 point from preoperative baseline is defined as de novo incontinence.

  12 months

Secondary Outcomes (4)

• Postoperative Pain Score

  Day 1, Week 1, Week 2, Month 1, Month 2, Month 6, Month 12

• Recurrence Rate

  Month 6 and Month 12

• Patient Satisfaction

  Month 2, Month 6, Month 12

• Postoperative Complications

  12 months

Study Arms (3)

Spasm-Controlled LIS

ACTIVE COMPARATOR

Serial small open sphincterotomies performed under local anesthesia plus IV sedation. Anal caliber is measured with an anal calibrator before and after each increment until a caliber of 30 mm is achieved.

Procedure: Spasm-Controlled Lateral Internal Sphincterotomy

LIS up to Fissure Apex

ACTIVE COMPARATOR

Open lateral internal sphincterotomy extended to the proximal end of the fissure (fissure apex) under spinal or general anesthesia. The length of sphincterotomy equals the length of the fissure.

Procedure: Lateral Internal Sphincterotomy up to Fissure Apex

LIS up to Dentate Line

ACTIVE COMPARATOR

Open lateral internal sphincterotomy extended to the level of the dentate line under spinal or general anesthesia. This is the traditional (classical) LIS technique.

Procedure: Lateral Internal Sphincterotomy up to Dentate Line

Interventions

Lateral Internal Sphincterotomy up to Fissure Apex PROCEDURE

Open LIS extended to the proximal end of the fissure under spinal or general anesthesia.

Also known as: Tailored LIS

LIS up to Fissure Apex

Spasm-Controlled Lateral Internal Sphincterotomy PROCEDURE

Serial small open sphincterotomies under local anesthesia plus IV sedation using an anal calibrator until anal caliber of 30 mm is achieved.

Also known as: Calibrated LIS

Spasm-Controlled LIS

Lateral Internal Sphincterotomy up to Dentate Line PROCEDURE

Open LIS extended to the level of the dentate line under spinal or general anesthesia.

Also known as: Traditional LIS / Classical LIS

LIS up to Dentate Line

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Age 18 years or older
• Diagnosis of chronic anal fissure (duration ≥8 weeks)
• Failure to heal after at least 6 weeks of appropriate medical treatment (topical agents, fiber supplementation, sitz baths)
• Complete preoperative fecal continence (Wexner Incontinence Score = 0)
• Primary anal fissure (posterior or anterior midline location)
• Written informed consent

You may not qualify if:

• Any degree of preoperative fecal incontinence
• Secondary anal fissure (associated with Crohn's disease, tuberculosis, HIV, syphilis, or other systemic conditions)
• Previous anal sphincter surgery
• History of obstetric sphincter injury
• Active anorectal infection (abscess or fistula)
• Pregnancy or breastfeeding
• Uncorrectable coagulopathy or current anticoagulant use
• Inability to cooperate with study procedures or attend follow-up visits

Sponsors & Collaborators

• Çanakkale Onsekiz Mart University: lead

Study Sites (1)

Canakkale Onsekiz Mart University

Çanakkale, Çanakkale, 00017, Turkey (Türkiye)

RECRUITING

Related Publications (3)

• Elsebae MM. A study of fecal incontinence in patients with chronic anal fissure: prospective, randomized, controlled trial of the extent of internal anal sphincter division during lateral sphincterotomy. World J Surg. 2007 Oct;31(10):2052-7. doi: 10.1007/s00268-007-9177-1.

  PMID: 17665247 RESULT

• Mentes BB, Guner MK, Leventoglu S, Akyurek N. Fine-tuning of the extent of lateral internal sphincterotomy: spasm-controlled vs. up to the fissure apex. Dis Colon Rectum. 2008 Jan;51(1):128-33. doi: 10.1007/s10350-007-9121-3. Epub 2007 Dec 18.

  PMID: 18085337 RESULT

• Mentes BB, Ege B, Leventoglu S, Oguz M, Karadag A. Extent of lateral internal sphincterotomy: up to the dentate line or up to the fissure apex? Dis Colon Rectum. 2005 Feb;48(2):365-70. doi: 10.1007/s10350-004-0812-8.

  PMID: 15711861 RESULT

MeSH Terms

Conditions

Fecal Incontinence

Condition Hierarchy (Ancestors)

Rectal Diseases; Intestinal Diseases; Gastrointestinal Diseases; Digestive System Diseases

Central Study Contacts

Emre Gülçek, MD, Assistant Professor

CONTACT

+905544810964; emre.gulcek@comu.edu.tr

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: OUTCOMES ASSESSOR
• Masking Details: The surgeon performing the procedure is aware of the group allocation as blinding is not feasible for surgical technique trials. Patients are aware of their anesthesia type but are not informed of their specific group assignment until after the study. Data analysts will be blinded to group allocation during statistical analysis.
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Assistant Professor of General Surgery

Model Details: Three-arm parallel group randomized controlled trial comparing three lateral internal sphincterotomy techniques (spasm-controlled, up to fissure apex, and up to dentate line) in a 1:1:1 allocation ratio.

Study Record Dates

• First Submitted: April 3, 2026
• First Posted: April 9, 2026
• Study Start: May 6, 2026
• Primary Completion (Estimated): May 6, 2027
• Study Completion (Estimated): May 6, 2028
• Last Updated: May 14, 2026

Record last verified: 2026-05

Locations

TU (1)