What is the optimal treatment plan for a middle-aged patient with internal soiling, a normal sigmoidoscopy, a mucosal bulge on the left side at the tip of the finger and indentation in the midline posterior on PR, and a pelvic MRI showing a mass on the left side at the level of the levator ani with no external opening?

Optimal Treatment for Complex Perianal Fistula with No External Opening

Diagnosis and Classification

Based on the clinical presentation and imaging findings, this patient has a complex perianal fistula, likely transsphincteric, extending to the levator ani muscle. The key diagnostic findings include:

• Internal cloth soiling
• Normal sigmoidoscopy
• PR examination showing mucosal bulge on the left side and posterior midline indentation
• MRI confirming a mass at the levator ani level
• No external opening

Recommended Treatment

The LIFT (Ligation of Intersphincteric Fistula Tract) procedure is the optimal treatment for this patient with a complex perianal fistula extending to the levator ani with no external opening. 1

The LIFT procedure is specifically indicated for this case because:

• It is designed for transsphincteric fistulas that extend to the levator ani level
• It offers high healing rates (60-90%) for complex fistulas 1, 2
• It preserves sphincter function, minimizing the risk of incontinence 1
• It is particularly suitable for fistulas with no external opening, as in this case

Why Other Options Are Less Optimal

1. Seton placement (Option A):

   • Setons are primarily indicated as a temporary measure to control sepsis and create a patent tract 1
   • They are typically used before definitive treatment rather than as a final solution
   • Would be more appropriate as an initial step if active inflammation or abscess were present

2. Lay open from inside (Option B):

   • This approach carries a high risk of sphincter damage and subsequent incontinence for complex fistulas at the levator ani level
   • Not recommended for complex fistulas involving a significant proportion of the anal sphincter 3

3. Sealing by glue (Option C):

   • Fibrin glue shows poor and variable healing rates (14-74%) 3
   • Not recommended as first-line therapy for complex fistulas

Treatment Algorithm

1. Preoperative Assessment:

   • Confirm the internal opening location
   • Ensure thorough MRI evaluation to identify any secondary tracts

2. LIFT Procedure Implementation:

   • Identify the intersphincteric tract
   • Ligate and divide the tract at the level of the internal sphincter
   • Curette the fistula tract
   • Close the defect at the external sphincter

3. Post-Procedure Management:

   • Monitor for healing and recurrence
   • Follow-up MRI may be considered if healing is delayed

Important Considerations

• If the LIFT procedure fails, alternative sphincter-preserving techniques could be considered as second-line options, including:

  • Video-assisted anal fistula treatment (VAAFT) with reported healing rates of 70-87% 4, 5
  • Fistula laser closure (FiLaC) with reported success rates of 66-70% 6

• The key to success with any technique is proper identification and management of the internal opening, as inadequate closure is a major cause of recurrence 5