Post-Fistulotomy Anal Asymmetry Assessment
The asymmetrical appearance of your anal opening with leftward shift is an expected anatomical consequence of the transsphincteric fistulotomy you underwent, representing the healed surgical tract rather than a complication requiring intervention. 1, 2
Understanding the Anatomical Changes
What you're observing is normal post-fistulotomy anatomy:
- The "shifted" or "open more on the left" appearance represents the healed fistulotomy tract where the fistula was laid open surgically 1, 3
- This creates an intentional asymmetry as the fistula tract has been converted from a closed tunnel into an open groove that heals from the base upward 4, 3
- The healed tract undergoes complete epithelialization over 6-12 months, creating fibrotic scar tissue that is actually stronger than the original diseased fistula tract 5
Critical Distinction: Keyhole Deformity vs. Normal Healing
Your description does not suggest pathological keyhole deformity, which would present differently:
- True keyhole deformity occurs when excessive sphincter division creates a permanent notch or "keyhole" shape with associated symptoms like anal pruritus, fecal soiling, or minor incontinence 6, 3
- The ECCO-ESCP guidelines specifically warn that cutting setons (not standard fistulotomy) cause keyhole deformity with 57% incontinence rates 6
- Since you maintain continence and the asymmetry is only visible when manually spreading the buttocks, this represents normal post-surgical anatomy rather than deformity 1
When Asymmetry Becomes Concerning
You should seek evaluation if you develop:
- Any degree of fecal incontinence (solid, liquid, or gas) 6
- Persistent anal pruritus or fecal soiling that interferes with hygiene 3
- Pain or discomfort suggesting active inflammation or abscess recurrence 6
- Signs of proctitis (rectal bleeding, mucus discharge, urgency) which would contraindicate any further surgical intervention 6, 1
Diagnostic Evaluation if Symptoms Develop
If you experience functional problems, the following assessments are indicated:
- Anorectal manometry to quantify sphincter pressures (normal: mean resting pressure >50 mmHg, maximum squeeze pressure >100 mmHg for males) 1
- Endoanal ultrasound to assess for structural sphincter defects, active inflammation, or fluid collections 1
- Evaluation for active proctitis, as this would explain persistent symptoms and contraindicate further surgery 6, 1
Expected Timeline and Prognosis
The healing process follows a predictable course:
- Complete epithelialization typically requires 6-12 months after fistulotomy 5
- The remodeled tissue provides superior structural integrity compared to the diseased tissue that was removed 5
- Once fully healed, the fibrotic scar tissue is mechanically stronger than the original chronic inflammatory tract and unlikely to cause problems with normal activities 5
- Complete restoration of perfectly symmetrical anatomy may not be achievable given the extent of sphincter division during fistulotomy, even though continence is preserved 1
Management if Symptomatic
If you develop sphincter hypertonicity or discomfort:
- Apply topical 0.3% nifedipine with 1.5% lidocaine ointment three times daily for at least 6 weeks to reduce sphincter hypertonicity and promote healing, with expected symptom relief after 14 days 6, 1
- Oral analgesics (paracetamol or ibuprofen) should be added for severe discomfort episodes 6, 1
- Sphincter hypertonicity typically improves over 6-12 months with conservative management including topical calcium channel blockers and pelvic floor exercises 1
Common Pitfalls to Avoid
Do not pursue unnecessary interventions:
- Avoid aggressive examination or probing of the healed tract, as this causes iatrogenic complications 2
- Do not request revision surgery for cosmetic asymmetry alone without functional symptoms, as this risks creating actual incontinence 6
- Recognize that some degree of visible asymmetry is the trade-off for successful fistula eradication while preserving continence 1, 5