Fistula in ano

Fistula in ano short presentation for undergraduates

1. F istula In Ano Kishore SR Oman Medical College

2. Contents Anatomy Etiology Clinical features Assessment and Investigations Management

3. Anatomy of the Anal Canal

4. Etiology Obstruction of the Anal Gland In the vast majority of cases, fistula-in-ano is caused by a previous anorectal abscess. (cryptoglandular infection) Iatrogenic Crohn’s disease Anorectal trauma Anorectal Carcinoma Others (radiation therapy, actinomycoses, tuberculosis, and lymphogranuloma venereum secondary to chlamydial infection)

5. Clinical Features Patients often provide a reliable history of previous pain, swelling, and spontaneous or planned surgical drainage of an anorectal abscess. Signs and symptoms of fistula-in-ano, in order of prevalence, include: Perianal discharge Pain Swelling Bleeding Diarrhea Skin excoriation External opening

6. Assessment and Investigations Physical examination under Anesthesia is the mainstay of diagnosis. Digital rectal examination (DRE) may reveal a fibrous tract or cord beneath the skin Anoscopy is usually required to identify the internal opening. Proctoscopy is also indicated in the presence of rectal disease (e.g., Crohn disease or other associated conditions). MRI for high complex fistulas

7. Goodsall’s Rule

8. Management Low lying fistulas can be simply laid open and allowed to heal. In complex ones involving the sphincter, it can be probed using a lacrimal probe and seton is passed and allowed to drain. A tighter seton will gradually cut through the sphincters and allow to heal behind the seton.

9. High fistulas can be treated with an anorectal advancement flap.

10. Thank you