Anal fissure

Question 1

Definition

Answer 1

Tearing in the lining of the anus/anal canal
Acute < 6 weeks
Chronic > 6 weeks

Question 2

Pathophysiology

Answer 2

Majority occur on the posterior mid-line of anal canal.
- Primary = no clear underlying cause. Could be associated with lack of nitric oxide which is needed for sphincter relaxation or increased internal anal sphincter tone affecting blood flow -> local ischaemia.
Secondary = associated with identifiable underlying cause (constipation, IBD, malignancy, STI, infection, anal trauma and pregnancy and childbirth).

Question 3

Clinical Features

Answer 3

Tearing sensation on passing stool
Pain on defecation
PR bleeding (fresh red)
Anal spasm
Skin tags (chronic)

Question 4

Investigations

Answer 4

Clinical diagnosis
Anal manometry (low resting pressure)
Anal ultrasound (defects in sphincters)

Question 5

Treatment

Answer 5

• Conservative: management (high fibre diet + increase fluids + stool softeners + analgesia)
• Topical glyceryl trinitrate or diltiazem
• Chronic = botox injections and surgery