Anal fissure

Question 1

What is an anal fissure?

Answer 1

• Tear in mucosal lining of anal canal
• Commonly due to trauma from defecation of hard stool

Question 2

Acute vs chronic anal fissure

Answer 2

• Acute - present for less than 6 weeks
• Chronic - more

Question 3

Categories of anal fissures

Answer 3

• Primary - no underlying disease
• Secondary - to underlying diease eg IBD

Question 4

RF for anal fissure

Answer 4

• Constipation
• Dehydration
• IBD

Question 5

Symptoms of anal fissure

Answer 5

• Intense pain post
  defecation - can last several hours
• Pain can be far out of proportion to size of fissure
• Can also get bleeding (bright red blood wiping), or itching

Question 6

Examination of anal fissure

Answer 6

• Visible or palpable - but painful
• Posterior midline is most common location
• Anterior fissures higher in females (esp after childbirth) or if underlying disease
• Often refuse DRE so sometimes need EUA, if within anal canal may need proctoscopy

Question 7

What to do if someone has multiple anterior fissures?

Answer 7

• Often sign of underlying disease
• May need further investigations for this

Question 8

Medical management anal fissure

Answer 8

• Increase fluid and fibre intake
• Laxatives can be tried - bulk forming are 1st line, if not tolerated –> lactulose
• Topical anaesthetics eg lidocaine can help or other analgesia
• GTN cream or diltiazem cream - increase blood supply to region, relaxing internal anal sphincter putting less pressure on fissure = promote healing and relieve pain

Question 9

Surgery for anal fissures

Answer 9

• Done for chronic fissures where medical management failed
• Botox injections to internal anal sphincter - relax and promote healing
• If ongoing despite this - lateral sphincterotomy - dividing internal anal sphincter muscle

Cut along dotted line