1. Anal Fissure

2. Definition:_
Anal fissure is an elongated ulcer in the long axis of the lower anal canal.
Location:-
Midline posteriorly 90%
Midline anteriorly
Aetiology
Hard faecal mass – when expelled stretches the mucosa  tear. Damaged pelvic floor an attenuated perineal body
Ischaemia is supposed to be a cause.
Initiated by trauma by hard mass sustained by poor blood supply.

3. An incorrectly performed haemorrhoidectomy where too much skin is removed. Scar stenosis
Tearing – fissure
Pathology :
Acut or chronic
Situated in the sensitive lower half of the anal canal.
Acute anal fissure has no underlying induration
Chronic anal fissure has underlying induration
The fissure looks like a boat shaped ulcer
At the inferior end there may be a skin tag called the ‘sentinel pile’
Spasm of the involuntary musculature of the internal sphincter.
Infection  abscess  fistula may form

4. Chronic fissure may have a specific cause like Crohn’s disease or tuberculosis
Clinical Features
Pain on defaecation
Bright red bleeding
Mucus discharge
Constipation
More common in women
During the meridian of life
Uncommon in the aged because of the poor muscle tone.
Fissure is not rare in children. May be a cause of acquired megacolon.

5. Pain is sharp, agonising
Pain is sharp, agonising. Starting during defaecation often overwhelming in intensity and lasting for an hour or more. As a rule it ceases suddenly and the sufferer is comfortable until the next action of the bowel.
Patient tends to be constipated thinking of the agonising pain.
Bleeding usually slight and consists of bright streaks on the stools.
Discharge – slight discharge

6. Spastic anus looks puckered
PR contraindicated when the pain is severe – to be done only under surface anaesthesia.
To establish the diagnosis beyond doubt general anaesthesia is needed.
Differential Diagnosis
Carcinoma of the anus – in the very early stages easily simulates a fissure.
Multiple fissures skin diseases, scratching and inflammatory bowel disease, as well as homosexual practices (sodomy, fisting and the use of anorectal sex toys)
Look for AIDS

7. Treatment
Conservative treatment : Glyceryl trinitrate as an ointment  relaxes the internal sphincter. Causes healing.
Laxatives
Stools should not be made watery (celevac tabs)
Surgical Treatment
Lateral sphincterotomy : Open / Closed

10. Lateral Internal Sphincterotomy - anal fissure surgery for patients with chronic symptoms  In this procedure, a small portion of the distal internal sphincter is divided in order to relieve chronic spasm. The procedure is very successful in curing a patient of chronic anal fissure. However, there are occasional changes in continence with this procedure so it is reserved only for patients who have failed conservative therapy.