Human body organs: Anal Fissure

Monday, March 16, 2015

It is an ulcer in the longitudinal axis of the lower anal canal.

Location

Causes

Due to the curvature of the sacrum and rectum, hard fecal matter while passing down causes a tear in the anal valve leading to posterior anal fissure.
Anterior anal fissure is common in females due to lack of support to the pelvic floor.
Haemorrhoidectomy
IBD- esp. chron’s disease
STD

Pathology

It can be acute and chronic. Fissure ends above at the dentate line.
Acute anal fissure
It is a deep tear in the lower anal skin with spasm of anal sphincter with little inflammatory induration or edemaof its edges.
Chronic anal fissure
It has got inflamed, indurated margin with scar tissue.
Ulcer at its inferior margin is having a skin tag, which is edematous, acts like a guard-’ Sentinel Pile’
It can cause repeated infection-fibrosis-abscess foramtion-fistula formation.

Clinical features

Common in middle aged women, not in elderly.
Pain is severe in nature in acute type, whereas less severe in chronic.
Constipation, bleeding and discharge.
O/E
In standing cases there may be sentinel skin tag. Sentinel skin tag + typical Hx + tightly closed, puckered anus= pathognomonic.
In chronic fissure, ulcer is felt with button like depression, induration and often sentinel pile.
The lower end of the fissure can be seen by gently parting the margins of anus.
Digital examination and proctoscopy is not possible in acute fissure in ano.

Anal fissure

Sentinel pile

Differential Dx

Treatment

Conservative t/t

NO- neurotransmitter that induces relaxation of the internal spchicter.
Glyceryl trinitrate- being nitric acid donor, when applied as an ointment causes relaxation of the sphincter and also improves blood flow- both aids healing.
Use of laxatives and xylocaine surface anaesthetic.

Surgical

Gentle dilatation of the sphincter under GA:

Can be used in young men with high pressure sphincter.
CI in pts. with weak sphincter.
If this method is ineffective or if the fissure is chronic with fibrosis, a skin tag or a mucus polyp, then surgery is done under GA(best) or LA.

Lateral anal sphincterotomy:

Here internal sphincter is divided away from the fissure either in right or left lateral positions.
Can be done in OPD basis under L/A.
Healing completes in 3 wks.
Good result for acute than chronic cases.
Small risk of incontinence.

Closed and open

Anal advancement flap:

Here excision of the edges of the fissure and mobilization of a square, full-thickness anal skin flap which is slided forward over the fissure and sutured in place.
Only little risk of damage to the underlying internal sphincter and incontinence is unlikely.

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