Fistula

Question 1

Parks classification of FIA

Answer 1

I: intersphincteric
II: transphincteric
III: suprasphincteric
IV: extrasphincteric

Superficial fistula

Question 2

Pathophysiology of fistula in ano

Answer 2

Cryptoglandular hypothesis:
infected anal glands in the intersphincteric space leading to abscess which takes the path of least resistance to form fistula

Question 3

Goodsall Rule

Answer 3

Position of internal opening

• If EO within 3cm of anal verge lies anterior to a line drawn between 3oc and 9 oc, it usually run a direct tract into anal canal
• If EO within 3 cm of anal verge is posterior, the tract usually curve to the posterior midline of anal canal

Question 4

Management principles

Answer 4

Drain any septic component
Rule out secondary causes
Define anatomy of fistula tract
Eradicate fistula tract and prevent recurrence
Preserve continence and sphincter function

Question 5

Secondary causes of FIA

Answer 5

TB
Malignancy
Crohns
RT
AIDS
Diverticular disease

Question 6

Fistulotomy vs fistulectomy

Answer 6

Fistulotomy
-faster healing time
-lower incidence of incontinence
-similar recurrence
Drawback: no tissue for histology

Question 7

Surgical procedures for FIA

Answer 7

Fistulotomy
Fistulectomy
Cutting seton
LIFT
Anorectal flap
Fibrin glue/biological plug

Question 8

What is LIFT?

Answer 8

Ligation of Intersphincteric Tract

• sphincter sparing technique
• ligation of fistula tract in intersphincter groove

Question 9

Definition of complex fistulas

Answer 9

fistulas with high risk fo treatment failure, cannot be safely done with routine fistulotomy

Question 10

Examples of complex fistula

Answer 10

• involving > 30% of external sphincter
• multiple tracts
• recurrent fistulas
• suprasphincter / extrasphincter
• women with anterior fistulas
• due to secondary causes
• patient with history of anal incontinence
• rectovaginal fistulas

Question 11

Definition of high type FIA

Answer 11

Internal orifice begins above the puborectalis and tract pass through a good bulk of muscle fibers

Milligan and Morgan classification

Question 12

Definition of low type FIA

Answer 12

Internal orifice begins below the puborectalis and tends to pass through few or no muscle fibers

Milligan and Morgan

Question 13

Management for simple FIA

Answer 13

Fistulotomy

Question 14

Management for complex FIA

Answer 14

Draining seton +

• conversion fistulotomy by cutting seton
• endoanal/ endorectal advancement flap
• LIFT
• Modified Hanley procedure
• Fibrin sealant
• Fibrin plug
• Diversion stoma

Question 15

Postoperative Management

Answer 15

• High fiber diet
• Adequate hydration
• Hygiene
• Ensure adequate bowel opening