1. The Best Surgical Treatment for Fistula-in-ano
Dr John Wong
PYNEH

2. Etiology Cryptoglandular theory Trauma Foreign body Iatrogenic
Malignancy
Crohn’s disease
Tuberculosis
HIV
Suspected secondary cause:
Known Hx of crohn, TB
Proctitis
Complex fistula (recurrent after adequate Tx, multiple track, high fistula)
J.G.Williams et al. Colorectal Disease 2007

3. Classification Park’s classification (1976)
Inter-sphincteric (~45%)
Trans-sphincteric (~30%)
Supra-sphincteric (~20%)
Extra-sphincteric (~5%)
J.G.Williams et al. Colorectal Disease 2007

4. Goodsall’s rule 49% 90% J.G.Williams et al. Colorectal Disease 2007
Exception:
Horseshoe fistula
Long track that extend to the anterior quadrant of the anal canal
Crohn’s
Iatrogenic
90%
J.G.Williams et al. Colorectal Disease 2007

5. Investigation

6. Investigation Indications: Complex fistula Impaired sphincter function
Suspicious of secondary cause

7. Investigation Anatomy Physiology Cause Endoanal Ultrasound, MRI
Anorectal manometry
Cause
Inflammatory marker, colonoscopy, rectal biopsy

8. Endoanal Ultrasound
High accuracy (93%) to identify the internal opening
Injection of hydrogen peroxide can increase the detection rate
3 criteria for identification of internal opening by USG - contact of the sphincter by the intersphincteric track
Apparent defect of the internal sphincter
A defined subepithelial track associated with a localized sphincter defect
7-10 MHz
ANZ J. Surg. 2005; 75: 64-72
J.G.Williams et al. Colorectal Disease 2007

9. Endoanal Ultrasound Disadvantage:
Pain and discomfort
Operator dependent
Limit field ~2cm from probe
Limited use for trans-sphincteric or more complex FIA!
High frequency probe -> limited fied
Not for trans-sphincteric fistula

10. MRI Gold standard Multi-planar image
Show the fistula system in relation to the underlying anatomy
High sensitivity
Primary track: 86%
Secondary track: 91%
Horseshoe extesion 97%
ANZ J. Surg. 2005; 75: 64-72
J.G.Williams et al. Colorectal Disease 2007

11. Treatment

12. Principles of management
To drain abscess
To deal with the secondary track if any
Definitive treatment of the primary track
Efficacy Continence

13. Fistulotomy
Lay-opening of the fistula track from external opening to internal opening
Inter-sphincteric fistula
Recurrence rate 0-21%
Disturbance in continence: 0 to 82%
Extent of external sphincter division: <30%
Other risks factor for incontinence
Females, anterior fistula, association with Crohn’s disease and prior fistula surgery
J.G.Williams et al. Colorectal Disease 2007

14. Fistulectomy Excision of the entire fistula track Low lying fistula
No advantage in both recurrence and incontinence rate compared with fistulotomy
High lying fistula
‘Core out’ technique + internal sphincterotomy
For patho assessment
Excision of the extra-sphincteric part of the trans-sphincteric fistula
Surgical intervention for anorectal fistula. The Cochrane Collaboration 2010

15. Fistulectomy + Internal Sphincterotomy

16. Seton Loose seton Achieve drainage of the fistula track
Allow any secondary track to heal
As part of staged fistulotomy
J.G.Williams et al. Colorectal Disease 2007

17. Staged fistulotomy Low recurrence rate
Significant rate in incontinence
Major incontinence rate up to 42%
J.G.Williams et al. Colorectal Disease 2007

18. Seton Tight (cutting) seton
Commonly used in high transphincteric fistula
Divide the muscle slowly to produce a gradual fistulotomy
Recurrence rate 0-18%
Disturbance of fine control is common
Major incontinence rate ~10%
J.G.Williams et al. Colorectal Disease 2007

19. Disturbance of fine control is common
Low recurrence rate
Disturbance of fine control is common
Major incontinence rate >10% (up to 43%)
Recurrence rate 0-18%
Disturbance of fine control is common
Major incontinence rate ~10%
J.G.Williams et al. Colorectal Disease 2007

20. Fibrin Glue Fibrin clot to seal the track
Stimulate the migration, proliferation and activation of the fibroblasts
Sphincter-sparing method
Activated mixture of fibrinogen, factor XIII,
fibronectin & aprotinin
(Tisseel, Viguard and Beriplast)
A.I. Malik & R.L. Nelson; Colorectal Disease 2008

21. Fibrin Glue High recurrence rate Long term healing rate(~14% - 60%)
A.I. Malik & R.L. Nelson; Colorectal Disease 2008

22. Anal Fistula Plug Sphincter-sparing method Bioprosthetic plug
Internal opening must be identified
Initally rehydrated for 1-2min
Plug pull through the track from the internal opening
Sutured in the int opening
Ext opening lay open
Excessive plug cut
Advise to avoid heavy lifting / straining for 2wk

23. Anal Fistula Plug Controversial results from different centre
Low success rate
Controversial results from different centre(14%-87%)
Shawki S et al. World Journal of Gastroenterology 2011
P. Garg et al. Colorectal Disease 2010
PYNEH %
P. Garg et al. Colorectal Disease 2010
HYS Cheung et al. Surgical Practice 2009

24. Advancement Flap + core out fistulectomy
Sphincter-sparing method
Pre-op bowel prep and antibiotics cover
Internal opening must be identified
+/- temporary diverting stoma
U-shaped muco-muscular flap
Fistula track is cored out
Closure of the internal defect
Suture the flap with absorbable stitches
Ext opening lay open

25. Advancement Flap + core out fistulectomy
Low long term success rate
~ 13%-56%
High recurrence due to:
Small flap
Excessive tension
Low long term success rate
High recurrence due to:
Small flap
Excessive tension
J.G.Williams et al. Colorectal Disease 2007

26. LIFT
Ligation of Intersphincteric Fistula Tract
Rojanasakul in 2007

27. LIFT Short term success rate was encouraging (~57-94%)
Long term result still unknown
Arch Surg. 2011;146(9):

28. Conclusion No single best treatment for FIA
Treatment for FIA must be individualized
Types of the fistula
Premorbid sphincter function

29. Recommendation Fistulotomy
Inter-sphincteric fistula (High / low lying, with or without internal opening)
Fistulotomy

30. Trans-sphincteric / Supra-sphincteric fistula
No internal opening
Fibrin Glue
Core out fistulectomy + exploration of inter-sphincteric plane +/- internal sphincterotomy

31. Trans-sphincteric / Supra-sphincteric fistula
With internal opening
High risk of incontinence
AFP
Advancement Flap
Core out fistulectomy + internal sphincterotomy
Cutting seton / Staged Fistulotomy
Low risk of incontinence

32. Recommendation Extra-sphincteric fistula
Usually associated with an underlying cause
Treat the underlying cause
Drain any sepsis
Never disrupt or explore the sphincter

33. Thank you!

34. Exception for Goodsall’s rule
Horseshoe fistula
Long track that extend to the anterior quadrant of the anal canal
Crohn’s disease
Iatrogenic

35. Fistulogram Accuracy ~16-50% only
Difficult to relate the track to the sphincter anatomy
The acute track are just column of granulation tissue without a lumen
Need external opening
Painful

36. Fistulotomy in acute anorectal sepsis
Pros:
decrease the rate of recurrent anorectal sepsis
Cons:
increase risk of impair continence
Some individuals would have unnecessary surgery
Fisulotomy should be performed when internal opening can be found and the fistula is submucosal or intersphincteric (low lying)
J.G.Williams et al. Colorectal Disease 2007

37. Radiofrequency fistulotomy
Use of radio-wave as energy source
Less bleeding
Less pain
Quicker recovery
No difference in recurrence and incontinence rate
Surgical intervention for anorectal fistula. The Cochrane Collaboration 2010

38. Fistulotomy with marsupialization
Suturing the edge of the track to its base
Less bleeding
Shorter healing time
No difference in recurrence and incontinence rate
Surgical intervention for anorectal fistula. The Cochrane Collaboration 2010

39. Fistulotomy vs Fistulectomy
No difference in recurrence and incontinence rate
A.I. Malik & R.L. Nelson; Colorectal Disease 2008

40. Chemical seton Coated with layers of latex and plant extracts
Strong alkaline outer layer
Cut through tissue at a rate of 1cm every 6 days
More painful
Evidence on recurrence and healing rate remain inconclusive
A.I. Malik & R.L. Nelson; Colorectal Disease 2008

41. Anal fistula plug Better outcome in : Deep trans-sphincteric fistula
Long track fistula
Narrow-gauge fistula

42. Advancement Flap Contra-indications: Presence of proctitis
Undrained sepsis
Malignant / radiation related fistula
Stricture of the anorectum
Severe sphincter defect
Severe peripheral scaring due to previous surgery
J.G.Williams et al. Colorectal Disease 2007

43. FIA with Crohn’s disease
Medical treatment, eg. Anti TNF-alpha
Infliximab
Emergency treatment
Incision and drainage of the fistula
Stabilization
Insertion of seton to optimize drainage and medical therpay
J.G.Williams et al. Colorectal Disease 2007

44. Incontinence scale Flatus, mucus, liguid, solid stool
The Cleveland Clinic (Wexner) Incontinence Score
sum of 5 parameters is on a scale from 0 (=absent) to 4 (daily) frequency of incontinence to gas, liquid, solid, of need to wear pad, and of lifestyle changes.