Fistula in Ano general surgery presentation

fistula in ano for pg

1. Management of Fistula in Ano Dr Navdeep Kaur Junior Resident Dr RPGMC, Tanda Dr Vikrant Sharma Assistant Professor Dr RPGMC, Tanda

2. References Sabiston Textbook of Surgery Bailey and Love Textbook of Surgery Fischer's Mastery of Surgery S Das : Manual on Clinical Surgery

3. Fistula-in- ano results from persistent communication between the anal canal (internal opening) and perianal skin (external opening) following spontaneous or surgical drainage of a perianal abscess

4. Anatomy

5. The anal canal is approximately 4 cm in length, extending from the anal verge to the anorectal ring. The proximal anal canal is typically lined by columnar epithelium and the distal anus by squamous epithelium. The junction between the ectoderm and the endoderm, appears as an undulating demarcation referred as dentate line

6. The dentate line consist of row of alternating columns and crypts which contains anal glands The anal gland duct traverses the submucosal plane and its branches terminate within the internal anal sphincter or extend into the intersphincteric plane. Foreign debris may obstruct the ducts and result in the common perianal abscess, and its chronic counterpart, the fistula-in- ano

7. T he internal anal sphincter is a thickened continuation of the circular layer of the muscularis propria of the distal rectum and occupies the distal 2 to 4 cm of the anal canal. The external anal sphincter is a funnel shaped structure composed of the pelvic floor muscles enveloping the distal rectum and anus. The puborectalis muscle, often referred to as the rectal sling, is one of the main muscles contributing to the external anal sphincter. It originates at the pubis, passes around the rectum posteriorly, and returns to the pubis.

8. Etiology of anorectal abscess Nonspecific etiology Cryptoglandular Specific etiology Inflammatory condition Crohn disease Tuberculosis Actinomycosis Lymphogranuloma venereum Traumatic etiology Impalement Foreign body Anal fissure Iatrogenic Episiotomy Hemorrhoidectomy Prostatectomy Radiation Malignancy Rectal or anal carcinoma Leukemia Lymphoma

9. Pathophysiology Perianal abscesses typically result from infection of the anal glands located at the level of dentate line and are attributed to obstruction of the draining duct from fecal debris; this is often referred to as a cryptoglandular abscess that develop in the intersphincteric space. Fistula-in- ano results following spontaneous or surgical drainage of a perianal abscess

10. Risk Factor Previous perianal abscess formation Crohn's disease Diabetes Mellitus Tuberculosis Lymphogranuloma venerum Actinomycosis Rectal duplication Trauma Radiotherapy Immunocompromised pts (HIV infection, malignancy)

11. Classification Fistula-in- ano can be classified as: Based on the centrality of intersphincteric anal gland sepsis and relation of primary track with external sphincter defines the type of fistula and which influences management Parks classification I ntersphincteric : (45%) do not cross the external sphincter Trans sphincteric: (40%) have a primary track that crosses both internal and external sphincters Suprasphincteric: rare) runs above external anal spinchinter Extra sphincteric : run without specific relation to the sphincters, usually result from pelvic disease or trauma.

12. Classifications based simply on level of a fistula as high, indicating a high risk of incontinence if laid open, or low, with a lower but still some risk to function, is often used. Similarly, ‘simple’ and ‘complex’ are commonly used adjectives

13. SIMPLE FISTULA superficial/low inter or transsphincteric tract, single external opening COMPLEX FISTULA high inter or transsphincteric tract,extra or suprasphincteric tract,presence of abscess or collection,anovaginal fistula, anal stricture

14. Clinical presentations Patients often report a cyclical pattern of pain and swelling, followed by drainage associated with relief of the symptoms Perianal discharge Perianal pain Swelling and lump in perianal area External opening in perianal area Fever Multiple external openings or so called water can perineum

15. Examination The key points to determine are The site of the internal opening; T he site of the external opening(s); T he course of the primary track; T he presence of secondary extension .

16. Goodsall’s rule When the external opening of a fistula-in- ano lies behind the transverse line passing across the anus or anterior to this line but beyond one and half inches from the anus, the internal opening is found in the midline posteriorly between the sphincters, the fistula’s track being curved. When the external opening is situated in front of the transverse line, but within one and half inches from the anus, the internal opening lies in the same radial line as the external orifice, the fistula track being straight

17. Investigation Endoanal ultrasound MRI is the ‘gold standard’ for fistula imaging. A dvantage of MRI is its ability to demonstrate secondary extensions, which may be missed at surgery and which are the cause of persistence Fistulography

18. Surgical Management Fistulotomy: The principle of fistulotomy is the identification of the fistula track so that the track can be laid open. This method of treatment is inappropriate for patients with extrasphincteric and suprasphincteric fistula as any lay-open procedure divides the striated sphincter complex and renders the patient incontinent

19. A malleable fistula probe is gently passed through the fistula tract and all the tissues between exrenal and internal opening are divided If a substantial amount of striated muscle is encountered superficial to the fistula track, division of the muscle is not advisable and a seton is inserted

20. Seton Fistulotomy A vascular rubber sling (loop) is threaded through the eye of the fistula probe and is delivered around the striated muscle as a seton The seton is tied with multiple knots, and the end is sutured beyond the last knot

21. Fistulectomy and Anorectal Advancement Flap The first part of the operation involves fistulectomy, that is, excision of the fistula track. The next step is to close the internal opening, usually with an anorectal advancement flap. A wide-based curvilinear flap, consisting of mucosa, submucosa, and rectal wall, is advanced from above so as to close the internal component of the fistula without tension

22. Complete Lay Open and Repair Extrasphincteric and suprasphincteric fistulae may be treated by total fistulotomy while ensuring that the divided and striated muscle is marked so that it can be identified at a later date. Once all of the infection has been cleared, a standard sphincter repair is then performed. The alternative is to perform the reconstruction at the time of the primary lay-open procedure

23. Anal Plug : The principle of this is to preserve anal sphincter function with the avoidance of a gutter by filling the fistula track with a rod of fibrin, which enhances fibroblastic activity thereby eliminating the fistula track by forming a collagen matrix in the fistula. Surgical technique involves identification of the fistula, which is then gently curetted with a line wire brush or an equivalent bougie to remove the granulation tissue. After irrigation of the fistula, the plug is inserted and sutured into position in the anal canal.

24. Ligation of intersphincteric fistula tract (LIFT) The technique involves ligation and division of the fistula tract at the level of the intersphincteric plane and removal of the residual infected glands without diving any part of the sphincter complex

25. THANK YOU Created by Dr Darshan A N