Current Management of Chronic Anal Fissure Joint Hospital Grand Round Department of Surgery,North District Hos pital and Alice Ho Mui Ling Nethersole Ho spital, NTEC Anal Fissure Definition: An elongated ulcer in the long axis of lower
anal canal Pathology A split of anoderm Associated with anal skin tag and hypertr ophied anal papilla Occur at midline just distal to dentate lin e 90% posterior, 10% anterior with less tha n 1% simultaneous Presenting Sym.
Pain Bleeding Discharge Constipation Examination Gentle eversion of anus with limited digit al examination Anoscopy and rigid sigmoidoscopy unde r anaesthesia or deferred till healing occ ur
Anomanometry is not useful Differential Dx. Fissure occurs out of midline 1. 2. 3. 4.
Carcinoma of anus Inflammatory bowels Tuberculous ulcer HIV/Herpes Biopsy should be taken for ulcer out of mid line or those fail to heal Anorectal Physiology Continence is maintained when intrarect al pressure are lower then the pressure generated by the resting internal and ext
ernal sphincters. Anorectal Physiology Internal Sphincter: Smooth muscle Innervated by sympathetic (excitatory) and parasympathetic fibre; (inhibitory)
Constant contraction 85% of resting tone Pathophysiology Forceful dilatation Split of anoderm Fail to relax when BO Sphincter spasm
ischemia Fail to heal Pathophysiology Great pain associated with initial bowel motion Patient ignores the urge to defecate Allows harder stool to form Self-perpetuating cycle Management
good bowel habit Relieve internal anal sphincter spasm Management Conservative: to regulate bowel habit, br eak the self-perpetuating cycle Stool softener Bulk forming agent
Sitz-bath 90% healing rate (1 st epsiode) 60% healing rate for recurrent Management Sphincterotomy to break the vicious cycle induced sphinct er spasm
to reduce anoderm ischemia and to promo te healing Management Conventional surgical sphincterotomy ve rsus chemical sphincterotomy Surgical sphincterotomy Lateral internal anal sphincterotomy 1.
Open v.s. Close Fissurectomy with anoplasty: reserved for case s with prominent skin tag/recurrent anal fissure 2. Longer healing time
Results and complication Open Close P value Persistence 3.4% 5.3%
0.27 Recurrence 10.9% 11.7% 0.77 reoperation 3.4%
4% 0.70 Lack of control 30.3% of gas 23.6% 0.06 Soiling
26.7% 16.1% <0.001 Accidental BM 11.8% 3.1%
<0.001 Surgery good healing rate but rather high complication Alternatives? Sphincterotomy-chemical Chemical sphincterotomy Nitrogylcerin ointment
Botulinum toxin injection Ca channel blocker/steriod Nitrogylcerin ointment As a source of nitric oxide Inhibitory neurotransmitter cause internal anal sphincter relaxation
Commonly used 0.2-0.3% nitroglycerin Local application by patient twice daily for 6/52 Result Healing rate :60-75% Side effect: 15-40% headache Result N=44 0.2% isosorbide
dinitrate surgery 5 weeks healing rate 67% 96% 10 weeks healing rate
89% 100% 30% decrease of maximal anal pressure in both arms side effect 30% headache 15% incontinence Parellada C et al. Randomized, prospective trial comparing 0.2 percent isosorbide dinitrat
e ointment with sphincterotomy in treatment of chronic anal fissure; a two years follow-up. Dis Colon rectum. 2004 ;47(4) 437-43 Botulinum Toxin Mechanism of action: Action on internal anal sphincter as shown in manometric studies( reducing both the r
esting and squeezing pressure) Exact mechanism uncertain; inhibit acetylc holine release into synaptic gap causing ne uormuscular blockade More sustained action then Nitroglycerin oi ntment How to inject? Botulinum toxin A Target: internal anal sphincter as palpate d No local anesthetic nor sedation required
How to inject? at least 15 unit ? Probably better in multiple punture Minguez M et al. Theraputic effects of different doses of botulinum toxin in chronic anal fissue Dis Colon Rectum. 1999 Aug;42(8):1016-21 Where to inject? anterior injection of the internal anal sph incter resulted in improved lowering of re
sting anal pressure and produced an earl ier healing Maria G et al. Influence of botulinum toxin sit e on healing rate in patients with chronic ana l fissure. Am J Surg. 2000; 179(1):46-50. Result: Fissure healing rate: 70-90% at 2 months Recurrence/non healing: 20%
No major side effect; Giuseppe Brisinda and Maria G et al. A comparison of botulinum toxin a nd topical nitroglycerin ointment for the treatment of chronic anal f issure N Engl J Med1999;341(2): 65-68 Result RCT comparing comparing Botulinum vs
Nitroglycerin ointment N=50 Higher fissure healing rate at 8 weeks in Botox group 96% vs 60% Significant lower resting anal pressure in Botox group B.Bulent Mentes et al. Comparison of Botulinum toxin injec tion and lateral internal sphincteroto my for the treatment of chronic anal f issure
Dis Colon Rectum 2002. 46(2) 232-37 N=111 Surgery Botox Fissure healing 82% rate at 2 months 73.8%
At 6 months 98% 86.9% recurrent 0 11.4%
Return of daily activities 14.8 days 1 day complication 16% 0
Conclusion: Internal anal sphincter spasm is the key to tackle chronic anal fissure Traditional lateral sphincterotomy give ex cellent result in terms of fissure healing b ut bearing significant risk of incontinence Conclusion Result of chemical sphincterotomy is sat isfactory, without the complication of late
ral sphincterotomy and should be consid er the first line treatment. Botox injection give the most reliable res ult among different methods of chemical sphincterotomy
