Aim: To compare the effectiveness of local glyceryl trinitrate (GTN) versus internal sphincterotomy in the 
management chronic anal fissure. 
Methods: Eighty patients with chronic anal fissure were enrolled in the study. They were divided into two 
groups; group (1) included 40 patients treated with topical GTN 0.2% on liposomal base applied to the 
anoderm twice daily and group (2) included 40 patients treated with internal sphincterotomy. We compared 
the effectiveness of both techniques in the management chronic anal fissure 
Results: In group 1, healing of fissures occurred in 85% of patients after 8 weeks therapy. Headache as a side 
effect developed in 65% of patients. In group 2, healing occurred in 97.5% of patients after 8 weeks. 
Incontinence to flatus occurred in 3 patients (7.5%), mild soiling in 2 patients (5%) and one patient developed 
wound infection. All complications were temporary except for one patient with persistent incontinence to 
flatus. At the end of 8 weeks both groups were equal in pain scoring. 
Conclusion: Topical GTN should be the initial treatment in chronic anal fissure while internal 
sphincterotomy may be reserved for patients who not respond to GTN therapy and those with severe pain 
(as healing is faster with sphincterotomy).