by thisfissurecankissmybutt » 22 Aug 2012, 17:21
GTN = Glyceryl Trinitrate, which is an alternative name for the chemical Nitroglycerin (which helps relax your sphincter so that it can allow the fissure to heal). In my experience, Nitrofedipine is much better with less side effects (GTN can give you severe headaches).
LIS = Lateral Internal Sphincterotomy, which is a minor operation which can be carried out under either local or general anaesthesia. Basically, a scalpel is used to cut the internal sphincter which will lower the resting pressure of the sphincter without destroying the effect of the sphincter, allowing the fissure to heal.
I hope this helps.