As you probably know, glaucoma results from a build up of pressure inside the eye which can lead to damage to the optic nerve over time. There are two types of glaucoma. The first is called angle closure glaucoma, in which the channel that drains the fluid from the eye becomes closed off, leading to a buildup in pressure. This often requires surgery
to relieve the obstruction, and this may be the type of glaucoma that you have. In followup, the main thing will be to measure the pressure inside the eye, making sure you are taking any medications that you were prescribed, and to look for any signs of scarring or return of the blockage. This would be the main indication for repeating the surgery.
The other type of glaucoma, called open angle glaucoma, also results in a build up of pressure in the eye, but it is less related to blockage of fluid outflow. Therefore, it tends to be more managed with eye drops and oral medications to control the pressure. Followup, therefore, is about making sure you are taking the medicines, looking for side effects, and measuring the eye pressure.
In both types of glaucoma, of course the visual acuity is also closely assessed at each followup.