This study examines normal tension glaucoma, which is a type of eye disease where the nerve that carries visual information from the eye to the brain becomes damaged even though the pressure inside the eye is not elevated. In this condition, the field of vision gradually becomes smaller, and the layer of nerve fibers at the back of the eye becomes thinner over time. The study will use Ismox 20 mg tablets, which contain the active ingredient isosorbide 5 mononitrate, a medication that belongs to a group of medicines called nitrates that help improve blood flow. This medication will be given in addition to the regular eye drops that patients are already using for their glaucoma treatment. Some participants will receive a placebo instead of the active medication.
The purpose of the study is to find out whether taking this long-acting nitrate medication by mouth can improve blood circulation to the optic nerve head, which is the part of the nerve at the back of the eye where damage occurs in glaucoma, and whether it can help slow down the progression of the disease when used together with other glaucoma treatments. The study will also examine how the medication affects the structure and function of the eye using various imaging and testing methods.
During the study, participants will attend regular visits where the thickness of the nerve fiber layer at the back of the eye will be measured using a special imaging technique called optical coherence tomography, which uses light waves to take detailed pictures of the eye structures. Visual field testing will also be performed to measure how well participants can see in different areas of their vision. The study will last for 18 months, with measurements taken at the beginning and at 6, 12, and 18 months to track any changes over time. The main focus will be on measuring changes in nerve fiber thickness and visual field measurements to determine whether the medication helps slow down disease progression compared to placebo.
Finland 
