What is the field of vision threshold and what does it have to do with glaucoma?

Question

I thought the puff of air was the test for glaucoma.

Answer 1

I believe you are talking about visual field testing which is often done on patients to determine if there has been any loss in photoreceptors due to glaucoma. This helps track the progress of the disease and to help make sure the medication is doing its job in slowing the progression. The threshold is how sensitive you are to the stimuli being presented in the visual field test.
The puff of air is used to get an estimate of the pressure inside the eye. An increased pressure raises the chances of photoreceptor death. This is simply a screening test as there are other factors that play a role in the diagnosis of glaucoma. it gives the doctor an indication that something might be happening that needs to be more closely examined.