There are other tests that are sometimes used for glaucoma patients mentioned throughout this guide.

Pachymetry: the measurement of central corneal thickness, using an ultrasonic probe held against the cornea with eye drop anesthesia. The importance of corneal thickness in measuring eye pressure and as a separate contributing factor to glaucoma is mentioned above in this section and in How did you get glaucoma?

Visual acuity measurement: letters read on a chart projected on the wall from big ones down to little ones, showing how good the center vision is. Sometimes a set of holes is placed in front of the eye to read the acuity chart. If the vision is better looking through one of the holes, this means that new eyeglasses would help the patient see better (called pinhole vision).

Ultrasonic biomicroscopy and anterior segment optical coherence tomography: instruments that show detail of the structures in the front of the eye and give information about movement of aqueous humor (see section Why isn’t glaucoma either there or not there? - What makes you an angle closure suspect?).

Afferent pupil response: The doctor shines a light on one eye then on the other. How the pupil responds as the light swings back and forth can tell that one eye’s optic nerve is damaged more than the other.