Potential acuity meter (PAM) measurement
Potential acuity meter (PAM) is a simple visual test used on patients suspected of having some visual difficulty due to a probable problem in the front portion of the eye. This test is used most often in this office to determine what part of a patient’s visual loss is due to retinal disease and what part is due to abnormalities of the front of the eye, such as cataract.
During this procedure, a tiny beam of light is directed through the patient’s pupil onto the retina. This light beam actually contains a visual acuity chart with letters for the patient to read. Patients simply read the chart to the best of their ability, just as they would with the more familiar visual acuity wall chart.