The Arden gratings in optometric practice.

The use of the Arden gratings (AO contrast sensitivity system) in optometric practice is evaluated. A total of 320 patients presenting for eye examination were screened with the gratings. Sixty-four eyes (10%) gave abnormal grating scores although results from conventional examination techniques revealed no abnormality. Of the 110 abnormal eyes detected by routine examination techniques, 8 presented with normal grating scores, 6 with "borderline suspect" scores and 96 with abnormal scores. Used in isolation, the failure rate of the Arden gratings to detect ocular abnormality in the patient population was 1.3% and the "false positive" referral rate was 10%.