Testing visual function in the clinical setting

The explosive growth of automatic examination of the eye, in particular for determining refractive corrections, invites an analysis of the strengths and limitations of these devices and their role in clinical decisions. Subjective refraction procedures are based on a patient's visual responses and these embrace many levels of additional optical and neural processing and factors involving the higher-order nervous system and perception. Because the ultimate mission is the maintenance and improvement of a patient's visual experiences, the optometric examination necessarily extends beyond the employment of automatic devices and therefore, should include engaging the patients in tests of their visual functions.