Influence of refractive state on mesopic/scotopic pupil diameter and anisocoria.

Abstract

PURPOSE: To stablish the effect of the refractive state of a subject on pupil diameter and anisocoria in mesopic and scotopic conditions. METHODS: A prospective evaluation was performed of the pupil size and refractive state of 68 subjects aged 16 to 56 years ( 24.27 +-6.2 years) free of any eye pathology. Measurements were obtained using the ifrared, binocular pupillometer P2000 (Procyon Instruments Ltd) after a 5 min period of adaptation to mesopic condition ( 3cd/m2). Determinations were made at three luminance levels: 0.04 lux (scotopic), 0.4 lux ( low mesopic) and 4 lux (high mesopic). For each measurement, 10 photographs of both pupils were automatically taken. Refractive error were determined using the Nidek mod.700 autorefractometer. Subjects were classified according to their refractive state as: emmetropes (+0.50D to -0.50D), myopes (from -0.75D) and hypermetropes (from +0.75D)