Quantitative measurement of corneal haze after myopic PRK

OBJECTIVE: To design and evaluate an instrument for the objective measurement of haze in rabbits after myopic PRK. METHODS: A circular fluorescent lamp bulb projected light onto the cornea through a circular collimating aperture covered with an orange filter. The image was collected on a centrally mounted CCD camera and the profile of the haze circle along its horizontal diameter determined. RESULTS: Haze circles were observed and quantitated. In the first weeks, they were donut-shaped, frequently with a central bright area, but later they became square-topped. The instrument reproduced measurements with an error of a few percentage points and showed good long-term stability. [J Refract Surg. 1996;12:412-416.]