Validity of the laser refraction technique for determining cylindrical error

Employing a laser refraction technique, spherical error was determined for each of three meridans in 50 eyes. The measurements were used to calculate spherical error and cylindrical axis and power, and the findings were compared with standard methods of measurement. Correlations between the laser and non-laser methods indicated that the laser technique is a valid method for determining spherical error. Correlations between the findings for laser and non-laser cylindrical measurements were not high enough to warrant use of this laser technique in clinical practice. Differential laser validity findings for against-the-rule astigmatism are also discussed.