Evaluation of pupil dynamics after implantation of artisan phakic intraocular lenses.

PURPOSE To compare pre- and postoperative horizontal and vertical pupil diameters after horizontal Artisan phakic intraocular lens (PIOL) (Ophtec BV, Groningen, The Netherlands) implantation for correction of myopia. METHODS The pre- and postoperative scotopic pupil diameters measured by the Colvard pupillometer (Oasis Medical, Glendora, Calif) were compared in 71 eyes after Artisan PIOL implantation (Artisan Colvard group). Analysis of pupil shape (vertical vs horizontal diameter, V/H ratio) after horizontal Artisan PIOL implantation was performed with the Procyon pupillometer (Procyon Instruments Ltd, London, United Kingdom) in 121 eyes (Artisan Procyon group) under scotopic, mesopic-low, and mesopic-high conditions and compared to an age- and refraction-matched control group of 121 eyes of refractive surgery candidates (Procyon control group). RESULTS After horizontal Artisan PIOL implantation, the mean horizontal pupil diameter decreased from 6.231 +/- 0.70 mm preoperatively to 5.34 +/- 0.68 mm postoperatively in the Artisan Colvard group (P < .01). The mean horizontal scotopic diameter was 5.60 +/- 0.66 mm, the mesopic-low diameter was 4.94 +/- 0.71 mm, and the mesopic-high diameter was 3.98 +/- 0.54 mm for the Artisan Procyon group. The mean horizontal scotopic diameter was 6.29 +/- 0.91 mm, the mesopic-low diameter was 5.40 +/- 0.96 mm, and the mesopic-high diameter was 4.16 +/- 0.80 mm in the Procyon control group. A significant increase was noted in V/H ratio under scotopic, mesopic-low, and mesopic-high conditions from 1.02, 1.02, and 1.01, respectively, in the Procyon control group to 1.17, 1.12, and 1.06, respectively, in the Artisan Procyon group (P < .01). CONCLUSIONS Horizontal pupil size was significantly decreased after horizontal Artisan PIOL implantation and might be attributed to a mechanical restriction of the iris in the horizontal meridian.