gms | German Medical Science

Background: The aim of this study was to evaluate the influence of cataract surgery on pupil size at well defined measurement conditions with a novel pupillometer (PupilX).

Methods: Pupil size of healthy study participants was measured with infrared-video PupilX pupillometer (MEye Tech GmbH) at 5 different illumination levels (0, 0.5, 4, 32 and 250 lux) before and after cataract surgery. Measurements were performed by the same person during a measurement period of 3 seconds with 90 images and an absolute linear camera resolution of approximately 20 pixel per mm.

Results: This prospective study analysed the pupil size of 35 patients (mean age 73.2 ± 8.6 years, range 50-87 years). One week after cataract surgery mean pupil diameter for all patients decreased ignificantly by -13.1 % at 0 Lux, -13.6% at 0.5 Lux, -8.4% at 4 Lux, -7.3% at 32 Lux and -5.1% at 250 Lux. Beside the gradually decreasing pupil size with an increasing illumination level there is a significant decreased pupil size after cataract surgery at all illumination levels.

Conclusion: In conclusion, this study showed a significant decrease of pupil size after cataract surgery in a normal population under scotopic, mesopic and photopic static illuminance conditions. The precision of measurements and variability of illuminance conditions of PupilX (MEye Tech GmbH) allows the possibility of investigations of pupil size in relation to refractive surgery.