Prognosis of pseudophakic retinal detachment

Reply: We would like to thank Cheng et al. for their comments. The Zywave unit used by them (commercial software 5.09) is different from the one used in our study (software 4.45SP2). Using the pupillometry function, software 5.09 has no fixation target light and the infrared laser runs continuously at 2 mW of power during the measurement. Software 4.45SP2 has no fixation target light, and the infrared laser runs continuously at 2 mW and then at 35 mW for 100 ms during each measurement. In our study, the measurement was the diameter of 3 averaged wavefront readings. However, even in the continuously running setup of the commercial system, there is variation in pupil size due to hippus that is on the order of the changes in pupil size one sees between the 3 measurements. Variations from day to day may be larger than the differences Cheng et al. are questioning in our measurements. It might be correct to use the largest recorded pupil size rather than an average for a better representation of the scotopic pupil size, but in the study mentioned by Cheng et al., the averaged Zywave measurement is compared with the scotopic Procyon measurement, which in itself represents the mean and standard error of 10 images acquired in 2 seconds at an illuminance level of 0.07 lux.dThomas Kohnen, MD, Evdoxia Terzi, MD, Thomas Kasper, MD, Eva-Maria Kohnen, MD, Jens Bühren, MD