Abstract
Purpose :
With a population incidence varying between 0.20% for severe cases and 25% for mild to moderate ones, negative dysphotopsia (ND) is associated with the perception of dark crescent shadows in the peripheral field of view (PFoV) of pseudophakic patients. As contributing factors, literature reviews enumerate biometry (pupil size in photopic conditions, angle kappa, hyperopia etc) and intraocular lens characteristics (IOL, tilt and decentration, optic body size etc). Building on our previously communicated results, the current study evaluates the predictive ability of personalized theoretical eye models to localize the ND in PFoV.
Methods :
In a prospective study conducted at Hanusch Hospital, Vienna, Austria, post-operative biometrical data sets (pupil size, ACD and AL, anterior corneal topography, IOL tilt and decentration and refractive errors) were acquired from six patients implanted with monofocal IOLs and with ND complaints. A Harms tangent screen subjective method was used to localize in PFoV the perceived shadow (HvF). Following a previously presented methodology (M. State et al., IOVS, Vol.60, 3703, 2019), personalized Liou-Brennan (non)-sequential eye models were generated using the acquired biometrical data. Irradiance maps were computed using a polar coordinates detector and compared with the HvF data.
Results :
Mean axial length was 22.83 (21.05 – 24.80) mm, mean IOL power 24.4 (20.5 – 30.0) D, mean IOL tilt -1.86 (-6.21 – 2.96) degrees and mean decentration 0.16 (-0.27 – 0.44) mm. Average residual astigmatism difference between theoretical and measured data was 0.49 (0.02 – 0.97) D. Aligned with HvF data, the irradiance maps localized ND in the peripheral visual field up to 85 degrees.
Conclusions :
Previously presented theoretical results evidenced that in identical biometrical conditions, IOLs from different manufacturers with similar mechanical platforms but different optic edge designs are characterized by comparable ND profiles with the peripheral location of the shadows between 69 and 76 degrees. Further expanding the utilization of these eye models, the current results demonstrate their clinical relevance in terms of PFoV localization of ND.
This is a 2021 ARVO Annual Meeting abstract.