Predictive Value of Preoperative Simulated Night Vision Disturbance Psychological Testing and the Impact of Pupil...

To evaluate the predictive utility of preoperative simulated night vision disturbance (NVD) psychological testing for postoperative visual disturbances and investigate the influence of pupil size on visual quality following bilateral keratorefractive lenticule extraction (KLEx). A prospective case-control study design was used.

A total of 121 eyes (121 patients) that underwent KLEx for myopia and myopic astigmatism at the Zhongshan Ophthalmic Center from May 2024 to July 2024 were analyzed. These patients were stratified into large and small pupil groups based on preoperative pupil diameters measured with Sirius (CSO). Participants completed a simulated NVD psychological test, preoperative questionnaire, and objective and subjective visual quality measurement. Visual quality was assessed using the Objective Scattering Index (OSI), modulation transfer function (MTF) cut-off, Strehl ratio (SR), wavefront aberrations, contrast sensitivity under four lighting conditions, and NVD survey. Follow-up visits occurred at 1 week and 1, 3, and 6 months postoperatively. Generalized estimating equations were employed to analyze changes in visual quality over time within groups and differences between groups at various time points.

Simulated NVD test outcomes were predictive of postoperative NVDs in 85% of the large pupil group and 74% of the small pupil group. The large pupil group exhibited more severe NVDs at 1 and 3 months postoperatively (P = .015 and .001, respectively). Preoperative NVD severity scores were significantly higher than at any postoperative time point (P < .05), and 92% of participants deemed the preoperative test necessary. OSI, MTF cut-off, SR, and contrast sensitivity did not significantly differ between groups at any time point. MTF cut-off values returned to baseline at 1 month in the small pupil group (P = .214) and at 3 months in the large pupil group (P = .761). By 6 months, spherical aberrations increased significantly in the large pupil group (P < .01) but remained stable in the small pupil group (P = .342). At 6 months postoperatively, the small pupil group showed significant improvements in contrast sensitivity under all lighting conditions, whereas the large pupil group improved only under photopic conditions.

Visual quality temporarily declines after KLEx but progressively recovers, with faster recovery in patients with smaller pupils. Adaptation to NVDs is also faster in this group. Preoperative simulated NVD psychological testing is a valuable predictive tool for postoperative NVDs, although it tends to overestimate symptom severity compared to actual postoperative outcomes.