Dynamic assessment of variations in pupil diameter using swept-source anterior segment optical coherence tomography after phakic collamer lens implantation

Abstract

Purpose To dynamically assess variations in pupil diameter induced by changes in brightness in myopic eyes implanted with an implantable collamer lens (ICL, STAAR Surgical) with a central port. Methods This prospective, observational single-center case series study comprised 65 eyes from 65 consecutive patients undergoing ICL implant. A modified commercially available swept-source Fourier-domain anterior segment optical coherence tomography (AS-OCT) device was used for imaging and performing dynamic pupillometry under changing light conditions before and after a mean follow-up interval of four months after surgery. Results Preoperative mean pupil size under photopic conditions was 3.38 ± 0.64 mm; after surgery, this increased to 3.48 ± 0.61 mm. Mean pupil size under scotopic light conditions was 5.72 ± 0.79 mm before surgery and 5.84 ± 0.77 mm postoperatively. The differences between preoperative and postoperative pupil diameter in miosis and mydriasis were 0.10 ± 0.44 mm (P = 0.078) and 0.12 ± 0.58 mm (P = 0.098), respectively. The scotopic pupil exceeded the optic zone of the implanted lens in 39 eyes (60%). The mean central vault value was 412 ± 177 μm under maximum miosis and 506 ± 190 μm under maximum mydriasis. We found a positive correlation between vault and differences in pupil diameter under all light conditions (P < 0.05). Conclusion Dynamic AS-OCT enables a very precise determination of the pupillary diameter in the iris plane. The changes in the pupil diameter under different light conditions after the implantation of an ICL are related to the postoperative vault.

Prediction of excessively low vault after implantable collamer lens implantation using iris morphology

“…In addition, our study also showed that the PD was a relevant parameter related to the postoperative vault. Consistently, Gonzalez-Lopez et al ( 18 ) observed that the changes in the pupil size under different light conditions were associated with the vault after ICL implantation based on dynamic AS-OCT. Myopic eyes with larger pupil size were often predisposed to higher postoperative vault ( 19 ). These findings indicated that the causative factor for the change in pupil size might be considered preoperatively.…”

Intraocular Implantable Collamer Lens with a Central Hole Implantation: Safety, Efficacy, and Patient Outcomes

“… 57 Recently, a study investigating ICL vaults in different light conditions found that these values were dynamic and positively correlated with pupil diameter. 62 Finally, crystalline lens rise was found to be another independent factor contributing to differences in postoperative vaulting and could possibly be used preoperatively for ICL size calculation. 63 These parameters may be helpful in ICL vault prediction and improving its sizing formula.…”

“…63 These parameters may be helpful in ICL vault prediction and improving its sizing formula. 62,63 Intraocular Pressure…”

Implantable collamer lens sizing based on measurement of the sulcus-to-sulcus distance in ultrasound biomicroscopy video clips and ZZ ICL formula

“…Sixth, instantaneous vault height was obtained, and this may have introduced information bias. Indeed, vault dynamism is an important component of ICL formulas [ 28 ]. Finally, the study follow-up was limited to 3 months, so longer-term outcomes could not be evaluated.…”