Pupil Diameter Changes in High Myopes after Collamer Lens Implantation

Abstract

PurposeTo observe the changes in pupil size under photopic and scotopic conditions after Implantable Collamer Lens (ICL) implantations in eyes with high myopia.MethodsThe ICL was implanted in 90 eyes belonging to 45 patients with high myopia. Photopic pupil diameters, scotopic pupil diameters, anterior chamber depths, and ICL vaults were examined at the preoperative, postoperative 1-month, and postoperative 3-month stages. The preoperative and postoperative photopic pupil diameters and scotopic pupil diameters were also compared with each other to note the differences between them. The correlations between preoperative and postoperative pupil diameter changes under different light conditions and presurgical refractive error were analyzed alongside patient’s age and ICL vault.ResultsPupil diameters at both postoperative 1-month and postoperative 3-month stages were smaller than those before operation in distinct light environments, as well as pupil constriction amplitude. Correlation analysis showed that there was a statistically significant correlation between pupil diameter changes under different light conditions and presurgical refractive error at 1 month and 3 months after ICL implantation; pupil diameter decreased more when presurgical refractive error powers were less myopic. Statistically significant correlations were not found, however, with patient’s age and ICL vault. Postoperative 1-month and mean postoperative 3-month anterior chamber depths were decreased when compared with preoperative anterior chamber depths. Statistically significant correlations were found in change in preoperative and postoperative anterior chamber depth and ICL vault. No statistically significant difference was found between ICL vault at the postoperative 1-month and postoperative 3-month stages.ConclusionsPupil diameter may decrease at the 1- and 3-month stages after ICL implantation under both photopic and scotopic conditions. This indicates that reduction of pupil diameter may be caused by mechanical contact between the ICL and the posterior iris surface.

Anterior Chamber Changes After Implantable Collamer Lens Implantation in High Myopia Using Pentacam: A Prospective Study

“…Although the change was statistically insignificant, it is worth mentioning that the p value was 0.062, which means it was close to the significance. This was different from results of previous studies [ 13 , 14 ], where a significant reduction in PD was observed both 1 and 3 months after ICL implantation. Li and associates [ 13 ] attributed this reduction to the contact between the iris and ICL, which limits postoperative pupil movements, as they found a significant correlation between lower degrees of myopia and decreased size of the pupil.…”

“…This was different from results of previous studies [ 13 , 14 ], where a significant reduction in PD was observed both 1 and 3 months after ICL implantation. Li and associates [ 13 ] attributed this reduction to the contact between the iris and ICL, which limits postoperative pupil movements, as they found a significant correlation between lower degrees of myopia and decreased size of the pupil. Our results were different perhaps because our patients had higher degrees of myopia as mean SE was −16.91 ± 2.37 D in our study, while it was −12.50 ± 4.28 in their study.…”

“…The implantation of ICL has been shown to be an effective surgical treatment for the correction of refractive errors, offering good optical quality. With expanding use of ICLs worldwide, several studies addressing their efficacy and safety have been done and are still of current interest [ 1 , 2 , 6 , 10 – 13 ]. Our study aimed to evaluate AC changes after ICL implantation using the Pentacam.…”

Evaluation of Disk Halo Size after Implantation of a Collamer Lens with a Central Hole (ICL V4c)

“…Reductions in postoperative contraction amplitude, contraction velocity, and dilation velocity were observed in this study. The changes in contraction amplitude were consistent with previous studies [8, 9]. In terms of velocity, Totsuka et al found no significant changes in maximum constriction velocity or maximum dilation velocity, between preoperative measurements and measurements at 1, 3, and 6 months after ICL V4c implantation [21].…”

“…Kamiya et al [23] found that pupil diameters of patients aged 35.7 ± 12.0 years were transiently reduced at 1 day after ICL implantation, then returned to preoperative levels at 1 week after implantation and subsequently remained stable. Two studies in patients who were less than 30 years of age found that the recovery time was more than 3 months [7, 8]. Thus, the occurrence of a reduced pupillary light response might be a short-term change.…”