Correction Of Astigmatism With Toric Implantable Posterior Chamber Collamer Phakic Lens: Comparison Between Low And High Astigmatism Groups

Published 2022 - 40th Congress of the ESCRS

Reference: FPT07.04 | Type: Free paper | DOI: 10.82333/sdnw-km63

Authors: Álvaro Silva* ¹ , Tiago Monteiro ¹ , Fernando Faria Correia ¹ , Nuno Franqueira ¹ , José Mendes ¹ , Christophe Pinto ¹ , Carlos Cruz ¹ , Rui Silva ¹ , Fernando Vaz ¹

¹Ophthalmology,Hospital de Braga,Braga,Portugal

Purpose

To compare the refractive results, safety and efficacy of toric posterior chamber phakic lens (ICL V4c and V5) for the correction of low and high astigmatism refractive errors.

Setting

Department of ophthalmology, Hospital de Braga, Braga, Portugal.

Methods

A retrospective, comparative, study was designed that included 205 eyes submitted to refractive surgery with implantation of posterior chamber collamer phakic intraocular lens (pIOL) in Hospital de Braga from 2014 to 2019. Two groups were created according to preoperative manifest cylinder: low astigmatism (group 1) if <2.5 diopters, which included 97 eyes, and high astigmatism (group 2) for ≥2.5 diopters, composed of 108 eyes. The two groups were compared regarding efficacy, safety and predictability Astigmatic refractive analysis was performed using Alpins method. The follow-up was 12 months

Results

Mean preoperative cylinder was -1.85 ±0.27 (group 1) and -3.52 ± 0.95 (group 2). Best corrected visual acuity was 0.10 ±0.10 and 0.13 ±0.11 logMAR (p=0.02), respectively.

Postoperatively, uncorrected visual acuity was 0.05 ±0.10 and 0.08 ±0.12 logMAR (p=0.15), respectively. The safety indexes were 1.25 ±0.30 and 1.30 ±0.29 (p=0.07). The efficacy indexes were 1.15 ±0.28 and 1.16 ±0.26 (p=0.58). In 71.1% of cases the manifest cylinder was within ±0.50D (group 1) and 57.5%, in group 2, were within ±0.50D (p=0.04).

The correction index was 0.91 ±0.46 (group 1) and 0.89 ±0.17 (group 2) (p=0.81). The index of success was 0.54 ±0.45 and 0.29 ±0.16, respectively (p<0.01). The surgical induced astigmatism was 1.37D ±0.66 and 2.69D ±1.00 (p<0.01).

Conclusions

Correction of astigmatic refractive error with toric posterior chamber collamer phakic lens implantation provides good refractive and visual results regardless of preoperative magnitude of astigmatism levels. Additionally, they have an excellent safety profile (no vision threatening conditions were reported in our study). Through vectorial analysis we ascertained the reduction in cylinder was more effective in group 2.