Comparative Study Of Early Clinical Outcomes Between Newly Developed Acrylic Pc Phakic Iol(Kpl) And Collamer Pc Phakic Iol(Icl)

To compare early clinical, anterior-segment, and objective optical quality outcomes between a newly developed hydrophilic acrylic posterior-chamber phakic IOL (KPL, Koryo Eyetech Co., Seoul, Korea) and a collamer posterior-chamber phakic IOL (EVO ICL, STAAR Surgical, Monrovia, CA, USA).
KPL incorporates an enlarged 6.2-mm optic zone, a thinner profile than existing phakic IOLs, a 360-µm central hole for physiologic aqueous flow, and an expanded overall diameter range (11.75–13.75 mm) to enhance sizing flexibility and potentially improve visual quality.
We aimed to assess whether early visual and refractive outcomes with KPL were comparable to those with ICL, along with vaulting and anterior chamber angle safety.

Retrospective single-center chart review comparing KPL and ICL implantation, with preoperative demographic assessment, refraction, and anterior segment parameters, and standardized 1-month postoperative evaluation including refraction, visual acuity, AS-OCT–derived vault/angle metrics, and OQAS objective optical quality.

This retrospective comparative study included 30 eyes implanted with KPL and 60 eyes implanted with ICL (single surgeon, Jun-Oct 2025). At 1 month, refraction (sphere/cylinder/SE), visual acuity, and OQAS metrics (MTF cutoff, OSI, Strehl ratio) were evaluated. Vault and angle metrics (AOD500, ACA500; temporal/nasal) were measured by AS-OCT preoperatively and at 1 month. Between-group comparisons used Mann–Whitney U tests, and vault-angle changes association (ΔAOD500 and ΔACA500) used Spearman correlation. Angle metrics were compared at similar vault levels using vault strata (low <400, mid 400–700, high >700 µm) and in 1:1 vault-matched pairs (nearest-neighbor, no replacement; caliper 75 µm) with paired Wilcoxon signed-rank tests.

Preoperative demographics, anterior-segment biometry, and manifest refraction were comparable between KPL and ICL. At 1 month, refraction and visual acuity did not differ (all p>0.05). Vault was similar (p=0.338), and optical quality (OSI, MTF cutoff, Strehl) was comparable (all p>0.05). Vault–angle change analysis showed vault-related temporal angle narrowing in ICL but not KPL (ΔAOD500: ICL r=−0.247, p=0.048; KPL r=0.040, p=0.841; ΔACA500: ICL r=−0.262, p=0.043; KPL r=−0.017, p=0.931). In the high-vault stratum (>700 µm), KPL maintained larger AOD500/ACA500 (p=0.003/0.005). In 28 vault-matched pairs (caliper 75 µm; vault diff ~1 µm), AOD500 was higher with KPL (Wilcoxon p=0.016) and ACA500 showed a favorable trend (p=0.071).

In this early comparative study, KPL achieved refractive/visual outcomes comparable to ICL, with similar vaulting and optical quality at 1 month. Vault–angle change, stratified, and vault-matched analyses suggested less vault-associated temporal angle narrowing with KPL and better preservation of AOD/ACA at higher vault levels. Taken together, these results indicate overall postoperative performance and anatomic stability comparable to ICL. In addition, KPL demonstrated a more favorable anterior chamber angle-safety profile across analyses. KPL may be considered a clinically viable alternative to the widely used ICL; larger, longer-term prospective studies are needed to confirm safety and performance.