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Issue: Vol. 562 No. 2 (2026)
Section: Các bài báo
DOI: 10.51298/vmj.v562i2.18699
Date Published: 06/09/2026
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Downloads 36
How to Cite
Bùi , T. T. H., Huỳnh , T. K., Nguyễn , S. S., & Huỳnh , T. C. (2026). COMPARISON OF VAULT PREDICTION RELIABILITY IN IMPLANTABLE COLLAMER LENS SURGERY. Vietnam Medical Journal, 562(2). https://doi.org/10.51298/vmj.v562i2.18699

COMPARISON OF VAULT PREDICTION RELIABILITY IN IMPLANTABLE COLLAMER LENS SURGERY

Thị Thu Hương Bùi 1, , Tuấn Kiệt Huỳnh 1, Sỹ Sang Nguyễn 2, Tuấn Cường Huỳnh 3
1 Vietnam - Russian International Eye Hospital, Ho Chi Minh City
2 Eye Hospital of Ho Chi Minh City
3 Nguyen Tat Thanh University

Main Article Content

Abstract

Background: The vault (distance between the ICL and the crystalline lens) is a critical parameter determining the safety and efficacy of Implantable Collamer Lens (ICL) surgery. Accurate preoperative vault prediction is essential for selecting the appropriate lens size to prevent complications such as cataract formation (low vault) or angle-closure glaucoma (high vault).


Objectives: To compare the reliability of the Nakamura-Kunimoto (NK) and Kojima-Sasaki (KS) formulas in predicting postoperative vault in patients undergoing EVO-ICL V5 surgery at Vietnam-Russia International Eye Hospital.


Methods: A retrospective case series study was conducted on 52 eyes of 26 patients who underwent EVO-ICL V5 implantation from July to September 2025. Predicted vaults calculated by the NK and KS formulas using CASIA2 were compared with actual achieved vaults measured at 1 month postoperatively. Accuracy was evaluated using Mean Absolute Error (MAE), Mean Prediction Error (Bias), and paired t-test.


Results: The mean achieved vault was 646.6 ± 176.9 μm. The NK formula showed statistically significant underestimation (Bias -131.3 μm; p=0.004). The KS formula showed no significant difference from actual vault (Bias -62.7 μm; p=0.070). The MAE for KS (144.3 μm) was lower than NK (204.4 μm), representing a 29.4% improvement. Proportion achieving ideal vault (250-750 μm): KS 87.5%, NK 81.2%.


Conclusions: The KS formula demonstrated higher accuracy than the NK formula for predicting postoperative vault in ICL V5 surgery, particularly for the 12.6 mm lens size. The KS formula combined with CASIA2 AS-OCT is recommended for preoperative surgical planning.

Keywords

ICL, vault, Nakamura-Kunimoto, Kojima-Sasaki, AS-OCT, CASIA2.

Article Details

References

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