Phacoemulsification with IOL implantation shows higher IOL prediction error in Chinese PACG patients

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medRxiv Published April 16, 2026 Medically reviewed April 25, 2026 Study authors: Wang, L.; Yang, Y.; Ng, T. K.; Chen, J.; Sun, X. DOI ↗ By Dr. Lars van Dijk, PhD · Surgical, Procedural & Diagnostic

Key Takeaway

Consider higher IOL prediction error in PACG patients, especially acute cases with axial length ≥22 mm.

This observational study included 165 Chinese patients with primary angle closure glaucoma (PACG) and 53 cataract patients. All participants underwent phacoemulsification and intraocular lens (IOL) implantation (PEI) surgery, with PACG patients also receiving goniosynechialysis (GSL), while cataract patients received only PEI surgery as a comparator. The primary outcome was prediction error (PE) of IOL power calculation, with secondary outcomes including mean absolute error (MAE), median absolute error (MedAE), and proportions of eyes within specific PE ranges.

Main results showed that PACG patients had significantly higher absolute PE compared to control subjects, with this effect especially pronounced in acute PACG patients. Axial length (AL), changes in aqueous depth pre- and post-surgery (ΔAD), and the ratio of ΔAD/AL were significantly associated with the PE. Specifically, the association of ΔAD with PE was found in PACG patients with AL ≥ 22 mm. Exact numerical data for these outcomes were not reported in the input.

Safety and tolerability data were not reported. Key limitations were not specified in the input, but as an observational study, it cannot establish causality. Practice relevance suggests that precisely predicting ΔAD is necessary for acute PACG patients, especially those with AL ≥ 22 mm, to improve refractive outcomes, but this should be applied with restraint given the evidence limitations.

Study Details

EvidenceLevel 5

PublishedApr 2026

View Original Abstract ↓

Purpose: To identify the ocular biometric parameters associated with refractive outcomes in Chinese Primary angle closure glaucoma (PACG) patients receiving phacoemulsification and intraocular lens (IOL) implantation (PEI) surgery. Methods: 165 Chinese PACG patients receiving PEI and goniosynechialysis (GSL) and 53 cataract patients as controls only receiving PEI surgery were recruited. The prediction accuracy of IOL power calculation was assessed by the prediction error (PE), mean absolute error (MAE), median absolute error (MedAE), and proportions of eyes with a PE within {+/-} 0.25 diopters (D), {+/-} 0.50 D, {+/-} 0.75 D, and {+/-} 1.00 D. The association of different ocular biometric parameters with the PE of IOL calculation were evaluated. Results: The PACG patients had significantly higher absolute of PE as compared to the control subjects, especially the acute PACG patients. The axial length (AL), changes in aqueous depth pre- and post-surgery ({bigtriangleup}AD), and the ratio of {bigtriangleup}AD/AL were significantly associated with the PE in acute PACG patients. The association of {bigtriangleup}AD with the PE of IOL power calculation was found in PACG patients with AL [≥] 22 mm. Conclusions: This study revealed the association of AL and {bigtriangleup}AD with the PE of IOL calculation in Chinese PACG patients. Precisely predict the {bigtriangleup}AD is necessary for acute PACG patients, especially for those with AL [≥] 22 mm, to improve the refractive outcomes.