The Comparison of IOL Formulas in Eyes With PCE≥15um Undergoing Cataract Surgery
Conditions
Keywords
IOL formulas, posterior corneal elevation, refractive outcomes
Brief summary
The goal of this observational study is to evaluate the long-term refractive outcomes of advanced intraocular lens (IOL) power calculation formulas in cataract patients with posterior corneal elevation (PCE ≥ 15 μm). The main question it aims to answer is: Do PK-based formulas provide superior refractive accuracy compared with Without-PK-based formulas in patients with elevated posterior corneal surfaces? Participants undergoing routine cataract surgery will have their biometry measured by both Pentacam AXL and IOLMaster 700, and postoperative refraction will be collected at 1 month, 3 months, and 6 months postoperatively.
Interventions
OTHERIntraocular lens calculation formulas
The study evaluates four groups of intraocular lens (IOL) power calculation formulas, totaling 13 distinct formulas, to compare their accuracy in predicting postoperative refractive outcomes in cataract patients. Group 1 - Without PK: Barrett Universal II (BUⅡ), EVO 2.0, Kane, Hill-RBF 3.0, LADAS, Pearl-DGS, and K6, which do not incorporate PK. Group 2 - Measured PK-I: Barrett TK measured (I) and EVO Advanced (I), which use measured PK from IOLMaster 700. Group 3 - Measured PK-P: Barrett TK measured (P) and EVO Advanced (P), which use measured PK from Pentacam AXL. Group 4 - Predicted PK: Barrett TK predicted and Kane KC, which estimate PK through prediction algorithms rather than direct measurement. This observational study does not introduce experimental procedures; all data are collected during routine cataract surgery and postoperative follow-up to determine the comparative accuracy of these formulas
Sponsors
Second Affiliated Hospital of Xi'an Jiaotong University
Study design
Observational model
OTHER
Time perspective
RETROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
18 Years to 85 Years
Healthy volunteers
No
Inclusion criteria
* Meeting the indications for cataract surgery, and undergoing Phacoemulsification + IOL implantation performed by the same surgeon. * Preoperative biometry performed with IOLMaster 700 and Pentacam AXL, with a posterior corneal elevation greater than 15 μm within the central 5 mm zone on Scheimpflug imaging, and a central corneal thickness \> 500 μm. * Surgery completed successfully without any intraoperative or postoperative complications. * Postoperative subjective refraction performed at 1 month after surgery by the same experienced optometrist.
Exclusion criteria
* Patients with pterygium, corneal diseases, glaucoma, uveitis, or fundus diseases (such as macular edema, retinal detachment), excluding high myopia. * History of ocular trauma or previous intraocular surgery. * Occurrence of intraoperative or postoperative complications, such as iris injury, posterior capsule rupture, IOL dislocation, vitreous prolapse, or vitreous hemorrhage. * Postoperative best corrected visual acuity (BCVA) worse than 0.5. * Difference between postoperative subjective refraction and preoperative target refraction greater than 2.00 D. * Incomplete measurement data.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| absolute SEQ-PE(accuracy) | From enrollment to the end of treatment at 6 months | the absolute values of SEQ-PE |
| SEQ-PE(trueness) | From enrollment to the end of treatment at 6 months | Spherical Equivalent Prediction Error 1. SEQ=Sphere+2Cylinder 2. PE=Postoperative Manifest SEQ-Predicted SEQ |
| Precision | From enrollment to the end of treatment at 6 months | Precision refers to the consistency of the prediction errors (PE) of a formula across a study population, indicating how closely the individual prediction errors cluster around the central tendency (e.g., mean or median). A formula with higher precision shows smaller variability in its prediction errors. |
Countries
China
Outcome results
None listed