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The CRW1 Index: Identification of Eyes with Previous Myopic Laser Vision Correction Using Only a Swept-Source OCT
David L Cooke1, Kamran M Riaz2, David A Murphy2
1From the Great Lakes Eye Care, Saint Joseph, Michigan, USA; Department of Neurology and Ophthalmology, College of Osteopathic Medicine, Michigan State University, East Lansing, Michigan, USA.
A new Cooke-Riaz-Wendelstein (CRW1) index accurately detects previous myopic laser vision correction (M-LVC) using swept-source optical coherence tomography (SS-OCT) biometry. This tool aids surgeons in identifying eyes with prior M-LVC for improved surgical planning.
Area of Science:
- Ophthalmology
- Biomedical Engineering
- Medical Diagnostics
Background:
- Accurate identification of previous myopic laser vision correction (M-LVC) is crucial for safe and effective intraocular lens calculations.
- Traditional methods for detecting M-LVC can be time-consuming and may not always be reliable.
- Swept-source optical coherence tomography (SS-OCT) biometry offers advanced measurement capabilities.
Purpose of the Study:
- To develop and validate the Cooke-Riaz-Wendelstein (CRW1) index.
- To utilize SS-OCT biometry measurements, including total keratometry, for M-LVC detection.
- To provide a novel tool for alerting clinicians to prior M-LVC in measured eyes.
Main Methods:
- Retrospective, multicenter analysis of 49,199 SS-OCT biometry datasets.
- Segregation of eyes into laser vision correction (LVC) and non-LVC groups.
- Comparison of the CRW1 index accuracy against other diagnostic methods like keratometry ratios, topography, and tomography.
Main Results:
- The CRW1 index demonstrated a high positive predictive value (PPV) of 93%, outperforming the posterior/anterior corneal curvature ratio (65% PPV).
- CRW1 showed fewer false-positive results compared to the keratometry ratio.
- The CRW1 index performed comparably to topography software and surpassed other corneal imaging devices.
Conclusions:
- The CRW1 index, derived solely from SS-OCT biometry, offers a reliable method for detecting eyes with a high probability of prior M-LVC.
- An adjustable cutoff (CRW1-IS) enhances sensitivity for detecting more M-LVC eyes.
- These indices provide surgeons and researchers with an accessible tool for identifying eyes with previous M-LVC.
