Optical biometry is a precise, non-contact measurement of the eye's dimensions, most commonly used to calculate the correct power of an intraocular lens (IOL) before cataract surgery. Using light rather than sound, this technology measures the eye with a high degree of accuracy, helping ensure the best possible visual outcome after surgery.
What Optical Biometry Measures
During an optical biometry scan, the device measures several key dimensions of the eye, including its axial length (the distance from front to back), the curvature of the cornea, and the depth of the anterior chamber. These measurements are combined using specialized formulas to calculate the ideal power for the artificial lens that will replace your natural lens during cataract surgery.
How the Scan Works
The test is quick, painless, and non-contact — you'll simply be asked to look at a fixation light while the device takes its measurements, typically completing the scan in well under a minute per eye. No numbing drops or contact with the eye are needed, and there's no downtime afterward.
Why Accuracy Matters
Because the lens power selected for cataract surgery is calculated based on these measurements, precision here has a direct impact on how well your vision is corrected after surgery. Modern optical biometry is generally more precise and more comfortable for patients than older ultrasound-based measurement methods, which is why it's the preferred approach for cataract surgery planning at our practice.