Used A-Scan Biometry Instruments

A-scan biometry is an invaluable tool used by ophthalmologists to measure the anatomical characteristics of the eye when planning cataract surgery. In order to achieve an optimal refractive outcome, accurate measurements of the axial length (AL), keratometry and anterior chamber depth (ACD) are essential to determine the correct power of an intraocular lens (IOL) before the lens is surgically implanted.

Biometry in ophthalmology continues to evolve, and while A-scan biometry is a widely accepted and used methodology for the measurement of axial length, it does have some limitations with regard to resolution and the ability to consistently direct the sound beam to a known location. Enter the ZEISS IOLMaster® A-Scan Biometer from Carl Zeiss Meditec.

The Gold Standard for IOL Power Calculations

In clinical practice, the ZEISS IOLMaster is the gold standard for IOL power calculations. A combined A-scan biometry instrument, the ZEISS IOLMaster facilitates fast and accurate measurements of eye length and surface curvature. Unlike ultrasound biometry – an invasive procedure that requires the use of anesthetics and direct contact with the cornea – the ZEISS IOLMaster is a non-contact device that incorporates extensive features to ensure patient safety and comfort. Only the manual alignment of the device to the patient’s eye is required; the rest of the process is fully automated.

The technique underlying ZEISS IOLMaster biometry is partial coherence interferometry. A signal is produced as a result of the interference between the light reflected by the tear film and the light reflected by the retinal pigmentary epithelium. Several studies of the ZEISS IOLMaster have demonstrated the accuracy and repeatability of its measurements.