IOLMaster — Axial Length Measurement
Pseudophakic Eyes.

Pseudophakic Eyes and False Images

Measuring Errors with Pseudophakic Eyes

Two peaks may appear when measuring pseudophakic eyes and with certain intraocular lenses (e.g. Acysof). The first peak (false) is from the IOL, while the second peak is produced by the retina. In this case, manual correction of the axis length is necessary. It is expedient to measure at a number of different points.

Because the IOL Master is an optical device, reflections off the surface of PMMA, acrylic intraocular, and occasionally silicone lenses, can sometimes produce false images. To avoid this, sample several areas around the reticule using the correct Measurement Technique.

If there is a visible reflection off the surface of an intraocular lens implant, excluding the responsible area will usually give correct results. When the axial length is much shorter than expected, a false image is probably in play. Then, a comparison with the fellow eye typically renders a significant difference, usually greater than 3.00 mm.