Correlation between different measurements within the eye relative to phakic intraocular lens implantation.

Purpose: To obtain measurements of the white-to-white distance and the anterior chamber and ciliary sulcus diameters in phakic human eyes obtained post-mortem to find a correlation between these measurements.

Setting: David J. Apple, MD Laboratories for Ophthalmic Devices Research, John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, USA.

Methods: Twenty-two phakic human eyes obtained from eye banks within 24 hours of death were evaluated. The following measurements were performed: white-to-white distance, anterior chamber diameter with a plastic sizer after a small limbal incision, and anterior chamber and ciliary sulcus diameters after fixation and sagittal section of the eyes. The first 10 eyes were studied at the 6 o'clock to 12 o'clock meridian and the last 12 eyes, at the 3 o'clock to 9 o'clock meridian.

Results: A positive correlation was found between the white-to-white measurements and the anterior chamber diameter in the 10 eyes studied at the 6 o'clock to 12 o'clock meridian but not in the 12 eyes studied at the 3 o'clock to 9 o'clock meridian. The latter is the meridian frequently used by surgeons to perform white-to-white measurements and thus choose the overall size of the phakic intraocular lens to be implanted. No correlation was found between the white-to-white measurements and the ciliary sulcus diameter in the 2 meridians.

Conclusion: Experimental studies using cadaver eyes are helpful in evaluating sizing techniques for phakic IOL implantation as well as in better understanding the anatomical relationships between ocular structures.