Taking presbyLASIK to the max

January 1, 2007

Although presbyLASIK is still, by no means, perfect, it seems to present a good solution for certain cases, particularly in myopes and hyperopes.

Using excimer laser surgery to correct presbyopia is not a new concept. In fact, the technique was first presented in May 1991 by German refractive surgeon Till Anschutz, MD. More than 15 years on and the procedure is beginning to become accepted by some refractive surgeons as a viable treatment option for presbyopia.

This increasing acknowledgement was accompanied by the birth of the word presbyLASIK.

Until now, presbyLASIK as a solution for presbyopia has been slow on the uptake, with the first generation of procedures being associated with certain complications, such as increased risk of developing visual complications and a need for further correction with age if treated early. Although it does offer a solution that is less invasive than intraocular surgery - it preserves the clear lens, can be fully customized for the patient and is easy and cost-effective - it does involve a permanent change to the cornea and may result in contrast sensitivity loss.

Jorge L. Alió, MD of the VISSUM, Instituto Oftalmologico de Alicante in Alicante, Spain is an advocate of the presbyLASIK technique and has been actively involved in seeking the ultimate ablation method that, not only accurately provides his patients with near vision, but does so safely and effectively.

Stepladder approach to identifying a solution

In his quest for a precise excimer laser solution for presbyopia, Dr Alió teamed up with fellow refractive surgeons Roberto Pinelli, MD of the Istituto Laser Microchirurgia Oculare (ILMO) in Brescia, Italy and Sudhir Patel, MD of the VISSUM, Instituto Oftalmologico de Alicante, Spain. Together, the team developed PresbyMax; a stepladder approach to the correction of early and intermediate presbyopia based on multifocal ablation patterns (central and peripheral techniques), using Schwind's ESIRIS excimer laser with ORK-CAM software. This system couples diagnostic, custom ablation manager software with the laser to deliver aspherical aberration-free profiles.

The team conducted a study, using central hyperopic PresbyMax to treat hyperopic patients who fell into the following criteria: sphere ±4.0 D, astigmatism ≤1.50 D, near visual acuity (VA) of J2 to J3 with a near add of +1.50 D, normal corneal topography, no dry eye and pachymetry ≥500 μm.

Let the results speak

At six-months postoperatively, although there was an increase in route mean squared (RMS) coma-like aberrations (0.35 μm preop to 0.51 μm postop), there was a marked decrease in RMS sphere (0.32 μm to 0.15 μm). Furthermore, 80% of patients had distance uncorrected vision of 0.8, whilst 92% could read J3 or more. These results remained stable over time.

The team used their clinical experience to develop a model that predicted visual outcomes of a central presbyMax procedure. Having compared actual clinical performance versus the theoretical model, they were able to confirm that they had developed a good treatment predictor.