In November 1997, I began implanting the Array multifocal lens (Advanced Medical Optics, Inc., Santa Ana, CA) in cataractous eyes. During the year 2000, I started performing PRELEX in presbyopic eyes, and I personally underwent the procedure in 2002 (Figure 1). My candidates are aged 45 years or older, have significant presbyopia, and wish to decrease their dependence on glasses through refractive surgery—a goal they could not achieve without problems using monovision LASIK. Risk is inherent to any form of intraocular surgery, and this article describes why it is worth taking with PRELEX.
THE RISKS OF THE PROCEDURE The risks of PRELEX are the same as for cataract surgery. Potential vision-threatening complications include: endophthalmitis, possibly resulting in the loss of the eye; CME; choroidal hemorrhage; PCO; the loss of vitreous, BCVA, or UCVA; glaucoma; uveitis; and corneal decompensation. Nonvision-threatening complications include increased ocular dryness, foreign-body sensation, unwanted visual phenomena, changes in the axis or power of astigmatism, and an increase in the number of or alteration in the size or shape of floaters.
BENEFITS For the emmetrope and hyperope, presbyopia is truly a curse. Unlike the myopic presbyope, who can simply remove his glasses to read, these individuals lack functional near vision. Prior to undergoing PRELEX, I was emmetropic with 20/15 UCVA at distance. My level of presbyopia was significantly greater than that of an average person my age, however. Uncorrected, my right eye saw J16, and my left eye was 20/400 distance equivalent on the Rosenbaum Pocket Vision Screener (McCoy Health Science Supply, Maryland Heights, MO).
I totally depended on my glasses to see at near. In the examination lanes, I was unable without spectacle correction to read my watch, patients' charts, the phoropter, or the tonometer. When wearing my glasses, however, I could not complete half my tasks, such as using the slit lamp or indirect ophthalmoscope. I constantly removed and replaced my spectacles every day when performing ophthalmologic exams. In the OR, I needed my glasses in order to incise the drape prior to performing intraocular surgery. I desired the same quality of vision attained by my cataract and PRELEX patients who had received the Array.
My estimation of the risks associated with PRELEX is influenced by my personal experience implanting the Array lens in approximately 2,000 cataractous and 200 PRELEX eyes. A retrospective chart review of my first 62 PRELEX procedures revealed a mean postoperative monocular UCVA of 20/24 and J2, as well as a mean postoperative binocular UCVA of 20/20 and J1. Surgeons should always evaluate the potential pros and cons of a procedure, and I believe that the benefits of PRELEX far outweigh its risks.
Because I believe that most serious, vision-threatening complications of PRELEX relate to the surgical experience, I sought a seasoned cataract surgeon who operated in his own ASC and could, therefore, more completely control the perisurgical environment. I also wanted my surgeon to have extensive experience implanting the Array. In May 2002, R. Bruce Wallace III, MD, performed PRELEX on me at his ASC in Alexandria, Louisiana. I credit him with my excellent surgical outcome. My UCVA is 20/15 monocularly in both eyes and 20/10 binocularly. My near vision is J1 monocularly and J1+ binocularly. As an ophthalmologist, the procedure has not compromised my vision in any way at the slit lamp, indirect ophthalmoscope, or operating microscope (Figure 2). I can now incise the drape prior to performing cataract surgery.
CONCLUSION PRELEX addresses the total visual needs of the presbyope: distance, near, and intermediate vision. This procedure is our only current means for providing patients with simultaneous vision at near in both eyes. Simultaneously correcting eyes for distance and near provides individuals with the depth perception they would lack after undergoing LASIK monovision.
PRELEX is not appropriate for all patients, however. Candidates should receive appropriate preoperative education about the procedure and its risks. Additionally, excellent biometry is crucial to accurate IOL power calculations and successful outcomes.
L. Andrew Watkins, MD, is in private practice in Houston. He serves as a consultant for Advanced Medical Optics, Inc., but holds no direct financial interest in the products mentioned herein. Dr. Watkins may be reached at (713) 862-6631; watkins@fc.net.
