In the age of presbyopia-correcting IOLs, a surgeon now has the additional armor to offer patients the greatest care and visual outcomes. I currently use multifocal as well as accommodating IOLs in the treatment of presbyopia. I opt to use an accommodating IOL in patients who require prelex (ie, refractive lens exchange), and I often use it as a routine in cataract patients. I prefer the Tetraflex Presbyopic IOL (Lenstec, St. Petersburg, Florida) to other accommodating lenses. This IOLs provides patients with excellent distance and intermediate vision as well as useful near vision.

The Tetraflex has a patented 5º-contoured haptic design, and it is activated during the eye's natural accommodation process. It appears that the IOL does not have to move as much as you would predict to get the increased power. So, some pseudoaccommodation probably occurrs. This haptic design works with vitreous movement and ciliary swelling in the eye to create clear near vision through maximum forward movement and a swift return to the flat position for clear intermediate and distance vision. Its square edge optic helps reduce posterior capsule opacification as well as other common cataract complications.

One advantage of the Tetraflex is that the learning curve is practically nonexistent, and I have had good results thus far. This microincisional lens has a 5.75-mm optic to prevent the risk of halos or glare. In the 147 patients I have implanted with the Tetraflex, only one patient complained of halos. This is much less than you find with multifocal IOLs.

PATIENTS WITH REALISTIC EXPECTATIONS
I use the Tetraflex in place of a multifocal IOL in patients whom I feel are not suited for a multifocal implant. It is best used in emmetropic and hyperopic patients who have realistic expectations. Patients who are more interested in having better distance and intermediate vision, and who are not too concerned about being able to read the tiniest print, are the likely candidate for an accommodating lens. Patients with severe dry eye; ocular infection; severe ophthalmic diseases (ie, macular disease, uveitis, glaucoma, or retinal disease); uncontrolled systemic diseases (eg, diabetes, hypertension, or cardiovascular disease); or those with 1.00 D or greater of preoperative corneal astigmatism should not receive the Tetraflex IOL.

If a patient is concerned with reading tiny print, or if they need good near vision as a requirement for their job, I will alternatively implant a multifocal IOL. These lenses offer the best near vision, at the sacrifice of intermediate vision. Therefore, in general, I use the Tetraflex Presbyopic IOL, when appropriate, in patients who either have routine cataract surgery, or are having refractive lens exchange. Approximately 30% of my patients over the past 18 months have received accommodating IOLs.

I have a good amount of experience with all types of IOLs. I use the Tecnis Multifocal (Advanced Medical Optics Inc., Santa Ana, California), and I am also currently involved in a trial of the Tecnis Multifocal versus ReStor (Alcon Laboratories, Inc., Fort Worth, Texas). I am finding that I treat the same approximate number of patients with the Tetraflex as I would with a regular multifocal.

CENTERS WELL
I have chosen the Tetraflex over other accommodating lenses because it centers very well. There is not much difficulty in the surgical technique, and it is also a very easy lens to load in the injector system. (See Lenstec Recommendations for the recommended surgical procedure for the Tetraflex IOL.) A lot of lenses are not as easily loaded—they are a bit figidity—but the Tetraflex is very simple, very easy, and it works really well.

With a multifocal IOL, if the refractive target is right, patients may often read at about J1 or J2. This is not the case with accommodating IOLs, however, I have noticed additional success in patients who complete accommodating exercises. These patients may accomplish J4. During these exercises, the patient covers their nonoperated eye, or if they have both eyes done, they use both eyes. First, the patient finds the ideal space for a test type that is easy to see (ie, approximately J12). Having found the ideal space in which to read the J12 type, they then bring the print slowly toward them, until their near vision starts to blur. The patient then brings it out again. With this exercise, they relearn how to use their accommodative reflex. That definitely improves their reading ability, so much so that they may go from J10 to about J4 once they do the exercises.

PAYMENT PREMIUM
One drawback associated with accommodating lenses is the premium patients are forced to pay. Because health insurers are currently not reimbursing for these lenses, some patients decide not pay the extra cost for an accommodating lens. In those patients, I would use a high-quality aspheric monofocal IOL (eg, Tecnis Monofocal; Advanced Medical Optics, Inc.). I am finding that it is a bit more commonplace for patients to pay extra for that accommodating IOL, however, we are fighting to get health insurers to step up and actually pay for them. Patients are paying for 21st-century subscriptions and only receiving 20th- century medicine. I think we have to address that situation and get the health insurers to pay for it, just as they did with better hip prostheses, for example. If it does go through, and the health insurers will pay for the accommodating IOLs, I perceivably would use an accommodating or multifocal lens almost universally, as opposed to a high-quality monofocal IOL. I would reserve monofocal IOLs for diabetic patients and others with retinal problems.

The use of accommodating IOLs, including the Tetraflex Presbyopic IOL, is rising, particularly in the United Kingdom, but also throughout Europe. The Tetraflex is a great lens for the treatment of presbyopia; I find that the lens centers very well. Additionally, the lens' refractive range is very good (ie, whole increments from 5.00 D to 18.00 D and 25.00 D to 30.00 D, and half increments from 18.00 D to 25.00 D). Recently, the company has made available 0.20 D steps, so that you can really get a fine tune of your refractive outcome if you have good biometry.

Mr. Conall Hurley is Medical Director of the Ardfallen Eye Clinic, in Cork, Ireland. He states that he has no financial interest in the products or companies mentioned. Mr. Hurley may be reached at +00 353 21 4291705; cfhurley@eircom.net; or ardfalleneyeclinic@eircom.net.