It's Time to Decide
Answers to your clinical and practice management questions about phakic IOLs
BY JOHN A. VUKICH, M.D.

By the end of this year, it's likely that U.S. ophthalmologists will be able to add phakic IOLs to their surgical armamentarium. Both the STAAR Visian Implantable Collamer Lens (ICL) and the Ophtec Artisan (which will be marketed in the United States by Advanced Medical Optics (AMO) as the Verisyse lens) have received approvable votes from the FDA's Ophthalmic Devices Advisory Panel and are awaiting final approval by the agency.

A major difference between the two lenses is their positioning within the eye. The Visian ICL is a foldable posterior chamber lens that rests behind the iris in the ciliary sulcus. The Verisyse lens is an anterior chamber, iris-clip lens. In this article, I'll discuss the capabilities of these two lenses and how you can best integrate phakic IOL procedures into your surgical practice.

Their Appeal Should Grow

The first approvals for these phakic IOLs will be for the correction of myopia only, although both lenses are in clinical trials for use in hyperopes. The Visian is likely to be initially approved to correct a much broader range of myopia (-3D to -20D) than the Verisyse (-9D to -20D).

Toric versions are under investigation as well, and will certainly broaden the appeal of the lenses, once approved. The phakic IOL is most likely to first find acceptance as a modality for correcting high myopes who are outside the range for LASIK and PRK. But over time, as surgeons become more comfortable with them, I think use of these lenses will expand.

Unlike LASIK, phakic IOLs aren't "dose-dependent." The operation is the same regardless of the amount of the correction. So there's good reason to anticipate that if a surgeon is comfortable with the safety and efficacy of a phakic IOL in a -10D myope, he or she will be just as comfortable using it for a more moderate myope.

ILLUSTRATION: JOEL AND SHARON HARRIS

After the initial phase of gearing up the practice to offer phakic IOLs and implanting them in high myopes, I think surgeons will begin considering them for lower myopic patients with marginal corneal thickness or abnormal features on topography. With the availability of phakic IOLs, there will be no reason to push the envelope to do LASIK on these patients.

Ultimately, each surgeon will have to find a personal cutoff below which he or she chooses laser and above which he or she chooses an intraocular procedure, all else being equal.

A quick word about the potential for phakic IOLs to treat hyperopia: While phakic IOLs appear to be efficacious in the correction of hyperopia, there are physical constraints to implanting them in hyperopic eyes with shallower anterior chambers. These constraints will likely limit the number of hyperopic patients who can benefit from a phakic IOL.

Future hyperopic approvals will be quite beneficial, however, for clinicians who want to use a phakic IOL off-label as a secondary procedure for a myopic patient who was overcorrected by a previous corneal refractive procedure. Particularly if the patient has a deep anterior chamber and additional corneal procedures are contraindicated.

Certainly, phakic IOLs will never replace LASIK, but I believe they are synergistic modalities.

Whose Ace is This?

Because phakic IOLs bridge the cataract-refractive divide, many people wonder just which anterior segment surgeons will be the first to play the phakic IOL card.

In my opinion, comprehensive surgeons who do both types of surgery will find it easiest to incorporate phakic IOLs into their armamentarium, while ophthalmologists who do only cataract surgery will find it most difficult.

Cataract surgeons certainly have the expertise to do this surgery, but they'll have a difficult time positioning it in their practice if they don't also offer laser procedures. Imagine trying to market to the refractive segment, but being forced to turn away everyone under -3D -- the lowest myope for which either lens will be approved. That represents a huge segment of the myopic population and presents a real challenge in terms of growing a practice.

On the other hand, having the ability to extend their current dioptric range well beyond the upper limits of LASIK will enhance the current refractive surgeon's practice.

Also, I think we have all come to accept that no single procedure will have perfect outcomes every time. A small percentage of phakic IOL patients could benefit from a laser "touchup" that only the comprehensive surgeon can provide.

This isn't to say that a refractive-only or cataract-only surgeon can't offer phakic IOLs, but it will require a lot more practice preparation to make it viable.

Gearing up Your Practice

Now is a good time for all anterior segment practices to begin thinking about how to successfully incorporate phakic IOL implantation into the practice's offerings. I can identify at least five areas that require some strategic thinking and/or preparation before "going phakic" can become a reality:

Surgical skills. As with any procedure, there's a learning curve for phakic IOLs, but it's likely to be a very short one for anyone with an active cataract practice, as the basic skills are the same. The Artisan lens probably has a little bit more of a learning curve because it requires a larger incision and a two-handed technique that might be unfamiliar to some surgeons. With the ICL, surgeons will have to take care in loading it into the injector mechanism, to avoid damaging this very thin lens.

Operational setup/scheduling. I would anticipate that surgeons who perform cataract surgery would simply add these cases onto their normal surgical day(s). The two procedures require very similar setup arrangements in terms of preoperative preparation, dilation, topical anesthesia, a sterile environment, and postoperative medications and care.

Those who do laser surgery may be accustomed to refractive surgery scheduling blocks and specific refractive staff, but the time-opportunity cost of adding these refractive patients to an existing cataract block is so low that it makes more sense.

I have found it quite easy to simply intersperse phakic IOL patients with cataract patients on my regular cataract surgery day, without any disruption to patient flow or OR turnaround. The only significant difference in the cases is that I have a separate instrument tray with the instruments that I want to use for a phakic case. This tray doesn't include the capsulorrhexis forceps or cystotome I would use for phaco, so it also serves as a safety check against doing an accidental phacoemulsification.

If phakic procedures are to be done in the office, significant challenges exist in developing a sterile OR-like facility, and in training staff on sterile procedures. For this reason, most surgeons will be more comfortable doing the procedure in an ambulatory surgical center (ASC) setting.

Positioning within the practice. Practices need to think about all the places in which they talk about LASIK or laser surgery in ads, signage, and promotional material, and consider changing the frame of reference to "refractive surgery." Will there be a big splash about the new procedure, or will phakic IOLs just quietly be added to the list of procedures performed? Regardless, all staff, and particularly the refractive surgery coordinator or counselors, will need training on the new procedure, how it compares with other refractive procedures, who are the best candidates, and how to answer patients' questions about phakic IOLs.

I find that patients are primarily concerned that this is a new procedure and it's unfamiliar to them. Most people know someone who had LASIK, or they've read about the procedure in the media or online, but they've probably never heard of a phakic IOL. Naturally, patients are going to want to know exactly how it works and what to expect from the procedure. It's a whole new concept that requires the same level of education that we had to do in the early days of corneal refractive surgery.

Marketing. Depending on how phakic IOLs are positioned, the practice may need to plan some phakic IOL-specific advertising and/or revise marketing literature. Again, I think this will have to be very educational in nature, as many good phakic IOL candidates have been told in the past that that they aren't candidates for refractive surgery. Once we have this new category of refractive correction available, the marketing challenge will be primarily to educate patients about how a phakic IOL works, not sell them on the procedure.

Fee structure. Finding a cost-effective way to do intraocular surgery for refractive purposes is going to be one of our toughest challenges. Intraocular (cataract) procedures now are virtually all covered by Medicare or private insurance, and typically performed at outpatient facilities that do their own billing.

But a phakic refractive implant will be a noncovered, elective procedure and we need to come up with a price that patients will find reasonable for an elective procedure. A single fee will probably be most appealing. That means surgeons will have to negotiate with their ASCs for use of the OR, anesthesia and disposables, and come up with a user fee that, along with the cost of the implant, can be folded into the final procedure price. This may create an additional financial incentive for surgeons to build their own ASCs, or do in-office intraocular procedures, despite the sterility challenges.

Ultimately, I view these steps as essential preparation for performing intraocular refractive surgery, not just phakic IOL surgery. I think phakic IOLs will be an important part of what a comprehensive practice is going to offer, but whether one believes in and successfully incorporates any given phakic IOL is irrelevant. The reality is that new developments in several lens categories -- phakic IOLs, refractive lens exchange, multifocal, accommodating and adjustable IOLs -- will mean that there are many cases in which an intraocular solution is not only viable, but preferable.

Once intraocular refractive surgery in some form has been incorporated into the practice, it becomes very easy to counsel each patient about which procedure is truly the best choice for him or her, based on age, refractive error, corneal topography, lifestyle and other factors. The trend towards offering intraocular solutions is a powerful one, I believe.

Positive Data Exists

Internationally, we have more than 10 years experience with both the anterior chamber Artisan and the posterior chamber ICL. Three-year data has been presented to the FDA, and with ongoing monitoring, the earliest U.S. ICL patients are now about 5 years out. Both lenses have been extraordinarily well-tolerated.

Ultimately, complications will really define the use of these lenses. The ability to put a lens in the eye to correct for a given refraction is well-accepted, so the decision about whether phakic IOLs are a viable surgical option rests on their long-term safety profiles. Given the data we have so far, I believe they will be accepted by surgeons and patients alike.

In the clinical trials, the incidence of cataract was similar for the Artisan and the ICL. Each had about a 2% cataract rate, with only three patients (<1%) in each study requiring cataract extraction. Neither was associated with pressure increases or glaucoma. Rates of postoperative inflammation and increase in refractive cylinder were low for the Artisan lens (1.3% and 3.5%, respectively) and low also in the ICL trial (none and 0.5%, respectively).

Endothelial cell loss was the greatest concern of FDA reviewers of both lenses. (See "Addressing Safety Concerns with Phakic IOls," on page 62). Given the concerns, there will probably be a preoperative minimum cell count requirement based on age, although it hasn't yet been determined how such an assessment would be done.

As is prudent and responsible, the manufacturers will continue to do post-approval monitoring of safety issues like endothelial cell loss, but individual surgeons aren't likely to have to perform burdensome cell count testing.

It's important to remember that cell loss is a theoretical risk. Until now, there's nothing to suggest that either lens will cause long-term cell loss, although we might expect some differences due to location of the lens. Proximity to the endothelium, with the potential for bump or touch of the cornea, may carry greater risk than lenses that are located away from the endothelium.

Other complications may also be design-dependent. The Artisan/Verisyse iris-clip lens can come loose if not properly attached. And decentration can be a problem if the lens isn't perfectly centered around the pupil.

With the posterior lens, the proximity of the lens to the pigment epithelium does lend itself to the possibility of iris pigment loss or transillumination defects, but the incidence of these in the ICL trial was only 1.2% and none of the cases was clinically significant. There's also the potential for crystalline lens touch and subsequent lenticular changes if the ICL vaulting is less than anticipated. This is rare, and in the majority of cases hasn't caused lenticular changes, but lens touch can occur due to sizing disparities. Determining proper sizing remains a point of continued development for the ICL.

But as the following summaries show, both the STAAR Visian ICL and the Artisan/Verisyse have demonstrated superior, safe performance in the vast majority of patients who've received these lenses, which bodes well for their acceptance once they're approved for wider use.

The STAAR Visian ICL

The Visian ICL has been through four iterations in recent years. With experience, there have been product innovations one might see with any implant, such as minor modifications to adjust for fit and vaulting, or clearance of the crystalline lens.

In a clinical trial of 526 eyes of 294 subjects, the mean refractive error was -10.1D, with a range of -3D to -20D. One third of the eyes had less than -8D of myopia. The average age was 36.5. Patients had to have an anterior chamber depth of at least 2.8 mm to qualify for the study.

At 3 years post-op, 81% of the eyes were 20/40 or better and 41% were 20/20 or better uncorrected. These data are complicated by the fact that a significant number (69%) of these highly myopic patients didn't have 20/20 BSCVA pre-op and/or were not targeted for emmetropia. The total cohort also included eyes with up to -2.5D of astigmatism.

Among those with pre-op BSCVA of 20/20 and who were targeted for emmetropia, 95% were 20/40 and 59% were 20/20 or better uncorrected. Approximately 60% of the eyes had post-op UCVA as good as or better than their preop BSCVA.

Patient satisfaction rates were very high, with 92% very or extremely satisfied. Only four patients expressed dissatisfaction at any visit during the 3 years. Almost all (97%) said they would have the procedure again.

About half of the patients gained one or more lines of BSCVA, compared with only 8% who lost one or more lines of acuity. Perioperative complications were reported for 17 eyes, the most common of which was removal and reinsertion of the ICL on the day of surgery. There were three retinal detachments. Secondary ICL surgical procedures were needed in 3% of eyes, including the three eyes that underwent cataract surgery.

The Artisan/Verisyse

Developed in the late 1970s in the Netherlands by Jan Worst, M.D., the Artisan/Verisyse has been implanted as a phakic IOL in about 100,000 patients worldwide, with relatively few problems. The Artisan phakic lens has undergone only one design change in its history -- a change in the optic profile in 1990. Ophtec and AMO are currently working to develop toric, hyperopic and foldable versions of the lens for the U.S. market.

One major U.S. clinical study of the Artisan/Verisyse encompassed 22 investigational sites, 30 investigators, 560 patients and 971 implants. To be included in the study, patients had to be between the ages of 21 and 50, have between -5D and -20D of myopia, and have less than or equal to 2.5D of astigmatism. Patients in the study had a mean refractive error of -12.60D, with an average age of 39.6 years. Sixty-four percent of the patients were women and 36% were men.

Patients' anterior chamber depth had to be at least 3.2 mm to allow room for the implant.

About 81% of the patients received the larger 6-mm optic implant. The highest myopes were implanted with the 5-mm optic.

At 6 months, investigators reported good visual outcomes in both best-corrected and uncorrected visual acuity. The outcomes showed 86% of eyes within 1D of intended correction and 61% within 0.5D of intended correction. Because the implants only were available in 1D increments, investigators noted that outcomes would probably be even more predictable if the lens were made in 0.5D increments.

Another report on the Artisan showed 94.7% of patients within 1D of their target correction after 3 years.

In data presented to the FDA Ophthalmic Devices Advisory Panel, overall patient satisfaction with the Artisan procedure was reported as more than 90%. Complications observed in the study were reported as relatively minimal and treatable, though some patients did experience postoperative halos.

Offer Intraocular Options

In sum, I see phakic IOLs as a safe and effective modality, first for the correction of moderate-to-severe myopia, with toric and hyperopic approvals not far behind. Ophthalmologists would be wise to start thinking now about how to incorporate into their practice models not only phakic IOLs, but many types of intraocular refractive solutions that will be approved in the coming years. Fortunately, the barriers to entry for performing these procedures are relatively low. Unlike LASIK, for example, no expensive equipment must be purchased upfront for phakic IOL implantation.

Regardless of which phakic lens you favor, being able to offer this option to patients, many of whom have no other option for refractive correction, will be a satisfying way to broaden your surgical armamentarium.

Dr. Vukich is Surgical Director at the Davis Duehr Dean Center for Refractive Surgery in Madison, Wis. He's a consultant to STAAR Surgical Company, and medical monitor for the company's U.S. FDA clinical trial, but has no financial interest in either lens. You can contact him at (608) 282-2002 or javukich@facstaff.wisc.edu.

How I Implant the Verisyse BY KERRY ASSIL, M.D.

For surgeons implanting their first Verisyse cases, specific attention should be focused on several details: 1. Because the Verisyse is the only IOL that can be truly centered relative to the entrance pupil, it's important to establish anatomical landmarks directing implantation so that the optic will truly reside centered relative to the entrance pupil, thus maximizing one of the inherent benefits of this IOL. The lens is fixed to the iris mid-periphery by incorporating a portion of the iris stroma into a gap in the haptics. Perilimbal ink markings placed in the horizontal meridian just prior to entering the eye serve as useful centration landmarks, as they remain stationary when the pupil moves (following entry of the eye or infusion of viscoelastics). 2. The Verisyse lens is also unique with respect to fixation technique, with its haptics grasping mid-peripheral anterior iris stroma. This process, referred to as enclavation, can be performed in several easy steps, including the placement of two paracentesis sites approximately 11 mm apart in chord length placed at the two and ten o'clock hemi-meridia with the entry tunnel directed towards the four and eight o'clock positions respectively. This will facilitate the two-handed enclavation process, with the enclavation needle entering through the paracentesis site, while the surgeon's other hand holds the lens optic in place using fixation forceps. This single step, which perhaps draws the greatest degree of attention and scrutiny to the Verisyse lens, can be quickly mastered. For early cases, special attention should be paid to: placing a small amount of viscoelastic between the lens optic and corneal endothelium entering with the enclavation needle prior to grasping the lens optic and deciding whether you're more comfortable grasping the lens or the enclavation needle with the dominant hand for the initial haptic enclavation. 3. The current version of the Verisyse lens requires a 5- 6-mm entry site, which can most readily be performed utilizing a 3-mm keratome entry followed by infusion of a small amount of viscoelastic prior to enlargement using a 5- 6-mm keratome. This entry site may be closed with a single figure-8 10-0 nylon suture or 3 interrupted 10-0 bites. Future advances expected with the Verisyse include the Veriflex foldable lens, currently available in Europe, which can be inserted through a much smaller entry site, thereby minimizing concerns for chamber formation or the need for suturing.

Visian ICL Implantation: Five Steps to Success BY STEPHEN G. SLADE, M.D.

1. Peripheral iridotomies (PIs) are required to ensure unobstructed aqueous flow. Creating the PIs 1 to 2 weeks prior to surgery will ensure quiet eyes on the day of Visian ICL implantation. We suggest using the YAG laser or a two-step approach in which an argon laser is used as a pre-treatment followed by the YAG. Creating two PIs at approximately the 11 and 1:30 clock-hour positions will provide an outlet for aqueous flow around the lens. As the ICL deploys, visualizing the orientation indicator on the leading right footplate ensures proper placement. 2. An accurate white-to-white measurement is necessary for appropriate sizing of the Visian ICL. Our preferred technique is to recline the patient and instill a drop of topical anesthetic. Using calipers and magnification, measure the horizontal white-to-white. Verify the caliper measurement against a steel rule. The use of the Orbscan or topography can validate the caliper measurement. However, one needs to be careful with existing vessel beds and pterygiums as they can affect these devices. Always evaluate discrepancies between measuring devices, and remeasure if necessary. 3. Correct placement of the Visian ICL into its delivery cartridge is critical to a successful implantation. Verify the alignment of the orientation marks of the ICL with the cartridge landmarks. Carefully observe the ICL within the cartridge, ensuring that a smooth appearance and no folds are present. 4. Patience and a delicate touch during placement will ensure a complication-free Visian ICL procedure. Go slowly as the lens is delivered, allowing the leading footplates to deploy before completely releasing the ICL from its cartridge. As the leading footplates deploy, observe the orientation marks and their correct placement. When tucking the footplates behind the iris, never cross the central visual field with an instrument. 5. Complete viscoelastic removal is accomplished by manual flushing of the anterior chamber. BSS is delivered through a cannula attached to a syringe. The Visian ICL is implanted through a 3.0-3.2-mm, temporal, clear-corneal incision, oriented to the iris plane. Slight incisional pressure while irrigating may be required to facilitate complete viscoelastic removal through this small incision.