Sometimes, in refractive surgery, the whole is greater than the sum of its parts. This is the case with the bioptics procedure. By combining the implantation of a phakic intraocular lens with a corneal procedure such as LASIK, a surgeon can actually obtain a more predictable, accurate visual result than would be possible with either procedure alone. When phakic IOLs are approved in the United States, you should work with them for a while to gain experience. Then, when you feel comfortable with your technique, consider offering bioptics to your highly myopic patients. Here is my bioptics technique, and details on the results I’ve been able to achieve with it after 400 cases.

Bioptics’ Background and Goals
Though bioptics can be unplanned, as in the case of a cataract extraction with residual refractive error,1 this article deals with planned bioptics. This variety is usually aimed at treating patients with refractive errors that are too high to be treated with one procedure. It was developed by Argentina’s Roberto Zaldivar, MD, to deal with the technical limitations that restrict IOL powers to approximately -20.5 D.2,3

I perform bioptics on myopes whose refraction is at least -14 D.4 To understand the benefit of bioptics, it’s helpful to consider what would occur if we could only perform one procedure on such patients.
LASIK would be out of the question immediately; when it’s used on anyone

The bioptics procedure combines phakic intraocular lens implantation with LASIK to correct high myopic refractive errors while preserving an ample optical zone.

above around -8 D, its predictability deteriorates. Also, and probably more importantly, the optical zone necessary to correct that much error is so small relative to the pupil’s size in low light conditions that there’s a greatly increased risk of night glare and halos.

If we used just a phakic IOL, we couldn’t correct more than -12 D to
-13 D, because, as the lens power increases, its optical zone size decreases. At levels above these, the optical zone size of the lens would result in more qualitative visual complaints at night. Ideally, we’d want to preserve about a 6-mm to 6.5-mm zone. That’s what bioptics allows.

The Procedures
 • Lens implantation. Since I have the most experience with implanting the Artisan phakic lens (Ophtec, Groningen, The Netherlands; Ophtec U.S.A., Boca Raton, Fla.) for bioptics, that’s the implantation technique on which I’ll focus.

A good preop endothelial cell count and measurement of anterior chamber depth are necessary. I avoid operating on patients with cell counts below 2,000 cells/mm2 and anterior chambers shallower than 3.2 mm.

Selecting the dioptric power of the lens is easier with bioptics, because any

Enclavating the iris through the Artisan’s haptic holes is the most challenging step. The 30-ga. enclavation needle helps the surgeon gather a bit of iris tissue and enclave it in one of the holes.

residual refractive error will be corrected with LASIK. I usually limit the lens’s correction to -15 D.

To begin the procedure, I administer a retro/peribulbar block (4 ml of a proportional mixture of mepivacaine 2%, bupivacaine 0.75% and mucopolisacaridase).

In patients for whom I’ll be planning a customized, topography- or wavefront-linked ablation with topography or wavefront analysis, I’ll make the corneal flap before I start the implant procedure.4 This way, I can study the surface changes induced by the flap several weeks before the ablation and compensate for them later in the LASIK. Otherwise, I’ll just leave the flap creation until the LASIK procedure later.

I mark the main incision site at 12 o’clock, then place marks at 10 o’clock and 2 o’clock; these last two will be the sideport incisions. If the lens to be inserted is a toric model that’s currently available outside the United States, I’ll also mark the axis of astigmatism on the limbus.

First, I make a 6.2-mm, two-plane incision in the cornea at 12 o’clock. I then make the two vertical sideport incisions.

I inject viscoelastic and acetylcholine. The challenge here is to inject the viscoelastic at a consistent rate to keep the iris in the same position that it was in at the slit lamp or a bit convex. This facilitates the iris enclavation step, which comes later, and protects the endothelium. I try to inject the viscoelastic slowly with the needle in the periphery. If you inject  it too vigorously in the center, this can cause anterior chamber vacuoles to form or the pupil to dilate, which is undesirable.

Next, I insert the lens into the anterior chamber, then rotate it with a hook or with the viscoelastic cannula. A cyclodialysis spatula, inserted through one of the sideport incisions, ensures the lens doesn’t touch the endothelium as I rotate it 90 degrees to a horizontal orientation. This precaution isn’t usually necessary, however, especially in myopes.

The most challenging step is enclavating the iris. For this maneuver, the surgeon bunches mid-periperhal iris into the fixation holes on either side of the lens’s optic. This bunching of iris holds the lens in place. I strongly urge anyone who wishes to perform bioptics to attend several courses on the techniques involved with iris enclavation with the Artisan, as it is a step that’s best learned in a hands-on environment.

I accomplish the enclavation by inserting the lens forceps through the main incision with one hand, without actually grasping the optical part of  the lens. Then, I insert the blunt, 30-ga. enclavation needle through the corresponding sideport incision. I grasp the lens with the forceps, pushing it slightly posterior, and try to bunch up a small “knuckle” of iris and enclave it in one of the holes in the haptic with my other hand. If it’s indeed centered correctly over the pupil and in the correct axis of astigmatism, I switch hands and repeat the enclavation for the other side. When both haptics are fixated, I perform a slit iridotomy at 12 o’clock to prevent a postop intraocular pressure spike that can be caused by pupillary block.

I close the incision with five or six single 10-0 nylon sutures with minimal tension, and then use a bimanual irrigation-aspiration technique to exchange the

Once the Artisan lens is situated in an eye, I usually wait about three to four months for the refraction to stabilize. Then, I move on to the LASIK step.

BSS for viscoelastic. Postop medication includes tobramycin-dexamethozone q.i.d. for the first 15 days, tapering it over the following week. At the four-week mark, I remove the sutures.

It takes about three to four months for the refraction and the topography to stabilize. I want to see two identical topographic maps about three weeks apart before I’ll perform the LASIK procedure. 

 • LASIK. This corneal surgery will correct the remaining refractive error, usually between -4 D and -8 D.

Originally, when my colleagues and I started performing bioptics with an anterior chamber lens, we were concerned that there might be corneal endothelial problems associated with using the microkeratome while the lens was affixed in the anterior chamber. Because of this, we would make the flap at the time of lens implantation just before the lens was implanted. Then, when it came time for the LASIK several months later, we’d just relift the flap. Since then, though, we’ve discovered that it makes no difference when you make the flap, as the endothelium remains safe either way.

The LASIK step proceeds normally under topical anesthesia. I use a 6-mm optical zone with a transition zone extending out to 9 mm.

What to Expect
 • The benefits. Though I’ve performed around 400 bioptics cases, I’ve only studied 74 in a prospective fashion. The results have been good, however. Only part of these results have been published.5,6

At two years, the patients’ average spherical equivalent refraction diminished from -18.42 D to just -0.38 D. All of the patients are within 1 D of emmetropia, and 80.7 percent are within 0.5 D of it. Seventy-seven percent see at least 20/40 postop, and, while 42 percent of patients gained two or more lines of best-corrected vision, none lost two or more lines.

Results with a posterior chamber lens, the Staar Implantable Contact Lens (Staar Surgical, Monrovia, Calif.), are comparable. In a study of 67 eyes undergoing bioptics with the ICL, the spherical equivalent refraction decreased from an average of -23 D preop to -0.20 D at three months postop. Eighty-five percent of the eyes were within 1 D of emmetropia, 76 percent gained two or more lines of best-corrected vision, and no eyes lost two or more lines.2 These results improved upon those with Artisan lenses with 5-mm optics, which usually leave some myopia.

We expected such quantitative results, however. It’s in the realm of the qualitative that bioptics shows its true benefits. When compared to LASIK performed in high myopes, in which 100 percent of patients usually experience some form of glare or halo at night, only 18 percent of our patients complained of problems with night driving.

 • The drawbacks. Fortunately, significant complications haven’t appeared in our experience. In my prospective study, three lenses had to be removed due to subluxation, and there were three flap complications: a free cap, a flap that dislocated due to trauma a day after surgery and an irregularly short flap. Endothelial cell counts of all my cases, which are out as far as six years, are similar to normal human physiological counts without surgery. I think we need at least four more years before we consider it totally safe for the endothelium, however.

Though we didn’t experience them, other complications related to Artisan implantation are as follows:

• a 4.5-percent incidence of wound leak;

• posterior synechiae in just under
2 percent of patients in anterior chambers shallower than 3.2 mm;

• a 5- to 10-percent incidence of pigment dispersion, which resolves in about six months;

• An approximate 1.5-percent incidence of postop IOP increase, manageable with the creation of a sideport paracentesis and a 24-hour course of Diamox; and

• chronic subclinical iritis related to surgical trauma in about 29 percent of patients, treatable intraoperatively with triamcinolone or postoperatively with topical steroids and cycloplegia.7

According to Tijuana’s Arturo Chayet, MD, who’s implanted 300 ICLs, complications associated with ICL implantation include:

• a 1- to 2-percent incidence of the IOL’s being implanted upside down, which is related to inexperience with the lens;

• a 2-percent rate of pupillary block on postop day one, due to small iridotomies or viscoelastic plugging the iridotomies;

• retinal complications, specifically macular hemorrhage and retinal detachment, in less than 1 percent of patients in the first postop month;

• a 1- to 2-percent incidence of pigmentary glaucoma as a result of the iris’s rubbing against the anterior surface of the ICL;

• a 10-percent rate of occurrence of subclinical cataract, mainly due to inexperience with the lens; and
• around a 1.6-percent incidence of cataract requiring extraction, usually due to intraoperative trauma.

There is also a new complication that bioptics may introduce: optical aberrations due to two optical systems’ having to work together. To date, this possible disadvantage hasn’t been thoroughly studied, though we’ve gained enough experience that we can propose an explanation. The risk is probably higher if you use a toric phakic lens. If you center the lens properly and don’t decenter the laser ablation, however, you can minimize the possibility that the patient will experience aberrations.

Though phakic lenses are still not approved for sale in the United States, surgeons will eventually gain experience with them. When they do, even the most miserable myopes will have a procedure that can give them the predictability and quality of vision enjoyed by refractive patients with more mild nearsightedness.  

Dr. Güell is an associate professor of ophthalmology at University Autonoma in Barcelona.

1. Güell JL, Gris O, Muller A, Coscostegui B. LASIK for the correction of residual refractive error from previous surgical procedures. Ophthalmic Surg and Lasers 1999;30:341-349.
2. Zaldivar R, Davidorf J, Oscherow S, Ricur G, Piezzi V. Combined posterior chamber phakic intraocular lens and laser in situ keratomileusis: Bioptics for extreme myopia. J Refract Surg 1999;14:294-305.
3. Zaldivar R, Davidorf J, Oscherow S. Posterior chamber phakic intraocular lens for myopia of –8 to –19 diopters. J Refract Surg. 1998;14:294-305.
4. Güell JL. The Adjustable Refractive Surgery Concept (ARS). Letters to the Editor. J Refract Sur 1998;14:271
5. Güell JL, Vazquez M, Gris O. Adjustable refractive Surgery: 6 mm Artisan Lens plus laser in situ keratomileusis for the correction of high Myopia. Ophthalmology 2001;108:5:945-952
6. Güell JL, Vazquez M, Gris O, et al. Combined surgery to correct high Myopia: Iris Claw Phakic Intraocular Lens and laser in situ keratomileusis . Journal refract Surgery 1999;15:529-537
7. John M. The art of the artisan phakic IOL. Review of Ophthalmology 2001;8:8:88-89.