Michael C. Knorz, MD
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When assessing the armamentarium of a practicing refractive physician, it is impossible not to consider using a phakic IOL.
Of those available on the market, the iris supported Verisyse IOL (Advanced Medical Optics) has the longest track record.
It has been FDA approved and on the market in the US for more than a year now. I have personally used this lens in my practice
for eight years with successful outcomes and have recommendations for others on my preferred technique as well as how to manage
potential complications when using phakic IOLs.
When considering which patients would benefit from a phakic IOL, I tend to select those with high myopia; -8 D or higher,
with an anterior chamber depth of at least 3.2 mm. In patients with thin corneas (<500 µm), I consider using a phakic IOL,
even in myopia of –5 D or higher. I also consider patients with high hyperopia as excellent candidates for an iris-supported
anterior chamber phakic IOL. For these patients, I would consider those who were +4 D or higher if the anterior chamber depth
is 3.2 mm or more in patients younger than 40 years old; for older patients, I would consider refractive lens exchange and
implantation of a multifocal IOL (e.g., ReZoom, Tecnis multifocal) as a better option.
The implantation technique
The implantation technique that I find useful in minimizing the amount of induced astigmatism is the "frown-incision"; a scleral
tunnel incision still familiar to those who performed phacoemulsification in those days when a foldable IOL was not available.
I first inject Lidocaine 1% under the conjunctiva at 12'o clock. Then, I open the conjunctiva at the limbus and use bipolar
cautery to minimize bleeding.
Next, the frown incision is performed, creating a 6 mm scleral tunnel which is, in most cases, self-sealing, although I prefer
to add a suture to play it safe.
In short...
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Before I open the anterior chamber at the site of the frown incision, I create two side-port incisions at 3 and 9 o'clock
at the limbus. The incisions should be rather steep towards the iris and not parallel to the iris as in phacoemulsification.
The reason is that the iris has to be grasped through these incisions with iris enclavation forceps. I inject lidocaine 1%
at each of the side-port incisions to avoid any pain during enclavation. Next, I inject Miochol (acetycholine), rather than
lidocaine, which has a mydriatic effect. Finally, Healon GV is injected and the main incision (the frown incision) is opened.
The phakic IOL is now implanted into the anterior chamber and rotated into the horizontal position prior to enclavation.
For enclavation, I prefer the dual-forceps technique; holding the phakic IOL with holding forceps and grasping the iris with
iris forceps. I then push the haptic of the IOL over the iris forceps, thereby enclavating the iris. I then re-grasp the iris
just beneath the enclavation site and push the haptic over the forceps again to increase the amount of iris tissue enclavated.
After enclavation, I perform a small surgical iridectomy at 12 o'clock. Because of the tunnel incision, the iridectomy is
not very peripheral, but usually still covered by the upper lid. Finally, I use a 10-0 nylon running X-suture, wash out the
Healon GV with BSS, and tie the suture. The conjunctiva is closed with a single 10-0 nylon suture.
Postoperatively, I use a combination of dexamethasone and tobramycin three times daily for one week and pred forte twice daily
for four weeks. The conjunctival suture is removed after one week, the scleral suture is usually left in place but cut at
three to four weeks in case it induces an astigmatism of more than one diopter.
