Toric phakic IOLs predictable, safe for use in previous PK, DALK eyes

STOCKHOLM, Sweden — Implanting toric phakic IOLs may be a safe, reliable surgical option for correcting refractive errors in phakic and aphakic patients previously treated with corneal grafting procedures, according to a study presented here.

José Güell, MD, and colleagues in Spain reviewed outcomes for 14 phakic and 10 aphakic eyes implanted with the Verisyse (Advanced Medical Optics) toric phakic IOL to correct moderate to high residual spherical and astigmatic errors after previous penetrating keratoplasty or deep anterior lamellar keratoplasty (DALK).

Dr. Güell discussed the results at the European Society of Cataract and Refractive Surgeons meeting.

"This lens provides good centration, stable fixation, safe distance from the endothelium and it is small and foldable, which means it can be implanted through a small incision, thus avoiding further induction of astigmatism," Dr. Güell said.

In all cases, implantation of the toric phakic IOL produced an increase in visual acuity of several lines. Spherical equivalent decreased to near plano from an average of -6 D to -5 D preoperatively. The astigmatic error also had progressively decreased during follow-up to a maximum of 1.25 D, he said.

Patients experienced rates of endothelial cell loss similar to the rates reported for all Verisyse phakic IOLs, with a 6% to 7% reduction at 3 years.

Dr. Güell noted that evaluating the reference axis both preoperatively and intraoperatively is mandatory because even small displacements can produce an undercorrection or even an increase in the astigmatic error.

Modern imaging technologies, such as the Visante anterior chamber OCT (Carl Zeiss Meditec), also provide valuable support in evaluating the lens performance during follow-up. Central and peripheral anterior chamber depth, as well as the distance of the IOL from the endothelium and from the crystalline lens should be measured at least once a year, he said.

"These toric [phakic] IOLs are, in my opinion, the best method for correcting medium-high ametropia after corneal transplantation," Dr. Güell said. "[The lenses] create predictable and stable vision and have the advantage of being a reversible procedure. In these eyes, I much prefer them to laser refractive surgery."