Preliminary results reported for Tetraform phakic IOL

Short-term results with the Tetraform phakic IOL (Lenstec) implanted in eyes for the correction of high myopia indicate this anterior chamber lens is promising technology, said Donald R. Sanders, MD, PhD.

The IOL is a single-piece, hydrophilic device with four-point fixation that can be delivered through a 1.8-mm incision. The first four implantations were performed by Juan F. Batlle, MD, at his eye center in Santo Domingo, in August 2005.

Slit-lamp examinations performed on the first day after surgery showed the eyes were consistently clear. Gonioscopy was done at 1 month post-implantation and showed that the implant's footplates were appropriately positioned in the angle. Scheimpflug imaging (Pentacam) demonstrated adequate clearance between the implant and the iris posteriorly and the peripheral and central corneal endothelium anteriorly.

Preoperatively, the eyes had SE values ranging from -11 to -12.375 D (mean -12 D) and best-corrected visual acuity (BCVA) ranging from 20/32 to 20/50. Results from follow-up performed at 4 months showed best spectacle-corrected visual acuity (BSCVA) was unchanged in one eye, had improved by one line in one eye and by two lines in two. Compared with the preoperative BSCVA, postoperative uncorrected visual acuity (UCVA) was better by 1 or 2 lines in three eyes and worse in one eye with a +1.5 D hyperopic. Postoperative BSCVA was unchanged compared with the preoperative level in that latter eye.

"Improvement in postoperative UCVA compared with preoperative BSCVA is a characteristic of good quality phakic IOLs," Dr. Sanders said. "We are now expanding enrollment in this study and will be starting a clinical trial in the United States to further evaluate the efficacy and safety of this investigational device."