Positive results seen at 12 months for laser persbyopia

April 15, 2005

New York—Laser presbyopia reversal (LAPR) is showing significant promise and patient satisfaction based on 12-month follow-up results from a U.S. phase II clinical trial, said Sandra C. Belmont, MD.

New York-Laser presbyopia reversal (LAPR) is showing significant promise and patient satisfaction based on 12-month follow-up results from a U.S. phase II clinical trial, said Sandra C. Belmont, MD.

The procedure involves the use of an infrared erbium:YAG laser (OptiVision, SurgiLight) fitted with a conical tip fiber to create eight radial incisions in the sclera via tissue ablation. It is designed to improve accommodation by expanding the scleral tissue in order to enhance the efficiency of the ciliary muscle and zonules.

Dr. Belmont, director of the corneal service, and associate professor of clinical ophthalmology, Weill Medical College of Cornell University, New York, spoke during the refractive surgery subspecialty day before the American Academy of Ophthalmology annual meeting.

Patients were able to read immediately after surgery, and at 12 months, the group demonstrated a statistically significant increase in near uncorrected visual acuity (UCVA), with 90% achieving J3 or better. In addition, 100% of eyes had >1 D increased amplitude of accommodation with a mean increase after 12 months of about 2.4 D when measured by push-up and blur and a maximum increase of 3.25 D. One patient with a poor 12-month near vision outcome had resumed spectacle wear. Safety was favorable with no changes in IOP, axial length, or corneal topography, and patients have been very happy with the results.

"Expanded U.S. trials are needed, with longer follow-up. However, these early data mirror the results from international studies that involve several hundreds of patients and show minimal regression during follow-up extending to 4 years," she said.

Dr. Belmont is the principal investigator of the study. Jon Siems, MD, is the second investigator and has treated patients in his private practice in Las Vegas.

The laser used for the surgery has an output energy of 20 mJ, operates at a frequency of 20 Hz, and has a spot size of 400 µm. LAPR is performed under topical anesthesia using 2% lidocaine gel applied preoperatively and topical 1% proparacaine delivered via a pledget to the sclera for 3 to 5 minutes during the procedure.

The eye is marked at 6 and 12 o'clock with the patient in the sitting position, and four fornix-based triangular peritomies are made at 1:30, 4:30, 7:30 and 10:30. Wet field cautery is applied as needed.

The eight radially oriented ablations are made in the scleral tissue 0.5 mm posterior to the limbus. They measure 4.5 mm in length and are placed two per quadrant and spaced 2.5 mm apart. The depth of the ablation is about 80% of scleral thickness, and the appearance of the dark blue hue of the choroid marks the treatment endpoint.

The peritomy sites are closed with a bipolar forceps and topical treatment with a nonsteroidal anti-inflammatory agent and antibiotic is administered.

"The procedure takes about 45 minutes per eye, but it is easy to learn," Dr. Belmont said.

A postoperative evaluation performed at 1 hour after the surgery includes examination at the slit-lamp to verify complete conjunctival closure, IOP measurement, and a check of UCVA at 14 inches. In addition, patients are instructed to use the eyes for reading on an hourly basis and to continue their nonsteroidal anti-inflammatory drug and antibiotic treatment for 1 week after surgery.

"Over the longer term, it is important to make sure that patients exercise their eyes to read at a new focal length and do not return to wearing their glasses or they will lose the effect," Dr. Belmont said.