Technology Spotlight / INSIDE THE EYE : Foldable Lens Eases Cataract Treatment

Cataracts rob millions of Americans, mostly the elderly, of their sight by clouding the lens inside the eye. The only way to treat the problem is to remove the natural lens and replace it with a plastic substitute.

A type of soft, foldable lens replacement, developed by Allergan Inc. of Irvine, allows doctors to remove and replace a patient’s lens without hospitalization in as little as 20 minutes. Most patients recover their sight in a few weeks, instead of the two to six months required with hard plastic lenses.

The key is in the size of the incision, which is 20% to 60% smaller for the foldable lens.

Allergan has had a foldable lens on the market for nearly two years, and last month the U.S. Food and Drug Administration granted approval to Chiron Ophthalmics, also in Irvine, and Staar Surgical Co. in Monrovia to sell foldable lenses.

Although the number of lens implants has declined slightly due to a recent change in Medicare policy limiting reimbursements for cataract surgery, the aging of the general population is expected to result in increasing demand for foldable lenses.

Cataract Removal: High-frequency ultrasound pulverizes the natural lens, which is then suctioned out of the eye. The pocket where the lens implant will be placed is then stretched with a gel substance.

Implantation: The soft, silicone lens is folded in half and inserted through a tiny incision, about 4 millimeters across, near the edge of the iris.

Final Placement: The lens is unfolded and secured with a pair of spring-like wires, called haptics. The incision is stitched closed, and the eye is bandaged for 24 hours. INTRAOCULAR LENS MARKET

in millions

Implants 1992*: 1.39 Revenues

1992*: 312.8 FOLDABLE LENS MARKET FORECAST*

in thousands Implants 1995*: 630 Revenues

1995*: $126 * Projected figures.

Source: Allergan Inc., Chiron Ophthalmics

Researched by DALLAS M. JACKSON / Los Angeles Times