Wavefront guided enhancements assist in treating complications

BOSTON — Wavefront-guided enhancement can be an effective treatment for many corneas with irregular shapes resulting from previous refractive surgery, according to one speaker here. The custom treatments can be especially effective when used with small laser spot size, accurate registration, a good eye tracker and a wide treatment zone, Roger F. Steinert, MD, said.

Dr. Steinert discussed issues and limitations associated with wavefront technology at the American Society of Cataract and Refractive Surgery Summer Refractive Congress. He noted that while wavefront technology is widely used for enhancement procedures, researchers have had inconsistent results using the technology on optically challenged corneas.

"Wavefront algorithms are optimized for primary treatments, where the low-order aberrations, sphere and cylinder are much larger than the higher-order aberrations," he said.

Dr. Steinert presented several cases in which patients with previous refractive surgery were treated with wavefront-guided corrections. In one case, a 40-year-old woman underwent LASIK that was complicated by a microkeratome pass that stopped short nasally. The surgeon applied laser ablation without shielding the underside of the flap. When the flap was replaced, the patient had high coma, an untreated mid-periphery and a doubly ablated central optical zone, Dr. Steinert said.

In the enhancement, a wavefront-guided PRK was performed on the flap, ablating to a central depth of 19.1 µm, he said.