Wavefront-optimized treatment helps irregular corneas

An excimer laser system (Allegretto Wave Eye-Q, WaveLight Inc.), which offers a 400 Hz ablation rate, can safely correct corneal irregularities, such as those seen in patients previously treated with small optical zones or decentered ablations. The system also can correct primary astigmatism and has been used in eyes with keratoconus awaiting corneal transplant, explained David T. Lin, MD, at a breakfast session sponsored by WaveLight.

Dr. Lin, of Vancouver, British Columbia, described several cases in which topographic-guided vision correction with this system was useful. He showed the optical zone enlargement of a patient who had been previously treated with four RK incisions. In another case, a patient with asymmetrical astigmatism after a wavefront-guided procedure had improvement in vision after the topographic-guided treatment. Decentered ablations were re-treated with the excimer laser system in 34 eyes and only one patient lost 1 line of best-corrected visual acuity.

In the keratoconus cases, 16 eyes awaiting corneal transplant were treated with transepithelial topographic-guided PRK with the excimer laser system, selectively treating the steep area and steepening the flat area. Little haze occurred, Dr. Lin said.

During the session, other presentations from users included patient flow, enhancement, and clinical realities by Anthony J. Kameen, MD, Baltimore; successful cyclotorsion control with Neuro Track (not available in the United States) by Arthur Cummings, MD, Dublin, Ireland; global optimum: presbyopia treatments by Theo Seiler, MD, PhD, Zurich, Switzerland; and the Allegro Oculyzer (WaveLight) in practice (not available in the United States) by Matthias J. Maus, MD, Cologne, Germany.

Topographic-guided treatment works on irregular corneas such as in eyes that have undergone PRK, LASIK, and post-RK, he said. It can be used to treat primary astigmatism, optical zone enlargements, and decentered ablations.