CK technique focuses on presbyopia

Columbia, SC-The Light Touch technique of conductive keratoplasty (CK, Refractec), developed by refractive specialist Henry L. "Rick" Milne, MD, shows promise in the correction of near vision in patients with presbyopia, explained Dr. Milne.

Dr. Milne, affiliated with The Eye Center, Columbia, SC, reported on the preliminary findings of an FDA prospective, multicenter clinical trial of 125 patients who underwent this off-label technique, which involved the treatment in the non-dominant eye only. The Light Touch technique, which is widely used off-label in clinical practice, involves minimal corneal compression of about 2 mm at the time of application of the radiofrequency probe. This technique offers less treatment variability, a better response, and less risk of induced cylinder, he explained.

Four clinical investigators are involved in the 12-month study: Dr. Milne, Columbia, SC; Daniel Durrie, MD, Overland Park, KS; Michael Gordon, MD, San Diego; and Peter Hersh, MD, Hackensack, NJ. Patients were included in the study if they had tolerated contact lens monovision in the past or had tolerated it for 1 week with or without achieving monovision. The preoperative manifest refractive spherical equivalent was required to be between +1 to –0.50 D with less than 0.75 D of cylinder. Peripheral pachymetry had to be greater than 560 μm, Dr. Milne said.

Dr. Milne presented the 1-month results of 88 patients who underwent Light Touch CK for presbyopia. The mean patient age was 51 (range, 41 to 68) and 65% were female. The mean intended correction was –1.88 D with a range of –1.00 to –2.25 D.

In terms of safety, no eyes lost greater than 2 lines of best spectacle-corrected visual acuity for distance and no eyes had more than 2 D of induced cylinder. There were no adverse events or complications associated with the procedure, Dr. Milne reported.

The treatment response at 1 month postop was favorable with three patients who underwent the eight spots at 8 mm, achieving –1.21 D. Thirty-six patients treated with eight spots at 7 mm achieved –1.54 D and 49 patients treated with 16 spots at 7 and 8 mm achieved –2.49 D, he explained.

The investigators were also pleased with the accuracy of the CK procedure at 1-month postop, with 66% of the patients within ±0.50 D of attempted correction and 88% within ±1.00 D. In this patient population, 88% achieved < J1, 94% < J2, and 97% saw < J3, Dr. Milne said.

"Binocular uncorrected visual acuity for distance remained unchanged from preop to postop," Dr. Milne noted. "Binocular distance and near vision was 20/20 and J3 in 86% of these patients and 20/20 and J1 in 79% of these patients, which are quite good results."