San Diego-An evaluation of the first group of patients to undergo conductive keratoplasty (CK) performed by Ronald Friedman, MD, indicates that the procedure can be safely used to treat hyperopia and presbyopia and is easily introduced into an average-volume practice with a refractive and cataract base.
Of the 50 eyes, six had undergone a previous LASIK procedure and one had undergone a cataract extraction. All eyes had 20/20 vision preoperatively and were disease free. The average patient age was 54 years (female to male ratio: 3:1).
When he started performing CK, Dr. Friedman mostly did eight-spot treatments, which reflected his initial conservatism with the procedure and the relatively large number of patients who had undergone a previous LASIK procedure.
When evaluating his results, he looked at the change in refraction achieved, the enhancement rate, the complications that developed, and patient satisfaction.
"When we looked at the refractive change resulting from the eight-spot treatment, most patients achieved between 0 and 1.5 D of correction," Dr. Friedman reported. "When the eyes that had undergone LASIK were eliminated from the evaluation, the amount of the refractive change decreased substantially to 0.75 D, although a large number of eyes still achieved more than that.
"When considering the 16-spot treatment, there was an even distribution of correction among all the achieved ranges; this did not change significantly when the eyes that had undergone LASIK were removed," he added. "Slightly less than half of those eyes received the intended correction of 1.25 D. The eyes that underwent the 24-spot treatment all achieved more than 0.75 D of correction, and only one eye in this group achieved more than the intended 1.75 D of correction."
Regarding near vision postoperatively, all eyes could read J7 or smaller, and most eyes had J1 to J3 vision.
The level of induced astigmatism was greater than 1 D in four eyes 1 week after the surgery and in six eyes 1 month after surgery. Most of these eyes required an enhancement procedure because the induced oblique, or with-the-rule, astigmatism was not tolerated well, Dr. Friedman pointed out.
"Enhancements were performed on eight of the 50 eyes because of undercorrection; most of these eyes [originally] had an eight-spot treatment. Four eyes had an enhancement procedure because of induced astigmatism," Dr. Friedman reported. "Overall, 24% of the 50 eyes had an enhancement procedure, which was performed 1 month after the initial procedure. The enhancements done to correct induced astigmatism consisted of the placement of one or two spots guided by the results of topography and wavefront analysis."
Overcorrections occurred in three eyes, keratitis developed in three eyes, and iritis developed in two eyes, the latter two of which required treatment with topical steroids. No patient lost best spectacle-corrected visual acuity.