Conductive keratoplasty for the correction of low to moderate hyperopia: 1-year results on the first 54 eyes.
OBJECTIVE
To document the 1-year postoperative clinical results of the safety, efficacy, and stability of conductive keratoplasty (CK) to correct low to moderate hyperopia.


METHODS
Prospective, nonrandomized, self-controlled trial.


METHODS
Five surgeons at four centers performed CK on the first 54 eyes of a multicenter, 2-year clinical trial. Treated eyes had +0.875 to +4.00 diopters (D) of hyperopia and < or =0.75 D of cylinder. The nature of this procedure was explained to all participating patients who signed informed consent forms prior to undergoing the procedure.


METHODS
Low energy, high-frequency current was applied directly into the peripheral corneal stroma through a delivery tip inserted at 16 or more treatment spots. An early nomogram was used for the first 54 eyes with an intended refraction of plano.


METHODS
Data from all 54 eyes were analyzed for safety and stability. A subset of 30 of the 54 eyes was found that had been treated with the appropriate number of spots with the early nomogram. These eyes were categorized as current nomogram eyes; the data for these eyes were analyzed for efficacy and predictability, as well as stability and safety. All patients reported on satisfaction and quality of vision after surgery.


RESULTS
Preoperatively, the manifest refractive spherical equivalent refraction (MRSE) of the 30 current nomogram eyes was +1.57 D. At 1 year postoperatively, uncorrected visual acuity was 20/20 or better in 57% of the eyes and 20/40 or better in 93%. The MRSE was within 0.50 D in 46%, within +/-1.00 D in 93%, and within +/-2.00 D in 100%. No eye lost > or =2 lines of best spectacle-corrected visual acuity at 1 year postoperatively nor had an induced cylinder of > or =2.00 D. The MRSE changed a mean of 0.25 D +/- 0.43 between 3 and 6 postoperative months, 0.16 D +/- 0.38 between 6 and 9 postoperative months, and 0.07 D +/- 0.38 between 9 and 12 postoperative months. Refractive stability appeared to be attained by 6 months postoperatively.


CONCLUSIONS
Conductive keratoplasty appears to be safe, effective, and stable for correcting low to moderate spherical hyperopia. Stability appeared by the 6-month follow-up visit. For the eyes treated with the current CK nomogram, uncorrected visual acuity, predictability, and stability are as good as or better than those obtained with hyperopic laser in situ keratomileusis or noncontact laser thermal keratoplasty.
McDonald
Marguerite B
MB
Southern Vision Institute, 2820 Napoleon Avenue, New Orleans, LA 70115, USA.
Davidorf
Jonathan
J
Maloney
Robert K
RK
Manche
Edward E
EE
Hersh
Peter
P
D000328:Adult; D000368:Aged; D000818:Animals; D003319:Corneal Stroma / Q000503:physiopathology / Q000601:surgery*; D016039:Corneal Transplantation / Q000379:methods; D004564:Electrocoagulation / Q000379:methods*; D005260:Female; D006801:Humans; D006956:Hyperopia / Q000503:physiopathology / Q000601:surgery*; D007429:Intraocular Pressure; D008297:Male; D008875:Middle Aged; D017060:Patient Satisfaction; D011182:Postoperative Care; D011446:Prospective Studies; D012449:Safety; D013552:Swine; D016896:Treatment Outcome; D014792:Visual Acuity