Two-year results of conductive keratoplasty for the correction of low to moderate hyperopia

J Cataract Refract Surg. 2003 Dec;29(12):2339-50. doi: 10.1016/j.jcrs.2003.09.022.


Purpose: To evaluate the 2-year postoperative safety, efficacy, predictability, and stability results of conductive keratoplasty (CK) to correct low to moderate hyperopia.

Setting: Department of Ophthalmology, Stanford University Medical Center, Stanford, California, USA.

Methods: In a prospective nonrandomized noncontrolled trial, 25 eyes of 14 patients with +0.75 to +3.00 diopters (D) of hyperopia and </=0.75 D of cylinder were treated with CK. Low-energy, radio-frequency current was applied to the peripheral corneal stroma through a probe inserted at 8 to 32 treatment spots. An early nomogram was used in 2 eyes, and a current nomogram was used in 23 eyes; the intended refraction was plano. The 23 eyes treated with the current nomogram were analyzed for efficacy, predictability, and stability. All 25 eyes were included in the safety and patient-satisfaction analyses.

Results: Preoperatively, the mean manifest refraction spherical equivalent (MRSE) in the 23 current-nomogram eyes was +1.55 D. At 2 years, the uncorrected visual acuity was 20/20 or better in 64% of eyes and 20/40 or better in 95%. The MRSE was within +/-0.50 D in 64% of eyes, within +/-1.00 D in 91%, and within +/-2.00 D in 100%. No eye lost more than 1 line of best spectacle-corrected visual acuity or had an induced cylinder greater than 0.75 D. The mean MRSE of the cohort with all follow-ups was +0.48 D, which reflected a 29% regression from the intended plano and 43% regression from the 1-month postoperative overcorrection. The rate of regression appeared to be low and decreasing, +0.024 D per month between 12 and 24 months. A patient survey revealed improved quality of vision and a high level of satisfaction.

Conclusions: Conductive keratoplasty appeared to be safe, effective, and predictable for correcting low to moderate hyperopia. Mild hyperopic regression was observed; however, the rate of regression indicated by the mean change in MRSE per month was low and decreased over the 2-year follow-up. Longer follow-up may be necessary to further characterize the refractive stability of CK.

Publication types

  • Clinical Trial

MeSH terms

  • Aged
  • Corneal Stroma / physiopathology
  • Corneal Stroma / surgery*
  • Electrocoagulation / methods*
  • Female
  • Follow-Up Studies
  • Humans
  • Hyperopia / physiopathology
  • Hyperopia / surgery*
  • Intraocular Pressure / physiology
  • Intraoperative Complications
  • Male
  • Middle Aged
  • Patient Satisfaction
  • Postoperative Complications
  • Prospective Studies
  • Radio Waves
  • Refraction, Ocular / physiology
  • Safety
  • Treatment Outcome
  • Visual Acuity / physiology