Holmium:YAG laser thermokeratoplasty for correction of astigmatism.

The effect of astigmatic Holmium:YAG laser thermokeratoplasty in three eyes with previous surgery (extracapsular cataract extraction, penetrating keratoplasty and failed extracapsular cataract extractionntric photorefractive keratectomy 1 to 7 years previously) was evaluated. In the extracapsular cataract extraction eye the effect of a four-spot laser thermokeratoplasty regressed to almost zero within 1 week. In the penetrating keratoplasty and photorefractive keratectomy eyes an eight-spot laser thermokeratoplasty produced an enormous overshoot in astigmatic power of about 15.00 diopters (D), decreasing within 5 months to almost zero in the eye with penetrating keratoplasty and to 4.00 to 5.00 D corneal astigmatic power in the photorefractive keratectomy eye after 8 months of observation.