Tutton M K, Cherry P M
Corneal Laser Centre, Clatterbridge Hospital, Bromborough, Merseyside, United Kingdom.
Ophthalmic Surg Lasers. 1996 May;27(5 Suppl):S521-4.
Treatment of hyperopia is more of a challenge than PRK but the development of the holmium:YAG laser has provided a more controlled way of carrying out laser thermokeratoplasty (LTK).
Twenty two eyes with hyperopia were treated with a Summit Technology OmniMed holmium laser by placing two rings of eight laser spots at 6.5 and 9 mm (centred on the visual axis) to produce a 4.00 diopters (D) correction.
An average +2.10 D refractive correction was achieved in the 17 eyes with no induced astigmatism with an accuracy of 25% within 1.00 D, 60% within 2.00 D and 100% within 3.00 D. However, significant astigmatism (+1.25 to +2.5 Dcyl) was produced in 23% of eyes from 6 months post-laser and these required astigmatic LTK correction.
The overall results were disappointing in that there was an approximate 50% regression at two years post-LTK. However, the rate of regression was very slow at 24 months, and most patients remarked how well they could see in the first few months following the treatment.
远视的治疗比准分子激光原位角膜磨镶术（PRK）更具挑战性，但钬：钇铝石榴石激光的发展为进行激光热角膜成形术（LTK）提供了一种更可控的方法。
22只远视眼采用Summit Technology OmniMed钬激光治疗，在视轴中心6.5毫米和9毫米处放置两圈，每圈8个激光点，以产生4.00屈光度（D）的矫正。
17只眼平均获得+2.10 D的屈光矫正，无诱导散光，在1.00 D范围内的准确性为25%，在2.00 D范围内为60%，在3.00 D范围内为100%。然而，激光治疗后6个月，23%的眼睛产生了显著散光（+1.25至+2.5 Dcyl），这些眼睛需要进行散光LTK矫正。
总体结果令人失望，因为LTK术后两年有大约50%的回退。然而，24个月时回退速度非常缓慢，大多数患者表示治疗后的头几个月视力很好。
