Two-Year follow-up of noncontact holmium laser thermokeratoplasty for the correction of low hyperopia

• Published in: Canadian journal of ophthalmology 2003-08, Vol.38 (5), p.385-392
• Main Authors: Rocha, Guillermo, Castillo, Juan Miguel, Sánchez-Thorin, Juan Camilo, Johnston, Jennifer, Cartagena, Rosario G.
• Format: Article
• Language: English
• Subjects: Adult; Biological and medical sciences; Corneal Topography; Corneal Transplantation - adverse effects; Eyeglasses; Female; Follow-Up Studies; holmium laser thermokeratoplasty; holmium:YAG laser; Humans; hyperopia; Hyperopia - pathology; Hyperopia - physiopathology; Hyperopia - rehabilitation; Hyperopia - surgery; Hyperthermia, Induced - adverse effects; Intraoperative Complications; keratomileusis; Laser Therapy - adverse effects; Male; Medical sciences; Middle Aged; Ophthalmology; Prospective Studies; Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases; Surgery of the eye and orbit; Vision disorders; Visual Acuity
• ISSN: 0008-4182; 1715-3360
• DOI: 10.1016/S0008-4182(03)80050-9

Purpose: To summarize the 2-year results of laser thermal keratoplasty with a holmium:yttrium-aluminumgarnet (Ho:YAG) laser and the Sunrise Corneal Shaping System and assess the procedure's safety, efficacy and predictability in correcting hyperopia in a phase III clinical intervention case series. Methods: The Ho:YAG laser was used to correct low hyperopia (manifest spherical equivalent of +0.75 to +2.50 dioptres [D], with manifest cylinder of 1.00 D or less) in 38 eyes of 28 patients 40 years of age or older. Laser pulses were delivered to the cornea in 2 radially placed, concentric, 8-spot rings 6.0 and 7.0 mm in diameter. The last follow-up was at 2 years. Results: The preoperative uncorrected visual acuity (UCVA) at distance was less than 20/40 in 82% of the eyes and at near was less than 20/32 in 42%. At 2 years the distance UCVA was 20/40 or better in 100% of the eyes and 20/20 or better in 84%, and the near UCVA was 20/32 or better in 97% of the eyes and 20/20 or better in 8%. The difference between the preoperative and postoperative UCVA was statistically significant (p < 0.01). The correction at 2 years was within 0.50 D of that intended in 92% of the eyes and within 1.00 D in 100%. The reduction in mean spherical equivalent at 2 years was statistically significant (p < 0.0001). No loss of 2 lines or more in best-corrected visual acuity occurred after the I st month of follow-up. Interpretation: The Ho:YAG Sunrise Corneal Shaping System is safe and effective for the treatment of low hyperopia and astigmatism. It provides a predictable refractive outcome at 2 years of follow-up. However, our results show a tendency towards regression by 2 years. Objet : Résumé de 2 années de kératoplastie thermique au laser avec le laser holmium:yttrium-aluminum-garnet (Ho:YAG) et la technique de modification de la courbure de la cornée Sunrise et évaluation de la sécurité, de l'efficacité et de la prédictibilité du procédé de correction de l'hypermétropie dans une série de cas d'intervention clinique de phase III. Méthodes : L'on a utilisé le laser Ho:YAG pour corriger l'hypermétropie faible (équivalence sphérique manifeste de +0,75 à +2,50 dioptries [D], avec expression cylindrique de 1,00 D ou moins) chez 38 yeux de 28 patients de 40 ans ou plus. Les impulsions laser ont été appliquées à la cornée en 2 faisceaux de 8 points concentriques et de 6,0 et 7,0 mm de diamètre. Le dernier suivi remontait à 2 ans. Résultats : Avant l'opération, l'acuité visuelle non cor