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Background. Aniesekonia may limit the effectiveness of conventional optical correction in prevention/treatment of amblyopia. Co-existent medical conditions – esp developmental / cognitive may prevent / limit the use of conventional treatment techniques.
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Background • Aniesekonia may limit the effectiveness of conventional optical correction in prevention/treatment of amblyopia. • Co-existent medical conditions – esp developmental / cognitive may prevent / limit the use of conventional treatment techniques. • PRK and LASEK have been shown to be safe in children and present a useful alternative in the above situations.
Study Aims • To examine the long term visual outcomes in children after surgical refractive correction and evaluate differences in outcomes between those who had PRK and those who had LASEK.
Methods • Retrospective Case Series • Patients treated with PRK or LASEK based solely upon time of presentation (ie. Non randomized).
Methods • Inclusion Criteria • ‘end stage treatment failures in whom traditional methods of optical correction were not successful’ • Unable to wear glasses and / or contact lenses • And > 3.0D of anisometropic myopia • And / or more than -5.0D of bilateral myopia • ‘chosen as representing a point at which visual blurring and / or anisometropia, when not corrected would have substantial impact on the child’s ability to function in his or her environment’ • All patients were included regardless of co-morbid medical diagnoses. • Conventional treatments such as atropine and patching continued.
Methods • Refractive Methodologies • General anaesthesia • Camellin-Shahinian LASEK nomogram. • Myopia <8.0D : 10% reduction off spectacle plane sphere • -8.0D to -10.0D 15% off • >-10.0D 20% off.
Methods • Primary Outcome Measures: • Refractive Error • Corneal Clarity / Haze (graded 0 to +3) • BCVA • Other outcomes • Stereopsis (Titmus, Lang1, Frisby) • Macular / extramacular fusion (Worth 4 dot)
Results • 56 eyes of 39 children treated. • 27 eyes PRK, 29 eyes LASEK • Mean age 6.5 yrs (R 1.0 to 17.4 years) • Mean follow up 5.15 years (R 3.5-7.8 yrs)
Results • Refractive Error • Range treated was large (+1.75D to -27.0D) • At last follow up 77% within 3 dioptres of target SE. • ‘Although the SE remained relatively stable, by 2 years postoperatively, laser myopic regression was noted in some children. Twenty-four eyes (43%), 13 (54%) in the PRK group and 11 (46%) in the LASEK group, required a second laser procedure.’ • Secondary Procedure mean at 26 months. • Mean SE after second treatment -1.73D
Results • Refractive Error
Results • Corneal Clarity / Haze • Not significant in any child.
Results • BCVA • 28 of 39 children could have VA measured • 42.9% (12)had improved BCVA • Remainder unchanged • None were worse. • 5 of 28 had >5 lines improvement at 12 months.
Results • Stereopsis • Steropsis and fusion did seem to improve with treatment.
Comments • Small study – only 56 eyes. • Retrospective • Limited descriptive statistics only. • No measures of statistical significance. • Limited comparison between two modalities. • Non randomised. • No control or sham treatment group. • Single centre
Comments • Despite claims of relatively stable SE, almost a half of patients suffered myopic regression that required enhancement at around 2 years post initial treatment. • Seems relatively safe – whilst significant numbers suffered haze, no one was worse off
Comments • Did seem to be improvements in BCVA, SE and stereopsis/fusion. • Though conventional treatments such as patching etc. continued. • Need to be examined in setting of RCT to bear out these findings. • Longer term follow up also required – eg incidence of keratectasia, keratoconus