Clinical Research Directory

Efficacy of Different Interventions for Progressive Myopia After Orthokeratology Lens Wear

Myopia has emerged as a significant concern impacting the visual health of children and adolescents on a global scale. According to research conducted by Holden BA et al., it is projected that by the year 2050, the worldwide prevalence of myopia and high myopia will experience a substantial increase, affecting approximately 5 billion and 1 billion individuals, respectively, with particularly high prevalence rates observed in East Asia\[1\]. The persistent rise in myopia incidence, coupled with the escalation of complications associated with high myopia, is anticipated to exert complex socio-economic repercussions \[2\]. Consequently, the prevention of myopia onset and the management of axial length elongation have become critically important \[3\]. Orthokeratology (Ortho-K) is a procedure that involves the overnight application of specially designed reverse geometry rigid gas permeable contact lenses to achieve temporary corneal reshaping and reduce myopia during the day\[4,5\]. In children with mild to moderate myopia, Ortho-K has demonstrated visual correction efficacy ranging from 80% to 92%\[6,7\]. Nonetheless, its efficacy in controlling myopia progression may not match its corrective efficacy. The therapeutic effect of Ortho-K in decelerating axial elongation is reported to range from 43% to 63%. Despite the use of Ortho-K, approximately 15% of children continue to exhibit rapid axial elongation exceeding 0.36 mm per year.\[8,9\]. In recent years, adjunctive interventions such as low-concentration atropine eye drops, modification of the back optical zone diameter (BOZD) of orthokeratology (Ortho-K) lenses, and low-level red-light therapy (RLRL) have been proposed to augment the myopia control efficacy of Ortho-K. Zhao et al. \[10\] reported that after one year of treatment with either atropine orthokeratology (AOK) or Ortho-K lenses in children aged 5-14 years, the axial length (AL) increased by 0.14 mm and 0.29 mm, respectively. Another study involving children aged 8-12 years \[11\] demonstrated that after one year of treatment, the AOK group exhibited a 17% reduction in AL growth (0.20 mm vs. 0.24 mm). Research conducted by Xiong et al. \[12\] indicated that for children whose eyes elongated by at least 0.50 mm within one year of Ortho-K wear, the combination of RLRL therapy with Ortho-K significantly reduced axial elongation compared to Ortho-K alone. Additional studies have suggested that decreasing the BOZD can enhance the extent and degree of mid-peripheral corneal steepening, thereby decelerating axial elongation \[13-15\]. Most existing studies primarily compare a single intervention against a control group, thereby lacking direct "head-to-head" comparisons. Traditional meta-analyses are limited to comparing two interventions at a time and often fail to assess multiple treatments concurrently. Consequently, most meta-analyses offer only statistical insights into the efficacy of individual interventions. Clinically, it is common to combine two or more interventions to treat myopia, particularly in cases of rapidly progressive myopia. Previous research has indicated that combined interventions may have additive effects in the prevention and control of myopia; however, these findings require further empirical validation. This study employs a retrospective approach to evaluate the efficacy of various treatment strategies in managing axial elongation in children aged 8-12 years who experience rapid axial progression following Ortho-K lens wear. The objective is to provide a scientific foundation for the development of personalized myopia control plans.

MAD Trial: Myopia Atropine Dose

The goal of this interventional study is to compare the efficacy of Atropine 0.05% to Atropine 0.5% treatment against progression of axial length in European children with progressive myopia, and to evaluate the safety, adherence, and reasons for nonresponse. Subjects will use Atropine eye drops for a period of 3 years, followed by a 2 year observational period.