Myopia: Attempts to arrest progression

Tan Tock Seng Hospital, Tumasik, 00, Singapore
British Journal of Ophthalmology (Impact Factor: 2.98). 12/2002; 86(11):1306-11. DOI: 10.1136/bjo.86.11.1306
Source: PubMed


Previous studies have evaluated the efficacy of several interventions to decrease the progression of myopia. These include devices that alter the perception of the visual environment and pharmacological treatments. There is no conclusive evidence thus far that alteration of the pattern of spectacle wear, bifocals, ocular hypotensives, or contact lenses retards the progression of myopia. Several randomised clinical trials have demonstrated that the rate of progression of myopia is lower in children given atropine eye drops than those given placebo. However, atropine is associated with short term side effects such as photophobia and possible long term adverse events including light induced retinal damage and cataract formation. Other more selective antimuscarinic agents such as pirenzipine are presently being evaluated. Further well conducted randomised clinical trials with large sample sizes and adequate follow up designed to evaluate treatments to retard the progression of myopia should be conducted, since the identification of an effective intervention may have a greater public health impact on the burden and morbidity from myopia than the few treatments currently available.

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    • "Thus, myopia is suggested to be a multi-faceted phenomenon, and variety of attempts for its treatment were made throughout the world, including medical therapies [14], lens and eye exercises [15,16], and massage therapies [17]. Unfortunately, these attempts did not achieve cure or became the base for standard treatment. "
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    ABSTRACT: To evaluate the efficacy of two non-surgical interventions of vision improvement in children. A prospective, randomized, pilot study to compare fogging method and the use of head mounted 3D display. Subjects were children, between 5 to 15 years old, with normal best corrected visual acuity (BCVA) and up to -3D myopia. Subjects played a video game as near point work, and received one of the two methods of treatments. Measurements of uncorrected far visual acuity (UCVA), refraction with autorefractometer, and subjective accommodative amplitude were taken 3 times, at the baseline, after the near work, and after the treatment. Both methods applied after near work, improved UCVA. Head mounted 3D display group showed significant improvement in UCVA and resulted in better UCVA than baseline. Fogging group showed improvement in subjective accommodative amplitude. While 3D display group did not show change in the refraction, fogging group's myopic refraction showed significant increase indicating the eyes showed myopic change of eyes after near work and treatment. Despite our lack of clear knowledge in the mechanisms, both methods improved UCVA after the treatments. The improvement in UCVA was not correlated to measured refraction values. UCVA after near work can be improved by repeating near and distant accommodation by fogging and 3D image viewing, although at the different degrees. Further investigation on mechanisms of improvements and their clinical significance are warranted.
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    • "In myopic children, muscarinic antagonists such as atropine and pirenzepine have been used therapeutically to slow the progression of disease (Saw et al., 2002; Tan et al., 2005; Chua et al., 2006; Siatkowski et al., 2008; Gwiazda, 2009; Tong et al., 2009; Ganesan and Wildsoet, 2010). Atropine, a non-subtype-selective muscarinicreceptor blocker has been shown to be effective at a concentration of 0.025% (Fang et al., 2010), as compared with pirenzepine, which shows a limited degree of selectivity for blocking only M 1 receptors at 2% concentration (Siatkowski et al., 2008). "
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    ABSTRACT: Myopia is a huge public health problem worldwide reaching the highest incidence in Asia. Identification of susceptible genes is critical for understanding the biological basis of myopia. In this paper, we have identified and characterized a functional myopia-associated gene using a specific mouse-knock out model. Mice lacking muscarinic cholinergic receptor gene (M2) were less susceptible to lens-induced myopia compared to wild type mice, which showed significantly increased axial length and vitreous chamber depth when undergoing experimental induction of myopia. The key findings of this present study is that M2 mutant mice sclera has high expression of collagen type I and low level of collagen type V than WT and other muscarinic sub types mutant mice, and therefore M2 mutant mice were resistant to develop experimental myopia. Pharmacological blockade of M2 muscarinic receptor proteins retarded myopia progression in the mouse. These results suggest for the first time a role of M2 in growth related changes in extra cellular matrix genes during myopia development in a mammalian model. M2 receptor antagonists may thus provide a targeted therapeutic approach to the management of this refractive error.
    Full-text · Article · May 2013 · Disease Models and Mechanisms
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    • "A recent study using the human scleral tissue showed that atropine increased FGF2 activation in a dose-dependent manner [33], while the authors also reported atropine reduced cell proliferation of scleral fibroblasts. Since atropine has been demonstrated to retard myopia progression in humans [34,35], their FGF2 expression pattern is unexpected and hard to explain (personal communication with the correspondent author of the study [33]). Similar to our finding, FGF2 was significantly upregulated in the choroid/RPE of minus lens-treated eyes (i.e., eyes of induced myopia) of primate marmoset monkeys as compared with plus lens-treated fellow eyes (i.e., eyes of induced hyperopia) [36]. "
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