Abstract
Myopia is the most common refractive error throughout the world. Exact and relative etiologies of myopia have not been investigated in detail, although the high prevalence rate of myopia in school children has been well documented. Patients with myopia must endure the physical and financial burden of spectacles or contact lenses throughout their lives. The National Eye Institute estimated that the costs of refractive eye examinations amount to $1 billion annually, with another $1.5 billion spent on eyeglasses each year. The age of onset of myopia is frequently between 5 to 15 years. There has been a dramatic increase in the prevalence rates of myopia over the past decades in Korea and other parts of Asia. The prevalence rate was 8~15% in 1970s, 23% in 1980s, 38% in 1990s, and 46.2% in 2000s in Korean school children. The remarkable increase in Asian school children suggests that life style risk factors during the school periods may have a great impact on the development of school myopia and the overall population prevalence rate of myopia. Because the gene pool has not changed significantly over the past decades, the rapid increase of the prevalence rates of myopia has been attributed to increases in near-work activities and environmental factors. Atropine is effective in preventing myopia by a non-accommodative mechanism. Atropine is a broad-band muscarinic antagonist that binds to all five identified muscarinic receptors. Animal and clinical studies have shown that the M1-selective muscarinic antagonist, pirenzepine, is effective in reducing axial length enlargement and preventing myopia.
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