From the Research
Myopia, or nearsightedness, occurs when the eye grows too long from front to back or when the cornea is too curved, causing light rays to focus in front of the retina rather than directly on it, and this condition is influenced by both genetic and environmental factors, as supported by recent studies 1, 2. The pathophysiology of myopia is complex and involves the interplay of multiple factors.
- Genetically, multiple genes affect eye development and growth, with children of myopic parents having a higher risk, as noted in studies 3, 4.
- Environmentally, insufficient outdoor time and excessive near work, such as reading or screen use, contribute to myopia development by altering the eye's growth signals, as discussed in 1, 5. When focusing on near objects, the ciliary muscle contracts to change lens shape, and prolonged near focus may trigger biochemical signals that promote eye elongation.
- Additionally, peripheral retinal defocus, where peripheral light focuses behind the retina while central vision remains clear, may stimulate compensatory eye growth, as explained in 2, 5. This complex interplay of factors leads to the refractive error where distant objects appear blurry while near objects remain clear, as the elongated eye cannot properly focus light on the retina for distant vision. The most recent and highest quality study 2 suggests that orthokeratology combined with atropine is more effective in reducing the progression of myopia and axial elongation, highlighting the importance of considering both genetic and environmental factors in the management of myopia. Key factors to consider in the pathophysiology of myopia include:
- Genetic predisposition
- Environmental influences, such as near work and outdoor activity
- The role of peripheral retinal defocus in stimulating eye growth
- The potential benefits of combined treatments, such as orthokeratology and atropine, in slowing myopia progression, as supported by 5.