Myopic refractive error, also known as nearsightedness, is a common refractive error that causes visual impairment and can worsen over time.
When nearsighted, the patient’s eyeball will be longer than that of normal people, causing the image of the object to be focused first instead of on the retina, making the patient see clearly only near objects and have difficulty observing objects. far. Long-term nearsightedness can change the eye structure, leading to the risk of other eye diseases such as amblyopia, retinal degeneration, ….
Currently, to correct myopia refractive error, there are many methods that have been used such as wearing glasses, contact lenses or surgery. However, the above methods all have major disadvantages, myopia is too entangled when active, surgery is expensive and must be 18 years old, etc., so a new method was born. are night contact lenses (ortho-k glasses).
Night contact lenses
Ortho-K contact lenses.
Advantages
- Slow down the development of refractive errors: myopia, astigmatism.
- Only affects the eyes temporarily, does not interfere, invasive, affect the eyes, minimize risks.
- Can easily change to using glasses or surgery when needed
Defect
- Must sleep for 6-8 hours for the glasses to maximize their use, a bit sticky in the eyes, not suitable for people who have difficulty sleeping, have pathologies on the corneal surface (dry eyes, …)
- Only can correct myopia lower than -6 diopters, farsightedness has not been treated