With primary and secondary schools now entering winter break, many parents are taking advantage of the holiday to bring their children for vision checkups—prescribing glasses where needed and initiating treatments. Simultaneously, the extended time spent indoors during the break marks a peak period for the battle against electronic devices to protect children's vision.How can myopia be effectively prevented? What pitfalls should be avoided in myopia prevention and treatment? Do those long-promoted "eye protection gadgets" actually work? Our reporter consulted multiple ophthalmology experts to provide answers for parents.
Should myopia prevention wait until school starts? Are OK lenses truly effective?
Q: Should myopia prevention wait until children start school?
Professor Yang Xiao, Department of Refractive and Low Vision, Zhongshan Ophthalmic Center, Sun Yat-sen University: To delay the onset of myopia in adolescents, slow its progression, and reduce its incidence rate, the "defense line" should be moved forward to the preschool stage. During elementary school, it should be "strictly guarded, fighting for every inch."During middle school, especially junior high, leverage peer education to instill the concept of "utilizing spare moments for scientifically sound eye care."
Ages 5 to 7 are critical for developing healthy eye habits. During the transition from preschool to elementary school and in early grades, parents often focus on cultivating good study habits. In reality, as reading and writing time increases, children in this age group equally need to prioritize proper eye care. Poor posture and prolonged close-up work are triggering factors for myopia, while over an hour of daily outdoor activity can effectively prevent it.
Myopia progresses most rapidly around school age, so preschoolers should minimize close-up reading and engage in more outdoor activities.
Q: Do OK lenses actually work? Can they correct pseudomyopia?
Yang Xiao: Orthokeratology (OK lenses) are specially designed corneal contact lenses made from highly oxygen-permeable materials.Worn overnight, they ensure clear daytime vision. By reshaping the cornea's front surface, they reduce myopia and astigmatism.
Orthokeratology is a non-surgical, reversible corrective method. "Reversible" means vision gradually returns to pre-correction levels after discontinuing use. Consistent, proper wear is essential to maintain optimal vision.Orthokeratology lenses are suitable for adolescents aged 8 and above and adults with myopia below 500 degrees or regular astigmatism below 150 degrees. Patients must undergo relevant examinations at a hospital and meet all criteria before wearing them.
Research indicates that orthokeratology lenses can effectively slow myopia progression by reducing the rate of axial length elongation in myopic eyes, making it one of the current effective methods for controlling myopia development.
As orthokeratology lenses come into direct contact with the eye, strict adherence to hygiene practices is essential. Individual conditions and visual habits vary, so outcomes may differ even among users of the same lenses.
If diagnosed with pseudomyopia, OK lenses are not recommended at this stage. However, proactive myopia prevention is essential. Pseudomyopia can serve as an early warning sign. Upon detection, immediate preventive measures should be taken, such as increasing daytime outdoor activities and maintaining proper eye posture.
(Guangzhou Daily Full Media Reporter Ren Shanshan, Correspondent Tai Mengyun)
Are blue light blocking glasses effective for children's eye protection?
Q: Do blue light blocking glasses help protect children's vision when using smartphones, tablets, and other electronic devices?
Professor Li Zhenping, Associate Chief Physician at Guangdong Provincial Hospital of Ophthalmology: Prolonged exposure to electronic devices like computers and phones involves blue light of specific wavelengths that can damage the retina and lens. Some blue light blocking glasses on the market filter or reduce these wavelengths, effectively mitigating harm to the macula and retina. For adults, wearing such glasses while using computers or phones is recommended.However, they are not recommended for children in the visual development stage. Light consists of various wavelengths, and each wavelength plays a role in stimulating visual development during critical periods. Intentionally blocking one or more wavelengths can disrupt normal visual function development, potentially leading to defects in fusion or stereoscopic vision. Therefore, children under 12 years old who are still in the developmental stage should not wear blue light blocking glasses.
Q: Can eating more pig liver and goji berries reduce myopia?
Li Zhenping: Traditional folk wisdom has long held that pig liver and goji berries are beneficial for eye health, especially for children. Modern medical research indicates this belief has some theoretical basis.
Studies show that calcium, zinc, vitamin B, and vitamin A are common nutrients essential for children's eye development.Zinc plays a crucial role in maintaining optic nerve development during the formation of the retinal choroid, supporting the function of photoreceptor cells. Zinc is abundant in our daily diet, with the most common sources being seafood like sea fish, laver, and kelp. Among land-based foods, animal liver is particularly rich in zinc.In this sense, appropriate liver supplementation can indeed boost zinc intake, benefiting eye development—thus supporting the claim that pork liver improves vision. Goji berries, regarded in traditional Chinese medicine as beneficial for essence, kidney health, and vision, are also eye-friendly from a modern medical perspective. Rich in carotene, vitamins A and B, calcium, iron, and other nutrients essential for eye health, they support ocular development.
However, simply consuming pork liver and goji berries does not guarantee improved vision or reduced myopia. True myopia cannot be reversed; it can only be controlled and its progression slowed. Traditional Chinese medicine advocates treating illness before it manifests, while modern medicine emphasizes early prevention and intervention—the same principle applies to myopia.For children preventing myopia, dietary balance remains paramount. Moderate intake of foods rich in calcium, zinc, vitamins A and B, and carotenoids is advisable, while reducing consumption of sweets is recommended.
(Guangzhou Daily Full Media Reporter Zhou Jieying, Correspondent Song Liping)
Why do children develop myopia despite minimal electronic device use?
Q: Why do children experience myopia even with almost no electronic device usage?
Professor Sha Xiangyin, Director of Ophthalmology at Guangzhou Medical University Second Affiliated Hospital: First, myopia has multiple causes, including genetics, ethnicity, environment, diet, and visual habits. Therefore, avoiding electronic devices does not guarantee immunity from myopia.Additionally, students today face increasingly heavy academic burdens. Prolonged study sessions combined with poor posture—or even reading while lying down—place excessive strain on the eyes, contributing to the onset and progression of myopia. Some children are also picky eaters and lack outdoor exercise, which are equally significant factors in myopia development.
Q: At what age can children undergo myopia correction surgery? Which is better: SMILE or LASIK?
Sha Xiangyin: Refractive surgery is generally recommended for individuals aged 18 and above. This is because stable myopia progression is a prerequisite for surgery. If the patient is younger and their eyeball is still growing, myopia may continue to worsen annually, making surgery inadvisable under such circumstances.
Full-flying second and half-flying second procedures suit different levels of myopia.All-femtosecond laser surgery is less invasive than SMILE and has a lower rate of postoperative complications. However, it imposes stricter requirements on the patient's eye conditions and myopia degree. Patients with very high myopia or insufficient corneal thickness are not suitable for all-femtosecond laser surgery and are better suited for SMILE. Overall, if eye conditions permit, all-femtosecond laser surgery should be considered first. If it is not suitable, then SMILE should be considered.