Myopia

What Should Parents Pay Attention to When Controlling Children's Myopia? Smart Eye Care Tips You Need to Know

Children today frequently use computers for online classes. Even when not attending lessons, they remain glued to their phones and tablets, rarely putting down their devices. Consequently, many children develop myopia at an early age.A survey revealed that over half of myopic children aged 4 to 12 who participated in e-learning during the pandemic experienced worsening myopia. This significantly increases the risk of developing high myopia, potentially leading to more severe eye health issues in the future. Therefore, as parents, it is crucial to teach children early on how to protect their eyes and implement effective myopia control to prevent worsening myopia. Here are nine tips to share with you. When using smartphones, computers, browsing the internet, or reading, remember to pay attention to the following points:

Every 20 minutes, give your eyes a break.

Ensure adequate lighting when reading.

Maintain a minimum viewing distance of 30 centimeters.

Adjust the screen brightness to a comfortable level.

Do not watch while lying in bed or riding in a vehicle.

Increase the amount of time spent on daily outdoor exercise

Go to bed early and rise early every day.

多進食含豐富維生素A的食物
例如紅蘿蔔

Get comprehensive eye exams early and regularly.

白內障初期無法從外觀判斷，須經過眼科細隙燈儀器檢查才能確定。在初期，水晶體會由透明狀，逐漸變黃，甚至產生深咖色，也就是俗稱的「變熟」。白內障的形成是水晶體的蛋白質因變異而導致混濁，混濁後就不可回復，所以目前無法靠吃藥或點藥水使白內障回復。

因此，進行白內障手術搭配人工晶體置換是目前臨床上唯一有效的治療方式。

白內障症狀

白內障最常見的症狀是視力逐漸模糊，一般而言，早期的白內障的症狀並并不明顯，當病情逐漸加重時，患者便會發現：

• 視力模糊，原本清晰的影像變得朦朧：白內障所導致的視力模糊會讓患者難以看清眼前事物，尤其在較暗的環境下，老人家可能會因爲看不清而容易跌倒。
• 眩光：在太陽光或較强的光線下，患者可能會感覺有眩光或閃光，大大影響在明亮環境中的視覺舒適度。
• 雙影：白內障可能導致看東西有重影，使得物體看起來彷彿有重疊或分離的感覺，在這種情況下老人家可能會在行走時失去平衡，增加摔倒的風險。
• 近視度數加深而以為老花眼減輕：有老花眼的患者可能會注意到他們看近物時變得清晰，會誤以為是老花眼的症狀減輕，實際上這可能是白內障引起的視力變化。

白內障的初期症狀可能並不會影響日常生活，但隨著時間推移，水晶體混濁的部分可能會隨之擴散，導致更明顯的白內障症狀，甚至失明。

如果您有白內障症狀或發現視力有任何變化，請立即向我們的眼科醫生約診。

白內障自我檢查

儘管白內障自我檢查無法替代專業眼科檢查，但有些簡單的觀察和注意事項可以讓你察覺是否存在潛在的白內障症狀。如果您發現已有白內障先兆，應及早諮詢眼科專業醫生的建議。

以下是一些白內障自我檢查的指南：

1. 是否感覺遠近事物總是模糊不清？
2. 是否感覺老花眼突然改善？
3. 是否會怕光？
4. 是否會感覺事物有重影、眩光/光暈？
5. 是否會感覺看東西顔色偏黃/不鮮艷？
6. 是否發現近視度數不斷加深？

若符合以上其中數項，亦有可能是罹裏患白內障的先兆，請儘早與我們的眼科醫師預約，進行專業的檢查和診斷，及早發現和治療白內障有助於維護良好的視力和生活品質。

最常見的白內障成因

白內障主要成因是水晶體老化，是老人家常見的眼疾，但亦有可能由其他原因引起。以下是一些其他常見的白內障成因：

Diabetes

白內障被認爲是糖尿病患者視力問題的主要成因。這是因為糖尿病患血液中的糖分較高，高血糖會使水晶體腫脹及混濁，最終形成白內障。

外傷

眼睛受到外傷或創傷也可能成爲白內障的成因之一。這可能包括眼部手術、事故或其他傷害。

發炎

眼部組織的發炎可能導致白內障的發展。這可能是由於眼睛感染、眼部疾病或其他炎症性疾病引起的。

遺傳

家族遺傳也有可能是白內障的成因之一。如果家族中有人患有白內障，其他成員可能也更容易患上白內障。

長期服用類固醇

長期使用類固醇或在高劑量下使用類固醇都會增加罹患白內障的風險。這是因為類固醇可能會使水晶體變質，影響水晶體的透明度和正常功能。

高度近視

高度近視者（200~300度）是白內障的高風險群體。這是因爲高度近視者的眼內結構已發生變化，這可能會增加水晶體的負擔，進而導致水晶體加速老化，最終促使白內障的形成。

了解這些白內障的成因有助於更好地預防及發現白內障的早期症狀，以獲得最佳治療時期。如果有白內障的病徵或風險因素，應及早向眼科醫師諮詢。

白內障種類

雖然白內障的最終治療方案都是微創手術，但眼科醫生都會在術前分析及瞭解患者罹患白內障的成因及症狀來判斷患者屬於哪一類型的白內障，避免錯過最佳治療黃金期。臨床上，我們大致將白內障分成6類：

核心型白內障

核心型白內障是最常見的白內障類型，常發生在40歲左右的人身上，不過高度近視者有可能會更早發生。核心型白內障即水晶體從中間開始「[熟」]，由於這類白內障發展較緩慢，大部分人在初期時不會有視力問題，甚至有些原有老花的人會覺得自己的老花眼有所改善。然而，隨著白內障逐漸成熟，視力便會快速下降，而且看到的顔色也會因爲光線進入的角度關係而導致辨別顔色能力減弱。

皮質型白內障

皮質型白內障發生在外圍皮質層，這種類型的白內障更好發於糖尿病患者。皮質型白內障的成因是由於水晶體皮質的變質造成混濁，導致水晶體周邊模糊，看不清楚。這類白內障在初期時症狀較不明顯，但它會漸漸向核心部位蔓延，就會開始產生視力模糊問題。

後囊型白內障

後囊型白內障由許多小斑點形成，主要發生在水晶體後囊膜的中央，與後囊膜老化或上皮細胞生長過度有關。這些小斑點會遮擋光線，使光線無法完整的到達視網膜，導致患者在强光下看事物時變得模糊、顔色不鮮艷；在夜間時則會看見眩光、光暈等問題。這類白內障通常比其它類型的白內障發展更快，尤其常發生在長期或大量服用類固醇的病患身上。

先天型白內障

先天型白內障是指在出生時就存在的白內障。這可能是由於遺傳因素、母體感染或其他胎兒發育問題所引起的。

續發型白內障

續發型白內障是由其他眼部問題或全身性疾病引起的。例如糖尿病、眼部炎症或使用某些含有類固醇藥物都可能導致續發型白內障。

創傷型白內障

創傷型白內障是由眼部創傷而引起，包括眼球受傷、手術後併并發症或其他意外事故。這些創傷可能導致水晶體混濁，進而影響視覺。

若感到視力異常或發現有白內障的病徵，建議及早就診查明病因，以免延誤診治。

過熟做白內障手術後遺症

一旦發生白內障，什麼時候要接受手術？在還沒有超音波晶體乳化術的年代，白內障手術傷口大，縫合時間以及恢復期較長，因此都是等到水晶體很熟很硬才開刀。目前因為「超音波晶體乳化術」的普及，白內障手術的成功率非常高，傷口很小，恢復快。

此外，因為一旦白內障過熟時，還可能併發青光眼、虹彩炎，嚴重可能失明，也增加手術的困難度。因此，手術最佳時機是只要發現白內障症狀明顯或視力已影響日常生活，就建議動手術更換水晶體。但若拖到此時才動手術，時機已經太晚。

了解更多白內障術後應該如何保養？

Presbyopia is a natural aging phenomenon associated with age that causes a loss of the ability to see nearby objects clearly. Presbyopia occurs in everyone's life. Even individuals who have enjoyed perfect vision throughout their lives will eventually begin to experience difficulty focusing on close objects, particularly when performing tasks such as threading a needle.

There is currently no cure for presbyopia. However, several treatment options can correct your vision. Depending on your condition and lifestyle, you may choose corrective eyeglasses, contact lenses, laser vision correction, or surgery to improve your vision.

Select and wear appropriate reading glasses.

Progressive lenses are designed with the upper portion for distance vision and the lower portion for near tasks. However, they lack visible lines and provide a smoother transition between the distance and near prescriptions. Since the needs for presbyopic and hyperopic aging differ, we do not recommend purchasing reading glasses on your own.

Laser Blended Vision (LBV) Presbyopia Laser Vision Correction

This technology compensates for the limitations of monovision, creating a "Blend Zone" for patients to achieve excellent near, intermediate, and distance vision without compromising existing color sensitivity or depth perception.

Cataract Surgery

If an elderly person has cataracts, they may choose to correct one eye (the dominant eye) to 0 diopters for clear distance vision, while correcting the other eye (the non-dominant eye) to 50 to 150 diopters of myopia (monovision correction). However, this approach is not suitable for everyone.Some individuals find it impossible to adapt. Ophthalmologists typically recommend testing monovision correction with contact lenses before proceeding with surgery. Alternatively, multifocal intraocular lenses can be implanted to adjust the degree of presbyopia. However, doctors must discuss potential side effects with patients, such as halos, glare, and reduced contrast sensitivity.

高度近視是相對嚴重的近視水平。600度或以上的近視，醫學上定義為高度近視。它的形成和眼球長度改變有關。成年人眼球的正常長度範圍是22-27mm。若長度大於27mm，便會造成高度近視。在幾乎所有情況下，遺傳都在高度近視的發展息息相關。如果父母雙方都近視，那麼他們的孩子也有更大的機會患高度近視。  高度近視本身通常不會導致視力下降。但是，患有這種疾病的人更有可能患上其他幾種威脅視力的疾病，包括：  

• 視網膜脫離 
• Glaucoma 
• Cataract 
• 視網膜穿孔甚至脫落
• 黃斑點病變及出血

即使激光矯視手術減輕高度近視度數，也無法避免併發症

近年有部分高度近視患者接受了激光矯視手術，近視度數減退了，於是也就忘了繼續關注原先的高度近視可能引起的問題。但事實上，激光矯視只是改變了角膜的弧度，並沒有改變眼球的長度。因此，所有因眼球過長而衍生的併發症，並不會因激光矯視而減少！

高度近視使白內障加深快

在最近對高度近視進行白內障和白內障手術結局的研究中，研究人員發現，與正常眼相比，高度近視眼的白內障發生得更快。此外，高度近視的眼睛並存疾病和並發症（如視網膜脫離）的患病率更高。

因此，高度近視的人必須進行常規的眼科檢查，以便他們的眼科醫生可以監控其眼睛的健康狀況，並尋找這些症狀以及嚴重近視的其他並發症的跡象。

近視不戴眼鏡會加深嗎?

一直有誤解，父母建議孩子延遲開始配戴眼鏡，儘量減少戴眼鏡的時間，或佩戴度數較淺的眼鏡能夠避免近視度數加深。

湯醫生指出：事實剛好相反，一副合適度數的眼鏡，可幫助輕鬆識別遠離的事物。

反之，使用不合適的鏡片處方會導致弱視，可能會惡化你的近視。

如果您在使用眼鏡時遇到頭痛或眼睛疲勞，可能意味著您的眼鏡度數太高或太低。

當然也有許多人質疑：「我幾乎都帶着眼鏡，但度數確實不斷加深？」

如果發生這種情況，那可能的原因是小朋友的眼球不斷發育，拉長，度數自然增加。

再者，如果用眼習慣不良及長時間盯着螢幕，都會誘發近視。

因此使用手機或平板電腦閱讀時，謹記在光源充足下進行，把電子產品的光度調低，字體大小、行距調至適中，減少眼睛疲勞；

如何不令近視加深?

湯醫生建議您：每閱讀 20 分鐘，遠看 20 呎遠的東西，休息 20 秒，讓睫狀肌有足夠的休息及放鬆。

沒有證據表明，按摩眼睛周圍區域等運動，可否幫助於延緩兒童近視加深。

反而過多按眼睛周圍的肌肉，會引致眼壓上升。

此外，高度近視的人若是快速轉動眼球，還有視網膜脫離風險。

父母誤解激光矯視手術可逆轉近視。

事實上，近視度數增加意味著眼球變長，這是沒有辦法讓眼球縮回到孩子視力完好時的長度。

激光矯視改變角膜的弧度，讓光線在沒有眼鏡或隱形眼鏡的幫助下聚焦到視網膜上。

眼球仍然可以繼續增長。

所以父母最好還是讓他們參加戶外活動。

澳洲有研究發現，孩子每周戶外活動達 14 小時，有助促使多巴胺的分泌，減慢近視的形成。

You may also be interested in:

假近視是什麼？假近視眼藥水可以分辨真假近視? — 有時並非真的近視，而是用眼過度後突然發生

高度近視威脅視力, 白內障症狀不可忽視 — 高度近視本身通常不會導致視力下降。但是，患有這種疾病的人更有可能患上其他幾種威脅視力的疾病

#近視不戴眼鏡後果 #近視不戴眼鏡會怎樣 #近視 不戴眼鏡 #近視沒戴眼鏡

Myopia Prevalence Among Children in Hong Kong

The prevalence of myopia among Hong Kong schoolchildren increases with age, doubling from 6.3% among preschoolers to 18.3% at age 6, and climbing to 61.5% by age 12. Among adults aged 21–30, the rate of myopia reaches as high as 84.7%.

If it progresses to high myopia, the risk of developing various eye diseases later in life—such as retinal detachment, cataracts, glaucoma, and macular degeneration—will increase significantly.

The goal of orthokeratology for children is not to completely halt the progression of myopia, but to slow down the rate of myopia progression.

Prevention of Myopia

If a child's myopia progresses by 100 degrees per year, this is considered rapid progression, and treatment may be considered. For children, the ideal progression rate is within 50 degrees per year.

Low-dose atropine eye drops have become a commonly used first-line treatment among ophthalmologists in recent years to slow the progression of myopia in children.

Research from the Chinese University of Hong Kong indicates that this method can effectively slow the progression of myopia in children by up to 60%, with rare side effects.

Additionally, a pair of "Multi-Zone Positive Optical Defocus" (DIMS) lenses designed by The Hong Kong Polytechnic University has been proven to slow the progression of myopia by up to 60% in participating children.

The lens comprises a "central optical zone" designed to correct refractive errors, along with a "multi-zone progressive myopic defocus" extending from the central zone to the periphery of the lens.

When the wearer views objects at different distances, DIMS lenses provide clear vision and myopic defocus to correct vision and help slow the progression of myopia.

Finally, children may choose to wear orthokeratology lenses (OK lenses).

It utilizes specially designed rigid orthokeratology contact lenses and the surface tension of tears to alter the curvature and shape of the cornea.

Children undergoing orthokeratology simply need to wear the reshaping lenses while sleeping at night, with the benefit of not needing glasses in the morning.

The only concern is that children may unconsciously rub their eyes during sleep, potentially causing corneal damage or infection. Therefore, this method is only suitable for children aged 8 and above who possess a higher level of self-care ability.

What is pseudomyopia?

Once a child develops myopia, parents become extremely anxious and often ask, "Does a child being diagnosed with a prescription mean they have true myopia?"

We know that the eye's ability to focus on distant and near objects is primarily due to the adjustment of the ciliary muscle and the lens, which allows images to be focused onto the retina, enabling us to see objects clearly.

We should be aware that the primary symptom of myopia is blurred vision when looking at distant objects.

However, if this situation occurs suddenly after excessive eye strain, don't rush to get new glasses right away, as you may be experiencing pseudomyopia.

Prolonged close-up viewing causes excessive contraction of the ciliary muscles. When shifting focus to distant objects, the muscles cannot relax immediately, causing the focal point to shift and resulting in blurred vision.

Pseudomyopia commonly occurs in schoolchildren because children's ciliary muscles possess stronger accommodative capabilities.

Additionally, the most prominent feature is fluctuating vision, particularly when shifting focus from near objects to distant ones, which then appear blurred.

Furthermore, myopia is less likely to be accompanied by astigmatism.

Fake Myopia Eye Drops to Distinguish Between True and False Myopia

If pseudomyopia is treated as true myopia and corrective lenses are prescribed, the patient's eyes will experience significant discomfort because the factors causing the ciliary muscle to contract and adjust have not been alleviated.

Finally, the doctor will use cycloplegic eye drops to dilate the pupils and relax the ciliary muscles, thereby distinguishing between true and false myopia.

How to improve pseudomyopia?

However, parents need not be overly concerned, as this situation is temporary.

With timely diagnosis and treatment, coupled with eliminating factors contributing to pseudomyopia—such as paying attention to reading distance, writing posture, and duration, frequently looking into the distance to allow the ciliary muscles to relax and adjust—the increased myopia can still be reversed.

It is worth noting that today's students are constantly glued to their tablets and smartphones, causing the ciliary muscles to remain in a state of prolonged tension. This can even lead to premature degeneration and weakness, rendering them unable to contract and adjust focus—thus turning "fake into real."

Therefore, if you notice any vision problems in your children, you should take them for an eye examination as soon as possible.

As parents, we naturally worry about our children's eye health.

Five Key Methods for Eye Protection

Statistics show that newborns have approximately 250 degrees of hyperopia, and they can only perceive black-and-white images before reaching six months of age.

Therefore, it is best to place high-contrast black-and-white patterns to help stimulate your baby's visual development.

Additionally, soft natural light is crucial for supporting the visual development of infants and young children.

It is recommended to keep curtains open during the day to expose your baby to light stimulation, but remember to avoid direct exposure of bright light to the infant's eyes.

Since infants under one year old are still developing their vision and their pupils do not constrict quickly, overly bright light can harm their eyes. Therefore, please turn off the flash when taking photos.

After infants reach six months of age, parents can hold brightly colored patterns about 12 inches (30 cm) in front of the child's eyes and gently wave them back and forth.

This helps develop eye coordination and train focusing ability in young children.

Vision screening can be done at home in Hong Kong

If you suspect your baby has poor vision, you may want to try some simple self-tests at home.

First, an infant's gaze typically follows light sources. Additionally, parents can cover one of the infant's eyes with a clean gauze cloth and observe whether the infant's waking behavior exhibits any abnormalities.

If an infant uses their weaker eye to see objects and experiences blurred vision that differs from their usual state, they may become anxious and restless, crying incessantly. In such cases, further examination should be conducted promptly.

Causes of Myopia

Additionally, any form of close-up work can induce myopia.

Prolonged close-up focusing work places increased strain on the ciliary muscles, causing the eyeball to elongate.

The American Academy of Pediatrics has issued guidelines advising against screen time for children under two years of age. For children aged two and older, screen time should ideally not exceed two hours per day, though adjustments should be made based on the child's learning needs.