護眼的十一大疑惑

這段時間比較忙。上個月的Zoom 分享，現在才整理出來了。很多家長對孩子近視很擔心。這裏做了一些解說和解惑。 我們以前10歲才近視，現在孩子6歲就近視了。一年長75度到一百度，到成人了，那不變成1000度？在那個度數，視網膜會更脆弱，容易脫落，也不能做激光手術了。 那近視發展，可以停止嗎？

近視其實有三個原因，媽媽懷孕期營養影響/難產， 看近的小字和符號多/眼睛壓力多，或者雙眼不協調/視功能失調。

雙眼視功能失調可以是因為集中不夠，調節不夠或兩眼微小動作不同步。如果不治療好，近視會快加深很多。雙眼視功能失調可以做視覺訓練矯正, 減少近視發展。視覺訓練目前還可以做腦震蕩眼腦康複治療， 視覺上的學習障礙，和提高運動員的速度和反應能力 （耳聰目明）。視覺訓練在美國開始，現在在廣州中三眼科醫院有提供。在美國可以在COVD.org  上找，Boston Children’s Hospital 也開始做了。在加拿大可以在 visiontherapycanada.com 上找。視覺訓練通常由進修做眼腦發展和複建的視光眼科醫生 (Developmental and Rehabilitative Optometrist) 和他的視覺訓練員做。

如果近視是隻是由用眼多的壓力造成的，那視覺訓練就不夠效果。 要一直做下去才好。 這種情況，可以做OK 鏡，效果會好很多。做OK 鏡前，要找做眼腦發展和複建的視光眼科醫生詳細檢查，確認沒有雙眼視功能失調才有效果。

下麵是在家長群裏的問題收集和我的回答：

Q1. 青少年帶隱形眼鏡有什麽危害嗎？如果佩戴怎麽選擇？

Dr. Liang, 我以前是常說隱形眼鏡沒什莫傷害，這主要是我的病人沒有什麽感染的情況。其實在青少年來說，普通白天戴的隱形是比成人的感染多一些。在中國，也比北美的情況嚴重些。在北美，風險是1-2%而已。我每個病人都要做個Contact Lens Fitting, 新手要做個 contact lens teach, 教會他們好的，規範的佩戴和清潔習慣，就減少了很多感染和不適。Contact lens fitting 是由視光醫生做的，挑的隱形就比較適合孩子，以後再每年檢查的就基本很少感染。OK 鏡來說，是比較透氣的，是晚上睡覺的時候戴的。洗的幹淨和規範，就減少很多感染。

Q2. 青少年戴遠視眼鏡，需要防止近視嗎？遠視眼如何注意保護眼睛，維持正常視力？

Dr. Liang, 近視的人眼睛比較長，看到的都投影在眼睛視網膜的前麵。 遠視的人眼睛比較短，看到的都投影在視網膜的後麵。和近視是相反的。遠視的孩子需要每年驗眼檢查。 他們有些像有老花的人那樣，看近的，會不清楚，或者逃避看書。做驗眼檢查就可以看到他們的眼睛視功能會不會也受到影響了。

Q3. OK鏡的最佳佩戴年齡，激光手術針對近視者是一勞永逸的嗎？術後會有什麽副作用？20歲的女孩是佩戴OK鏡適合還是激光手術更適合？

Dr. Liang, OK 鏡6歲就可以戴了，到成人也可以戴。如果眼睛度數有穩定下來兩年了，可以考慮做激光視力矯正手術。副作用包括眼幹和晚上會有光圈。早點找個視光眼科醫生手術前的評估，可以減少很多風險。做完手術，每年驗眼可以減少副作用的影響。到40歲了，老花了，還是要戴眼鏡的。

Q4. North York 孩子17歲，視力左眼0.1、右眼1.0，是否最好要配戴眼鏡。如果不戴眼鏡，是否反而不能訓練0.1左眼？

Dr. Liang, 這個視力看來雙眼度數應該相差很大。這個情況該檢查一下弱的那個眼睛有沒有眼睛的病， 還有看看有沒有弱視。就好是配戴日拋的隱形，然後看眼腦發展的視光醫生(developmental and rehabilitative Optometrist)做視覺訓練 (vision therapy)。如果有弱視了，視覺訓練可以矯正回來。

Q5. 看電腦時，帶藍光眼鏡對視力有保護作用嗎？

Dr. Liang, 防藍光眼鏡對視力的保護不大，可能有1-2%的作用。你可以自己調低電腦的光線，減少藍光。個人定製的防疲勞的鏡片對視力的保護比防藍光眼鏡好10倍。視覺訓練對視力的保護比防藍光眼鏡好90倍，這些方案可以做，在眼腦發展的視光醫生那做就好。

Q6. 在家上網課時，選擇投影儀會比看電視、電腦對視力要好吧？

Dr. Liang, 如果家裏有條件的，是的，投影儀遠一些，減少對眼睛的影響。投影儀和電視一樣遠的話，那電視會清晰一些。越近，對眼睛的壓力越大。以前我們奶奶爺爺輩的，也是因為做針線活，讀書，近的活，影響了眼睛了，不然沒是沒有近視的。（能幫講解一下投影儀、電視、電腦、iPad 和手機這幾種電子對視力的影響嗎？ see above. 如上。）

Q7. OK鏡使用多久後需要更換？如果到期不換會有什麽後果？哪些品牌的護理液和潤滑液是適用於多數OK鏡的？

Dr. Liang, OK 鏡通常一年一換。它是有磨損的，雖然肉眼看不見，但還會在。今年疫情期，變數很大。因為在家看電腦，上網課的多了，眼睛近視漲快多了，有些眼睛會因度數改變要多換一些。 不換會影響控製近視的效果，白戴了。 洗鏡片的藥水，要雙氧水好一些。品牌的問題，請問視光眼科醫生，你去診所做OK鏡的話，都會和你說的。最重要的，還是護理鏡片的教育和好的習慣。這些，做OK鏡的醫生可以和孩子複習。

Q8. 孩子17歲，佩戴近視眼鏡五年了，這兩年度數維持在270度左右，原本每年檢查一次視力，今年因為疫情沒有檢，請問需要每年一檢和每年更換眼鏡嗎？

Dr. Liang, 安省視光眼科醫生協會建議一年找視光醫生做一次眼睛全麵檢查。疫情期用電腦多，眼睛變數更多，我建議更要檢查。檢查後，醫生會視情況建議鏡片或鏡框的更換。驗眼時請務必帶上眼鏡。

9. 眼部如何做訓練 ?

Dr. Liang, 視覺訓練是在美國開始。視覺訓練用腦科的原理，和物理治療的原理，來提高腦眼協調，和雙眼協調。大腦80%的容量都和視覺有關。視覺訓練其中包括， 提高大腦對眼睛的控製，提高眼睛回饋給大腦的信息，提高眼睛這個感官和大腦的溝通。譬喻，有些人是用右眼多的，有些人是用左眼多的。有些人看書兩個眼睛可能是不同步的，一個比另一個快，就容易造成看書跳字，或跳行。到了需要看很多書的時候，這些人就吃虧了。視覺訓練就可以平衡雙眼的速度，跟蹤，跳躍，調節，集中和分散，打開外圍視野的感應 （眼觀四麵）。視覺訓練還可以和聽覺，觸覺一起調和，提高反應能力和眼手協調 （提高眼睛和大腦的靈敏度）。由眼睛引起的學習時精神不集中，弱視和斜視的人，和腦創傷的人的都能通過視覺訓練康複回來。

10. 高中孩子-NorthYork, OK鏡清洗能詳細說明一下嗎？配眼鏡時技師說早上取下來直接放在雙氧水裏泡6小時後可以直接佩戴，取戴時可以用自來水，涼白開或是生理鹽水衝洗一下嗎，哪種水衝洗更合適？

Dr. Liang, OK鏡，我建議找視光眼科醫生配（contact lens fitting)，減少感染，效果也好很多。 在安省，第一次配戴的時候，醫生助手會詳細教你怎樣戴，和建立好的護眼習慣。在加拿大，視光眼科醫生(Optometrist) 是可以看眼病和開藥的，過敏了，感染了，都可以開藥治療。配鏡師(Optician)是不能/不會看病開藥的。視光眼科醫生學過眼睛病理學，治療過眼睛感染，是不建議你用自來水洗隱形眼鏡片的。如果用雙氧水裏泡6小時後，可以直接佩戴，不要用自來水。

11. 對於幹眼症有什麽眼藥水和方法可以緩解，人工淚液可以長時間使用嗎？

Dr. Liang, 眼睛感覺幹的，安省視光協會建議看眼科視光醫生做個詳細的全麵眼睛檢查，找出真正的原因來治療。眼睛幹有多種原因，譬如藥物，習慣，環境，荷爾蒙，雙眼不協調，或做的隱形，眼鏡不適合。有防腐劑的眼藥水會更刺激眼睛的，用沒防腐劑的好一些。如果眼藥水有防腐劑的，一天不要用超過四次。 如果用了兩個星期眼藥水都沒好回來，建議你去看眼科視光醫生好好檢查。

微信：yanl2014
油管: DrLiang Optometrist

梁豔玲醫生畢業於滑鐵盧大學,在七年內從滑鐵盧大學拿到了生命科學和視光眼醫科雙學位。期間，她去了美國的中部的白內障和激光視力矯正中心實習，作為交換生到香港理工視光係實習，和到廣州中山眼科中心實習。她有十多年視光眼科經驗。她曾是加拿大視光醫生牌照,臨床考試的考牌官。她也曾是安省視光醫生協會董事會成員。她還是Seneca College 和 Georgian College Optician (配鏡師） program的實習課程導師。她不隻是做一般的驗眼配鏡，梁豔玲醫生畢業後還參加最新的臨床視光課程培訓, 成為眼腦發展和複健的眼科視光醫生，給雙眼不協調的孩子，眼睛影響的學習障礙，和有腦創傷的人做眼科視覺訓練。梁醫生工作以外還做義工, 給本地的獅子會義舉籌款，做公益活動。梁醫生說粵語和國語,和英語。想看其他護眼資料，請訂閱梁醫生的Youtube油管號，DrLiang Optometrist，有中文字幕。

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Myopia progression, can it be stopped?

During my younger years, I was myopic near 10 years old. Kids are getting myopic around 6 years old now. If their vision changes -0.75 per year, it would easily reach -10.00 by adulthood. With that prescription, there are more risk with retinal detachment and would be harder to do LASIK refractive surgery. So can myopia be controlled?

There are actually three causes of myopia, by birth/nutrition, near work stress with small prints/symbols, and poor eye coordination. Poor eye hand coordination can be caused by poor convergence, poor accommodation and poor eye movements. If not corrected, myopia can get worse faster.  All eye coordination functions can be improved with vision therapy. Vision thearpy is also used for concussion, learning related vision disorders, amblyopia/strabismus and athletic sports performance, NHL player, Olympians and racing.  

Vision therapy is widely used in North America, especially in the USA. It’s available in many private developmental and rehabilitative Optometrist’ clinics. These specialty-trained Optometrists can be found on www.covd.org in USA, and www.visiontherapycanada.com. Vision therapy is also found in Boston children’s hospital, and now ZhongShan Ophthalmic hospital in Guangzhou, China.

If myopia is due to near point stress, vision therapy would not be very effective. You would have to continue at all times for it to work. In this case, then orthokeratology is the best option. It’s effective for the right candidate, and it’s great for sports. With orthokeratology, myopia progression is slowed by 40-50%.

Last month, I did a zoom meeting with local parents about myopia and eye health protection. Here are some of the topics we covered, most are around myopia. Parents are concerned that their kids are having myopia earlier.

Q1: What’s the danger of kids wearing contacts? How to choose a lens properly？ 

Dr. Liang: I used to say there is almost no risk with an OK lens. But some that came to me from having done with someone else did have a poor effect on eye movements, and sometimes more risk of red eyes and infections.  Contact lenses do have a small risk of infection, it’s about 1-2%. To get the right contact lenses, you need to see an Optometrist for an eye exam, and do a contact lens fitting for the proper size, power, and vision that you need for either work or play. The Optometrist would also train you properly for infection prevention. It starts with proper insertion, removal and cleaning. Good habits would reduce infection.  

Q2: For Kids who are farsighted, should they be concerned for myopia? How do farsighted people protect their eyes and keep good vision?

Dr. Liang: Farsighted eyes have their images projected to the back of the retina, it’s the opposite of nearsighted, where the image is projected onto the front of the retina.  They need to be checked at least once a year. Eye coordination needs to be checked, to make sure there is no effect on reading and writing. similar to those who have presbyopia.

Q3, What’s the best age for an OK lens? Is LASIK the best treatment for nearsightedness? What’s the side effect? For 20 years olds, is it better to do an OK lens or to do LASIK?

Dr. Liang: The use of an OK lens can start at age 6. Up till adult life. If the eye is stable for more than two years, then they can consider LASIK. LASIK is also not for everyone. It may cause dry eyes and halos at night for driving. Checking the eyes yearly after the surgery can reduce the side effects on you. You would still need reading glasses at age 40. It’s good to see an Optometrist for a personal assessment to see if they are a good candidate for LASIK. There are many factors involved.

Q4, a young adult in North York is 17 years old, one eye sees 20/200, one eye sees 20/20, should he wear glasses? If he doesn’t wear glasses, is it hard to train the eye with the worse vision.

Dr. Liang: It appears that the two eyes may have very different prescriptions. It’s best to check the eyes to rule out any eye diseases and amblyopia. These children are best served with daily disposable contact lenses and would need to do vision therapy to prevent the eyes getting more different. It can reduce their passion for reading and learning if the eyes are poorly coordinated. Please see a developmental Optometrist. A properly fitted contacts and vision therapy would help them use both eyes together. 

Q5, For computer use, do blue light blocking lenses have protection on vision?

Dr. Liang: Blue light blocking lenses don’t have too much effect, maybe only 1-2% reduction on eye fatigue. You can reduce the blue light yourself by lowering the brightness on display and screens.  Anti-fatigue lenses have 10x more effect than blue light blocking lenses. And vision therapy has 90x more effect than blue light blocking lenses for near work stress and fatigue. You can see a developmental Optometrist for a personalized pair of anti-fatigue lense’s for better eye protection.

Q6, When doing online courses, is it better for the eyes to use a projector than to watch TV or use the computer?

Dr. Liang: If possible, yes, projectors work better than near point computers or screens. It’s worse when it’s closer to your eyes. As our eyes are more relaxed from looking at far, from the hunting and gathering days. But for school work and future workforce, they would still need to use the computer. It’s better to train them in vision therapy, and give me good working habits to work with technology for today and the future. 

Q7, How often does one need to change the OK lens? What are the effects if not changing it frequently. Which brands work better for the OK lenses. 

Dr. Liang: OK lenses usually should change yearly. As their micro changes on the lenses that cannot be seen by the naked eye. However, this year, there is covid and some eyes change faster, so some eyes need to change more frequently. Our office uses a special RGP lens cleaning solution and non preservative hydrogen peroxide to clean. Use with care, ask the doctor as you proceed with the OK lens, as it can cause a chemical burn if used improperly.

Q8: My child is 17 years old. He’s been wearing glasses for five years. The last two years are around -2.75ds. We tend to check once yearly. This year, we didn’t check due to COVID, should it be checked yearly? Should glasses be updated yearly?

Dr. Liang: Eye exams should be done at least once a year for children.The doctor would make proper recommendations to change the lenses if deemed necessary. Please bring your glasses when you bring your children in to check their eyes.

Q9, How does one do vision therapy?

Dr. Liang, Vision therapy incorporates a series of exercises such as physiotherapy, to help the eyes move better separately, and then together from far to near, and from side to side. We were never taught how to use our eyes to see, but vision is what we do, not what happens to us. For example, some people use the right eye more than the left. Some people jump around with their eyes when they read or correct their essays. (I used to do that.) It includes training in pursuits, saccades, accommodation, vergences, opening peripheral awareness, integrating with other senses such as hearing, and touch, for better reaction time and eye hand coordination. You would get the training from the developmental Optometrist office once a week, and do 20 minutes of exercise at home every day. 

Q10, High school child in North York, Can you clarify how to clean OK lens? Optician said you should be able to put it into your eyes after using Hydrogen peroxide for 6 hours. Or you can use tap water, cold boiled water, or saline to wash. Which one should be best for washing. 

OrthoK is best done with an Optometrist, as the child need to be checked for eye infections or allergy in the eyes. I have seen many cases of red eyes from those who came to me after having lenses done with an Optician in Markham. Usually the Optometrist and Optometric staff would go through all the infection control with the student at the initial fit of the contact lenses, and the Optometrist would monitor frequently for risk of infections and allergies. But by all means, please do not use water at all. If you use hydrogen peroxide, it’s clean after 6 hours. You can just put the lens into the eyes, or use a type of eye drop before putting it onto the eye. 

Q11, For dry eyes, what kind of eye drops would work for relief?

Those with dry eyes should see an optometrist for an eye exam for relief. The cause of dry eye can be from medications, habits, environment, hormones, or poor eye coordination, or poorly made glasses.  It’s better to find out the real cause and fix it. Eye drops with preservative should not be used for more than 4x a day. Eye drops with no preservative can be used for longer. If you tried the eye drops for two week, and you are not getting better, you should go see the Optometrist for better care. Halloween is around the corner, please see an Optometrist if you want contact lens for Halloween. 

Reference:
Contact Lenses
https://contactlensupdate.com/2018/10/26/contact-lens-wearer-demographics-and-risk-behaviors-for-contact-lens-related-eye-infections/
20/20 Isn’t Everything
https://www.optom.on.ca/OAO/Patients/Library/20_20_isn_t_everything.aspx