隱形眼鏡為不少人帶來方便與美觀，但同時也常與「乾眼症」劃上關聯。不少人配戴後感到眼乾、刺痛或異物感，便懷疑自己是否得了乾眼症。好多病人都會問：「以前戴足成日 Con 都冇事，點解而家戴兩三個鐘就眼乾眼痛？」又或者：「我本身有乾眼症，仲可唔可以戴隱形眼鏡？」隱形眼鏡本身不一定直接造成乾眼症，但如果淚膜不穩定，再長期戴 Con，就好容易令乾眼問題惡化。
以前戴足全日 Con 都無事，而家戴兩三個鐘就眼紅、乾澀，甚至除 Con 時覺得「吸住」眼球好痛？或者你做完激光矯視手術（LASIK / SMILE）之後,視力雖然清晰咋,但眼睛卻總係有異物感,特別係朝早起身嗰陣？呢啲都係淚膜不穩定嘅警號。隱形眼鏡會吸走淚水，而矯視手術喺復原期會暫時影響神經反射，減少淚水分泌。如果你嘅瞼板腺本身功能不佳，呢啲因素就會令乾眼症惡化。好消息係，透過適當嘅治療同護理，好多人都可以改善淚膜質量，重拾戴 Con 嘅舒適，或者令矯視後嘅乾眼症狀得到緩解。
點解你會由「Con 友」變成「戴唔住 Con」？
好多人都有類似經歷：以前戴隱形眼鏡可以由朝戴到晚，舒舒服服。但唔知點解,佢一兩年開始戴唔住。可能你喺喺返到公司仲 OK，但到嗰下午就開始乾、開始紅、眼睛有好強烈嘅異物感。除 Con 嗰陣,鏡片好似吸實咗喺眼球度，要好用力先「啪」一聲揭出嚟,甚至會痛。
你可能會諗：「係唔係我對 Con 有問題？」於是你換咗另一個牌子、試咗日拋、試咗矽水凝膠，但問題仍然係度。其實，問題唔係出喺對 Con，而係你嘅淚膜。
隱形眼鏡對淚膜嘅影響
隱形眼鏡本身就好似一塊「海綿」，會吸收淚水。當你戴上 Con，淚水需要覆蓋嘅表面積增加咗，而且 Con 會不斷吸走淚水。如果你嘅淚水分泌本身已經唔夠，或者蒸發太快（因為瞼板腺功能障礙），佢 Con 就會變乾、變硬，開始磨擦角膜表面。
長期磨擦會造成：
角膜表面損傷
Con 好似砂紙咁磨擦角膜，造成微細嘅損傷（角膜上皮缺損）。你會覺得好痛、有異物感、畏光。
巨大乳突 狀結膜炎（GPC）
上眼瞼內側會長出好多細小嘅「乳突 」（papillae, 好似小粒粒咁），佢啲乳突 會令你戴 Con 好唔舒服，而且會分泌好多黏液。
角膜缺氧
雖然而家嘅 Con 透氧度已經好高，但如果淚水唔夠，氧氣傳遞都會受影響，角膜會缺氧，出現紅筋、水腫。
The tear film on the surface of the eye consists of three layers, each playing a specific role. If any one layer malfunctions, the tear film cannot adequately lubricate the eye, leading to dry eye syndrome.
In fact, experiencing symptoms of dry eyes is not a disease, but rather eye discomfort caused by external factors. As for dry eye syndrome, most patients will experience the following subjective symptoms, including:
The reason for these symptoms lies in the poor stability of the tear film in individuals with dry eye syndrome, making them prone to the various symptoms mentioned above. This occurs because the discomfort from dry eye stimulates the lacrimal glands, causing them to secrete excessive reflex tears. Simultaneously, patients become highly sensitive to wind and light, frequently experiencing temporary blurred vision.
How can you objectively determine if you have dry eye syndrome?
To accurately diagnose whether you have dry eye syndrome, the most important factor is, of course, a combination of symptoms and examination results. However, if you simply suspect you might have it and want to understand your risk, you can use the internationally recognized Ocular Surface Disease Index (OSDI) to perform a self-assessment for dry eye syndrome.
I. Eye Sensations Over the Past Week
at any time
Most of the time
About half the time
Occasionally
None
Dry
4
3
2
1
0
photophobia
4
3
2
1
0
Redness with blood vessels
4
3
2
1
0
疼痛
4
3
2
1
0
Foreign body sensation
4
3
2
1
0
Thick secretions
4
3
2
1
0
Blurred vision
4
3
2
1
0
Poor eyesight
4
3
2
1
0
II. Over the past week, eye discomfort has impacted the following activities:
at any time
Most of the time
About half the time
Occasionally
None
Not applicable
Reading
4
3
2
1
0
NA
Using a mobile phone/computer
4
3
2
1
0
NA
Night driving
4
3
2
1
0
NA
Watching TV
4
3
2
1
0
NA
III. Over the past week, my eyes have felt uncomfortable under the following circumstances:
at any time
Most of the time
About half the time
Occasionally
None
Not applicable
When the wind blows (eyes are sensitive to wind)
4
3
2
1
0
NA
Dry environment
4
3
2
1
0
NA
air-conditioned room
4
3
2
1
0
NA
Dry Eye Disease Scoring Method
OSDI = (Total score × 25) / Total number of questions
OSDI Score
Symptoms
0–12
No, it's normal.
13–22
Mild dry eye syndrome
23–32
Moderate dry eye syndrome
33–100
Severe Dry Eye Syndrome
If you complete this self-assessment and find your score is around 13 or higher, you may need to seek a more accurate examination. To confirm a diagnosis of dry eye syndrome, an ophthalmologist will typically evaluate you using an ocular surface analysis (OSA) device or perform a tear production test (Schirmer's test).
I. Ocular Surface Analysis (OSA)
The Ocular Surface Analysis (OSA) instrument is an advanced diagnostic method capable of precisely evaluating various aspects of ocular health, including the structural function of the tarsal plate, analysis of the tear film lipid layer thickness, tear break-up time, tear meniscus height, automated blink recording, and quantification of glandular disruption.
According to the above criteria, if a patient only experiences ocular symptoms but no changes in tear secretion are observed during an eye examination, it is diagnosed as dry eye syndrome.If it is merely simple dryness that resolves after applying eye drops, it does not constitute dry eye syndrome. This may simply be a case of eye strain, such as temporary discomfort, dryness, gritty sensation, light sensitivity, tearing, or blurred vision occurring after prolonged reading or computer use.
造成乾眼症的原因是什麼？
Dry eye syndrome has multiple causes, primarily related to the state of the tear film and the function of the lacrimal glands. These include insufficient tear secretion or poor tear quality. Therefore, dry eye syndrome can be classified into two categories:
Insufficient aqueous layer secretion is the most common cause of dry eye syndrome. This may result from age-related decline in tear gland function. Women are also prone to dry eye symptoms after menopause, which may be linked to hormonal changes in the body.Additionally, certain autoimmune diseases (such as rheumatoid arthritis and systemic lupus erythematosus), blood disorders (including lymphoma and leukemia), trauma, infections, autonomic nervous system dysfunction, and prolonged use of specific eye drops or medications can also lead to insufficient tear production.Long-term contact lens wear can also affect tear production. Contact lenses reduce corneal sensitivity, leading to decreased tear secretion and potentially causing dry eye syndrome.
II. Inadequate Sebum Secretion
Inadequate oil layer secretion is another common cause of dry eye syndrome. This typically results from eyelid disorders that impair the function of the meibomian glands in the eyelids, thereby affecting the outer lipid layer of the tear film. Consequently, tears cannot effectively remain on the surface of the eye, leading to dry eye syndrome.
Prolonged use of electronic devices such as smartphones and tablets reduces blink frequency, potentially leading to insufficient tear production and an increased risk of developing dry eye syndrome.
4. Extended Driving
The air conditioning and ventilation systems inside vehicles can dry out the air, accelerating tear evaporation and leading to dry, uncomfortable eyes. Simultaneously, prolonged focus on the road ahead to monitor traffic conditions causes the eyes to remain concentrated for extended periods, reducing blink frequency and further increasing the risk of dry eye syndrome.
V. Unhealthy Eating Habits
Omega-3 fatty acids are crucial for maintaining healthy tear production and reducing eye inflammation. A diet lacking in omega-3 fatty acids—such as insufficient intake of fish (salmon, mackerel, sardines), flaxseeds, chia seeds, and walnuts—increases the risk of developing dry eye syndrome.
VI. Individuals with chronic conditions or a history of eye injury
Many patients want to know how long it takes for dry eye syndrome to improve and what methods can provide immediate relief from symptoms. However, the improvement of dry eye syndrome depends on the individual patient's symptoms and the severity of their condition. Currently, the medical community primarily employs methods such as artificial tears, autologous serum, thermal pulsed therapy, and pulsed light therapy to help patients alleviate dry eye symptoms.
For more severe cases of dry eye syndrome, Lipidflow therapy may be administered. This procedure involves using a device to apply continuous heat at 40°C for 12 minutes while delivering rhythmic pulsations to massage the meibomian glands. This softens and unblocks obstructed glands, alleviating dry eye symptoms and preventing further atrophy caused by gland blockage, thereby improving overall eye health.
Are over-the-counter dry eye care methods effective?
To alleviate eye strain and dry eye syndrome, many people turn to supplements like lutein. However, while lutein can help filter blue light and prevent retinal degeneration, it does little to improve dry eye symptoms.
Additionally, many people mistakenly believe that dry eyes can be "cured" simply by using eye drops. However, eye drops only provide temporary relief from symptoms. Overuse of eye drops can actually interfere with the eye's natural tear production process, potentially leading to the development of dry eye syndrome.
How can dry eye syndrome be prevented or improved?
Instead of randomly trying the methods mentioned above, it's better to protect your eye health and avoid dry eye issues by adopting proper eye care habits and steering clear of bad ones.
When working or resting indoors, special attention should be paid to the humidity in the air to avoid the adverse effects of an overly dry environment on the eyes. Additionally, we should avoid direct exposure to the airflow from fans or air conditioners. Adjust the angle of fans or air conditioners to prevent direct airflow toward the eye area, or move away from the direct contact with the airflow whenever possible.
III. Supplementing Antioxidant Nutrients
Antioxidant nutrients are essential for eye health, as the eyes rely on light to form images. Consuming foods rich in omega-3 fatty acids—such as salmon, walnuts, and flaxseeds—can reduce inflammation and stabilize the tear film. Meanwhile, incorporating foods high in vitamins A and C—like carrots, oranges, and kiwis—helps combat free radical damage and protect ocular tissues.
IV. Supplement with Anti-Inflammatory Phytochemicals
Many daily habits can contribute to dry eye syndrome, so we should avoid them whenever possible and maintain a comfortable environment for our eyes. What methods can we use to prevent dry eye syndrome?
1. Avoid eye irritation When using air conditioning or electric fans, position the airflow away from your eyes and avoid directing it directly at them.
2. Take Appropriate Breaks Whether using electronic devices, working, or studying, remember the 20/20/20 eye care rule. Remind yourself to blink frequently, taking a 20-second break every 20 minutes to focus on an object 20 feet (approximately 6 meters) away. This reduces prolonged close-up and sustained eye strain, helping maintain long-term eye health.
3. Reduce contact lens wear time Due to reduced tear production in dry eye patients, wearing contact lenses may scratch the cornea and harm eye health. Wear time should be minimized, ideally to less than 8 hours per day.
4. Quit Bad Habits Avoid staying up late to allow your eyes to rest adequately. Additionally, refrain from smoking or exposure to secondhand smoke, as smoke irritates the eyes and contributes to excessive tear evaporation.
5. Dietary Habits Moderately supplement foods rich in Omega-3 or Vitamin A, such as choosing salmon, walnuts, and other foods abundant in Omega-3; additionally, carrots, spinach, and similar foods contain ample Vitamin A.
