Fake membrane

A man in his late 40s came in with blood shot and swollen eyes. 5 days ago while in the gym he rubbed his eyes after cleansers still on his hands. Since then each day both of his eyes were feeling worse with foreign body sensation, itchiness, pain and discharge. He went to urgent care 2 days ago, was given antibiotic drops and ointment, but felt it’s not helping. His conjunctiva (white part of eyes) were the most swollen that I had seen. Unfortunately I did not take a photo, but found one on the internet that quite resembled his eyes at the time as shown below.

Image 1. Conjunctiva chemosis (swollen conjunctiva). Image from https://images.app.goo.gl/V48FJXf32i9gdeov5

Cornea (black part of the eye) was clear. At the time I thought this was toxic/allergic conjunctivitis, so prescribed a steroid drop to use 4 times a day for 7 days. 

A week later, he came back, reporting improved symptoms (pain 3/10 from 5/10 previously), but still lots of discharge. This time, the swelling was gone, the redness almost resolved, but when I pulled his eyelid down, there were white pseudomembranes (fake membranes) in both eyes, more in one eye than the other. Below is again from internet, showing similar to what I saw.

Image 2. Conjunctival pseudomembrane, a white membrane developing inside the eyelid. Image from https://images.app.goo.gl/bUz4K3c7xtfaDYaYA

Now this made me rethink the diagnosis. Pseudomembranes are often seen in infectious conjunctivitis caused by nasty bugs such as Corynebacterium diphtheriae, Neisseria gonorrhoeae, Streptococcus pyogenes and adenoviruses, some of these are highly contagious. I asked whether anyone else in the household developed pink eyes, and he said no. He had no systemic symptoms or swollen lymph nodes, which were a good sign. Pseudomembranes can also be caused by toxic and allergic agents, and even foreign bodies [reference 1]. So at this point I was still going with allergic conjunctivitis, but these other infectious causes were now on the back of my mind, making me uneasy. So I stopped the steroid drops and switched to an antibiotic/steroid combo drop, as well as adding an antibiotic ointment at night. Of course, the pseudomembrane had to be removed otherwise he would not get better.

1 week later he came back, this time he’s much better, no discomfort, not much discharge, no swelling or redness. Exam revealed residual tiny papillae, and the membranes were gone! 

To summarize, pseudomembranes can be caused by infections, toxins, foreign bodies or allergies, and to treat it the underlying cause needs to be addressed, and pseudomembranes need to be removed promptly.


[1] Ho D, Lim S, Kim Teck Y. Pseudomembranous Conjunctivitis: A Possible Conjunctival Foreign Body Aetiology. Cureus. 2020;12(5):e8176. Published 2020 May 18. doi:10.7759/cureus.8176

Gray floater in an elderly lady

Floaters can be so common, yet not all floaters are the same. Here is another example.

An 84 year old nice lady came for an urgent visit as she started noticing a greenish gray floater in the right eye for 1 week. She did not notice any flashes. Her right eye saw 20/400 with no improvement with pinhole (this usually means that vision cannot be improved with glasses). Her left eye was able to see 20/30.

It’s impressive that she had not had cataract surgery yet, and only had a moderate amount of cataract. One look at her macula in the right eye revealed why she saw this gray ‘floater’. There is a blob of blood there as shown in images below. 

Figure 1. New membrane (arrow head) and bleeding (***) in the macula of the right eye.

The other eye only had mild drusens in the macula, indicating early age-related macular degeneration.

So this may be a case of very asymmetrical presentation of AMD with the right eye affected by wet AMD with acute bleeding and vision loss, and left eye only affected by mild dry AMD.

I referred her to a retinal specialist for treatment.

See my other articles on “floaters” and related eye phenomena.



Does ortho K increase risk of glaucoma?

The ortho K lens is popularly used to reshape cornea, correct vision and slow myopia progression. Read my previous post here (https://bostoneyeblink.com/2016/09/09/ortho-k-why-do-it-and-is-it-risky/)

People are often concerned about potential side effects or complications of wearing ortho K lenses. We previously discussed that corneal infection is a concern, but proper hygiene and care minimize this risk. It is a hard lens that touches on the cornea, will this have any effect on glaucoma or eye pressure of the eye? A colleague of mine recently saw an 18 year-old patient interested in ortho K for his myopia, who has a family history of glaucoma, and showing some questionable visual field finding himself. My colleague is worried about what ortho K may do to patient’s eye pressure and risk of glaucoma.

First of all, glaucoma is exceedingly uncommon among kids and young adults. Second, even if someone has glaucoma, it is not a contraindication for wearing ortho K lenses. Research has actually shown that wearing ortho K lenses overnight reduced eye pressure slightly [1, 2].

Of course, if you have glaucoma, you need to regularly see your glaucoma doctor to check eye pressure, health status of the optic nerve and visual field function, whether you wear any type of contact lens including ortho K lens or not. But people with or without glaucoma, if eligible for ortho K lenses, can certainly choose to wear them.


[1] M.R. Romano; A. Calossi; F. Romano; G. Ferraioli, Intra–Ocular Pressure After Overnight Orthokeratology, ARVO Annual Meeting Abstract, Investigative Ophthalmology & Visual Science May 2006, Vol.47, 2391

[2] Chang CJ, Yang HH, Chang CA, Wu R, Tsai HY. The influence of orthokeratology on intraocular pressure measurements. Semin Ophthalmol. 2013 Jul;28(4):210-5. doi: 10.3109/08820538.2013.768679. Epub 2013 Apr 29. PMID: 23627528.

Doc, my eyes still hurt, now what?

Recently a patient complained to me: ‘Doc, my eyes still hurt.’

I asked: ‘have you tried the artificial tears I recommended to you?

‘Yes, it doesn’t do any good.’

‘How many times did you put in a day?’

‘I just did that once and it did not work.’

‘I see. How about the warm compress?’

‘Not working either.’

‘How long did you do it and how many times a day?

‘Once or twice, I forgot.’

‘Are you taking the fish oil supplement?’

‘Yes. Did not feel any different.’

Here I have a patient who two months ago came to me for dry eye. He reported trying restasis from his previous eye doctor for months but no relief at all. Eye exam showed typical meibomian gland dysfunction (MGD) and poor tear film quality, without blepharitis or corneal staining. So this is a case of MGD-induced dry eye, that’s why I started him on eyelid warm compress 5 min x 2, and fish oil 1000 mg x 2 daily, with artificial tears as needed, up to 4 times daily. I asked him to follow up in 1 month. At which time he was not doing any of the things I asked, and of course his dry eye symptoms continued. After re-education, I asked him to do these consistently and follow up again in 1 month. He has probably done some of this now, but not consistently, and given up very quickly.

Rather than drilling him again for being more compliant with the treatment regimen, I offered him an alternative, which he clearly came looking for. I would like to refer him for a lipiflow treatment. I explained what it is, how it is done, and why it works. Then I told him that it’s not covered by insurance and may cost $1-2,000 for one session.

After a short moment of silence, he told me that he would like to give warm compress another try. And that he just started taking fish oil last week and would like to see if doing this for longer may help. I agreed, and asked him to return in 6 weeks to evaluate on progress.

No one likes having the dryness, foreign body sensation, redness, burning and tearing caused by dry eye. Fortunately there are effective treatments such as warm compress and artificial tears, and often these are enough to control dry eye symptoms. Unfortunately these treatments require consistent and long-term use. There is no cure for dry eye, which is a chronic condition and may require life-long management. When it comes to dry eye treatment, compliance is key. There are certainly those unlucky people who despite doing everything right still suffers from dry eye. But fortunately those are the minority.

For more information on dry eye and treatment, you can visit my previous posts and video.








OK镜,是一个硬的透气的隐形镜片,用于晚上睡觉时佩戴。镜片暂时性改变角膜的曲率(角膜是眼睛最前面那层薄薄的透明膜), 这样当第二天早上将镜片取出以后,会有十几小时内看东西清楚的状态,从而矫正视力,无需戴眼镜。



大量研究证明,OK镜确实能延缓近视发展。这里附上两篇综述,总结相关研究[1] [2],供学霸家长阅读。





OK镜是安全,不过由于OK镜是晚上戴的,有研究发现,OK镜的感染风险和普通晚上戴的隐形眼镜相同,都是0.077% [3],也就是说每一万戴OK镜的人里面有不到8个人可能发生感染。在验配者经过认证培训的前提下,使用经过FDA验证的镜片材料,只要使用者保持良好的护理习惯可以大大减少感染风险。同时父母的监督也很重要。另外佩戴者需定期就诊,根据医生建议更换镜片。


戴OK镜的确容易发生角膜染色 [4],但这些是角膜表面微小的缺陷,在干眼等常见眼表疾病中也会发生,这是戴OK镜需要定期检查的原因。长期佩戴OK镜,一切都正常的情况下,每年至少也要检查一次,观察眼表健康情况,检查视力。如果有严重的角膜染色,需要停止戴镜,治疗恢复后在医生的指导下重新佩戴[J2] 。





  • 注意卫生,接触镜片和眼睛之前一定要肥皂和清水洗干净手,擦手最好用不留纸屑的纸巾或不留纤维的毛巾,因为纸屑或者小的纤维可能会通过手传递到镜片上,然后进到眼睛里。
  • 晚上戴好镜片以后,需要清水彻底洗净眼镜盒,并风干。
  • 早上摘镜的时候,先用护理液在手心揉搓几下,然后放在新鲜护理液中,直到晚上使用。
  • 浸泡镜片的盒子每2-3个月更换一次。
  • 每3个月可以进行一次蛋白清洗,因为镜片上会不可避免沾上眼泪中的蛋白质等。推荐使用Menicon Progent(除蛋白护理液)。
  • 有条件可以每年更换一次新的镜片,即使镜片度数完全不变。


  • 有效控制近视发展
  • 只需晚上佩戴,白天完全无镜


  • 贵!国产的一只镜片大概3000-5000,美国进口的就要4000-8000了。不过,在美国一对镜片大概也在1000美元以上。
  • 麻烦!和普通软的隐形眼镜一样,必须每天戴、摘、护理; 如果不注意卫生清洁,感染的风险增大。
  • 疼!初戴起来疼、不舒服,但适应期过后,大部分人不再出现不适感。


1. Campbell E (2013) Orthokeratology: an update. Optometry & Visual Performance 1: 11-18.

2. Lipson MJ, Brooks MM, Koffler BH (2018) The Role of Orthokeratology in Myopia Control: A Review. Eye Contact Lens 44: 224-230.

3. Bullimore MA, Sinnott LT, Jones-Jordan LA (2013) The risk of microbial keratitis with overnight corneal reshaping lenses. Optometry and Vision Science 90: 937-944.4. Liu YM, Xie P (2016) The Safety of Orthokeratology—A Systematic Review. Eye & Contact Lens 42: 35-42.

近视怎么纠正和预防 (2/2)




这些方法都能矫正视力,但是并不能改变眼轴长度。目前认为,眼轴一旦增长似乎是不可逆的。幸运的是,现代的视光医学研究发现有几个方法可以延缓甚至停止眼轴继续增长。角膜塑形镜(orthokeratology, 俗称OK镜)是最有效的物理手段,而低浓度阿托品眼药水是最有效的药物方法。


OK镜于1994年FDA批准。临床研究效果显著,儿童使用两年眼轴增长能够减少45% [1];而且实验结果经得起重复 [2, 3]。目前临床应用广泛,不仅在研究中有着显著的效果,身边的例子也有着很高的成功率。我的一些视光医生朋友非常推崇。最让我印象深刻的是一个国内朋友自己的例子。他900度近视,他妻子接近2000度近视,所以他们很担心小孩的眼睛。当他们的女儿9岁时近视达到200度,经过研究他们带她去配了OK镜,戴了5年,度数没有变化!我知道OK镜每年可以减缓近视25-50度,但是这样的家族史,5年没有加深还是很惊人的。要注意的是,人与人之间的差别很大,的确也有少部分人效果一般或者没有效果。造成这种差异的原因以及我们怎么能够个性化的治疗近视也是现在研究的一个热点。

低浓度阿托品也眼药水也可以有效的减缓近视的发展,效果和OK镜类似甚至更加好一点点。阿托品虽然是一个用了很多年的药,它的控制近视这一目的目前还没有通过FDA批准。当前的研究表明低浓度阿托品眼药水在几年内持续使用是安全的 [4],但是远期副作用还没有数据。在美国,低浓度阿托品眼药水需要处方,并且只有特定的药房可以配制。






  1. 带孩子去眼科医生或者视光医生去做全面眼睛检查包括散瞳和眼底检查,确定度数,佩戴镜框眼镜。
  2. 不要以为不戴近视眼镜或者戴故意矫正不足的眼镜可以减缓近视发展,研究表明恰恰相反,近视矫正不足会加快近视发展[5]。
  3. 18岁以下的儿童应该使用抗碰撞的聚碳酸酯材料制作的镜片以保护眼睛。
  4. 当孩子达到一定年龄,可以尝试隐形眼镜。但是一定要注意正确的佩戴、摘取和清洗护理,否则有角膜感染的风险。
  5. 如果对减缓近视的发展感兴趣,可以在视光医生的指导下使用OK镜。低浓度阿托品眼药水也是一个选择,但是目前没有通过FDA批准,远期安全性未知,需要承担风险。
  6. 等孩子18岁以后,又多一个选择,可以做LASIK。



  • 实行用眼卫生(visual hygiene)。这本来是一个视觉训练的概念,但是用在防止近视照样有用。1)看书的距离不应该小于手指第二个关节和胳膊肘间的距离。2)记住20-20-20的规则。每看书或者近距离用眼工作20分钟,就看20英尺(大约6米)以外20秒。
  • 改进室内照明。昏暗的光线会造成视网膜上成像的模糊,加快眼轴生长。
  • 夜晚睡觉时不要开灯。规律的昼夜节律不仅有益身心健康,而且对眼睛的正常发育和正视化也是必要的。这一点,从刚出生的婴儿做起
  • 多花时间呆在户外。如前所述,最新的研究发现每天两小时的户外活动会显著降低近视的发生。




1.            Li, X., et al., Update on Orthokeratology in Managing Progressive Myopia in Children: Efficacy, Mechanisms, and Concerns. Journal of Pediatric Ophthalmology and Strabismus, 2017. 54(3): p. 142-148.

2.            Walline, J.J., L.A. Jones, and L.T. Sinnott, Corneal reshaping and myopia progression. British Journal of Ophthalmology, 2009. 93(9): p. 1181-5.

3.            Chassine, T., et al., How can we prevent myopia progression? European Journal of Ophthalmology, 2015. 25(4): p. 280-5.

4.            Wu, P.C., Y.H. Yang, and P.C. Fang, The long-term results of using low-concentration atropine eye drops for controlling myopia progression in schoolchildren. Journal of Ocular Pharmacology and Therapeutics, 2011. 27(5): p. 461-6.

5.            Smith, E.L., 3rd, Optical treatment strategies to slow myopia progression: effects of the visual extent of the optical treatment zone. Experimental Eye Research, 2013. 114: p. 77-88.

Where is the pit?

Juan Ding, OD, PhD

Our central vision is seen by a structure called macula in the retina, and the center of the macula is called a fovea. Normally there is a pit dipping down at fovea as shown in Figure 1 below, and this is important for normal central vision.

Figure 1. Normal foveal pit indicated by the arrow.

Yesterday I saw a kid that had abnormal, or under-developed fovea.

This 6 year old boy came with his foster mother. He had fair skin, blond hair and was very light-sensitive. Mom never noticed anything abnormal, but he failed the vision test at his pediatrician’s office and that’s why they came here. 

His vision was 20/50 and 20/40, normal eye alignment, minimum refractive error, but after cycloplegia about +4.00 of hyperopia. At any rate, this hyperopia should not cause reduced vision at his age. So what can it be?

Interestingly when I looked at his retina I could not see a foveal reflex. And the retina was really light in terms of pigment. I attempted OCT and with some luck, managed to get photos from this well-behaved 6 year-old. It is apparent that his macula is lacking a normal foveal pit (Figure 2, right and left eye, respectively). 

Figure 2. Lack of a foveal pit in right and left retinas in our patient.

I gave this a tentative diagnosis of ‘fovea hypoplasia’. This condition can be seen in ocular albinism (lack of melanin) or aniridia (lack of iris), or it can happen as an isolated condition. He has normal eye structures everywhere else. Combined with a blonde fundus and extremely fair skin, I do suspect albinism. But he has no nystagmus, and vision is very good if he does have albinism. Since he was adopted, we do not know much about his family history. Mom adopted him while he was 18 months, and noted good health and normal developmental milestones up to now.

Given moderate to high hyperopia, I gave him a prescription of reading glasses. I referred him to his pediatrician to consider genetic testing.

近视怎么纠正和预防 (1/2)

在中国,据统计2014年7 到 18岁的人群中近视发病率高达 57.1% [1]。 今年新冠导致大量儿童蜗居在家,网课成为学习的主要手段。恐怕接下来会迎来一波新的近视高峰。为什么近视这么普遍?有什么办法可以纠正或者控制近视的发展?












  1. 不能当飞行员
  2. 找不到男/女朋友

抛开玩笑,很多人觉得近视没什么大不了的,无非就是戴眼镜不太方便,况且现在还有各种隐形眼镜和激光手术。但是近视,尤其是高度近视(大于600度),由于眼轴的增长,会增加各种眼睛疾病的风险,包括视网膜脱离,巩膜新生血管,白内障,青光眼和黄斑萎缩 [2],这些疾病可以造成永久性失明。由于近视的发病率非常高,而1/5的近视是高度近视,算下来非常可观的人数有着这些永久失明的风险。而戴眼镜和激光手术并不能降低这些风险,原因是眼轴长度并未得到改变。



  1. 家族历史。父母双方都近视的孩子的近视风险是父母双方都不近视的孩子的2倍还多。这个很好理解,基因的作用不容忽视。另外还有一些环境因素,比如近视的父母一般看书时间长,孩子也容易更喜欢看书。
  2. 近距离用眼的时间。工作性质、教育程度等等,这些不言而喻。
  3. 6-9岁时的眼睛屈光度。乍一看这点很奇怪。事实是,婴儿刚刚出生时的眼睛平均屈光度为200度远视(有很广的范围,从600度近视到1100度远视,但是大部分新生儿集中在200度远视左右),注意是远视而不是近视。然后在18个月的时候这种人与人之间巨大的区别就基本消失了,大家都差不多稳定在125度远视,这一过程叫做正视化(Emmetropization)。正视化是指眼睛生长发育达到正视,眼睛的聚光能力和眼轴的长度吻合的状态。可以想象,如果按照古代狩猎和畜牧的生活方式,人眼睛的这个度数就定了,直到病死饿死或者被老虎吃了。我们无从考查古代人的眼睛度数,但是一个非常有趣的例子是巴西亚马逊热带雨林的一个部落,至今没有太多的被现代文明侵入。我的一位老师,在近视研究领域内的一位先驱,曾经去那个村子考察当地居民的眼睛屈光度。在这个几百人的村子里,平均屈光度为75度远视,只有4个人有大于100度的近视。这四个人中,两个是村子里唯二的大学生,职业为老师,经常阅读;一个从儿童时代起就做裁缝;还有一个是个出生就高度近视的先天盲人。

由此可见,我们绝大多数人生来都不是近视眼,不幸的是,文字出现,书籍出现,ipad出现。现代人类的近视大概从7-9岁开始,每年增长100度;或者如果从10-13岁开始,则每年增长较慢,大约50度。近视的增长一般在17-23岁停止,但是像我之前在近视激光手术文章里讲的,成年人也可能会有缓慢的近视发展 — 多谢现代人的生活方式。

统计发现,6岁时候的眼睛屈光度如果是75度远视,那么将来近视的风险大为降低;相反,如果低于75度远视的话,则近视风险升高 [3]。

  • 种族: 近视青睐系数亚裔大于白人大于黑人 [4]。具体和基因还是文化、环境的差异有关,不得而知,可能都有关系。
  • 户外活动时间。最新的研究表明,户外活动,不管是运动还是静坐,不管是远眺还是读书,都会减少近视发展的几率和程度[5 , 6]。具体的机制是什么?加强了昼夜节律,更多的眺望了远处,在户外阳光下通过小瞳孔视力更加清晰,紫外线的照射,强烈的户外自然光促使视网膜合成多巴胺?还是由于维生素D的合成?现在还不清楚,也许是多种原因吧。
  • 规律的昼夜节律对眼睛的正常发育和正视化是必要的。婴儿期和儿童期晚上睡觉开夜灯会增大日后近视的风险。研究表明两岁前在黑暗中睡觉的婴儿后来只有10%的近视;那些开着夜灯睡觉的孩子后来有34%的近视;而那些开着正常灯睡觉的小孩后来的近视率有55% [7, 8]。


1.            Dong, Y.H., et al., [Prevalence of myopia and increase trend in children and adolescents aged 7-18 years in Han ethnic group in China, 2005-2014]. Zhonghua Liu Xing Bing Xue Za Zhi, 2017. 38(5): p. 583-587.

2.            Wu, P.C., et al., Epidemiology of Myopia. Asia Pac J Ophthalmol (Phila), 2016. 5(6): p. 386-393.

3.            Zadnik, K., et al., Ocular predictors of the onset of juvenile myopia. Investigative Ophthalmology and Visual Science, 1999. 40(9): p. 1936-43.

4.            Hyman, L., et al., Relationship of age, sex, and ethnicity with myopia progression and axial elongation in the correction of myopia evaluation trial. Archives of Ophthalmology, 2005. 123(7): p. 977-87.

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Juan Ding, OD, PhD

This case is from one of my favorite patients. He first came to me as a referral from his ENT (ear, nose and throat) doctor, because he complained about dry eyes since his facial nerve palsy on the right side. His ENT doctor was not the one to diagnose facial nerve palsy of course, but since he was undergoing several sinus surgeries he happened to mention this during one of the visits. 

In his initial eye visit, I noticed that his vision was not able to be corrected to 20/20 by glasses, and he had a large amount of astigmatism. Retinoscopy showed scissor shaped light reflex, and slit lamp exam showed steepening cornea with prominent nerves and the right cornea actually had a mild scar. Corneal topography later confirmed keratoconus in both eyes, more so in the right eye.

Keratoconus literally means a corneal cone. Cornea is the front transparent layer of our eyes, and it is usually a regularly shaped dome like in the image on the left (Figure 1). But in keratoconus, the cornea gradually becomes thinner and thinner, and bulging more and more like in the image on the right. Because now the cornea is irregular, vision is blurry, even with glasses often still not good, since glasses do not correct this irregular surface of the cornea. Even regular soft contact lenses will not do much in this case because the soft lens material will just drape over the irregular cornea and still showing the irregular optics.

Figure 1. Normal cornea and cornea with keratoconus. Image from www.allaboutvision.com

Fortunately certain rigid contact lenses called rigid gas permeable (RGP) lenses can correct vision. These are stiff and can mask the irregularity of a keratoconus cornea. These are typically small, and often very uncomfortable especially in the beginning while the hard lens rubs against the surface of the eye and the eyelid.

Another type of lens to correct vision for keratoconus is a scleral lens (Figure 2). This is a large lens that sits on the white part of the eye called sclera, therefore causing minimum discomfort to the eye, and it corrects vision because the lens vaults over the irregular cornea to mask its imperfection.

Figure 2. How scleral lens corrects vision in keratoconus. Image from https://visualeyesboca.com/scleral-lenses/

Back to my patient, I initially fitted him with special RGP lenses designed for keratoconus, but due to advanced bulging, these lenses were unstable on the eyes and often popped out when he moved his eyes around or blinked. I then fitted him with Jupiter scleral lenses. These are very simple and easy on the patients as they are a relatively small scleral lens and easier to insert for beginners. However, in his case, the fitting was not ideal because the edge of the cornea kept being pressed close to the back surface of the lens. This is not good in scleral lens fitting, as it may not leave enough space for the cornea to breathe. I then switched to BostonSight scleral lens design, which is larger and more easily vaults over the entire cornea. He was very happy about his vision, with the right eye seeing 20/25 and left eye seeing 20/20. He told me that he ‘hasn’t seen this well since 16’- that was probably when he started developing keratoconus. He’s now in his early 40s, and this was the first time he heard of keratoconus. 

Keratoconus is a condition that affects about 1 in 2,000 individuals. It usually starts in teenage years or early 20s, but can happen as early as 8 or 9 years of age. It tends to get progressively worse until stabilization in the mid 30s. There is often a family history, but not always. Both eyes tend to be affected, though one eye may be much worse than the other. We do not know the cause of the disease, but one modifiable risk factor is rubbing of eyes. So I always ask patients not to rub eyes. While it is progressing, an effective treatment called corneal cross linking can stabilize the cornea and halt the worsening of the condition. This procedure is typically done by a corneal specialist. Once cornea is stable, these special contact lenses such as RGPs or scleral lenses can often help patients to see what they used to be able to. Any keratoconus patient should have at least two types of eye doctors, one a corneal specialist, and one an optometrist who fits specialty contact lenses for keratoconus.

I feel like there are rocks in my eyes

by Juan Ding, OD, PhD

Today I had an urgent visit from an established patient. She’s in her early 50s, and has a medical history of high blood pressure, anxiety and depression. Regarding her eye history, she had narrow angles, which means she is at risk of developing a type of glaucoma (angle closure glaucoma), and for that she had laser peripheral iridotomy (LPI) before. This procedure allows fluid to communicate in the front chamber of the eye, preventing closure of the drainage system of the eye (the angle) thereby preventing high eye pressure from happening which can cause glaucoma. 

She was very anxious because since she started a new antidepressant, desvenlafaxine (Pristiq), 3 months ago, she started feeling like there were rocks in her eyes, blurry vision, more migraine and her blood pressure went up. Desvenlafaxine is a serotonin-norepinephrine reuptake inhibitor (SNRI), and it may cause blurry vision and angle closure glaucoma. She was very much aware of her narrow angles and worried that it’s causing glaucoma in her eyes. On her psychiatrist and pharmacist’s recommendation, she stopped the medication 2 days ago, but was now suffering from serotonin withdrawal syndrome. Her psychiatrist prescribed prozac as a transition drug, but wanted to make sure her eye pressure was not elevated. She had the medication in her car, and if the test was normal she would go and have her first dose. If not, she would not be able to start this new medication.

Fortunately, eye exam showed that she had normal eye pressure, and that her LPI was still working and her angles were open. So she was cleared to go on with another antidepressant.

But her eyes were dry, and this explained her sensation of ‘rocks’ in her eyes. She did try refresh artificial tears and felt it immediately helped her symptoms. I advised her that she could actually use these artificial tears regularly, up to 4 times daily, as long as she’s feeling the dry eye symptoms.

All too often, antidepressants and other medications cause dry eye. It’s not only uncomfortable, in some cases, causing extreme eye irritation in patients, who are anxious and depressed to begin with; but it can also cause blurry vision because of disrupted tear film. Anyone taking antidepressant is at risk of developing dry eye, and may try some OTC remedies first, like artificial tears, before visiting their eye doctors. Glaucoma is a much more rare side effect, but anyone with a history of narrow angles or glaucoma suspicion should be very careful- it’s best if they visit eye doctors routinely while on certain antidepressants. In severe cases of recalcitrant dry eye and/or glaucoma, an alternative medication may need to be considered.