Floaters- hate them, hate them

This video talks about a common and very annoying eye condition- floaters. I describe my own experience with floaters and talk about risk factors of having floaters. If you suddenly see new floaters or flashes of light, don’t delay, call you eye doctor and have your eyes checked, because 15% of cases may be associated with retinal tears and detachment. Check out my previous post about floaters: https://bostoneyeblink.com/2019/11/28… One of the risk factors of having floaters early is myopia, here is the list of videos that talk about myopia prevention and control. https://www.youtube.com/playlist?list…

Keratoconus- a creepy eye disease that affects the young

This article is also available in a podcast: https://spotifyanchor-web.app.link/e/C3O8RRhTsvb

Juan Ding, OD, PhD

The mysterious case of poor vision with contact lenses

A 38 year old guy came to see me to check his contact lens prescription. He got the final contact lens prescription from another optometrist in our practice in March, so about 8 months ago, and he could no longer see well with them. This is a red flag. In adults, prescriptions are typically stable for years. 20-40 is a stable and healthy period for the eyes, with relatively few diseases and certainly few fluctuations in refractive power of the eye. But our patient obviously has a problem despite his young, primal age. So let’s look at what’s going on.

He’s wearing biofinity Toric XR lenses. For those of you who are not familiar with it, this is a monthly disposable contact lens that corrects for high amount of astigmatism that most other regular contact lenses do not correct. Toric lens is a lens that corrects for astigmatism. Astigmatism is when the eyeball is not shaped perfectly like a soccer ball, but rather a bit like the American football, so different in terms of curvature on the two different planes. And that’s why people can get blurry vision with astigmatism and there are certain contact lenses, the toric contact lenses that can correct this. Right now his contact lens prescription is about -8 – 3.5, that means he has about 8 diopters of myopia as well as 3.5 diopters of astigmatism. As you can see that’s a lot. When I look at this previous record from March, he was wearing these contact lenses and his vision was about 20/30 with the correction. So that was not 20/20 either. And 20/20 is usually the standard healthy vision that we’re aiming for. Anyone without a notable disease of the eye should have the standard 20/20 vision, especially adults. Today his vision with the contact lenses is only 20/100 and he has over these contact lenses a very large prescription, another five diopters of astigmatism. That is really striking difference, and that should not happen with healthy eyes.

When I asked him, he reported that even when he first got the contact lenses, he was not really seeing all that well. And now it’s getting progressively much, much worse, to the point he could no longer work and it was difficult to drive. I asked him, “Are you sure you put the contact lenses in the right eye?” Sometimes patients would mistakenly switch the contact lenses for the two eyes and that can make things a little funny as obviously the two eyes will be using the wrong prescriptions for both of them. He said that he made sure of it. In the past, he did accidentally switch the two lenses and it was very blurry. He was able to recognize that and switch them back, and now this he was very sure he was using the right lens in the right eye.

I asked him to take off his contact lenses and started doing refraction again. It turned out he could not really see that well even with the new prescription. And the new prescription was markedly different than his current prescription back from March as well. So his glass prescription has also changed a lot. This is very strange. At this moment I was suspecting something funny on the surface of the eye because he does not have diabetes, which is another common cause of large refractive changes over a short period of time. A really quick way to test this is to check the red reflex on retinoscopy. I took up the retinoscopy scope, and this is a light that you can shine into a patient’s eyes and the red reflex would show up funny if there is anything irregular on the surface of the eye. However, nothing wrong showed up there.

I then took a look at his eyes under a microscope, a slit lamp. This is a lighted microscope that you can magnify and see fine details of the eye. I was looking at the surface of his eye and it looked really healthy. There was no notable dry eye. He’s got healthy tears as well. His cornea is completely clear and there’s no staining on them. There’s no opacity on the cornea.

I didn’t dilate his pupils and check the back of the eyes immediately. I could put some dilating eye drops in and check to see if there’s any disease in the middle or in the back of the eye. But I didn’t do that. With the dilation you have to put the drops in and that takes about 20 minutes for the pupils to get bigger. And patient’s eyes remain dilated for the next four to six hours. It can cause a lot of inconvenience. Obviously when it’s necessary, we have to do this. But he’s got to work afterwards and doesn’t want to get dilated.

So the next high yield exam is a corneal topography. This is a machine that draws a map, a very fine, high resolution, accurate map of the surface of the cornea that you may not necessarily see with just the magnifier or with a retinoscope. This test is quick. You just need to turn the machine on, patient looks into a bowl of concentric rings, and it takes a few seconds to take a picture for each eye. A minute later, it becomes apparent that there is something wrong going on in the corneal surface that I am not able to see with the other techniques. It is not very obvious. It is kind of subtle, but he’s got a condition called keratoconus. Figure 1 shows his corneal topography findings.

Figure 1. Corneal topography map of definite keratoconus in the right eye and possible keratoconus in the left eye.

What is keratoconus?

Keratoconus is a condition that affects the cornea of the eye, and cornea is the very surface of our eye, the clear thin membrane covering up the surface of the eye, and through that clear cornea you can see the iris, which is the colored part of the eye, as well as pupil, which is the small opening in the center of the iris. The front surface of the cornea is very important. If there’s anything irregular going on, your vision can be blurry. In keratoconus, the cornea undergoes degenerative changes through the years. It can happen very quickly over a short period of time, but it can also stay dormant for months and years. Keratoconus happens in about 1 in 700 people in the general population. So while it is not extremely common, it is also not a rare disease.

This is unfortunately a disease that affects the young people. Children as young as eight years of age can start developing keratoconus, but typically it happens in late teenage years and it can continue to get worse through the years. It happens to both eyes, but it can be asymmetrical, meaning one eye may be affected more. I’ve seen many people who have one eye completely normal 20/20 vision do not need glasses. The other eye with relatively advanced keratoconus.

But even in this apparently normal eye, if you do the corneal topographer map like what I did for the patient, you could see some problem for the normal eye. The apparent normal eye may also have sign of very mild keratoconus that’s fortunately off center- it’s often inferior, that means in the lower part of the cornea so it’s not in the visual axis. That’s why patients can see well, it’s not affecting their vision. But nonetheless, the disease is there and it may be dormant in the lifespan of a person, but it can also start progressing anytime.

Who are affected by keratoconus?

The cause of disease is still not clear, but people have seen that this runs in the family. Of course, it can happen to someone who has absolutely no family history of keratoconus, and it just starts with them. Or you can have parents with keratoconus, but the children can be completely normal. The genetics of this is not completely figured out, although some company is selling genetic tests for this condition.

It is believed that changes in the enzymes of the cornea are undergoing changes, bad changes that break down the collagen of the cornea. There are several layers of the cornea and some of these layers are fragmented and also becoming much thinner. There is sometimes a break or folds in these layers, and that also can lead to scarring and making the cornea very cloudy.

People have observed a few things that are associated with keratoconus. One of them is rubbing of the eyes, and many doctors believe that the rubbing mechanical action on the cornea itself can make it change in shape, thinner and make lose its normal property. And that certainly has its merits. Except, many keratoconus patients actually don’t rub their eyes. Some of them do, and they often have other conditions like allergic conjunctivitis. Their eyes are always itchy or dry and they feel uncomfortable and hence they always rub their eyes and that does make keratoconus worse. But many people actually rub their eyes a lot, but never develop keratoconus. This patient denies rubbing his eyes. He denies having itchy eyes or irritable eyes. And the surface of his eye as well as his conjunctiva do look pretty healthy. There’s no sign of inflammation there, so I have no reason to believe that he is lying.

Another association people have observed is that those with Down syndrome sometimes have keratoconus. Although, in my experience as a primary care optometrist, many Down syndrome patients have perfectly healthy corneas and majority of my keratoconus patients don’t have Down syndrome.

And another condition that’s associated with keratoconus is Ehlers-Danlos syndrome, a connecting tissue disorder. It kind of makes sense that their cornea would be weaker because cornea is made of collagen, which is the component of connective tissues.

Some risk factors have been proposed for keratoconus, including number #1 eye rubbing. And #2 is sleep apnea and this is an interesting one. Now with sleep apnea there is another highly associated condition, floppy eyelid syndrome. These patients’ eyelids are pretty loose. And when they sleep, they sometimes can inadvertently flip their eyelids and their cornea can be exposed to the pillowcase, resulting in corneal injury and eye pain in the morning. So connective tissue disorders may be the underlying cause of floppy eyelid syndrome as well as sleep apnea, and that could also be the underlying cause of keratoconus.

Retinitis pigmentosa can also be a risk factor for keratoconus. This is a condition that I will talk in details another time.

Why is keratoconus sometimes missed by eye doctors?

It is not easy to diagnose keratoconus, especially in the early stage. Like I mentioned, I try using retinoscopy and that’s one way to diagnose keratoconus. Typically you would see a scissor reflex when you do the retinoscopy procedure. There are two lines crossing with each other. However, that may happen in intermediate or above level of keratoconus. In early stage it may not show up that well.

Other methods include a slit lamp exam. Sometimes you can see folds in the deeper layer of the cornea. Sometimes you can see scarring and obviously that’s a much later stage and patients typically already see poorly before that. So that’s not really useful to diagnose early keratoconus. Sometimes you can see thickened nerves. Corneal nerves are typically not obviously visible even with the magnifier, but in keratoconus, for some reason the coroner nerves can be thickened. However, this is not a specific test for keratoconus because some normal people can have thick corneal nerves. Sometimes people can see a ring that is an iron deposit present within the epithelium of the cornea around the base of the cone. But it is also not always seen, especially those with early keratoconus.

People often classically cite Munson sign as a sign of keratoconus. That is a protrusion of the lower eyelid in downgaze, because in advanced keratoconus the surface of the cornea becomes almost like a cone, and so you can see that when people look down with that cone touching their eyelid, that is advanced keratoconus. You certainly do not see that in the early form.

So many of these are helpful, but none is the definitive sign of keratoconus, or they’re often not present or not obvious in early keratoconus.

To diagnose keratoconus, you really need to have high clinical suspicion and order that corneal topography test. This test is highly sensitive and it does show keratoconus much earlier than many of the other clinical exams. Classically in a corneal topography map view you will see steepening, which is usually indicated with red color whereas normal curvature is indicated with the green color. If you see the red color in the lower part of the cornea, that’s highly suggestive keratoconus. In early keratoconus, though, that redness may not be very obvious, and you have to rely on the asymmetry of the steepening of the cornea from the upper part of the cornea as well as the lower part.

In my patient, you will see that he has a lot of corneal astigmatism. So there’s redness both from the upper as well as lower part, but the lower part of the map is much more steepening than the upper part (Figure 1). This asymmetry is also a characteristic to differentiate from a regular corneal astigmatism, that would be equal amount of steepening from both the upper and lower that would be symmetrical (Figure 2) and that would not affect vision as much. And patients typically would see well with glasses correction and obviously with the contact lenses they would see well. A corneal map of more advanced keratoconus is shown in Figure 3.

Figure 2. Corneal topography map of regular astigmatism. This patient has high degree of astigmatism, but it’s regular, hence good vision with glasses. Note the symmetry between the red areas for the upper and lower halves in both eyes.

Figure 3. Corneal topography map of a patient with intermediate to advanced keratoconus. Note the red area is only evident in the lower half of the cornea, that is, the marked asymmetry between upper and lower halves in both eyes.

The corneal topographer in our practice can only capture map of the front surface of the cornea. There are some topographers that are able to map the back surface of the cornea as well. In keratoconus, it is observed that the earliest changes actually happen to the back surface of the cornea, before any visual symptom even shows up. If you go for a LASIK surgery evaluation, they will use this type of corneal topographer, because LASIK surgeons really want to catch the most hidden form of keratoconus as it’s a contraindication of LASIK surgery, more about this later.

Another reason eye doctors won’t think twice when giving out a new stronger prescription to a young person is the myopia epidemic. Myopia progression can produce the similar phenotype with kids updating their glasses every 6 months. Both conditions affect young people and myopia is so prevalent these days. Please check out my articles on myopia and myopia control. Sadly, myopia progression and keratoconus can certainly happen to the same person.

Patients with keratoconus typically have a history of good vision with glasses, just like those with myopia. Gradually their glass prescription changes over the course of years, until eventually, even with very high prescription of glasses they could not see well. They would turn to soft contact lenses that would work well for a period of time, but then vision may get worse again, until eventually the diagnosis of keratoconus is made.

What are the treatments of keratoconus?

And that’s the time when we should address this issue. And not just treat the symptoms, but actually treat the disease itself. Although this can be a degenerative condition that progresses overtime, there’s no inflammation associated with it. So anti-inflammatory treatment or medication will not be able to help in this condition.

The treatment of keratoconus comes in several different ways. First, we want to address the underlying cause. Without the treatment, keratoconus can be progressive, so early diagnosis is key. Once you diagnose the condition, you can start a treatment called corneal cross- linking to strengthen the cornea and stop the disease from progressing further. This procedure was approved by the FDA in 2016, so not that long ago, but it is the only way that can actually stop the disease from progressing. Note it does not reverse the disease, so it does not make the cornea better, or make the vision better. Patients will still need contact lenses and glasses to see better after the procedure. The cornea cross linking procedure really strengthens the cornea and renders the corneal stable from undergoing further degenerative changes over time. In this procedure, the corneal epithelium is taken out first and you would soak the cornea with drops of riboflavin. Then the cornea is exposed to UV light for 30 minutes. During this process the collagen inside the cornea will cross-linked with each other, therefore rendering the structure more stabilized. After crosslinking, when the eyes are stable, you can use contact lenses and glasses to see better. There will not likely be further change of prescription after this procedure.

Vision in keratoconus often cannot be corrected with glasses because the surface of the cornea itself is irregular. Regular soft contact lenses also cannot correct vision to a satisfactory level. Again, because any soft contact lenses put on the eye will drape over the irregularity. So the only way that allow more than mild keratoconus patients to see a little better would be a hard contact lens, whether it’s a small hard corneal lens, called a gas permeable (GP) lens, or a bigger hard lens called the scleral lens. These hard lenses will be able to mask the irregularity of the cornea and provide clearer vision. I have prescribed a lot of both types of lenses to keratoconus patients which make them see better again. Just yesterday a patient told me ‘I have never seen this well for a long time”, after he tried on a special GP lens.

The corneal gas permeable lenses are small, clear plastic contact lenses on the surface of the cornea, so it covers the black part of the eye only, and it can move freely whenever you blink. There’s a tear layer behind the lens as well as in front of the lens, therefore masking the irregularity of the cornea. It’s relatively easy to put in and take out, and easier to care for, but in the beginning of using the lens, many patients reported their eyes hurting with foreign body sensation, especially with blinking. And that’s understandable, because after all, you’re having a hard piece of plastic inside the eye that certainly is not comfortable. Fortunately, most patients get used to them after a few weeks of using the contact lens.

Scleral lenses are much bigger contact lenses. They are sort of like a small bow that hovers over the entire eye, so it actually touches on the white part of the eye. Therefore it does not hurt as much. In fact, it is quite soothing. You almost don’t feel that you have a lens inside the eye. You would fill the bowl of the scleral lens with preservative free saline, so from that aspect it is soothing to the surface of the eye. This lens is comfortable. It also corrects the irregularity on the surface of the cornea. However, the disadvantage is that it is much more expensive and it is a little more difficult to care for. And it is also more difficult to learn how to use it as you have to use a plunger to apply the contact lens inside the eye as well as the plunger to take it out. So the learning curve is a bit steep for patients.

As with any contact lenses, the corneal gas permeable contact lenses as well as the scleral lenses need to be carefully cared for and patients should never sleep in these contact lenses, they should always take them out before going to bed and soak them into the correct disinfectant solution and to be used again the next morning. Before touching the contact lenses, patients should always wash their hands with soap and water and make sure not to touch the lens with dirty hands. Patients should not go swimming, taking a shower or sleep in contact lenses.

Medical treatment sometimes is needed. A complication can sometimes develop in keratoconus called acute hydrops, this is a condition where a break develops in the inner layer of the cornea, allowing the fluid inside the eye to enter into the corneal stroma, causing severe edema and thickening, light sensitivity, decreased vision, tearing and pain. And this needs to be managed acutely because Hydrops can lead to corneal scarring. Providers will need to try to manage the pain and swelling. We can give patient a dilating eye drop that reduces the pain. We can give patient sodium chloride 5% ointment, which can reduce edema and improve vision a bit. It may take several weeks for Hydrops to completely clear. The patients may need to use this ointment for weeks or months before it finally resolves.

Unfortunately, sometimes advanced cases can occur. Corneal scarring can occur that no contact lenses will be able to restore vision, and to that end a corneal surgery needs to be done. A new cornea transplant can be placed in to replace the keratoconus cornea that has scarring.

Why is keratoconus an emotional eye disease?

I think keratoconus is a frustrating disease. It affects young people who have been seeing well in first two decades of life. And slowly their vision starts to get worse and this change, especially when early, is often missed. So they end up going to the eye doctor’s office a lot with multiple pairs of glasses with constantly changing contact lens prescription. And with frustration that their vision continues to get worse, if lucky and it is diagnosed early and cross linking is done, the cornea can be stable and hopefully patients can see much better to a normal level with the proper contact lenses or glasses, but many of the keratoconus patients need to use specialty contact lenses for all their life. To them, contact lenses are not an option. They have to use them simply because glasses will not make their vision good enough. They have to take care of the contact lenses all their life. That is a serious commitment. You have to follow all the rules. They’re not really good candidates for LASIK surgery. And in fact, sometimes latent keratoconus can become pronounced after a LASIK surgery procedure. I have seen multiple patients who develop keratoconus after LASIK surgeries. Although nowadays people are starting to do LASIK surgery together with cross linking and this may hold to be a promising procedure for keratoconus patients in the future that they may have surgery to correct their vision and do not have to worry about complications to their cornea.


To recap, early detection and diagnosis of keratoconus is really key in managing this disease. Once diagnosed, crosslinking procedure should be recommended. Even though most keratoconus progression happens before 40 years of age, I have seen patients that are progressing well after 45 years of age, so a cross linking procedure should be highly recommended to any patient if it’s still progressing, no matter their age. Hopefully keratoconus patients in this day and age can be diagnosed early enough with early intervention to prevent the need of significant corneal scarring and corneal surgeries, and hopefully glasses and contact lenses are all they need. Any young person with unexplained vision reduction should have the benefit of taking a corneal topography image to rule out keratoconus.

Diabetic Retinopathy Screening Using Artificial Intelligence in a Primary Care Setting


Diabetic retinopathy remains the number 1 cause of vision loss in working-age adults in America. Key to prevent this vision loss is early screening and detection. However, the screening rate remains low world-wide as well as in the US. For many Americans, there are several barriers to accessing quality eye care which include income, distance to the nearest clinic, and health insurance among other factors. Due to these barriers, it is important to improve the methods of screening for diabetic retinopathy, as well as the adherence to recommended follow up.  Recent studies have identified AI-based algorithms as promising tools for the screening and early identification of DR in at-risk individuals. Many different algorithms are being developed and the sensitivity and specificity of these algorithms needs to be evaluated before they can be clinically implemented. Further, there are limitations for the currently available AI that prevent them from being widely used clinically.

Our research aims to implement a novel AI that overcomes these limitations and improve diabetic retinal screening. We have partnered with the digital health company AEYE Health to test the diagnostic accuracy of a hand-held AI-assisted non-mydriatic funduscopic camera to be used in the primary care setting to screen at-risk individuals for retinal changes indicative of diabetic retinopathy. AEYE AI algorithm just received FDA clearance and we are in the final stage of implementing this technology in the primary care setting.

Losing half of vision is no small matter

Juan Ding, OD, PhD

Today I will tell the story of a patient who lost half of his vision. 

Disclaimer: patient’s name is an alias, but the case is real.

I saw John once a year for a few years, monitoring his glaucoma suspicion. Glaucoma suspicion simply means that one’s suspected to have, but does not really have glaucoma yet. He had good vision in general, but usually had many complaints about his vision, mostly that he had to use glasses which he never needed to wear before. 

Once he splashed some chemicals in his right eye while doing house work, and saw my colleagues multiple times while I was on vacation. According to the medical record, the chemical burn had resolved. He came to see me shortly after that.  

‘Doc, I cannot see with my right eye’. My thought was, maybe he was having scars on the cornea. But his cornea looked clear with only a faint scar in the periphery that could not cause vision loss. What’s also interesting was that both his eyes had similar vision. But he insisted that since the chemical splash, he could not see well in the right eye. Could the chemical have reached the back of the eye and caused retinal or optic nerve damage? With a dilated exam, as well as photos of the optic nerve, everything still looked as good as before. There was no apparent retinal or nerve damage.

So I ordered a visual field test. This test examines the periphery vision rather than central vision. I have a couple of his results from previous glaucoma testing, and one looked like Figure 1 A. The dark spots mean vision is less sensitive in that region. So in this graph (Figure 1A), there are only a few minor defects in both eyes.

Figure 1. Gray scale graphs representing visual field results. Each eye was tested separately and darker the spot means worse vision in that particular region. Copyright: Boston Eye Blink

When I saw his visual field results on that day (Figure 1B), I knew the worst had happened. I immediately called him and said, ‘John, you have to go to the emergency room right now.’ 

 As you can see now he had lost a half of vision on the right side, both for right and left eyes. So while he was complaining of not seeing in the right eye, he was actually not seeing on the right side.

This is called a hemianopsia, which means ‘half no see’, or losing vision in one half of the visual field. Vision with hemianopsia is somewhat depicted in Figure 2. This is not an eye problem. This is a brain problem. Specifically, there is a problem in the left side of the occipital cortex, a part of the brain that gets signals from the eye. 

Figure 2. Simulation of vision with right-sided hemianopsia. Everything to the right side of the visual field appears gray out or dark.

You see, our eyes ‘see’ things, but it’s really the brain that perceives the action of ‘seeing’ and gives meaning to it. When the brain suffers damage, both eyes will lose vision on the same side. But often patients will perceive the right side of vision loss as vision loss in the right eye.

And one of the most common causes of such brain damage is a stroke. Especially in a patient like John who has high blood pressure and heart problems. John had a history of congestive heart failure and had a pacemaker. 

‘But I am not having a stroke. I feel fine.’ John said. I asked for several other symptoms, such as weakness or numbness on one side of the body, slurred speech, difficulty walking, and so on. He denied all of it. 

He had been to the ED before, it was not a pleasant experience. He sometimes waited for 8 hours and just left before being seen. 

I get that. But this time it is different. Hemianopsia can be the only symptom of a stroke. I managed to convince him to go that day. I also called his PCP to check up on him to manage his high blood pressure.

In the subsequent weeks, he developed other stroke symptoms including weakness in his leg. 

I saw John again after 2 months. Needless to say, John was very distressed about his vision problem. He’s bumping into things and felt unsafe to drive. He complained about the long wait in the ED. The head CT scan did not reveal much, but he could not do the MRI due to his pacemaker. His visual field looked like in Figure 1C above. Well, not much improvement, perhaps a little worse even. 

Research has shown that many stroke patients suffering hemianopsia recover partial or full vision within 6 weeks. He’s clearly not in the lucky team. If they don’t show any improvement by 6 months, it’s unlikely they will ever have improvement. About ⅓ of all stroke patients with hemianopsia will never recover or improve. I have seen some patients just like that, they permanently lose half of their visual field after a stroke.

I asked John to come back in 4 months, which will be 6 months post stroke, to check again.

This time his visual field looks like above (Figure 1D). It looked like he had a full recovery! I was relieved and felt very happy for him. I asked him, ‘how do you feel about your vision?’ I was surprised to hear him say, ‘Terrible. It’s getting worse.’ 

‘How come? Your visual field is much better. You are basically normal now.’

‘Oh THAT,’ he said, ‘yes that’s better, I can drive again. But my glasses are broken and I really cannot see anything for reading.’

You will be happy to learn that John now has new glasses and is seeing well. He’s seeing his PCP as well as his cardiologist to manage his high blood pressure. 

Help! My Cornea Keeps Breaking

A case of recurrent corneal erosion

Transcript for those of you who would rather read:

A middle aged female patient came in, referred by one of the ophthalmologists in our practice for dry eye treatment. She said, ‘Oh I did not know that you were an optometrist, I thought you were a dry eye specialist.’ This statement assumes that an optometrist cannot be a dry eye specialist. That is plainly wrong. However, I can only imagine that she is not alone here and it may represent a popular misconception. Contrary to what the public think, an optometrist does not only prescribe glasses or contact lenses, though these are certainly the bread and butter in our jobs. An optometrist can diagnose and treat most eye diseases, and many of us develop specialties such as dry eye, medically necessary contact lenses, low vision, vision therapy and pediatrics. For dry eye, there are probably more specialists that are optometrists than ophthalmologists. I may do another video in future about how to select the right eye doctor based on your needs and visual complaints. 

I said, ‘dry eye is a specialty that both optometrists and ophthalmologists can do. Tell me your problem and I’ll see if I can help you.’ 

Though she did have chronic dry eye in both eyes, it’s her left eye that she was mostly worried about. (You can learn more about dry eye in my previous video and blogs and I have linked them below in the video description. )

She initially had an injury of the left cornea 8 months ago because of using CPAP mask while sleeping, since then it had happened again and again, to the point she had to discontinue using CPAP. The cornea is the clear tissue on the surface of the eye and good vision relies on clear and healthy corneas. Dry eye and injury can both make this tissue sick and result in pain, tearing and poor vision.

Her first ophthalmologist performed a procedure to remove the faulty superficial layer of the cornea and put a bandage contact lens in to protect the eye. Unfortunately that resulted in a corneal ulcer, for which she had to go to the emergency room of a famous eye hospital in a different city. A corneal ulcer is an infection of the cornea, which can lead to permanent vision loss if untreated. One of the risk factors of developing corneal ulcer is wearing contact lenses, and some of the contact lens related corneal ulcers can be difficult to treat, especially with delayed treatment.

With intensive antibiotic eye drop treatment, the corneal ulcer resolved. But her nightmare of the cornea injury continued, she was having almost weekly recurrent corneal erosions in the left eye, waking up with eye pain. She could not sleep well and was afraid to open her eyes in the morning. 

So what is recurrent corneal erosion, or RCE? This is typically a tear of the superficial layer of the cornea, initially often from an injury, but subsequently can happen spontaneously. It often happens when people wake up in the morning, because a sudden opening movement of the eyelid can open up a previously weak spot in the cornea. In addition, many people have dry eyes overnight for various reasons, such as incomplete closure of eyelids, having heat or air conditioner on, using a cpap machine, etc. Having dry eyes predisposes the opening of the healed wound again. As a result, waking up with severe pain, tearing and light sensitivity in the eye is a common complaint for those with RCEs. 

How do you treat RCEs? First, it is imperative to keep dry eye under control, for the reason mentioned above. This is also the reason my patient’s ophthalmologist referred her for dry eye treatment. Second, special attention should be given to the enticing factor of the cornea wound. In her case, it would be the overnight incomplete eyelid closure and possibly the eye touching pillow or other things physically. 

She had already tried ointment at night which did not prevent RCE from happening. She used artificial tears during the day, but the relief was only temporary. She was not doing any warm compress because she needed to boil her eye mask for some minutes to reactivate it each time. She did take fish oil capsules. The fish oil and the stopping of her amitriptyline medication were the only things that seemed to be helpful to her. Yes, certain medications can cause dry eye and again you can find more information in my link below. She was using steroid drops while her cornea was healing but she could not use that forever due to side effects such as cataract and glaucoma. She tried various goggles but reported that when they moved at night she sometimes found her eye touching various parts of the goggles, which could make things worse. 

Careful examination of her eyes showed that she had meibomian gland dysfunction and ocular rosacea, which were contributing factors to dry eye. More information about these conditions can also be found in my previous blogs with the link below. 

Based on her past treatment, I recommended that for dry eye and MGD, she continue the artificial tears 4 times a day, but should buy a much easier to use eye mask which can be simply heated up in the microwave before use. She would need to do warm compress twice with 5 min each time daily. She would continue the fish oil, which was beneficial to dry eye. She could start restasis twice daily, this being an FDA-approved eye drop for chronic dry eye, but with the caveat that it could take up to 3 months to be effective, and it only worked in a small percentage of dry eye patients. In future, if her dry eye is still not controlled well, she would benefit from intense pulsed light therapy, which is unfortunately very expensive and not covered by insurance.

For RCE, I recommended that she use a large amount of ointment in the left eye at night, and put an eye shield on to prevent things from getting onto or into the eye. Some studies suggest that doxycycline can prevent corneal breakdown and reduce the frequency of RCE. So I prescribed that to her. She did have stomach upset previously when taking it for Lyme’s disease, but this was a reduced dosage and we will monitor GI side effects closely.

Patient was very thankful and I hope she got better. Long-term management is required for both RCE and dry eye. That’s it for now. Let me know your thoughts and comments. See you next time!

Links for dry eye and MGD: https://bostoneyeblink.com/2016/06/28/why-are-your-eyes-dry/


ocular rosacea: https://bostoneyeblink.com/2019/12/12/another-treatment-for-dry-eye-doxycycline/

systemic medications that are associated with dry eye: https://bostoneyeblink.com/2019/11/02/when-drugs-cause-dry-eye/

Secret to Stopping Myopia

I will share a secret that can lead to complete myopia prevention in this video. It’s simple, but not many people among the general public know about it. It sounds simple, but in reality is extremely hard to achieve.

If you don’t want to watch the video, here is the transcript.

Secret to stopping myopia

Hello, this is Dr. Ding. I am an eye doctor and today I would like to tell you the secret to stopping myopia.

Myopia affects 1 in 3 people on this planet, and people with myopia have increased risks of a host of eye diseases that may lead to blindness. No, it is not merely an inconvenience of glasses or contact lenses that can be fixed by lasik surgery later. It is a fundamental change to the eyeball that permanently changes the anatomy and robustness of the eyes that no lasik can fix. Lasik may make you lose those glasses, but your eyes are nonetheless the same ones with the increased risk of macular degeneration, retinal detachment, cataract and glaucoma. These are conditions that glasses, contact lenses, or lasik can not fix.

So now you know that myopia is bad, but why is myopia so prevalent? 

We can blame some of this on our parents. Some of them have genes that make it easier for people to develop myopia. For example, if parents both have myopia, then their kids will have a much higher chance of developing myopia as well. It’s a bit like tall parents will give birth to kids who will become tall adults eventually. Unfortunately, we really don’t have a way to choose our parents or our genes at this moment. So let’s find out what else is the problem. 

For hundreds of thousands of years, humans lived as hunter gatherers and/or farmers, which means a lot of time spent outdoors. 

And up until some two thousand years ago, humans did not really read. Computers came out only in the last century, as well as ipads and smartphones. With modern education and lifestyle, it has become the norm to spend the majority of wake time reading, writing, or looking at things at an arm’s length, most often in a room. 

And this is a big problem for our eyes. Human eyes are supposed to be emmetropic or just right by stopping growing after 6-8 years of age. However, the constant near work and lack of exposure to high intensity, full-spectrum natural light keep sending signals to our eyes to continue to grow, which leads to myopia. As a result, children’s eyes develop myopia which continues to progress up till early adulthood. In fact, this high stress and demand we put on our eyes make myopia grow even in people’s 30’s and 40’s. 

The sad thing about myopia is that it is not reversible, which means that once it forms, it does not reverse. It’s just like when you grow to be 6 feet tall, you don’t just shrink to 5 feet. 

The sadder thing about myopia is that it will continue to progress if nothing is done to stop the eye from growing. 

The saddest thing about myopia is that it happens so early in life that the people who have this happen to them, AKA children, are too young to be able to make a decision to live differently to make a difference. It is up to the parents, the teachers, the school and the society to tell them, hey, this is hurting your eyes and we have to do something to stop your eyes from getting bad or worse.

So what can parents do? First, we need to know that normal growth or kids’ eyes rely on a good amount of outdoor activities daily. Numerous studies have shown that 2 hours of outdoor activities daily prevent myopia from happening in the first place, and slow down myopia progression once it starts. 

What is so special about the outside? We don’t know for sure, but most likely it’s the enormous amount of light outside vs the comparably much dimmer artificial light inside a room. For example, on a bright sunny day, the light unit outside is up to 100,000 lux, even on a cloudy day it is about 5,000 lux, whereas in a well-lit room it is typically around 1,000 lux. In addition, natural light consists of a continuous spectrum of the visible light, whereas most artificial light sources have a different light spectrum. 

Another factor could be the openness of the outside environment. Unless closed, our eyes are constantly focusing on objects and scenes. This is done automatically without you trying. So your eyes have more chances to focus on things that are much farther away outside than inside a room. 

Back to parents’ responsibility of giving kids outdoor time. This has to happen early and consistently. You don’t start bringing your kids outside when they are 6 or 7, you start doing that when they are 1 or 2. Remember it’s the bright natural light that’s beneficial and not the exercises themselves, so working out inside a gym will not help their eyes, but walking or even sitting in the sun will do.

Sure please put on sunglasses or a hat to avoid UV damage to their eyes, but even when protected by sunglasses the eye still sees much more light than inside a house.

Again it is the bright natural light that is beneficial, so taking them to the park when it’s dark or really cloudy or raining will not help. It may be good for other things but not for myopia prevention.

What can schools do to help kids prevent myopia? Let’s face it, kids spend the majority of their day time at school, when the natural light is the best. So make recess count, make every child go out to the field during recess. Better yet, increase the time of recess. Maybe teach some classes outside. Promote walking to school and not driving. Build more windows to classrooms. 

What can our society do to help children’s eyes? Educate parents, teachers and children. Let everyone know about this ‘secret’. Promote this on social media, on TV and on radio. Make policies that mandate 2 hour of daily outdoor activities for schools, preschools and daycares. Screen children for vision problems. Subsidize health plans to allow children to have free eye exams. Give working parents special time off once in a while during the day to spend time with their children outside. Foster a culture that favors activities outside as an essential part of healthy living. 

There it is, the secret. It seems so simple, yet it is so hard to do. It is in every way against our modern lifestyle and civilization, where sitting in front of a computer all day long is the mode of productivity and success. Yet we simply have to do it, because after all, what is more important than our children’s vision and health?