Meibomian glands – to discuss or not to discuss. That’s the jovial argument that’s been dominating our office for the last three months.
My marketing team tells me it’s important to keep explanations about dry eyes simple. I, on the other hand, don’t want to talk down to our customers by shying away from technical explanations.
So what is all the fuss about meibomian glands anyway?
Today, most research suggests that meibomian glands are at the heart of the dry eye issue. In fact, optometrists and ophthalmologists agree that Meibomian Gland Dysfunction (MGD) is the leading cause of dry eyes (1). That’s why, if you have dry eyes, it’s important to know what’s going on with this particular piece of anatomy.
Let’s go through the basics:
The meibomian glands make meibum – a mixture of oils that contribute to the fatty layer of the tear film. Without meibum, our tears evaporate quickly, leaving the eye surface unprotected. And if the tears don’t lubricate the eyes correctly, that’s when your typical dry eyes symptoms – burning, tearing, redness, blurry vision – set in.
Besides keeping the tears from evaporating, the meibum is also important for increasing surface tension and protecting the eye from bacterial attack.
The meibomian glands are located behind the upper and lower eyelids, lined up like keys on a piano. Each gland is made up of multiple acini with a long duct running along the length of the gland.
At the end of the gland is a muscle called Riolan’s muscle. Every time you blink, that muscle squeeze out the oily meibum so necessary for keeping the surface of the eye healthy (2). If the duct of a gland becomes clogged, however, meibum builds up and the gland can eventually waste away.
There are a number of factors at work here. Aging, for instance, is one contributor. Between the ages of 20 and 80, the delivery of meibum from the glands decreases by 50 percent (2). Hormonal changes or chronic inflammation can add to this problem. Other factors, like medication, chemicals, wearing contact lenses regularly, cold weather, and having lasik or cataract surgery, also impact our likelihood of developing dry eyes and the severity of our symptoms.
One study by Suhalim et al. also points out that there’s a sort of chicken and egg question at the heart of the meibomian glands discussion. When the surface of the eye dries out (thanks to wearing contact lenses or looking at a computer screen for many hours a day, for instance), that dryness affects the function of the meibomian glands (3). At the same time, poorly functioning or clogged meibomian glands also cause dry eyes.
Quick sidenote on computers and dry eyes:
Wondering why staring at a computer screen for too long might contribute to dry eye symptoms? When we stare at a computer screen, we typically blink less than the we do normally. The less we blink, the less meibum gets sent to the tear film.
As mentioned above, meibomian gland dysfunction is the most common cause of dry eyes. So if you are experiencing dry eye symptoms, it’s a good chance your glands are not working properly.
However, in some cases and particularly in early stage of MGD, the meibomian glands may be getting plugged up without a person experiencing significant dry eye symptoms (4). That’s why, if you are considering lasik or cataract surgery, it’s important to ask your eye surgeon to evaluate your meibomian glands prior to your operation.
After all this explanation, you’re probably wondering why a blog dedicated to omega-3 would discuss meibomian glands.
Many dry eye treatments, like eye drops, only provide temporary relief from dry eye symptoms. Getting enough omega-3, however, can help calm the inflammation issue that’s fueling the Meibomian Gland Dysfunction.
How does omega-3 help? When you get the right lipid balance in your body, the meibomian glands are less likely to get clogged up. In addition, the omega-3s help improve the quality and composition of the lipids in the meibum (5). Finally, omega-3, which works on the same biochemical pathways as over-the-counter pain relievers, could potentially also help reduce inflammation and corneal pain.
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Re-reading my blog here, I get it, I get it…It’s hard to fit the whole discussion about meibomian glands into a quarter-page print ad.
But still, I think it’s important to know about the contributing causes of a health problem. Because when you’re aware, you can start treating not just the symptoms, but the underlying issue too. For your longterm health, that’s what makes all the difference.
1. Anterior Segment Section Symposium: MGD: The Science under the Glands. Academy 2014 Denver Handouts. American Academy of Optometry. 1 August, 2014.
2. Olennikov, Leanna, Cunningham, Derek and Whitley, Walter. Improve Your Understanding of Meibomian Gland Function —and Dysfunction. Review of Optometry. 15 May 2016.
3. Suhalim, Jeffrey L. et al. Effect of Desiccating Stress on Mouse Meibomian Gland Function. The Ocular Surface 12.1 (2014): 59–68. PMC. 26 June 2016.
4. Opitz DL et al. Diagnosis and Management of Meibomian Gland Dysfunction: Optometrists’ Perspective. Dove Medcical Press (2015): 59—69. 28 August, 2015.
5. Qiao, Jing, and Xiaoming Yan. Emerging Treatment Options for Meibomian Gland Dysfunction. Clinical Ophthalmology (Auckland, N.Z.) 7 (2013): 1797–1803. PMC. 9 September 2013.