What is Entropion?
Entropion is a condition where the edge of the eyelid turns inwards. This could cause the eyelashes to point towards the eyeball, a situation known as trichiasis. Entropion is one of the most frequent irregularities with the position of the eyelid. This misplaced eyelid can damage the cornea (the clear front surface of the eye) and the conjunctiva (the thin, clear tissue that lies over the white part of the eye), leading to eye conditions like corneal abrasion (a scratch or scrape on the cornea), scarring, thinning of the cornea, or the growth of new blood vessels on the cornea.
Entropion can affect one or both eyelids. There are four kinds of entropion: congenital (present from birth), involutional (due to ageing), acute spastic (temporary due to intense eye or eyelid contraction), and cicatricial (due to scarring). Lower eyelids are often affected by involutional entropion whereas the upper eyelid is commonly affected by cicatricial entropion. The condition where the lower eyelid turns inwards is much more common than when it happens to the upper eyelid.
What Causes Entropion?
Entropion is a condition where the eyelid folds inward. It can be due to a variety of factors such as loose eyelid skin, weakened or detached eyelid muscles, previous eye surgeries, infections, inflammation, or birth defects. The most common cause of entropion comes from changes naturally occurring as we age. This happens as our eyelid tendons, which hold our lids in place, relax and the muscles controlling our eyelids weaken, causing the eyelid to misalign.
Some infections and inflammation can cause what is known as acute spastic entropion. This condition is most frequently seen following another eye surgery, specifically in patients who had unseen age-related changes in their eyelids before their surgery. What happens here is that the muscle that helps close the eye continuously contracts causing the eyelid to turn inward. This can lead to irritation of the eye, especially the cornea (the clear front surface of the eye), due to the eyelashes rubbing against the eye, further worsening the condition.
Cicatricial entropion, on the other hand, results from tightness of the inner lining of the eyelid, caused by scar tissue formation. Any factors that increase the tendency of forming scars can put a person at a higher risk of developing this condition. Some of these risk factors are previous burns, injuries, infections, or inflammation.
Risk Factors and Frequency for Entropion
As people age, they are more likely to develop a condition named entropion. Also, having the condition in both eyes is three times more likely than in just one eye. Furthermore, entropion tends to affect women more than men, which may be linked to women generally having smaller tarsal plates (a crucial part of your eyelid).
Signs and Symptoms of Entropion
Conditions involving the eyes can often show a variety of symptoms. These symptoms might include eye redness and discomfort, increased sensitivity to light and wind, drooping skin around the eyes, tearing from the eye, irritation, and lessened vision. Reduced vision is especially likely if the cornea, the clear layer at the front of the eye, is damaged.
There are specific tests used to diagnose an eye condition called involutional entropion. The snapback test involves pulling the edge of the eyelid away from the eyeball and seeing how quickly it “snaps” back into place. For the distraction test, the lower eyelid is pulled away from the eye, and the distance is measured. If there’s more than a 6 mm gap, that’s not normal.
A test using a device called a slit lamp can help check for eyelid retractor disinsertion, which is when the muscles that move the eyelid come loose. Some signs that this might be happening are:
- A white line under the membrane that covers the white part of the eye, caused by the leading edge of the loosed muscles.
- An unusually deep lower eye pocket.
- The lower eyelid sitting higher than normal, or reverse ptosis.
- The lower eyelid not moving as much as it should when looking downwards.
For a type of entropion called cicatricial, the lining of the eyelid often shows scar tissue. It’s often hard to turn the eyelid back out. On the other hand, in involutional entropion, turning the eyelid out is fairly easy. Spastic entropion typically develops after eye irritation or inflammation from surgery. Congenital entropion could be considered if the muscles that support the lower eyelid aren’t developed properly. This could create instability in the eyelid, leading to the eyelid turning in on itself.
Testing for Entropion
Typically, lab tests aren’t needed to diagnose a condition known as entropion, which is the inward turning of the eyelid. However, if you’re diagnosed with a form of entropion called “cicatricial entropion” which can be caused due to scarring, it’s crucial to test for infections or autoimmune diseases before your doctor prescribes treatment. This is to find out the real cause of the entropion for proper treatment planning.
If you’re diagnosed with ‘involutional entropion’ which is often due to the natural aging process, your doctor may measure your eye’s bulging with a test known as ‘exophthalmometry’. This assessment helps them to see if your eye is sinking back into your eye socket, a condition known as ‘relative enophthalmos’. This could be a contributing factor to the inward turning of your eyelid.
Treatment Options for Entropion
Entropion is a condition where the eyelid turns inward. This can cause the eyelashes and skin to rub against the eye surface, leading to discomfort and potential damage. There are different treatment options depending on the cause of entropion.
Assuming it’s not severe, the condition can often be managed with eye drops or artificial tears to soothe the eyes; this can provide relief from the irritation caused by the eyelashes. These simple measures can be quite effective, especially in cases of spastic entropion, which happens when the eyelid muscles contract abnormally. Sometimes, wearinc contact lenses can also help protect the eyes.
In some cases, Botox injections can be used to temporarily relax the overactive muscles in the eyelid, helping to alleviate the spastic entropion. If entropion is caused by other conditions like scarring (known as cicatricial entropion), treating the underlying condition should be the first step before considering surgical correction.
If the condition doesn’t improve or is severe, surgery might be necessary. Often it’s possible to do some of these procedures in the doctor’s office or at the bedside, and they can provide a more long-term solution. For instance, sutures, or stitches, can help correct the position of the eyelid, but this technique is generally temporary.
If the entropion is due to loose or sagging tissue under the eyelid, this can often be corrected by tightening it. This is done by making an incision in the skin or inner lining of the eyelid to access and adjust the tissue. In other cases, a procedure to tighten the corners of the eyelids might be necessary. Operators can also use tissue from another part of the patient’s body or a suitable substitute to replace any scarred or distorted tissue.
Although these surgical options involve more intervention than non-surgical options, they can provide a more permanent solution to the problem of entropion.
What else can Entropion be?
When dealing with Entropion (a condition where the eyelid turns inward), it’s important to distinguish it from other similar eye conditions. These include:
- Epiblepharon (an abnormal extra row of eyelashes)
- Trichiasis (the misdirection of eyelashes towards the eye)
- Trachoma (an infectious disease that can cause the eyelashes to turn inwards)
- Distichiasis (the condition of having an extra row of lashes)
