Eye irritation due to the hairs on your eye lids:
Trichiasis or ingrowing eye lashes, is a common cause of eye irritation, this condition is due to malpostion of the eye lashes. In this case some or most of the lashes point inwards, not outwards. This malposition of the lashes has many causes, the most common one is just a few that are growing the wrong way for no sinister reason. These ingrowing eye lashes can be removed with the use of a small set of foreceps and a microscope by an Optometrist. The Optometrist will check the front of the eye at the same time using a special dye, fluorescein. This is to check for any abrasion that may have occured. The abrasion due to trichiasis may be on the cornea and or on the conjuctiva of the eye. If the eye is abraded significantly an antibiotic ointment may be needed. The Optometrist will advise accordingly, removal of ingrowing eyelashes is paid for by MECS.
Trichiasis / ingrowing eye lashes is commonly seen in older patients, over 75, especially of the lower eye lid margin. The eye image below shows an older right eye with this condition, trichiasis secondary to entropion. It can sometimes be treated with some tape to pull the lower lid down back into position. With the lid pulled down and the lashes again away from the eye there should be reduced discomfort. With no pain or reduced discomfort there is less lid spasm and less lid contraction. A bandage contact lens can also be fitted on a temporary basis. Again to reduce discomfort mainly to the cornea and reduce lid spasm.
Some eye lids actually have two rows of ingrowing eye lashes, one outwards and one inwards. This is caused by a mutation of the FOXC2 gene. And is called congenital distichiasis. The image below shows an upper eye lid with larger normal lashes and a smaller row of lashes just below, indicated by the arrow.
Malformation of the eye lid causing ingrowing eye lashes:
If the eye lid is injured or diseased the edge of the lid can change shape and be malformed. This malformation can cause the eye lashes to point in a different way. If this is due to long standing scarring from injury or surgery the lash can just be pulled out. Eye lash removeal like this is called epilation. However if the malformation of the lid is relatively recent the cause of the change in lid postion needs to be assessed. The image below shows a lower eye lid with a growth. The growth has caused the eye lashes in that area to chnange direction. A change in direction of the lashes can cause abrasions to the cornea.
Below is an image of an abraded cornea, there can be many causes, trichiasis is one possibility and dry eyes is another.
Chronic blepharitis can cause Trichiasis:
Blepharitis is an inflamation of the edges of the eye lids. This is usually caused by an infection or by demodex. As a result of Blepharitis the lid margin can become distorted. A distorted lid margin can cause the eye lashes to point a different way. If the eye lashes start to point inwards towards the eye then this is called Trichiasis.
Trichiasis caused by Trachoma:
Trachoma is a severe eye infection found usually in developing nations. It causes scarring of the inner lining of the eye lid. This scarring causes the eye lid margin to distort and turn inwards. The inward turning of the eye lid margin causes the eye lashes to rub on the cornea, this is called Trichiasis. The mechanical rubbing of the eye lashes onto the cornea causes pain and abrasions. The abraded cornea eventually scars due to Trichiasis which in turn leads to loss of vision. This condition is quite straightforward to prevent and treat, it just needs to be done before the eye becomes scarred.