Dry eye is a disease of the front of the eye, whereas a disruption in our normal tear production and maintenance occurs.1 There are two main types of dry eye: aqueous deficient dry eye and evaporative dry eye.
Aqueous deficient dry eye occurs when too little tears are produced by the lacrimal gland located below our eyebrow.3 When we don’t have adequate aqueous tear production, our ocular surface becomes rough, causing burning, gritty, and scratchy eyes. Wearing contact lenses or having a history of previous eye surgery can contribute to this type of dry eye.4
Evaporative dry eye, also known as meibomian gland dysfunction (MGD), stems from the clogging of the meibomian glands inside of our eyelids. Our meibomian glands secrete meibum, the lipid or oily layer of the tear film. This tear layer helps to keep the other layers of the tear film in place. When our meibomian glands are clogged, our tears can evaporate easily, causing irritation.5
“Dry eye: symptoms, causes and treatments” by EyeSmart – American Academy of Ophthalmology
Dry eye can be associated with systemic disease, including diabetes, thyroid issues, arthritis, ulcerative colitis, and Sjӧgren’s syndrome.2 Dry eye can also be caused by certain medications, including antihistamines for allergies, high blood pressure medication, and anti-anxiety or depression medication. Dry eyes can also be caused by extended computer or digital screen work. It is important to take breaks when viewing screens up close for extended periods of time, as we blink less during these periods.11
Comprehensive eye exam: A comprehensive eye exam with a thorough medical history can help determine if systemic disease is contributing to dry eye.
Anterior segment evaluation: Extensive evaluation of the cornea, conjunctiva, eyelids, and tear film (front of the eye) are essential in diagnosing dry eye disease.
Fluorescein staining/tear break up time (TBUT): Fluorescein dye is placed on the surface of the eye to determine how quickly the tears are breaking up/evaporating.
Lissamine green stain: Stain that targets devitalized cells while ensuring to leave healthy cells alone.10
Rose bengal stain: Stains dead cells on the ocular surface, excellent for evaluating evaporative dry eye.10
Schirmer test: A paper strip is placed inside the eyelid for a few minutes to determine how much of the paper is wetted by your tears.6
TearLab: A device that determines tear osmolarity, which is the amount of salt in the tears.7
Meibography: Technology to photograph and assess the meibomian glands inside the eyelids.
Dry eye can be treated in several ways and depends on the type of dry eye present.
Artificial tears: Lubricating eye drops to supplement the tear film.
Warm or hot compresses: In the case of evaporative dry eye, heated compresses warm up the meibum inside our eyelids and allow for more optimal secretion onto the ocular surface.
Anti-inflammatory drops: Dry eye can also be treated with Xiidra and Restasis, which are both drops that prevent inflammation on the ocular surface.8, 9
Punctal plugs: These plugs are inserted into the punctum (tear duct) of our eyelids blocking tears from draining off the front of our eyes.
Steroid drops: Steroid drops can be used short term to reduce ocular surface inflammation, but can have lasting side effects.6
Dry eye disease, when chronic and severe, can be debilitating to some patients. Treating dry eye requires consistent compliance with treatment regimens, including recommended follow-ups with an eye care practitioner to determine progress and symptom improvement. Co-management with primary care physicians and specialists to determine if a patient’s dry eye is caused by a systemic disease or by a habitual medication is essential is tackling the signs and symptoms.