Dr Ben Wild
Overview |
Dry eyes represent a breakdown of the complex interplay between tear volume (amount of tears), tear film stability (how long the tears last before evaporating), inflammation, and eyelid function.
Frontal view of a healthy eye.
Briefly, the lacrimal gland and 2 other accessory glands produce the watery (aqueous) portion of the tears responsible for oxygen transmission, removal of debris, antimicrobial activity, and optimal optical performance. The meibomian glands, located along the edges of the eyelids, produce the oil (lipid) portion of the tears responsible for protecting the aqueous portion from evaporation. Lastly, there is a mucous portion, found attached to the cornea and conjunctiva, that helps in spreading the tears for lubrication. For these tears to function properly, the eyelids must also be free of inflammation and provide frequent and full blinks.
Dry eyes can be broken down into 2 main causes; aqueous deficient and evaporative. Aqueous deficiency can stem from old age, Sjogren’s syndrome, inflammation, scarring of the lacrimal gland, sensory loss (long history of contact lens wear, diabetes, laser surgery, etc.), nerve paralysis from botox or facial palsies, vitamin A deficiency, and certain medications. Evaporative dry eye occurs from meibomian gland dysfunction, incomplete lid closure or improper ocular anatomy, various dermatitis conditions (skin inflammation), low blink rate, certain medications, vitamin A deficiency, chronic inflammation, and more. Either of these causes can be made worse by environmental factors like allergens, smoke, humidity, hormones, and age.
Front view of a severely dry eye.
Signs and Symptoms |
Signs
Red eyes, stringy discharge, red eyelids, low tear volume, filaments.
Symptoms
Ocular grittiness and burning, itchy eyelids, fluctuating vision throughout the day or with each blink, watery eyes.
Causes and Risk Factors |
Causes
Patient factors | Age, Asian ethnicity, contact lens wear, laser eye surgery, female, MGD, menopause, pregnancy, certain makeups, poor sleep. |
Health conditions | Allergies, low testosterone, autoimmune diseases (Sjogren’s, rheumatoid arthritis, sarcoidosis, thyroid dysfunction, etc.), viral infection, rosacea/other other dermatitis, diabetes, sleep apnea (air from the CPAP machine). |
Lifestyle / Environment | Air flow (sleeping with ceiling fan, vents from cars, etc.), alcohol, lack of sleep, dehydration, smoking, low omega 3s, pollution, low humidity, lack of blinking due to concentrated tasks like computer, reading, driving, etc. |
Medications | Analgesics, anesthesia, acne, allergy/decongestants, anxiety/depression, arrhythmic, high blood pressure, botox, anti-psychotics, Parkinson’s, cancer, hormone replacement therapy, multivitamins, any eye drop with preservatives, sedatives, oral contraceptives. |
Eye conditions | Pterygium, pinguecula, EBMD, Salzmann, dacryadenitis, MGD, blepharitis, conjunctivitis, floppy eyelid syndrome, conjunctovochalasis, lagophthalmos and more. |
Prevention and Treatment |
Prevention
Address the health conditions and lifestyle / environmental factors listed above. Supplement your tears with artificial tears if you are taking a medication or have an eye condition listed above. Maintain proper lid hygiene, maintain a diet rich in omega 3s, avoid smoking, avoid dehydration, take 20 second breaks every 20 minutes to blink when reading or on the computer.
Treatments
Level 1 | Blinking exercises (google Donal Korb blink training), humidifiers, avoid high air flow (fans), avoid airborne pollutants and allergens, artificial tears, avoid laser eye surgery, review medications, decrease temperature, warm compresses with Bruder mask for 10 minutes followed by lid massages (massage top lid in a downwards direction and bottom lid in an upwards direction), eyelid hygiene (wipes), omega 3 supplementation, quit smoking, decrease contact lens wear time or switch to daily disposables. |
Level 2 | Preservative free artificial tears, gel drops, ointments, non-steroid anti-inflammatory drops, steroid drops, cyclosporin or lifitegrast drops, tetracycline pills, punctal plugs (stop tears from leaving the eye), secretagogue pills, moisture chamber goggles. |
Level 3 | Serum drops (from blood), scleral contact lenses (hard plastic lenses filled with saline), permanent punctal occlusion. |
Level 4 | Salivary gland transplant, tarsorrhaphy (sow eyelids partially shut). |
Prognosis |
Dry eye, in most cases, is very manageable. With that being said, depending on the cause, there may be no cure. Because there is a wide spectrum of symptoms and severities associated with dry eye, it is hard to elucidate a single prognosis. In most cases, dry eye will be only a minor inconvenience of comfort but in severe cases, can cause a lifetime of extreme discomfort, vision fluctuations, and ocular surface diseases.
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