DRY EYE MANAGEMENT IN A BRIEF
DEFINITION
Dry eye can be defined as a multifactorial disease of the tears and ocular surface which often lead to tear film instability, ocular disturbance and ocular discomfort. Dry eye is accompanied by increased osmolarity of the tear film and inflammation of the ocular surface.
DRY EYE SYMPTOMS
Symptoms of dry eyes and dry eye syndrome include:
-Burning or stinging sensation
-Foreign body sensation or grittiness
-Redness, Itching and aching sensation
-Sensation of dryness, Photophobia
-Blurred vision or fluctuating vision (worsened when using digital devices)
-Heaviness, Fatigue and Sore eyes
-Lacrimation and discharge
-Frequent blinking
-Mattering or caking of the eyelashes (usually worse upon waking)
RISK FACTORS ASSOCIATED WITH DRY EYE SYNDROME
-Computer use and other digital devices.
.-Contact lens wear
.-Aging especially after age 50.
.-Female sex
.-Menopause
.-Indoor environment. Air conditioning, ceiling fans and forced air heating systems
.-Outdoor environment. Arid climates and dry or windy conditions
.-Frequent flying. The extreme dry air in thecabins of airplanes
.-Smoking and alcohol
.-Health conditions-such as diabetes, thyroid-associated diseases, lupus, rheumatoid arthritis, Sarcoidosis, HIV and Sjogren’s syndrome, Acne and gout
.-Pregnancy
.-Medications including antihistamines, antidepressants, antihypertensives, contraceptives etc.
.-Eyelid problems.e.g. lagophthalmos,
.-LASIK and other corneal refractive surgery
.-Vitamin A deficiency
STEP BY STEP APPROACH TO DRY EYE DIAGNOSIS
- Symptom Questionnaires (Case hx)
There are many types of dry eye questionnaires developed to unravel dry eye problems. Some of the notable ones include:
a) OSDI Ocular surface disease index
b) SPEED= Standardized Patient Evaluation of Eye Dryness
c) IDEEL=Impact of Dry Eye on Everyday Life
d) DEQ = Dry Eye Questionnaire
(contact a certified FOM Mentor for details)
2. Functional visual acuity Test
Functional visual acuity (FVA) tests measure acuity during and after sustained eye opening for 10-20 seconds, as a simulation of visual function of daily acts of gazing during real-life daily activities. The decay in visual function during the blink interval is assessed. It is a fast and accurate measure visual acuity in patients with dry eye.
Method of testing for FVA
Direct the patient to fixate on the BVA line at 6M
Ask the patient to blink and then stare at the BVA line for 10-20secs.
The patient should report if BVA line remains clear or gradually becomes blurry.
3. External examinations
The eyelids
Blink rate: The normal blink rate while speaking is about 10 -15 blinks/minute. This significantly reduces to about to 3-5 blinks/minute during reading and computer work. A reduced interval between blinks, from about 6 seconds to 2.6 seconds, and incomplete blinking, are typical of patients with dry eye.
Lid congruity and lid closure
Look out for lid incongruity (e.g., ectropion, entropion) or insufficient lid closure (e.g., facial nerve palsy)
Lid margin: Using the slit lamp, look out for inflammation or any dysfunction of the meibomian glands. Check the eyelashes, eyelid margin, and meibomian gland orifices.
The conjunctiva:
Temporal lid-parallel conjunctival folds (LIPCOFs) in straight gaze are a result of increased friction between the lids and the conjunctiva. They are regarded as an important indicator of dry eye, with a sensitivity of 84.9% and a specificity of up to 90%. They can be simply, quickly, and noninvasively identified using the slit lamp.
- Ocular Surface Staining
This is done using the slit lamp and vital stains.
Method: Instil fluorescein
.-Ask the patient to blink in order to distribute fluorescein
.-Remember, to enhance observation, add the yellow filter or a Wratten #12 yellow filter.
.-Observe area of staining on the comb) epithelium or conjunctiva. Any staining is indication of a problem.
Several indices are available for the assessment of 2 staining, such as the following:
- Tear Film Stability Test (TBUT)
10 seconds is the typical cutoff between normal and abnormal results and has been found to be relatively specific in screening patients for tear film instability.
- Tear meniscus assessment
A regular tear meniscus is typically observed in a healthy eye while a meniscus with a scalloped edge is often associated with a dry eye. A foamy tear film is an indicator of an altered lipid layer in patients with meibomian gland dysfunction.
- Tear meniscus Height Test
Tear prism height test is used to diagnose aqueous tear deficiency (ATD) in dry eye.
If the prism height is reduced, patient might have reduced tear volume. On the other hand, increased height suggests poor tear drainage. The average tear prism height is 0.2mm to 0.4mm at the center and 0.1 mm to 0.2mm at the periphery.
- Tear quantity or reflex flow test
The Schirmer test measures the secretions of the lacrimal gland.
The wetting of the strip is measured after 5 minutes.
Result: Normal value > 15mm
Moderate dryness=>5-<15mm
Values of 5 or less are certainly pathological
DRY EYE MANAGEMENT
Optimal management of dry eye requires careful listening to the patient’s history and symptom. Therefore, it is valuable to conduct as symptom survey (dry eye questionnaire) to help identify and categorize the presence and more importantly the severity of dry eye among patients.
Effective approaches towards management include
a) Avoidance of exacerbating factors
b) Tear stimulation and supplementation
c) Increasing tear retention
d) Eyelid cleansing or hygiene
e) Treatment of eye inflammation
Management techniques include;
1. Warm compresses and eyelid massage.
2. Lipid replacement artificial tears.
3. Dietary supplements/omega-3 fatty acids.
4.Artificial tears or Saline
5. Medications
6.Patient education. Easy-to-understand instructions on treatment plans, ergonomic and hygienic tips.
7. Environmental control
8. Punctal plugs
9. Surgery
10. LipiFlow
11. Contact lens wear
CONCLUSION
Dry eye is one chronic disease that can be frustrating for both patient and practitioner. In our ‘quick fix’ society, this is one disease process that does not play by those rules. Practitioners therefore must brace up for the challenge.