Dry eye disease (DED) is an intricate condition. So many internal and external factors contribute to DED, many of which patients are unaware. Also, all dry eye patients are different — there is no “one-size-fits-all” treatment. Knowing the available DED diagnostic tools, and taking a focused history, can help to identify a custom treatment solution for your patients and bring quicker comfort that improves their quality of life.
To help your doctor arrive at the right solution, become a super sleuth by using all your diagnostic tools.
Using a questionnaire, such as SPEED or OSDI, as a routine part of the evaluation can help the practitioner in quickly assessing the severity of the problem, as well as guiding them towards an appropriate treatment plan. It also serves as a guide to track progress as the patient returns for subsequent visits.
One of the best and simplest tools to rely on is a detailed patient history, which should include the following:
- Symptoms. This provides an excellent baseline as well as clues to what is going on, why it is going on, and specific things the doctor should be looking for during visual examination.
- What aggravates symptoms? This provides information on specific extrinsic factors that affect the patient and ideas for potential solutions on an external level.
- Family history. A vital portion of the exam because of the possible genetic predisposition to certain diseases.
- Medical history and medications. This covers intrinsic factors of medical conditions that have associations with dry eye (such as Sjögrens and rheumatoid arthritis) and medications for conditions that might be contributing to the problem (such as antihistamines or antidepressants). Also, many patients are on medications for conditions that have no association with dry eye, but the medications contribute to dry eye (such as antihypertensive medications). Changing a medication that treats their condition could help their dry eye problem.
- Treatment history. What have they tried to help with their dry eye? This becomes incredibly helpful when the physician is formulating a treatment plan. It covers what has worked and what has not, and provides information on patient compliance or what they may be doing that contributes to the problem (such as contact lens wear or sitting under a fan).
- Skincare and makeup. This can be a huge component. We live in an age of aesthetics and anti-aging, and not all the things we apply to our skin are ocular friendly or dry-eye safe, regardless of their cost or effectiveness. Simple adjustments can provide big changes. Are they using soap near the eyes? Eyeliner in the waterline? Waterproof makeup? Even worse, false eyelashes or eyelash extensions? Even Botox can change the blink mechanism and lead to dry eye.
Also, never underestimate the power of visual observation. Watch the patient’s blink pattern. Do they blink fast, slow, hard? Do their lids close completely with each blink? Is there laxity in the lids or heaviness in the midface region that pulls down on their lower lids? Do they have sensitivity to light or blurry vision resolved with blinking?
Under the slit lamp, there are many things to look at, but some are specific for dry eye patients.
- Korb readings. Use a Meibomian Gland Evaluator to gently press against the lower lid margin, and observe meibum secretions. Look for quantity of actively producing glands temporally, medially and nasally. Quality of oil should appear like olive oil; take notes for cloudy oil or thick, toothpaste-like consistency.
- Telangiectasias. Excess of tiny little blood vessels could be an indicator of inflammatory conditions, such as rosacea or ocular rosacea, and provide excellent target for treatments, such as Intense Pulsed Light (IPL).
- Demodex. Nasty little mites that live in or near hair follicles, and particularly enjoy the lashline and leave behind a toxic environment around the eyes.
- Tear Break Up Time (TBUT). The stability of the tear film is also important to evaluate. Measure TBUT with the tiniest amount of fluorescein (instilled with a fluorescein strip) at the lower lid, and measure the break up of the fluorescein visualized under the slit lamp. (TBUT can also be visualized non-invasively with diagnostics such as Antares by Lumenis).
- Fluorescein and lissamine green staining. Evaluation with staining is performed on every dry eye patient at each visit to evaluate damage and treatment progress.
Tear osmolarity testing
Dry eye symptoms can vary greatly between patients, but one consistent factor in diagnosing DED is tear osmolarity, or the saltiness of the tears. The TearLab Osmolarity System is a simple test that assigns an numerical value to tear osmolarity (milliosmoles/liter, or mOsm/L). This allows you to compare values and gauge progress and effectiveness of treatment.
Using a handheld device with a disposable tip, catch a small amount of tear from the inferior lateral meniscus of the tear film, which is quick and painless for the patient. Place the handpiece into the docking station analyzer, and diagnostic results are almost immediate. Values of 309 mOsm/L and above are indicative of hyperosmolarity, or dry eye; 290-309 mOsm/L suggests borderline or intermittent dry eye; 290 mOsm/L and below is considered healthy and normal. This test has a CPT code and is recognized as a billable test covered by most insurance carriers.
Inflammation is an early detector of ocular surface disease, and there has been a high correlation with dry eye and inflammation. Knowing whether inflammation is present changes the treatment protocol, as some medications or devices are more effective at treating the inflammatory burden.
InflammaDry (Quidel) is an in-office test that detects MMP-9, an inflammatory marker. To administer: use a collection device, dab along the inner lower lid conjunctiva, then place the device in a cartridge with a dipstick in a solution for about 15 seconds. Next, cap the device and set it aside for about 10 minutes. Results greatly resemble a pregnancy test — results are shown with a control line in blue and any inflammatory response line in pink. The amount of inflammation present is subjective to the evaluator’s opinion of the darkness of the pink line.
InflammaDry is covered by most insurance; no other devices are needed to evaluate the results.
Shirmer’s testing or Phenol thread testing
Both of these tests indicate the quantity of tears produced in a specified time window.
Shirmer’s testing requires numbing the eye, drying excess moisture around the site of application, and placing a special paper strip inside the lid. Patient rests with their eyes closed for 5 minutes, and the paper strip is gently removed. Moisture travels up the strip and values are shown in millimeters, >10 is considered normal, 5-9 is dry eye, where <5 is severe dry eye.
Phenol thread testing is similar, but does not require numbing drops, and only takes 15 seconds for results.
Meibomian Gland Dysfunction (MGD) is diagnosed with special imaging technology called meibography. Using a device, such as LipiScan (Johnson & Johnson), pictures of the oil producing meibomian glands can be acquired for a closer visual look, and help address the degree of MGD.
Tests are available that can help diagnose the allergic component contributing to dry eye. Another method is to instill an ophthalmic drop for allergies in one eye. After three minutes, ask the patient how that eye feels.
DED has so many different possible causes. Patients are experiencing different symptoms and varying levels of discomfort, from mild to severely debilitating, but you have the opportunity to be part of a team to help your doctor determine the cause and start effective treatment plans on your patients.
There is no greater satisfaction than your patients reporting back to you that they can read again or drive again because treatment is working and allowing them to have normal to near normal function of their eyes.
Happy sleuthing to you all! OP