How Your Eye Doctor Can Tell If You Have Dry Eyes

As discussed in an earlier post, one of the most common symptoms of dry eye syndrome is tearing. Even with an explanation of how this occurs, many are unconvinced. How do you know that your doctor isn’t just telling you this to give you pause while he slips out of the exam room and on to his next patient. “Ah, the old dry eye ruse:” tell the patient that having too much tear is really related to having too little tear and disappear through the door while the unsuspecting patient is mulling this over.

Well, as much as the demands of modern medicine do limit that amount of time doctors can spend with their patients (and, BTW, this really is not in the doctors control – topic for another post), the dry eye explanation is not a ruse. Dry eye syndrome is something that can often be objectively diagnosed at the slit lamp (aka biomicroscope) in the eye doctor’s office. Following is a description of how an ophthalmologist would typically diagnose dry eye syndrome.

Assess Symptoms

As with most medical disorders, the diagnosis of dry eye syndrome is 80% listening to the patient. Following are the things I listen for:

What are the symptoms?

Tearing
Ocular irritation
Foreign Body Sensation (a sense that something is in the eye)
Red eye
Tired eyes
Flucturating vision with certain activities

When do the symptoms occur?

First thing in the morning
Later in the day
After extended periods of concentration
With reading
With computer use
With TV use

What medications are currently being used?

Blood pressure medications
Diuretics
Hormone replacement therapy
Allergy medications

Examine The Eye

Even with the best listening, the diagnosis must be confirmed by examining the eye. Following are the things I look for:

A decreased tear lake (a thin tear film over the cornea)
A decreased Tear Breakup Time (the tear film is not stable)
An irregular corneal surface
Dry patches on the corneal surface

Test The Tear Film

Sometimes special testing is required to diagnose dry eye syndrome. Following are some common tests for dry eye syndrome:

Schirmer’s testing: evaluates how much tear is produced in five minutes
A decreased Tear Breakup Time (the tear film is not stable)
Lissamine Green staining: reveals devitalized corneal surface cells
Rose Bengal staining: also reveals devitalized corneal surface cells
Lactoferrin level test: a low level indicates dry eyes

Not all of the above examination or testing methods are necessary to diagnose dry eye syndrome. However, some combination of the above is used to provide a more objective assessment of the presence or absence of dry eye.