Dry eye is a common condition where the eyes do not produce enough tears, or the tears produced are of poor quality and evaporate too quickly. This imbalance can lead to uncomfortable symptoms and affect vision. This article details common dry eye symptoms and the diagnostic procedures used by eye care professionals.
Recognizing the Signs
Individuals experiencing dry eyes often report a distinct gritty or sandy sensation, as though something is persistently in the eye. This feeling can be accompanied by a burning or stinging discomfort that intensifies throughout the day. Redness of the eyes is another common visual sign, often resulting from irritation and inflammation of the ocular surface.
Blurred or fluctuating vision, especially after engaging in activities requiring sustained visual focus like reading or computer use, can also indicate dry eyes. Sensitivity to light, known as photophobia, may cause discomfort in bright environments. Paradoxically, some individuals with dry eyes may experience excessively watery eyes, as the eye attempts to compensate for dryness or irritation by producing reflex tears.
Discomfort when wearing contact lenses is a frequent symptom, as dry eyes can reduce the lubrication needed for comfortable lens wear. These symptoms tend to worsen in dry or windy environments, or after prolonged periods without blinking, such as during extensive screen time. The presence of stringy mucus in or around the eyes can also be an indicator of tear film instability.
Knowing When to Seek Professional Help
If symptoms like persistent dryness, burning, or irritation do not improve with over-the-counter remedies, a professional evaluation is advisable. Occasional dryness might be managed with artificial tears, but chronic discomfort warrants further investigation.
Symptoms that begin to interfere with daily activities, such as reading, driving, or working on a computer, also signal a need for professional attention. Experiencing consistent eye pain or if the symptoms worsen over time, rather than improving, are reasons to schedule an appointment. Early diagnosis and intervention can prevent potential complications, including increased risk of eye infections or damage to the eye’s surface.
Professional Diagnostic Procedures
A thorough diagnosis of dry eyes typically begins with a detailed discussion of the patient’s symptoms and medical history. The eye care professional will inquire about the nature, duration, and frequency of symptoms, as well as any contributing environmental factors or medications.
Following the history, a comprehensive eye examination is performed using a slit lamp to examine the eye’s surface, tear film, and eyelids. Specific tests are then conducted to assess tear quality and quantity. The Tear Break-Up Time (TBUT) test measures how long tears remain stable on the eye’s surface before evaporating. A small amount of fluorescein dye is applied to the eye, and the time until the first dry spot appears is observed under a blue light; a time shorter than 10 seconds generally indicates tear film instability.
The Schirmer’s test evaluates tear production, involving the placement of a thin strip of filter paper inside the lower eyelid for five minutes. The amount of moisture absorbed by the paper, measured in millimeters, indicates the volume of tears produced, with less than 10 mm often suggesting insufficient tear production. Ocular surface staining, using dyes like fluorescein or lissamine green, reveals areas of damage on the cornea or conjunctiva. Fluorescein highlights corneal abrasions and epithelial erosions, while lissamine green stains devitalized cells and mucus on the conjunctiva, revealing surface irregularities.
Meibography is an imaging technique used to visualize the meibomian glands located within the eyelids. These glands produce the oily layer of the tear film, which prevents rapid tear evaporation. This non-invasive procedure captures images of the glands, allowing the professional to assess their structure and identify any dysfunction, such as blockages or atrophy, contributing to evaporative dry eye.