Dry Eye Disease

Dry eye disease (DED) is a chronic, multifactorial condition defined by tear film instability and hyperosmolarity. It encompasses both aqueous-deficient and evaporative subtypes — with evaporative dry eye, driven largely by meibomian gland dysfunction, representing the predominant form in clinical practice. Symptoms range from mild intermittent irritation to debilitating ocular surface pain, and the condition frequently coexists with other ocular surface disorders.

Prevalence estimates range from 5–50% depending on diagnostic criteria and population studied. DED disproportionately affects women, older adults, contact lens wearers, and individuals with systemic inflammatory conditions. It is among the most common reasons patients present to eye care providers.

The central mechanism of DED is a vicious cycle initiated by tear film instability and hyperosmolarity. Hyperosmolarity activates inflammatory cascades on the ocular surface, including upregulation of pro-inflammatory cytokines (IL-1β, TNF-α, MMP-9) and T-cell–mediated immune responses. This inflammation damages goblet cells and the glycocalyx, further destabilizing the tear film and perpetuating the cycle.

Evaporative DED is driven primarily by meibomian gland dysfunction (MGD), which reduces the lipid layer of the tear film and accelerates evaporation. Aqueous-deficient DED results from lacrimal gland insufficiency, as seen in Sjögren's syndrome and other autoimmune conditions.

Neurosensory abnormalities — including peripheral sensitization and central sensitization — contribute to symptom severity and may persist even after objective signs improve. This disconnect between signs and symptoms is a defining clinical challenge in DED management.

Patients commonly report dryness, burning, foreign body sensation, fluctuating vision, and paradoxical tearing. Symptoms often worsen with prolonged screen use, reading, low-humidity environments, and contact lens wear. Clinical signs include reduced tear meniscus height, rapid tear breakup time (TBUT), corneal and conjunctival staining with vital dyes, and meibomian gland dropout on meibography. Lid margin irregularity, telangiectasia, and meibum quality changes are frequently observed in the evaporative subtype.

Management is stepwise and guided by disease severity. Mild DED is typically addressed with preservative-free artificial tears, lid hygiene, and environmental modifications (humidification, screen breaks, blink exercises). Omega-3 supplementation and warm compresses with lid massage address the meibomian gland component.

Moderate DED warrants anti-inflammatory therapy. Topical cyclosporine (Restasis®, Cequa®, Vevye®) and lifitegrast (Xiidra®) are the primary FDA-approved immunomodulatory options. Short-course topical corticosteroids (Eysuvis®, Lotemax SM®) serve as rescue and bridge therapy. Punctal occlusion reduces tear drainage and is appropriate when aqueous deficiency is a significant contributor.

Severe or refractory DED may require autologous serum tears, scleral contact lenses, amniotic membrane therapy, or systemic anti-inflammatory management in collaboration with rheumatology. Neurostimulation (Tyrvaya®) targets the nasolacrimal reflex arc to increase basal tear production.

Follow-up intervals depend on disease severity and treatment stage. Patients initiating immunomodulatory therapy should be seen at 4–8 weeks to assess tolerance and early response, with reassessment at 3–6 months. Meibography and vital dye staining provide objective benchmarks. Symptom questionnaires at each visit allow standardized tracking of patient-reported outcomes.