Dry eye disease
Exam Tips
- Symptoms and signs correlate poorly; severe discomfort can coexist with limited visible signs.
- Red flags needing urgent same-day ophthalmic assessment: sudden painful visual loss, unilateral marked pain/redness, diplopia, corneal opacity/ulcer suspicion, systemic red flags (e. g, fever, weight loss).
- In OSCEs, always inspect lids and blink dynamics (lagophthalmos, infrequent blink, lid margin disease) rather than focusing only on conjunctival redness.
- Differentiate evaporative vs aqueous-deficient patterns because management emphasis differs (lid therapy vs tear conservation/replacement).
- If dry eye is severe, persistent, or associated with dry mouth/arthralgia, screen for Sjogren or connective tissue disease.
- Image recall: tear-film layer schematic and punctate fluorescein staining appearance are high-yield visuals (see standard cornea/external eye chapter figures in ophthalmology texts).
Definition
Dry eye disease (keratoconjunctivitis sicca) is a chronic, multifactorial disorder of the ocular surface in which tear-film homeostasis is disrupted by reduced tear production, excessive evaporation, or both. The resulting tear hyperosmolarity and surface inflammation cause fluctuating ocular discomfort and visual disturbance, with signs that may be mild despite troublesome symptoms.
Pathophysiology
The normal tear film has lipid, aqueous, and mucin components produced mainly by meibomian glands, lacrimal glands, and conjunctival/corneal epithelium. In dry eye disease, either aqueous deficiency (lacrimal hyposecretion) or evaporative loss (usually meibomian gland dysfunction) destabilizes the tear film, increasing osmolarity. Hyperosmolar stress activates inflammatory pathways (including cytokine and matrix metalloproteinase activity), leading to goblet-cell loss, epithelial microdamage, reduced mucin quality, and further tear instability. Neurosensory dysfunction (abnormal corneal nerve signaling) can amplify symptoms and contribute to the classic vicious cycle of instability, inflammation, and surface injury.
Risk Factors
- Increasing age and female sex (especially peri-/post-menopausal state)
- Meibomian gland dysfunction and blepharitis
- Autoimmune disease, especially primary/secondary Sjogren syndrome (e. g, with rheumatoid arthritis or SLE)
- Rosacea
- Thyroid eye disease, lagophthalmos, proptosis, lid malposition
- Reduced blink rate (prolonged screen use, Parkinson disease, Bell palsy)
- Low humidity, air conditioning, central heating, wind, smoke/fume exposure
- Contact lens wear
- Previous ocular surgery (e. g, refractive surgery, cataract surgery)
- Drugs associated with dryness (e. g, anticholinergics, antihistamines, tricyclic antidepressants, antipsychotics, beta-blockers, diuretics, isotretinoin, estrogen-containing therapies)
Clinical Features
Symptoms
- Usually bilateral burning, stinging, gritty or foreign-body sensation
- Intermittent blurred vision that improves after blinking
- Paradoxical watering (reflex tearing)
- Dryness sensation, ocular fatigue, and photophobia
- Contact lens intolerance
- Symptoms often worsen later in the day or with prolonged visual tasks
Signs
- Mild conjunctival injection
- Reduced tear meniscus and unstable tear film
- Rapid tear break-up time
- Punctate corneal/conjunctival epithelial staining (fluorescein/lissamine)
- Lid-margin inflammation or capped meibomian orifices with poor meibum expression
- Incomplete blink or lagophthalmos; visual acuity usually not severely reduced
Investigations
Management
Lifestyle Modifications
- Explain chronic relapsing course; optimize adherence and trigger avoidance
- Environmental modification: humidify air, reduce direct fan/heater airflow, smoke avoidance
- Screen hygiene: regular blink breaks (e. g, 20-20-20 strategy), conscious full blinking
- Warm compresses and lid hygiene for blepharitis/MGD
- Review and reduce contributory medicines where clinically appropriate
- Limit or refit contact lenses during active symptoms
Pharmacological Treatment
Lubricating eye drops (tear substitutes)
- Hypromellose 0.3% eye drops: 1 drop 3-4 times daily or as required
- Carmellose sodium 0.5% eye drops: 1 drop up to 4 times daily (or more frequently if needed)
- Sodium hyaluronate 0.1-0.2% eye drops: 1 drop 2-4 times daily, titrate to symptoms
- Polyvinyl alcohol 1.4% eye drops: 1 drop up to 4 times daily
Use preservative-free preparations if frequent dosing, contact lens wear, or ocular-surface sensitivity; benzalkonium chloride can worsen toxicity with chronic use.
Lubricating gels/ointments (especially nocturnal symptoms)
- Carbomer 0.2% eye gel: 1 drop 2-4 times daily
- White soft paraffin + liquid paraffin eye ointment: apply at night
Warn about transient blurred vision after gel/ointment use; caution with activities requiring clear vision (e. g, driving).
Topical immunomodulator for severe keratitis in dry eye
- Ciclosporin 1 mg/mL eye drops (e. g, Ikervis): 1 drop once nightly
Typically initiated in specialist care for severe disease not controlled by lubricants; common adverse effect is instillation pain/burning; monitor response and tolerability.
Short-course anti-inflammatory rescue (specialist-directed)
- Dexamethasone 0.1% eye drops: short tapered course
- Fluorometholone 0.1% eye drops: short course
Use only with ophthalmology oversight due to risks of raised intraocular pressure, cataract progression, and infection masking/reactivation (e. g, herpetic keratitis).
Surgical / Interventional
- Punctal occlusion (temporary plugs or cautery) for selected aqueous-deficient cases after inflammation is controlled
- Tarsorrhaphy in severe exposure keratopathy/lagophthalmos
- Management of lid malposition (e. g, ectropion/entropion repair) when contributory
Complications
- Reduced quality of life (reading, driving, work, sleep) and reduced productivity
- Psychological comorbidity, including anxiety/depressive symptoms
- Recurrent punctate epithelial erosions
- Corneal scarring, thinning, ulceration, or neovascularization in severe disease
- Secondary infectious keratitis
- Rare corneal perforation and permanent visual loss
- Suboptimal outcomes after cataract/refractive/corneal surgery
Prognosis
Usually chronic with fluctuating severity rather than curable. Most patients improve with trigger control, regular lubrication, and treatment of meibomian/lid disease, but progression risk is higher with advancing age, poor adherence, and systemic inflammatory disease.
Sources & References
🏥BMJ Best Practice(2)
💊BNF Drug References(9)
- Alitretinoin[cautions]
- Carbomers[management.pharmacological]
- Carmellose sodium[management.pharmacological]
- Hydroxypropyl guar with polyethylene glycol and propylene glycol[management.pharmacological]
- Isotretinoin[cautions]
- Liquid paraffin with white soft paraffin and wool alcohols[management.pharmacological]
- Retinol palmitate with white soft paraffin, light liquid paraffin, liquid paraffin and wool fat[management.pharmacological]
- Sodium hyaluronate[management.pharmacological]
- Sodium hyaluronate with trehalose[management.pharmacological]
✅NICE Guidelines(1)
- Dry eye disease[overview]