| Definition | Inflammation of the sclera, the white outer coating of the eye | Inflammation of the episclera, the thin layer of tissue covering the sclera |
| Cause | Often associated with systemic autoimmune diseases (e.g., rheumatoid arthritis, lupus) | Usually idiopathic; can be associated with mild systemic conditions (e.g., dry eye syndrome) |
| Severity | Generally more severe and painful | Usually mild and less painful |
| Onset | Gradual | Acute |
| Symptoms | Severe eye pain (can radiate to face), redness, vision changes, photophobia, tearing | Mild to moderate eye discomfort, redness, tearing, possible foreign body sensation |
| Redness Location | Diffuse or localized deep red or purple color | Sectoral or diffuse redness, bright red in color |
| Associated Symptoms | May have systemic symptoms such as joint pain, weight loss, or fever | Rarely associated with systemic symptoms |
| Visual Impact | Potentially vision-threatening if untreated | Usually does not affect vision |
| Diagnosis | Requires thorough examination, possibly imaging (e.g., ultrasound, MRI) and blood tests | Clinical examination often sufficient |
| Treatment | – Systemic corticosteroids or immunosuppressive agents | – Topical corticosteroids or NSAIDs |
| – NSAIDs for pain management | – Artificial tears for symptomatic relief |
| – Treat underlying systemic disease | – Resolves spontaneously in 1-2 weeks |
| – Referral to a specialist (e.g., rheumatologist, ophthalmologist) | |
| Complications | – Potential for scleral thinning, perforation, vision loss | – Rarely any complications |
| – May recur if underlying systemic condition is not managed | |
