Inflammatory process of the sclera of varying intensity with the most severe form, necrotizing scleritis, with potential destruction of all structural and cellular components.
Many cases presumed to be autoimmune in etiology.
Sclera infiltrated with inflammatory cells, especially macrophages, and T lymphocytes.
Less common causes are traumatic or infectious.
Among rheumatologic disorders the most common associated with scleritis are rheumatoid arthritis, and ANCA associated vasculitides.
May be associated with relapsing polychondritis, polyarteritis nodosa, systemic lupus, Behcet’s disease, and hypocomplementemic urticarial vasculitis.
Can be caused by bisphosphonates.
Biopsy of the sclera is rarely perform because of the potential to perforate the globe.
Scleritis can be a localized manifestation of a systemic vasculitis.
Scleritis is often divided into types, posterior scleritis, which is the least common type in the most difficult to diagnose because the posterior sclera can be inflamed without producing any redness.
Posterior scleritis is it is diagnosed by ultrasound images of the eye.