Scleritis

Scleritis refers to inflammation of the sclera. It has a wide range of causes.

Epidemiology

It can affect any age group but usually those between ages 30 and 50 years. There is a recognized increased female predilection (F:M of ~2:1).

Pathology

Information on the pathogenesis of scleritis is limited due to a lack of published data. However, a predominant role for T cells in the inflammatory process has been postulated ¹.

Associations

Scleritis can be associated with several systemic infections as well as non-infective systemic conditions which include ¹:

• rheumatoid arthritis: 18-33%
• systemic vasculitides: 7-19%
  • granulomatosis with polyangiitis: most common
• systemic lupus erythematosus: 4-7%
• inflammatory bowel disease: 4-7%
• relapsing polychondritis: 3%
• Behçet disease: rare ⁶
• sarcoidosis: rare
• cryoglobulinaemia: rare
• hypocomplementaemic urticarial vasculitis: rare
• Cogan syndrome
• herpes zoster infection: most commonly associated infection

Classification

One classification system is the Watson and Hayreh system which divides scleritis into anterior and posterior forms based upon the anatomic distribution.

• anterior scleritis
  • diffuse anterior scleritis
  • nodular anterior scleritis
  • necrotizing anterior scleritis with inflammation
  • scleromalacia perforans (necrotizing anterior scleritis without inflammation)
• posterior scleritis

Radiographic features

Ultrasound

Ocular ultrasound may play a role in the diagnosis and management of posterior scleritis.

CT/MRI

CT and MRI imaging may also play a role in the diagnosis of scleritis especially during the active phase of the disease. Radiological findings include:⁷

• scleral thickening
• scleral enhancement
• focal periscleral cellulitis

See also

• orbital pathology