Presentation
One week history of painful and tender right eye globe, associated with redness, blurred vision and limited right eye motion. No comorbidities or history of surgery or trauma.
Patient Data
Uniform thickening and enhancement of the posterior sclera of the right eye globe, associated with moderate enhancement of the retrobulbar fat with minimal circumferential enhancement of the right optic nerve sheath. Findings are suggestive of right-sided posterior scleritis with minimal surrounding changes of focal cellulitis and optic perineuritis.
No choroidal effusions or signs of uveitis.
No intraconal or extraconal collections.
The left orbit is unremarkable.
Symmetrical size and pattern of enhancement of both lacrimal glands.
White arrows pointing to a thickened enhancing posterior sclera with minimal enhancement of the retrobulbar fat.
Case Discussion
Scleritis is a rare, usually underdiagnosed disease, which can significantly compromise a patient's vision if left untreated. The most common cause of this entity is a non-infectious inflammatory process that can be either idiopathic or secondary to an underlying systemic disease, most commonly rheumatoid arthritis or granulomatosis with polyangiitis.
Anterior scleritis is more common and easily diagnosed clinically. Posterior scleritis, constituting 2-12% of cases, is more difficult to diagnose clinically.
MR imaging is the most useful and accurate modality used to diagnose this condition. The most common imaging finding is scleral enhancement and thickening. Other imaging findings include focal cellulitis and optic perineuritis secondary to the involvement of the adjacent optic nerve sheath.
Patients usually present with orbital pain, which is the most common presenting clinical feature. Limited eye motion, headaches, eye redness and blurred vision may also be present.
In diffuse scleritis, the differential diagnosis may include posterior uveitis, lymphoma or diffuse melanoma.