History
Scleritis is subacute; with a more gradual onset than in episcleritis. [26] Scleritis generally persists from months to years, whereas episcleritis usually resolves within weeks. Both eyes are affected in slightly more than one half of cases.
Severe, constant, deep, boring, or pulsating pain is noted. Pain worsens with movement of the eye and is worse at night and may awaken the patient. Pain may be referred to the eyebrow, temple, or jaw. Occasionally, the configuration of the pain pattern corresponds to the course of the trigeminal nerve.
Erythema of the eye is a defining symptom with anterior scleritis. Other signs and symptoms include lacrimation and photophobia. Discharge is ordinarily not part of the clinical picture of scleritis. Less common manifestations include nausea/vomiting and headache
Prior history may include underlying systemic disease [12] , trauma, ocular surgery, glaucoma, exposure to irritants/chemicals, previous use of eye drops and medications. Uncommonly, patients may report similar previous episodes.
Physical Examination
As with any eye complaint (except chemical injury), begin with vision testing. Visual acuity may be normal or decreased with all forms of scleritis. Visual impairment is most pronounced with posterior scleritis. [27]
Additionally, a complete physical examination, particularly of the skin, joints, heart, and lungs, may be obligatory when an underlying complicating illness is suspected.
For the eye examination, ensure satisfactory lighting. Inspect for breadth and degree of injection, as well as the presence of a bluish hue signifying attenuation of the sclera. Prominent findings may include photophobia, tearing without discharge, tenderness of the eye, and purplish red, edematous, engorged blood vessels. Deeper sclera blood vessels appear darker, follow a radial pattern, and do not move when manipulated with a cotton swab. Administration of topical phenylephrine 2.5-10% causes blanching of the more superficial episcleral vessels but does not change the engorgement of deeper sclera vessels and can help differentiate between scleritis and episcleritis.
Infectious scleritis should be suspected in patients with a history of eye trauma or surgery. Eye examination findings in infectious cases include mucopurulent exudate, scleral ulcers, or scleral abscesses. [28]
Perform a slit lamp/biomicroscopic examination to judge the depth and breadth of involvement. Determine whether there is diffuse or segmental involvement. Widespread injection of the conjunctival and deep scleral vessels is characteristic of diffuse anterior scleritis. Localized elevation of the sclera is representative of nodular anterior scleritis.
Nodules in anterior scleritis are immobile, differing from the non-mobile nodules that can be seen in episcleritis. Scleral thinning is suggested when the choroid pigment becomes a blue-violet hue best seen in natural lighting. Global perforation typically results in an abnormal shape of the pupil and/or uveal or vitreous prolapse. Use of a red-free filter (green light) helps identify avascular areas of the sclera. Corneal changes are present in up to 50% of cases. Examination of the eyelids for possible blepharitis or conjunctivitis should be performed.
Assess the anterior chamber for possible narrowing, hyphema, or hypopyon. Angle narrowing can be seen in acute angle-closure glaucoma. Hyphema can be seen with trauma and/or bleeding disorders. Hypopyon may be seen in uveitis/iritis.
External findings associated with posterior scleritis include restriction of eye movements, sensitivity to palpation, and proptosis. Dilation of the fundus may be necessary to identify posterior scleritis. Posterior scleritis may simulate amelanotic choroidal melanoma. Funduscopic examination of the patient with posterior scleritis may also reveal papilledema, choroidal folds, and retinal hemorrhage or detachment. [24]
