Episcleritis and scleritis
The sclera is the white part of the eye. When it becomes inflamed, swollen, red, tender, or painful, it is called episcleritis or scleritis, depending on the depth of the inflammation. If the inflammation is superficial, it is called episcleritis. If it is deep, it is called scleritis. Patients with scleritis sometimes have an underlying condition such as rheumatoid arthritis or another autoimmune disease. This is much less common in cases of episcleritis. When no cause is found, it is called idiopathic inflammation. Treatment for episcleritis and scleritis relies on steroidal and non-steroidal anti-inflammatory drugs.
What are episcleritis and scleritis?
Episcleritis corresponds to an inflammation of the superficial tissues of the sclera.
Scleritis is an inflammation of the deeper layers of the sclera. It can affect two locations on the eye:
Anterior scleritis – Inflammation occurs at the front of the eye; redness is visible to the patient.
Posterior scleritis – The lesion is located at the back of the eye. It is not red, but the patient experiences increased pain with eye movement. The ophthalmologist makes the diagnosis through fundus examination or ultrasound.
Anterior scleritis is more common than posterior scleritis. There are three types of anterior scleritis:
Sectorial or diffuse plane scleritis – This is the most common form. The eye is red, either entirely or partially.
Nodular scleritis – The sclera presents one or more painful nodules (bumps).
Necrotizing scleritis – The sclera becomes hollow. This is the most serious form because the globe risks perforating.
Posterior scleritis is the rarest form. People with this type of scleritis may experience pain and tenderness behind the eyeball. This form can cause problems leading to exudative retinal detachment and angle-closure glaucoma.
Some patients present with only one type of scleritis, but others may present with combined forms: anterior and posterior, or diffuse and necrotizing.
Causes
Episcleritis is often benign and idiopathic, meaning it has no identifiable cause. Scleritis is often linked to an autoimmune disease. Idiopathic forms are much rarer.
Scleritis (and some episcleritis) can be caused by:
Arthritis – Inflammation, swelling or stiffness of the joints of autoimmune origin.
Lupus or another connective tissue disease.
An eye infection.
Inflammatory bowel disease (IBD) – Such as Crohn's disease.
Sjögren's syndrome – which causes significant dry eye and inflammation.
Granulomatoses – Tuberculosis or sarcoidosis in the first place.
Scleroderma.
Trauma – whether surgical or accidental – can lead to inflammation that is difficult to control.
Symptoms
The symptoms of episcleritis and scleritis are similar. However, in the case of scleritis, they will be more intense.
Redness (hyperemia) – Localized or diffuse, slight or marked.
The pain – It can be intense and cause insomnia.
Photophobia – Sensitivity to light
Edema – Swelling of the white part of the eye.
Visual blur
Tearing
Diagnosis
If you experience symptoms of episcleritis or scleritis, you should see an ophthalmologist as soon as possible. Without treatment, scleritis can lead to vision loss.
During your examination, your ophthalmologist:
Will perform a slit-lamp examination of the surface of the eye and the fundus of the eye.
The interview will look for symptoms of extraocular autoimmune, inflammatory or infectious diseases.
He may complete his assessment with an ocular ultrasound, an OCT or an angiography in order to highlight a posterior scleritis.
Your ophthalmologist may collaborate with your general practitioner or a rheumatologist (a doctor who treats certain autoimmune diseases) to establish the underlying cause (etiological assessment). Blood tests and X-rays may be requested.
Treatment
Episcleritis is usually benign and will resolve spontaneously. In cases of significant or persistent pain, anti-inflammatory eye drops may be prescribed to relieve symptoms and reduce their duration.
However, scleritis must be treated as soon as symptoms appear to preserve your vision. Treatment varies depending on the type of scleritis. It may include:
Corticosteroids – Anti-inflammatory drugs derived from steroids, in tablets or drops.
Non-steroidal anti-inflammatory drugs (NSAIDs) – such as aspirin or ibuprofen for pain and inflammation.
Eye drops – NSAIDs, corticosteroids or antibiotics to treat the damage to the surface of the eye.
Immunosuppressants – Medications that regulate your body's immune system's response against the eye. They are reserved for severe cases.
In rare cases, surgery may be necessary to seal necrotizing scleritis that could perforate the eyeball. The operation can help repair the eye and prevent further vision loss.
Evolution
Episcleritis can recur. In cases of regular flare-ups of eye redness, an inflammatory workup may be performed.
When scleritis is caused by another disease, that disease must also be treated to control the symptoms.
Remember that despite treatment, scleritis can recur. It is important to see your ophthalmologist and other doctors regularly to obtain the most effective treatment.
Complications
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Episcleritis can progress to scleritis if left untreated. However, this is an exceptional and almost never serious condition.
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In cases of scleritis, particularly its necrotizing form, the sclera can thin and progress to perforation of the eyeball. Visual impairment is rare in cases of scleritis, but can sometimes be severe.