Introduction:
The orbit is a bony case that houses the eyeball and its associated muscles, blood vessels, and nerves. Many diseases can affect the orbital contents causing symptoms like swelling, pain, loss of vision, etc. Most of these diseases are space-occupying, and they cause the eyeballs to bulge out. The disorders range from simple inflammation to orbital neoplasms. Most of these diseases occur without a specific underlying cause, and thus the term nonspecific orbital inflammation is used to address these lesions.
What Is Orbital Inflammation?
Orbital inflammation is known by various names:
1. Nonspecific orbital inflammation (NSOI).
2. Orbital inflammatory pseudotumor.
3. Idiopathic orbital inflammation (IOI).
4. Orbital inflammatory syndrome.
These names describe the conditions that commonly cause a painful mass that can be specific to a particular site or diffuse. Orbital inflammation, irrespective of the underlying cause, damages the surrounding tissues. This happens by leakage of the inflammatory cells and fluid inside the blood vessels into the spaces outside the cell.
What Are the Types of Orbital Inflammation?
A. Localized:
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Inflammation can affect the muscles of the eyeballs, causing a condition called orbital myositis.
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The lacrimal gland (tear-producing glands) can get inflamed (dacryoadenitis).
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Inflammation of the sclera (the white layer of the eye covering the eyeballs) and uvea (the layer of the eye below the sclera).
B. Diffuse:
- Diffuse nonspecific orbital inflammation includes the fatty tissues of the orbit.
How Commonly Does Orbital Inflammation Occur?
The condition can affect adults as well as children. Nonspecific orbital inflammation accounts for up to 8 % to 10 % of all orbital disorders.
What Causes Orbital Inflammation?
As mentioned above, the nonspecific orbital inflammation has no apparent underlying condition. Therefore, the diagnosis is made after excluding other conditions discussed below:
1. Infections - Several infections from bacteria and viruses can cause inflammation of the orbital content.
2. Ruptured Cysts - A dermoid cyst is a sac-like mass that can develop in the eye. If the cyst ruptures, it causes similar symptoms due to inflammation.
3. Abnormally Placed Lacrimal Gland - It is a rare condition, but it should not be ruled out.
4. Foreign Body Retained Inside - Retained foreign bodies cause inflammation and bulging of the eyeballs.
5. Sarcoidosis - It is an autoimmune condition that causes inflammation of the eye and can affect any part of the eye.
6. Grave’s Disease- Another autoimmune condition that affects the thyroid gland and produces symptoms of orbital inflammation is Grave's disease.
7. Systemic Vasculitis - A generalized condition that causes inflammation of the blood vessels. Vasculitis of the eye can present symptoms similar to nonspecific orbital inflammation.
8. Systemic Lupus Erythematosus (SLE) - SLE is an autoimmune condition that can cause inflammation of any part of the eye.
What Are the Signs and Symptoms of Orbital Inflammation?
Non-specific orbital inflammation shows a wide range of clinical presentations depending on the affected region.
1. The eyeballs and their covering (conjunctiva), eyelids, nerves, and muscles are affected.
2. Pain in and around the eyes is a common complaint.
3. Patients also complain of swelling or feeling the presence of a mass in the eye.
4. Limited mobility of the eye.
5. Bulging of eyeballs (exophthalmos).
6. Retinal detachment can also be seen.
7. Conjunctival chemosis (a type of eye inflammation) is a common sign.
8. In extreme cases, there can be changes in the vision.
9. Inflammation of the muscles of the eyeball can lead to pain, double vision, eyelid swelling, and restricted mobility.
10. Some patients also complain of dry eyes if lacrimal glands are involved.
11. Sclerosing orbital inflammation is a serious condition with a severe, chronic, progressive disease causing bulging of the eye, swelling, pain, and restricted movement.
How Is Orbital Inflammation Diagnosed?
The diagnosis is confirmed after ruling out other possible conditions. The diagnostic tools involve:
A. High-resolution CT (computed tomography) and MRI (magnetic resonance imaging) scans- are preferred because the orbital structures, including the adjacent sinuses, can be clearly visualized.
The findings include one or more of the following:
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Enlarged lacrimal glands with blurred margins but well-preserved shape.
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Enlarged muscles of the eyeball with blurred margins and inflammatory infiltration around.
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Tissues surrounding the optic nerve (the nerve that transmits impulses to the brain from the retina at the back of the eye) demonstrate a "tramline" sign (parallel thickening and enhancement around the optic nerve).
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The sclera and uvea demonstrate thickening.
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The orbital fat also shows inflammatory changes.
B. Biopsy- the role of a biopsy in the diagnosis is still under debate. It is only considered in the case of progressive disease, lack of response to steroid treatment, and persistent abnormalities. In addition, a well-defined apparent mass may not be distinct for a biopsy approach.
What Is the Treatment for Orbital Inflammation?
A. Observation -
For mild cases, observation is sufficient as the symptoms resolve on their own. However, if there is no resolution or the symptoms worsen, a pharmacological approach is considered.
B. NSAIDs (Non-steroidal Anti-inflammatory Drugs) -
Analgesics and anti-inflammatory medications like Ibuprofen can be used in mild cases. The symptoms usually resolve after 3 weeks to 4 weeks of therapy. If the NSAIDs cause gastritis as a side effect, then Omeprazole or Esomeprazole is prescribed.
C. Corticosteroids -
NSAIDs can be given in combination with corticosteroids. These are drugs that reduce inflammation by interfering with the action of inflammatory cells. Patients show drastic improvement after corticosteroid therapy.
D. Radiation Therapy -
It is given as adjuvant therapy for patients who do not respond to other treatment modalities.
Conclusion:
Orbital inflammation is a condition that commonly causes a painful mass and orbital inflammation irrespective of the underlying and damages the surrounding tissues. This happens by leakage of the inflammatory cells and fluid inside the blood vessels into the spaces outside the cell. Orbital inflammation can be localized or diffuse. The symptoms include pain, restricted movement of the eyeballs, swelling, bulging or protruding eyeballs, visual disturbances, etc. The diagnosis is made after ruling out other conditions. Treatment involves observation, NSAIDs, corticosteroids, and radiation therapy.
