Orbital inflammation can be classified into specific and nonspecific inflammation. Specific inflammation is caused by identifiable pathogens, such as bacteria or fungi, resulting in conditions like orbital cellulitis. Nonspecific inflammation refers to orbital inflammatory changes or syndromes with unknown etiology, including idiopathic orbital inflammation, painful ophthalmoplegia, sarcoidosis, Wegener’s granulomatosis, Kimura’s disease, nodular arteritis, temporal arteritis, and others.
Orbital Cellulitis:
Orbital cellulitis is an acute inflammation of the orbital soft tissues caused by pathogens. It falls under specific orbital inflammation and can develop rapidly. Severe cases may even be life-threatening when the infection spreads to the sinuses.
Cause:
Orbital cellulitis is more common in children and often results from the spread of infection in the tissues around the orbit. It typically originates from infections in the nasal sinuses or the facial and jaw areas. The most common pathogens responsible for this condition include Staphylococcus aureus, Streptococcus pyogenes, with Hemophilus influenzae being more prevalent in children. Orbital cellulitis can also be triggered by the presence of foreign objects in the orbit after eye trauma or the rupture of intraorbital cysts. In some cases, systemic infections at distant sites can lead to the development of orbital cellulitis through hematogenous spread(sources from therapeutique-dermatologique.org).
Clinical Presentation:
Orbital cellulitis can be classified into preseptal cellulitis and postseptal cellulitis, with the latter also referred to as deep orbital cellulitis. In clinical practice, it can be challenging to strictly differentiate between them, and they may often overlap or progress into each other.
Preseptal cellulitis primarily presents with eyelid redness, swelling, and relatively mild pain. Pupil size and visual acuity are typically unaffected, and eye movement is often normal.
Postseptal cellulitis, also known as deep orbital cellulitis, presents with severe clinical symptoms. In the early stages of the disease, the presence of a significant number of inflammatory cells and tissue edema within the orbit results in the following manifestations:
Protrusion of the eyeball
Severe eyelid swelling
Conjunctival congestion
In severe cases, the conjunctiva may extend beyond the eyelid margins
Impaired eye movement, and it may become fixed
Incomplete eyelid closure, leading to exposure keratitis or corneal ulcers
As the inflammation progresses, increased orbital pressure and the toxic effects of the infection may lead to the following symptoms:
Reduced pupillary response to light
Decreased visual acuity, and potential vision loss
Retinal vein dilation, retinal edema, and exudation seen on the fundus
Patients experience significant pain
Associated systemic symptoms such as fever, nausea, vomiting, and headache
If the infection spreads through the superior ophthalmic vein to the cavernous sinus, it can cause cavernous sinus thrombosis. This may lead to restlessness, delirium, coma, convulsions, and bradycardia, potentially becoming life-threatening.
After controlling the inflammation, the lesions may become localized, resulting in the formation of purulent foci within the orbit. Due to the presence of various tissue compartments within the orbit, the purulent cavity can exhibit multiple locules or merge into a larger abscess. If the abscess ruptures through the skin or conjunctiva, the discharge of pus can temporarily relieve the proptosis (eyeball protrusion) symptoms.
Treatment:
For cases with a confirmed diagnosis, immediate and adequate systemic antibiotics should be administered to control the infection. Broad-spectrum antibiotics can be used initially to control the infection while performing conjunctival sac bacterial culture and drug sensitivity testing to identify the source of the infection and apply sensitive antibiotics. In cases with severe symptoms, short-term low-dose corticosteroid treatment may be considered to alleviate symptoms while infection control is ongoing. Diuretics may be used to reduce intraocular pressure, and antibiotic eye drops and ointments are applied to protect the cornea. In cases with incomplete eyelid closure, the use of a moist chamber may be attempted(quotes from therapeutique-dermatologique.org).
In cases where an intraorbital abscess forms, pus may be aspirated or drainage may be performed. For cases complicated by cavernous sinus inflammation, treatment should be actively pursued in collaboration with relevant specialists.