Orbital cellulitis Flashcards
What is orbital cellulitis?
An infection affecting the fat and muscles posterior to the orbital septum, within the orbit but not involving the globe.
What is the usual cause of orbital cellulitis?
A spreading upper respiratory tract infection from the sinuses.
Is orbital cellulitis a medical emergency?
Yes, it requires hospital admission and urgent senior review.
What is periorbital (preseptal) cellulitis?
A less serious superficial infection anterior to the orbital septum.
What can cause periorbital cellulitis?
Superficial tissue injury (chalazion, insect bite, etc.).
Can periorbital cellulitis progress to orbital cellulitis?
Yes, it can progress.
What are the risk factors for orbital cellulitis?
- Childhood
- Mean age of hospitalization 7-12 years
- Previous sinus infection
- Lack of Haemophilus influenzae type b (Hib) vaccination
- Recent eyelid infection/insect bite on eyelid
- Ear or facial infection
What are common presentations of orbital cellulitis?
- Redness and swelling around the eye
- Severe ocular pain
- Visual disturbance
- Proptosis
- Ophthalmoplegia/pain with eye movements
- Eyelid oedema and ptosis
- Drowsiness +/- Nausea/vomiting in meningeal involvement (Rare)
What symptoms indicate orbital cellulitis over preseptal cellulitis?
Reduced visual acuity, proptosis, ophthalmoplegia/pain with eye movements.
What investigations are used for orbital cellulitis?
- Full blood count - WBC elevated, raised inflammatory markers
- Clinical examination - Decreased vision, afferent pupillary defect, proptosis, dysmotility, oedema, erythema
- CT with contrast - Inflammation of the orbital tissues, sinusitis
- Blood culture and microbiological swab
What are the most common bacterial causes of orbital cellulitis?
- Streptococcus
- Staphylococcus aureus
- Haemophilus influenzae B
What is the management for orbital cellulitis?
Admission to hospital for IV antibiotics.
