Infection that involves the muscle and fat within the orbit - posterior to the orbital septum
More common in children than adults - 16x more
Differentiation between Periorbital cellulitis and orbital Cellulitis can be difficult in the initial stages of infection
Sight threatening condition
Approximately 11% of patients will have vision loss following orbital Cellulitis
Causes/Factors
- Local spreading infection of an acute bacterial Rhinosinusitis - typically from the paranasal sinuses
- Less common causes include the extension of Periorbital cellulitis, haematogenous spread, orbit trauma or contiguous spread from face or teeth from recent surgery or dental infection
Clinical Features
- Erythema and swelling around the eye
- Painful eye movements
- Change in colour vision
- Change in visual acuity/fields
- Proptosis
- Chemosis (swelling on conjunctiva)
- Relevant afferent pupillary defect (RAPD) - Marcus-Gunn pupil
- Fever
In the history must ask about:
- PMH - previous episodes of eye disease
- Cause - any precipitating cause
- Duration of symptoms
- Laterality (uni or bi)
- Severity of symptoms - worsening or improving
Exam look for:
- Nasal exam - ipsilateral nasal discharge
- Oral cavity exam - assess oral hygiene, any evidence of dental disease
- Examination of eyes and vision - visual fields, visual acuity, colour vision, pupil response, proptosis, slit lamp exam
- Neurological examination - Cranial Nerve Exam including assessment for meningism
Investigations
- FBC - may show elevated WBC - particularly neutrophilia
- CRP
- Lactate if patient is septic
- Blood cultures - Staph spp. Streptomyces spps. Haemophilus spps.
- MC&S
- Contrast enhanced CT head including orbit and sinuses
Management
- IV antibiotics 7-10 days - choice depends on local guidelines
- Surgical drainage of pus if abscess seen on imaging
Complications/red Flags
- Cavernous sinus thrombosis
- Loss of vision
- Intracerebral abscess
- Osteomyelitis
- Meningitis
- Death (rarely)