Orbital Cellulitis-When Computed Tomography Imaging Is Falsely Reassuring

Area of Science:

• Ophthalmology
• Pediatric Emergency Medicine
• Radiology

Background:

• Orbital cellulitis is a serious infection that requires prompt diagnosis and treatment.
• Sinusitis is a common predisposing factor for orbital cellulitis in children.
• Computed tomography (CT) is often the initial imaging modality used.

Observation:

• An 8-year-old boy presented with fever, blurry vision, and left eye pain.
• Initial physical examination revealed left lower lid erythema and mild eye movement deficit.
• CT scan showed paranasal sinus opacification but no clear orbital involvement.

Findings:

• Despite a negative CT scan, clinical suspicion led to treatment for orbital cellulitis.
• Subsequent magnetic resonance imaging (MRI) revealed orbital fat stranding and inferior rectus muscle abnormalities.
• MRI confirmed the diagnosis of orbital cellulitis, particularly near the orbital apex.

Implications:

• This case highlights the diagnostic limitations of CT in subtle orbital cellulitis.
• MRI is a valuable tool for definitive diagnosis when CT is equivocal.
• Early and accurate diagnosis of orbital cellulitis is critical to prevent vision loss and complications.