Parotitis

Axial CT image of the neck shows an enlarged left parotid gland (star) with blurry margins, nearby fat stranding. There is no internal low attenuation areas.

Facts:

• Infection of the parotid gland caused by bacterial, viral pathogen or is calculus-induced.
• Acute suppurative parotitis is usually unilateral
• Bacterial parotitis is usually caused by S aureus (greater than 50% of cases) and anaerobic bacteria
• May be complicated by abscess formation, thrombophlebitis, cranial nerve VII dysfunction
• Treatment: hydration, antibiotics, possible drainage if an abscess develops

CT Findings:

• Diffuse enlargement and enhancement of the parotid gland
• Blurred margins of the gland
• Internal low attenuation indicative of abscess formation

Reference:

Capps EF, Kinsella JJ, Gupta M, et al. Emergency imaging assessment of acute, nontraumatic conditions of the head and neck. Radiographics 2010; 30:1335-1352.