Coronal and sagittal CT images show an enlarged left submandibular gland with two well-defined rim enhancing fluid collections in the anterior aspect of the gland, representing abscesses. There is adjacent subcutaneous fat stranding.
- Most common salivary gland abnormality is infection, either bacterial or viral
- Bacterial infection ascends from oral cavity. Most common pathogens are S. aureus, S. viridans, H. influenza
- Most common viral infection is mump
- Most common site = parotid > submandibular gland
- Predisposing factors are dehydration, radiation, immunosuppression
- Other causes of sialadenitis include inflammation (sialolithiasis, radiation), autoimmune (Sjogren, lupus), granulomatous (TB), drug, etc.
Sialadenitis vs Abscess
- Sialadenitis is treated with antibiotics, while abscess usually needs surgery
- Abscess may spread to deep neck spaces and progress to Ludwig angina
- CT can differentiate the two entities. Abscess is seen as localized low attenuation, walled-off region in contrast to dense, enhanced gland
- CT can show calcified sialolithiasis, and in some cases noncalcified sialolithiasis as a cause of duct obstruction
1. Yoskovitch A. Submandibular sialadenitis/sialadenosis. emedicine Jul 23, 2008.
2. Silvers AR, Som PM. Salivary glands. Radiol Clin North Am 1998;36:941-966.