A 60 year old female presents with painful right neck swelling. She has a past medical history of alcoholic hepatic cirrhosis. Her vitals signs are within normal limits. On examination she has a mass in the right submandibular area. It is tender to palpation, but smooth with no fluctuance. The following images are obtained of the swollen mass.
Answer:Sialadenitis secondary to sialolithiasis
These bedside ultrasound images demonstrate an enlarged, hyperemic, right submandibular gland with evidence of a sialolith obstructing Wharton’s duct. There is no encapsulated fluid collection concerning for abscess. The patient was treated with antibiotics, sialagogues, and arranged to have close outpatient ENT follow-up. Repeat imaging at follow-up demonstrated stone passage and clinically her symptoms were resolving.
The submandibular gland is an exocrine gland that secretes saliva into the floor of the mouth via the submandibular (Wharton’s) duct.1
Sialolithiasis (salivary gland stone) occurs most commonly in the submandibular gland, where 85% of cases occur.1 This is believed to be due to the longer, upward path of the submandibular duct. The parotid gland is next most common at 15%.
Sialadenitis is inflammation of the salivary gland due to infection, obstruction, or both. The most common precipitant is obstruction by a sialolith. Initial management includes empiric antibiotics, sialagogues (e.g. sour candy, lemon juice), warm compresses, gland massage, and oral hydration.1
Ultrasound is the preferred first line imaging for sialolithiasis/sialadenitis with a sensitivity of 77%, specificity of 95%, PPV of 94%, and NPV of 78%.2 The vast majority of false negatives are due to stones less than 3mm, which are difficult to visualize. Computed Tomography is more sensitive than ultrasound, but because of radiation exposure it is reserved for ultrasound negative cases with high clinical suspicion.
Wilson KF, Meier JD, Ward PD. Salivary gland disorders. American family physician. 89(11):882-8. 2014. [pubmed]
Terraz S, Poletti PA, Dulguerov P. How reliable is sonography in the assessment of sialolithiasis? AJR. American journal of roentgenology. 201(1):W104-9. 2013. [pubmed]