Sialosis (Sialadenosis): A Sialographic Study with Clinical Correlates.

Objective: Characterize radiographic findings and co-existing pathologic processes in the parotid glands of patients with swelling or pain identified on radiographic review to be consistent with sialosis (sialadenosis) employing dynamic infusion digital sialography correlated with computed tomography (CT).

Methods: Retrospective chart review of a consecutive series of 578 sialograms performed by the senior investigator over a 16-year period identified 39 patients with 1 or both parotid gland sialograms recorded as "sialosis" by radiologists' interpretation. After inclusion and exclusion criteria were applied, 20 patients remained for evaluation. A review of sialograms was conducted by a senior radiologist to identify co-existing pathologies (ex: stricture, sialectasis, sialolith) as well as characterize an overall aggregate impression and specific findings of ductal curvature, splaying, and truncation on a numerical scale from 1 (absent finding) to 10 (severely abnormal). Two normal sialograms served as controls. The density of each gland was assessed through CT measurement of Hounsfield units (HU). Variables collected included sex, age, symptoms, BMI, alcohol use, and comorbidities.

Results: Twenty patients with a total of 27 glands classified as "sialosis" on sialography and 2 patients with normal sialography findings were evaluated. Indications for sialography included pain (90%), fluctuation in swelling of the parotid gland(s) (65%), or xerostomia (35%). Sialographic analysis identified 7 glands (26%) with sialosis to have an additional co-existing pathology (2 with strictures, 5 with sialectasis). Consistent features in glands with sialosis included ductal curvature, splaying, and truncation. CT analysis of glands with sialosis identified a median HU measurement of -36 compared to +30 for glands identified as normal (P = .03).

Conclusion: Sialography is useful in selected patients to evaluate for co-existing pathologies contributing to salivary symptoms. Sialography additionally demonstrates consistent findings (ductal curvature, splaying, and truncation) associated with sialosis that correlate with fat infiltration identified on CT imaging.