Standardization of terminology, imaging features, and interpretation of CBCT sialography of major salivary glands: a clinical review

Sialography combined with cone beam computerized tomography (sialo-CBCT) is an imaging technique that demonstrates the ductal system of the major salivary glands and allows evaluation of gland function. This review describes the sialo-CBCT technique, terminology, common pitfalls and limitations, as well as radiographic features and suggested pathogenicity of various salivary gland disorders, based on 1,758 sialo-CBCT examinations conducted over the last decade in one institution, and the current literature. The adoption of standardized terminology is proposed to prevent miscommunication, facilitate formulation of differential diagnoses, and thereby promote patient management: (1) Sialo-CBCT requires specific training, and operator experience is required for adequate glandular filling with minimal extravasation; (2) Limit injection-to-scan time to avoid pre­mature emptying; (3) The sialo-CBCT report should include a description of the morphology of the primary duct as well as the secondary, tertiary, and descending branches, the maximal branching level, the presence of sialectasis, overall glandular size, and parenchymal findings; (4) Functional evaluation is based on assessment of iodine clearance in the post evacuation image; (5) Sialectasis and ductopenia are the main findings in Sjogren syndrome and recurrent juvenile parotitis; (6) Sialodochitis with or without fillings defects or hyperdense calcifications characterize obstructive sialadenitis and sialolithiasis; (7) The findings following radioactive-iodine-induced damage are similar to obstructive sialadenitis, with atrophy in late stages; (8) In chronic graft-versus-host disease (cGVHD), variable presentations of ductopenia, sialectasis, and sialodochitis may be evident; (9) The red flags indicating a space-occupying lesion include areas of no filling, splaying of ducts, and primary duct deviation.