Salivary Obstruction Investigation — ORE Part 1 MCQ
Instant feedback + full explanation. One question, done properly.
Educational content. Not a substitute for clinical judgement or local policy.
Reveal the answer and explanation
Correct answer: B — Ultrasound of the affected salivary gland
Ultrasound is the appropriate first-line investigation for suspected salivary gland obstruction. It is non-invasive, radiation-free, highly sensitive (>90% sensitivity for obstructive disease including sialolithiasis and duct strictures), widely accessible in primary and secondary care, and cost-effective. It readily identifies ductal dilatation, calculi, and glandular swelling. CT and MRI, while offering superior ductal detail, are reserved for problem-solving or specialist assessment when ultrasound is inconclusive or surgical planning is needed. Conventional sialography is an invasive, second-line investigation used to visualise intrinsic ductal abnormalities and is now largely replaced by non-invasive cross-sectional imaging. Empirical treatment without imaging risks missing serious pathology (e.g., malignancy mimicking obstruction) and is clinically unsafe.
Reference: Koch M, et al. Ultrasound in Inflammatory and Obstructive Salivary Gland Diseases. Journal of Clinical Medicine. 2021;10(16):3547. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8397054/; Royal Devon University Healthcare NHS Foundation Trust. Patient Information Leaflet: Having a Sialogram. 2024. https://www.royaldevon.nhs.uk/media/cp2bgzyo/patient-information-leaflet-having-a-sialogram-rde-20-170-002.pdf; SDCEP MADP. Salivary gland obstruction or infection. https://madp.sdcep.org.uk/content/conditions-library/salivary.html