Xray - CT

Conventional Sialography vs CT

Plain radiographs are insensitive in detection of salivary gland/duct calculi. Sialography is an accurate technique but invasive and often painful for the patient. In addition, the submandibular duct is frequently difficult to cannulate.

Low dose screening CT (similar to CTU for renal colic) is the most sensitive test for detecting calculi. It is non-invasive and rapid and can be performed using a low radiation technique. Plain films are no longer necessary.

The multi detector CT at St George's Radiology is particularly suited to this examination, being able to perform a low radiation dose examination with supplementary sagittal and coronal images. These are often valuable in surgical planning.

Sialography should be reserved for suspected sialectesis, Sjogrens disease and suspected strictures where CT has failed to identify calculi. Ultrasound and contrast enhanced CT remain the first line modalities for investigation of a salivary gland mass with MRI reserved for problem solving.

Dr Mark Coates
ENT Radiologist
CHRISTCHURCH RADIOLOGY GROUP