CONE BEAM COMPUTED TOMOGRAPHY SIALOGRAPHY: EFFECTIVE RADIATION DOSE REDUCTIONS WITH NOVEL IMAGING PROTOCOLS

BACKGROUND Many diseases and conditions can disrupt the normal function of the salivary glands, and imaging can be an important tool in the formulation of a diagnosis. With sialography being the imaging modality of choice for obstructive conditions of the major salivary glands, our group has previously demonstrated that cone beam computed tomography (CBCT) sialography offers enhanced visualization of inflammatory changes and obstructions, such as sialoliths and strictures, over plain film sialography.1 However, because ionizing radiation is a concern, optimizing imaging protocols is crucial in order to minimize the radiation dose to the patient while still producing images of high diagnostic quality. OBJECTIVE(S) As a first step in the optimization of a new imaging protocol for CBCT sialography, this study aimed to determine effective dose (E) for a range of exposure parameters using 2 field of view (FOV) sizes for submandibular and parotid gland CBCT sialography. STUDY DESIGN Using a RANDO male phantom, we determined site-specific radiation doses to 25 sites in the head and neck and calculated E across a range of operating kilovoltage peak and milliamperage settings of the J. Morita Veraview X800 (J. Morita Mfg. Corp., Kyoto, Japan). RESULTS The E for the submandibular gland study using an 8 cm (diameter) × 5 cm (height) FOV size ranged from 22.7 to 171.1 µSv, when varied across the unit's allowable kilovoltage peak and milliamperage range. For the parotid gland study using an 8 cm (diameter) × 8 cm (height) FOV size, the E ranged from 21.5 to 160.4 µSv. DISCUSSION/CONCLUSIONS The use of variable FOV sizes for the submandibular and parotid glands may allow reductions in E compared with our earlier work2 and allow us to further optimize sialography imaging protocols for future patients.