A comparative study of the diagnostic capabilities of 2D plain radiograph and 3D cone beam CT sialography
ABSTRACT Objective The aim of this study was to compare the diagnostic capabilities of two-dimensional sialography with a novel three-dimensional technique using cone beam CT (CBCT). Methods 47 subjects underwent parotid or submandibular gland sialography over a 2 year period using both plain imaging and CBCT. Both image sets were anonymized and independently reviewed by three certified oral and maxillofacial radiologists blinded to the clinical data. McNemar's χ(2) test was used to determine differences between the two modalities for feature visualization and interpretation. Results CBCT outperformed plain imaging with respect to visualization of the gland parenchyma (p < 0.001) and identification of sialoliths (p = 0.02). Plain imaging outperformed CBCT for the identification of strictures (p = 0.04); however, the negative per cent agreement ("specificity") between the two imaging modalities was 100%. Although both imaging modalities performed equally in identifying normal and abnormal sialographic examinations, CBCT demonstrated a high negative per cent agreement for normal glands and a high positive per cent agreement ("sensitivity") for abnormal glands with inflammatory changes. Conclusion CBCT sialography allowed better visualization of gland parenchyma and identification of sialoliths. The high negative per cent agreement for strictures suggests that, if strictures are identified on CBCT images, then obstruction can be ruled in. Relative to plain images, the high negative per cent agreement for normal glands suggests that, if an abnormal finding is detected on CBCT images, then disease can be ruled in, and the high positive per cent agreement for glands with inflammatory changes suggests that inflammation can be ruled out if these changes are not seen on CBCT images.
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ABSTRACT: Cone beam computed tomography (CBCT) is being widely used in recent years and has modernized the practice of oral and maxillofacial radiology by its inherent advantages, such as short scanning time, high resolution, and low dose of radiation to the patient. Sialography can be considered as the second step of assessment of space-occupying masses after initial diagnosis with ultrasonography. Sialography is combined with plain radiographs in routine practice. It can also be combined with advanced modalities such as computed tomography (CT), magnetic resonance imaging (MRI), and CBCT. In this report, we describe 3 cases to confirm the feasibility and superiority of sialography using CBCT and 3-dimensional (3D) images in space-occupying lesions of major salivary glands when conventional sialography is not diagnostic or MRI and CT are not easily available or affordable. CBCT sialography and its 3D images can be helpful in the diagnosis of space-occupying lesions of major salivary glands.03/2014; 117(6). DOI:10.1016/j.oooo.2014.02.023
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ABSTRACT: Objectives The aim of this study was to reveal the three-dimensional fluctuation of voxel values in a uniform material placed inside a phantom simulating a human head when it was scanned with cone-beam computed tomography (CBCT) for dental use. Methods We employed a cylindrical acrylic phantom to simulate a human head. Iodine solution, water, or air was placed inside the phantom, which was then scanned using CBCT. Regions of interest (ROIs) were set on the obtained CBCT images, and the mean voxel value in each ROI was measured. Finally, the profiles of the voxel values in the bottom-to-top (BT) and anterior-to-posterior (AP) directions in the field of view (FOV) were investigated. Results For the BT direction, the voxel values were almost constant regardless of the slice position (standard deviation: Conclusions Three-dimensional fluctuation of voxel values was evaluated for uniform scan targets on CBCT scanning. In the longitudinal direction, the voxel values were almost constant. However, in the axial plane, the fluctuation was so large that estimation from voxel values might not be reliable.Oral Radiology 09/2014; 30(3):226-235. DOI:10.1007/s11282-014-0169-1 · 0.15 Impact Factor