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Published on: July 29, 2013
Contrast-to-noise ratio with different large volumes in a cone-beam computerized tomography machine: an in vitro
Boulos Bechara1, C Alex McMahan, William S Moore
1Department of Comprehensive Dentistry, University of Texas Health Science Center, San Antonio, Texas, USA. boulosbchara@hotmail.com
Objectives:
The objectives were to determine whether the images obtained from different cone-beam computerized tomography (CBCT) field of view (FOV) sizes with varying scan time and kilovolt peak using the Picasso Master 3D machine (Vatech, Hwasung, South Korea) differ in contrast-to-noise ratio (CNR).
Study Design:
A phantom was used. Scans were acquired using the same voxel size, 2 scan times (15 and 24 seconds) for 3 different FOV sizes and 5 different kilovolt peaks. The contrast and CNR were calculated for each FOV.
Results:
The CNRs were similar for the 2 scan times for all 3 FOV sizes. The CNR was lower in the 20 × 19 cm FOV compared with the other 2 FOVs for both scan times.
Conclusions:
The CNR does not vary significantly with increasing scan times for all FOV sizes. Smaller FOVs result in enhanced CNR and contrast.
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