Reduction of scatter-induced image noise in cone beam computed tomography: effect of field of view size and position

作者：Pauwels Ruben^*; Jacobs Reinhilde; Bogaerts Ria; Bosmans Hilde; Panmekiate Soontra

来源：Oral Surgery Oral Medicine Oral Pathology Oral Radiology, 2016, 121(2): 188-195.

DOI：10.1016/j.oooo.2015.10.017

Objective. To measure the effect of field of view (FOV) size and position on scatter-induced image noise in cone beam computed tomography (CBCT).
Study Design. A polymethyl methacrylate (PMMA) phantom containing air and aluminum underwent CBCT scanning, using seven FOVs ranging between 4 x 4 cm and 14 x 10 cm, positioned both centrally and according to a dental scan. Signal difference to noise ratio (SDNR) was measured on two-dimensional (2-D) projection images.
Results. At a central position, SDNR decreased with increasing FOV size, ranging between 9.8 (14 x 10 cm) and 10.9 (4 x 4 cm). For dental FOV positions, SDNR values were between 6.3 (14 x 10 cm) and 9.5 (4 x 4 cm). To reach a constant SDNR, a dose reduction up to 76% was possible for small FOVs compared with the 14 x 10 cm FOV.
Conclusions. The use of small FOVs and peripheral FOV positioning decreases scatter at the detector, resulting in a considerable potential for reduction of radiation dose to the patient.

• 出版日期2016-2