Evaluation of technical image quality and radiation dose of a Thai cone-beam CT scanner

Authors

Ruben Pauwels
Saowapak Thongvigitmanee
Sorapong Aootaphao
Chalinee Thanasupsombat
Walita Narkbuakaew
Reinhilde Jacobs
Hilde Bosmans
Soontra Panmekiate
Pairash Thajchayapong

Publication Date

2017-01-01

Abstract

Objectives The aim of this study is to evaluate the technical image quality and radiation dose of the DentiiScan 2.0 cone-beam computed tomography (CBCT) scanner before widespread clinical use. Materials and methods Image quality was measured for 4 scanning protocols of the DentiiScan 2.0, using 2 dedicated test objects: the SEDENTEXCT IQ phantom and the QRM-ConeBeam phantom. The following image quality parameters were evaluated: contrast-detail, contrast-to-noise ratio (CNR), spatial resolution, grey value uniformity, metal artefacts, and geometric accuracy. Radiation dose was measured using a calibrated ionization chamber placed at the isocenter of rotation, allowing for the calculation of the dose-area product (DAP). Results For contrast-detail, scores were almost identical for all protocols, with all 5 rods being distinguishable for aluminium, air, hydroxyapatite 200 mg/cm3, polytetrafluorethylene, and low-density polyethylene. CNR values were commensurate with the contrast-detail results. Visual evaluation of the line pair patterns revealed considerable differences between scanning protocols. Some consistency between voxel size and sharpness could be seen. High grey value uniformity was found for Protocols 1-3; for Protocol 4 the uniformity was slightly worse. There was no difference in artefact severity between scanning protocols. For geometric accuracy, average errors between 0.04 and 0.08 mm were found, indicating high accuracy. The dose-area product was 897.1 mGy.cm2 for Protocol 1, 1058.4 mGy.cm2 for Protocol 2, 474.1 mGy.cm2 for Protocol 3, and 424.4 mGy.cm2 for Protocol 4. Conclusion The DentiiScan 2.0 showed adequate performance in terms of technical image quality, and a low radiation dose compared with other CBCT models. The protocol with the smallest FOV provided the best balance between image quality and dose.

DOI

10.58837/CHULA.CUDJ.40.1.3

First Page

27

Last Page

38

Recommended Citation

Pauwels, Ruben; Thongvigitmanee, Saowapak; Aootaphao, Sorapong; Thanasupsombat, Chalinee; Narkbuakaew, Walita; Jacobs, Reinhilde; Bosmans, Hilde; Panmekiate, Soontra; and Thajchayapong, Pairash (2017) "Evaluation of technical image quality and radiation dose of a Thai cone-beam CT scanner," Chulalongkorn University Dental Journal: Vol. 40: Iss. 1, Article 3.
DOI: 10.58837/CHULA.CUDJ.40.1.3
Available at: https://digital.car.chula.ac.th/cudj/vol40/iss1/3