Conversion coefficients for the estimation of effective dose in cone-beam CT.
- Author:
Dong Soo KIM
1
;
Oyuntugs RASHSUREN
;
Eun Kyung KIM
Author Information
- Publication Type:Original Article
- Keywords: Radiation Dosage; Radiography, Dental; Cone-Beam Computed Tomography; Effective Dose
- MeSH: Adult; Cone-Beam Computed Tomography*; Head; Humans; Incisor; Male; Mandible; Maxilla; Molar; Neck; Radiation Dosage; Radiography, Dental
- From:Imaging Science in Dentistry 2014;44(1):21-29
- CountryRepublic of Korea
- Language:English
- Abstract: PURPOSE: To determine the conversion coefficients (CCs) from the dose-area product (DAP) value to effective dose in cone-beam CT. MATERIALS AND METHODS: A CBCT scanner with four fields of view (FOV) was used. Using two exposure settings of the adult standard and low dose exposure, DAP values were measured with a DAP meter in C mode (200mm x 179 mm), P mode (154 mm x 154 mm), I mode (102 mm x 102 mm), and D mode (51 mm x 51 mm). The effective doses were also investigated at each mode using an adult male head and neck phantom and thermoluminescent chips. Linear regressive analysis of the DAP and effective dose values was used to calculate the CCs for each CBCT examination. RESULTS: For the C mode, the P mode at the maxilla, and the P mode at the mandible, the CCs were 0.049 microSv/mGycm2, 0.067 microSv/mGycm2, and 0.064 microSv/mGycm2, respectively. For the I mode, the CCs at the maxilla and mandible were 0.076 microSv/mGycm2 and 0.095 microSv/mGycm2, respectively. For the D mode at the maxillary incisors, molars, and mandibular molars, the CCs were 0.038 microSv/mGycm2, 0.041 microSv/mGycm2, and 0.146 microSv/mGycm2, respectively. CONCLUSION: The CCs in one CBCT device with fixed 80 kV ranged from 0.038 microSv/mGycm2 to 0.146 microSv/mGycm2 according to the imaging modes and irradiated region and were highest for the D mode at the mandibular molar.
