Which dose index should be used for establishing DRL in dental CBCT?

Congress:

EuroSafe Imaging 2019

Poster Number:

ESI-0067

Type:

EuroSafe Imaging

Keywords:

Action 2 - Clinical diagnostic reference levels (DRLs), Radiation physics, Cone beam CT, Diagnostic procedure, Dosimetric comparison

Authors:

I. Kralik, B. Brkljacic, T. Lauc, H. Brkic, J. Popic, H. Vavro, D. Faj

DOI:

10.26044/esi2019/ESI-0067

DOI-Link:

https://dx.doi.org/10.26044/esi2019/ESI-0067

Fig. 1: Measurement of CBCT dose indices. Black dots denote possible positions of...

Fig. 2: Part of the PPMA phantom (left) and radiochromic film (right) which were used...

Fig. 3: Computational anthropomorphic phantom ("Zubal") which was used in this study -...

Table 1: Most often clinical protocols

Background/introduction

Different performance of devices used in case of patients undergoing dental cone beam computed tomography (CBCT) examinations as well as procedure itself may result in complex dose distribution within the patient [1]. At the moment, depending on publication, three dosimetric quantities (dose indices) are suggested to be used as representation of patient dose: CT dose index (CTDI) [2], CBCT dose indices (CBCTDI1 and CBCTDI2) or dose-area product (DAP) [1, 3]. CBCT dose indices, CBCTDI1 and CBCTDI2 were proposed by the SEDENTEXCT project [1]. CBCTDI1 is...

Description of activity and work performed

For the purpose of investigation, Monte Carlo simulation was used and experimental measurements were performed. CBCT dental unit was simulated using Monte Carlo N-Particle transport code (MCNP® 6.1.1beta) and model verification was performed using PMMA head CTDI phantom and radiochromic films (Figure 2) as described in previously published study [5]. For calculation of organ doses and for the assessment of effective doses computational anthropomorphic phantom was used („Zubal“) (Figure 3) [6, 7]. Most often clinical protocols involving different exposure geometries including sizes and positions of...

Conclusion and recommendations

Because DAP is easily measurable and it shows strong linear correlation with effective dose, it should be used for establishing DRL in case of dental CBCT examinations.

Personal/organisational information

I. Kralik1, B. Brkljacic2, T. Lauc3, H. Brkic3, J. Popic4, H. Vavro1, D. Faj3; 1University Hospital Dubrava, Zagreb/HR 2University of Zagreb, Zagreb/HR 3Josip Juraj Strossmayer University of Osijek, Osijek/HR 4University Hospital Merkur, Zagreb/HR [email protected]

References

[1] Pauwels R, Theodorakou C, Walker A, Bosmans H, Jacobs R, Horner K and Bogaerts R 2012 Dose distribution for dental cone beam CT and its implication for defining a dose index Dentomaxillofacial Radiol. 41 583–93 [2] IAEA Technical Reports Series no: 457. Dosimetry in Diagnostic Radiology: An International Code of Practice. 2007. [3] European Commission. Cone Beam CT for Dental and Maxillofacial Radiology: Evidence Based Guidelines. Radiation Protection Publication 172. 2012 [4] Araki K, Patil S, Endo A, Okano T. Dose indices in dental...