CHEST CT RADIATION EXPOSURE: DOSE-OPTIMISATION STRATEGIES

Congress:

EuroSafe Imaging 2017

Poster Number:

ESI-0040

Type:

EuroSafe Imaging

Keywords:

Radiation safety, Radiation effects, Diagnostic procedure, CT-Quantitative, CT, Radioprotection / Radiation dose, Breast, Action 8 - Radiation protection training and learning material, Action 2 - Clinical diagnostic reference levels (DRLs), Action 6 - Education and training in medical radiation protection, Action 3 - Optimisation, diagnostic reference levels, image quality, Dosimetric comparison, Image verification

Authors:

M. Gentile, A. Morasca, A. del Ciello, M. Modestini, A. Guidi, C. lombardozzi, L. Indovina, A. Piermattei, L. Bonomo

DOI:

10.1594/esi2017/ESI-0040

DOI-Link:

https://dx.doi.org/10.1594/esi2017/ESI-0040

Fig. 1: Phantom set-up

Fig. 2: CATPHAN T600 phantom and two anthropomorphic RANDO ALDERSON type breasts

Table 1: Table doses in different series

Fig. 3: Topogram Dose

Fig. 4: Dose variations in different series

Table 2: Table quality in different series

Fig. 5: Image quality in different series

Background/Introduction

The dose patient optimization must be obtained through the correct use of technologies (tools), available especially in CT, for dose modulation. Very often, it is not immediate for radiologists, technicians and physicists how to integrate different available technologies and in this sense attention should be paid to understand which integration is the best to ensure the correct balance between image quality and patient dose. In order to provide guidance in this aspect, this study is focused on the tools which permit modulation dose in the...

Description of activity and work performed

The study was carried out on a CT system that uses an "automatic exposure control" (Fig. 1), combining automatic adjustment of tube current in the x, y plane (angular modulation) and along the scanning direction (z-axis modulation) with the following three technologies: CARE Dose 4D performs z-axis modulation based on attenuation data obtained from single localizer radiograph (topogram) and real-time angular modulation for each tube rotation. X-Care protects the breasts of the Patient. The tube current is reduced in a predefined area at the front...

Conclusion and Recommendations

The Image quality does not show important and significant differences between all scan series: the image quality parameters guarantee the expected levels defined on the Italian regulatory (D.Lvo 187/0). (Fig. 5 Table 2). The best modulation dose is performed with the posteroanterior locator (tube position Bottom), activating the CAREDose4D, X Care and the SAFIRE iterative reconstruction algorithm. (Fig. 4 Table 1). It is mandatory for routine practice to reach optimization in the technologies setup available for dose modulation in RX imaging as presented in this...

Personal/Organisational information

Dose-Optimization Strategies are organized in our hospital by Technicians, Medical Physicists and Radiologists according to Euratom directives and Italian laws. Diagnostic Procedures are periodically revisited to improve dose and image quality optimization.

References

Mannudeep K. Kalra, Stefania M. R. Rizzo, Robert A. Novelline "Reducing radiation dose in emergency computed tomography with automatic exposure control techniques" - Emergency Radiology (12-may-2005)11:267-274 Kalender WA, Wolf H, Suess C, Gies M, Greess H, Bautz WA (1999) "Dose reduction in CT by on-line tube current control: principles and validation on phantoms and cadavers". Eur Radiol 9:323-328 Vollmar SV, Kalender WA. "Reduction of dose to the female breast in thoracic CT: a comparison of standard-protocol, bismuth-shielded, partial and tube-current modualted CT examinations". Eur Radiol....