Keywords:
Radioprotection / Radiation dose, Professional issues, CT, Experimental, Technical aspects, Dosimetry, Health policy and practice, Quality assurance, Dosimetric comparison, Occupational / Environmental hazards
Authors:
J. P. Pinheiro1, B. P. M. Morgado2, A. F. Abrantes1, L. P. V. Ribeiro1, P. Sousa1, R. P. P. Almeida1, S. Rodrigues1, K. B. Azevedo1; 1Faro/PT, 2Vila Real de Santo António/PT
DOI:
10.1594/ecr2016/C-2363
Results
It was possible to verify,
despite the relation between the contrast-to-noise ratio (CNR) and the current-time product isn´t absolutely linear,
there is a CNR increasing/decreasing when current-time product increase/decrease,
respectively (Fig.7).
It is also known that there are limits below which the CNR (0.7 for paediatric head and 0.4 for paediatric abdomen) is no longer acceptable,
so reducing the current-time product must be done in a thoughtful way.
Fig. 7: CNR in paediatric head CT examinations
References: Medical Imaging and Radiotherapy Department, Health School - University of Algarve, Portugal.
The dose reduction achieved was 25,9% for head CT examinations in newborn patients,
13,8% for patients until 1 year,
25,9% for patients between 1 and 5 years old,
and 14,9% for patients until 10 years old,
without deteriorating the diagnostic quality of the image (Fig.8).
Fig. 8: Fig. 8 – Dose reduction in paediatric head CT examinations
References: Medical Imaging and Radiotherapy Department, Health School - University of Algarve, Portugal.
About the exposures performed with Abdomen/Chest protocols doesn’t exist valid results,
what is presumed to be linked to the fact that it was used the automatic exposure control (AEC).