CT radiation dose in children: a survey to establish age-based diagnostic reference levels in Switzerland

Abstract

This work aimed at assessing the doses delivered in Switzerland to paediatric patients during computed tomography (CT) examinations of the brain, chest and abdomen, and at establishing diagnostic reference levels (DRLs) for various age groups. Forms were sent to the ten centres performing CT on children, addressing the demographics, the indication and the scanning parameters: number of series, kilovoltage, tube current, rotation time, reconstruction slice thickness and pitch, volume CT dose index (CTDI(vol)) and dose length product (DLP). Per age group, the proposed DRLs for brain, chest and abdomen are, respectively, in terms of CTDI(vol): 20, 30, 40, 60 mGy; 5, 8, 10, 12 mGy; 7, 9, 13, 16 mGy; and in terms of DLP: 270, 420, 560, 1,000 mGy cm; 110, 200, 220, 460 mGy cm; 130, 300, 380, 500 mGy cm. An optimisation process should be initiated to reduce the spread in dose recorded in this study. A major element of this process should be the use of DRLs.

Nationwide survey of radiation exposure during pediatric computed tomography examinations and proposal of age-based diagnostic reference levels for Japan

“…Our survey also found that the DLP values for pediatric CT in Japan were higher than in other surveys [8][9][10][11]. The 75th percentile values of the CTDI vol for pediatric CT in our survey were higher than those in the survey conducted by the IAEA [10].…”

“…In the children group, 17% (164/970), 9% (89/970) and 10% (93/970) were for head, chest and abdominal CT scans, respectively. Tables 3 and 4 show the comparison between CTDI vol and DLP values obtained in the present study with those from other published surveys from the United Kingdom, Germany, Switzerland, Thailand and the International Atomic Energy Agency (IAEA) [6][7][8][9][10]. All age-based 75th percentiles of the CTDI vol values for the head were 1-2 times higher and DLP values for the head were 0.9-1.9 times higher in the Japanese survey than in the other published surveys.…”

“…All age-based 75th percentiles of the CTDI vol values for the head were 1-2 times higher and DLP values for the head were 0.9-1.9 times higher in the Japanese survey than in the other published surveys. The 75th percentile of the CTDI vol values for the chest were 1.4-3.2 times higher and the DLP values for the chest were 1.4-3.8 times higher in the Japanese survey than those reported from the German, Swiss, Thai and French surveys [7][8][9]11] and nearly equal to the results reported for the British and IAEA surveys [6][7][8][9][10]. The 75th percentile of the CTDI vol values for the abdomen were 1.2-2.4 times higher and the DLP values for the abdomen were 1.1-2 times higher in the Japanese survey than in the German, Swiss, Thai and French surveys [7][8][9]11] and lower than in the British and IAEA surveys [6][7][8][9][10].…”

Nasolabial cysts − a rare case

“…12,13,14,15 This may be a reflection of a suboptimal radiographic technique, because DLP is proportional to scan length. For instance, the local mean scan length in the 0-2 years age group was found to exceed the range of scan lengths of 9.0 -13.5 cm noted in the European and Australian studies.…”

Implementation of Dose Monitoring Software in the Clinical Routine: First Experiences

“…Due to the versatile use of CT [12,13], the number of CT studies has continuously increased during the last decades [1, 2, 14,15]. At the same time radiation exposure of the public from medical sources has grown by approximately 600 % to reach 3.0 mSv per capita per year [16,17] and it is expected that 1 -2 % of all can- cers in the United States will be attributable to CT scans in the future [18 -20].…”