EuroSafe Imaging 2019
Action 2 - Clinical diagnostic reference levels (DRLs), Musculoskeletal system, Digital radiography, CT, Absorptiometry / Bone densitometry, Diagnostic procedure, Dosimetric comparison, Quality assurance
M. Adriaensen, K. Vanderdood, R. M. Kwee, A. Korsten, R. A. P. Borghans, B. JONG, R. Berendsen
Description of activity and work performed
All available DICOM-RDSR (Digital Imaging and Communication in Medicine – Radiation Dose Structured Report) for musculoskeletal diagnostic imaging examinations were retrospectively identified.
DICOM-RDSR were available from 4 digital X-ray machines and 3 CT-scanners [Table 1].
From 2 DXA-scanners (Dual X-ray Absorptiometry) dose information was manually extracted from the DICOM-images and for Scintigraphy systems dose calculations were based on administered activity [Table 1].
Only musculoskeletal examinations performed in the adult population (i.e.
equal or older than 18 years) were included if a minimum of 20 patients per acquisition protocol and machine were available.
A minimum number of 20 patients was choosen as the national Dutch DRLs are also calculated based on groups of at least 20 patients each.
Included examinations were performed between June 2013 and November 2018 for CT scans,
and between April 2018 and Oktober 2018 for conventional radiography and DXA studies.
DAP (Dose Area Product) in µGy.m2 per radiographic acquisition protocol was converted to ED (Effective Dose) in µSv based on the effective dose per unit DAP conform ICRP Publication 103 tissue factors [3,4].
Calculated ED are presented as mean +/- standard deviation [Table 2].
In case no conversion factors were known,
ED values were left blank.
DLP (Dose-Length Product) in mGy.cm per CT acquisition protocol was converted to ED in mSv based on mean DLP/ED conversion coefficients[-6].
Calculated ED are presented as mean +/- standard deviation [Table 3].
DAP (Dose Area Product) in µGy.m2 per DXA acquisition protocol was converted to ED (Effective Dose) in µSv similar to the conversion for conventional radiographic acquisitions.
Calculated ED are presented as mean +/- standard deviation [Table 4].
For bone scintigraphy 600 MBq of Technetium-99m hydroxymethylenediphosphonate was injected intravenously.
The injected dose in MBq was converted to ED in mSv conform ICRP 128 .
Resulting in an ED for adults with normal bone uptake of 2,94 mSv and an ED for adults with high bone uptake of 2,58 mSv.