Room: Exhibit Hall | Forum 1
Purpose: Cardiac CT scan is considered as one of CT procedures that delivers a high dose to patients. The aim of this study is to quantify and compare between doses resulting from cardiac scans acquired with two new models of CT scanners installed recently in our institution.
Methods: CT scans acquired for adults (AD) and paediatric (PD) patients with Somatom Force (Siemens) and Revolution CT (GE) were analysed retrospectively using a commercial dose tracking software application, DoseTrack (SECTRA). Doses from 106 scans (AD=69, PD=37) and 110 scans (AD=79, PD=31) acquired with the GE and Siemens scanners, respectively, were studied. The dose comparison between the scanners were based on the dose indices CTDIvol and dose length product (DLP) of a clinical scan protocol required acquiring images with contrast and in wide-beam configuration (CBCT).
Results: Mean values of CTDIvol for adults and paediatric scans acquired with the Siemens scanner were 22.4 (4.5 â€“ 97.9) mGy and 6.1 (0.2 â€“ 43.7) mGy, respectively, while CTDIvol values of the GE scanner were 21.6 (4.5 â€“ 66.6) mGy and 6.0 (0.7 â€“ 28.5) mGy, respectively. Mean DLP values of the Siemens scanner were 390.7 (39.7 â€“ 2123.3) mGy.cm for adults and 55.5 (2.9 â€“ 621.1) mGy.cm for paediatric, whereas DLP values for the GE scanner were 321.1 (45.9 â€“ 1120.3) mGy.cm and 57.7 (6.2 â€“ 371.7) mGy, respectively.
Conclusion: Although the mean values of CTDIvol and DLP for both scanners are comparable, the dose ranges for the Siemens scanners were larger by up to a factor of 1.5 for CTDIvol and 1.9 for DLP than those for the GE scanner. The reasons for the differences in the dose ranges are currently being investigated.
Not Applicable / None Entered.