Learning objectives
To understand the differences between child and adult low dose computed tomography (ldCT) protocols.
To provide a practical decision rule based on waist circumference for switching from a child to an adult protocol in ldCT of teenagers such that dose and image quality are optimized.
Background
PET/CT plays an important role in the teenager population for oncologic and inflammatory indications. Both PET and CT use ionizing radiation for imaging and are complementary to each other. PET provides functional information and the CT-scan is used for attenuation correction and anatomical correlation. For this, a ldCT protocol with sufficient image quality for anatomical correlation is enough. As teenagers are more radiosensitive than adults and have a long post exposure life expectancy in which the adverse radiation effects could exhibit, it is important to...
Findings and procedure details
LdCT scans were acquired on a 128 mCT scanner from cylindrical water/perspex phantoms with circumferences of 28, 31, 50, 63 and 100 cm (Fig. 1) using the clinical child and clinical adult protocols with an equal Quality reference CTDI (mGy). To understand the differences between these two protocols with respect to the AEC, the phantoms were also scanned with an adapted adult protocol based on the tube voltage, Quality reference mAs and Quality reference CTDI of the child protocol. The acquisition parameters used for the...
Conclusion
In teenagers with a waist circumference above 63 cm, an (adapted) adult protocol should be considered for optimal dose and image quality.
Personal information and conflict of interest
C. Cox; Rotterdam/NL - nothing to disclose M. van Straten; Rotterdam/NL - Research/Grant Support at Siemens Healthineers AG M. Segbers; Rotterdam/NL - nothing to disclose
References
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3.Reid J, Gamberoni J, Dong F, Davros W. Optimization of kVp and mAs for Pediatric Low-Dose Simulated Abdominal CT: Is It Best to Base Parameter Selection on Object Circumference? AJR 2010; 195:1015–1020
4.Dong F, Davros W, Pozutto J, Reid J. Optimization of Kilovoltage and...