Keywords:
Physics, CT, Radiographers, Trauma
Authors:
T. Esaki, T. Kawashima; Shimotsuke City/JP
DOI:
10.26044/ecr2019/C-0129
Results
CT Value of eFOV
When eFOV was Without Bolus,
the CT value decreased from offset 1 cm or more.
The CT value was the lowest at offset 4 cm.
With Bolus,
the CT value decreased from offset 2 cm or more.
In Offset 4 cm,
the CT value was not improved by Bolus,
and the CT value was reduced to -400 HU.
There was no large CT value difference between Bolus 0.5 cm and Bolus 1 cm.
The CT value improved by 61% at the maximum by Bolus until Offset 3 cm,
but not improved at offset 4 cm,
5 cm (Fig. 6).
CT Value of HD FOV Pro
Without Bolus and With Bolus,
CT value decreased from offset 0 cm.
However,
CT value after offset 3 cm was improved over eFOV.
The position with the smallest CT value was offset 5 cm.
The minimum CT value was Without Bolus: -173 HU,
Bolus 0.5 cm: -132 HU,
Bolus 1.0 cm: -106 HU,
CT value was greatly improved compared with eFOV.
In addition,
Bolus contributed to the improvement of CT value with all offsets (Fig. 7).
Distortion
Without Bolus,
Distortion increased in proportion to offset regardless of algorithm (Fig. 8)(Fig. 9).
However,
compared to eFOV,
HD FOV Pro improved distortion with all offsets.
Distortion improved by Bolus,
but there was no difference in improvement effect between Bolus thickness and algorithm.