TITLE:
Optimization of Contrast Material Dose for Abdominal Multi-Detector Row CT: Predicting Patient Lean Body Weight by Using Preliminary Transverse CT Images
AUTHORS:
Antonino Guerrisi, Daniele Marin, Huiman Barnhart, Lisa Ho, Thomas L. Toth, Carlo Catalano, Rendon C. Nelson
KEYWORDS:
Lean Body Weight; Multi-Detector CT; Contrast Dose
JOURNAL NAME:
Advances in Computed Tomography,
Vol.3 No.1,
March
28,
2014
ABSTRACT: Estimated
LBW could be used to determine the contrast material dose and rate during MDCT. The aim
of this study is to test the accuracy of a technique for estimation of lean
body weight (LBW) from a single multi-detector row computed tomographic (MDCT)
abdominal image, using a bioelectrical body composition analyzer scale as the
reference standard. CT images of 21 patients with previously measured LBW
(mLBW) were processed using computer-assisted, vendor-specific software
(Advantage Windows 4.2; GE Healthcare, Inc). For each transverse image, a
fat-fraction was automatically measured as the number of fat pixels (-200 to -50 HU) divided by the
total number of pixels having an attenuation value ≥-200 HU. Estimated LBW (eLBW) of five single
contiguous sections was calculated in each of three abdominal regions (upper
abdomen, mid abdomen and pelvis) by multiplying TBW by (1 – fat-fraction).
Bland-Altman plot with limits of agreement was used to assess agreement between
mLBW and eLBW. The mean mLBW for all patients was 56 kg (range, 39 - 75 kg).
Mean differences and limits of agreement between mLBW and eLBW measurements for
the upper abdomen, mid abdomen and pelvis reported were -8.9 kg (-25.6 kg, +7.5 kg), -10.6 kg (-27.7 kg, +6.4 kg), and
+0.5 kg (-12.8 kg,
+13.8 kg) respectively. eLBW deriving directly from a transverse CT image of
the pelvis can accurately predict mLBW.