Towards Personalised Contrast Injection: Artificial-Intelligence-Derived Body Composition and Liver Enhancement in Computed Tomography
Open Access
- 24 February 2021
- journal article
- research article
- Published by MDPI AG in Journal of Personalized Medicine
- Vol. 11 (3), 159
- https://doi.org/10.3390/jpm11030159
Abstract
In contrast-enhanced computed tomography, total body weight adapted contrast injection protocols have proven successful in achieving a homogeneous enhancement of vascular structures and liver parenchyma. However, because solid organs have greater perfusion than adipose tissue, the lean body weight (fat-free mass) rather than the total body weight is theorised to cause even more homogeneous enhancement. We included 102 consecutive patients who underwent a multiphase abdominal computed tomography between March 2016 and October 2019. Patients received contrast media (300 mgI/mL) according to bodyweight categories. Using regions of interest, we measured the Hounsfield unit (HU) increase in liver attenuation from unenhanced to contrast-enhanced computed tomography. Furthermore, subjective image quality was graded using a four-point Likert scale. An artificial intelligence algorithm automatically segmented and determined the body compositions and calculated the percentages of lean body weight. The hepatic enhancements were adjusted for iodine dose and iodine dose per total body weight, as well as percentage lean body weight. The associations between enhancement and total body weight, body mass index, and lean body weight were analysed using linear regression. Patients had a median age of 68 years (IQR: 58–74), a total body weight of 81 kg (IQR: 73–90), a body mass index of 26 kg/m2 (SD: ±4.2), and a lean body weight percentage of 50% (IQR: 36–55). Mean liver enhancements in the portal venous phase were 61 ± 12 HU (≤70 kg), 53 ± 10 HU (70–90 kg), and 53 ± 7 HU (≥90 kg). The majority (93%) of scans were rated as good or excellent. Regression analysis showed significant correlations between liver enhancement corrected for injected total iodine and total body weight (r = 0.53; p < 0.001) and between liver enhancement corrected for lean body weight and the percentage of lean body weight (r = 0.73; p < 0.001). Most benefits from personalising iodine injection using %LBW additive to total body weight would be achieved in patients under 90 kg. Liver enhancement is more strongly associated with the percentage of lean body weight than with the total body weight or body mass index. The observed variation in liver enhancement might be reduced by a personalised injection based on the artificial-intelligence-determined percentage of lean body weight.This publication has 37 references indexed in Scilit:
- CT Dose Reduction Applications: Available Tools on the Latest Generation of CT ScannersJournal of the American College of Radiology, 2013
- That liver lesion on MDCT in the oncology patient: is it important?Cancer Imaging, 2012
- Intravenous Contrast Medium Administration and Scan Timing at CT: Considerations and ApproachesRadiology, 2010
- Dual Source Dual Energy MDCTInvestigative Radiology, 2010
- Body Size Indexes for Optimizing Iodine Dose for Aortic and Hepatic Enhancement at Multidetector CT: Comparison of Total Body Weight, Lean Body Weight, and Blood VolumeRadiology, 2010
- Abdominal Multidetector CT in Patients with Varying Body Fat Percentages: Estimation of Optimal Contrast Material DoseRadiology, 2008
- Quantification of Lean BodyweightClinical Pharmacokinetics, 2005
- Contrast-Induced NephropathyAmerican Journal of Roentgenology, 2004
- CT and MR Imaging of Hepatic MetastasesAmerican Journal of Roentgenology, 2000
- Intravascular contrast media: adverse reactionsAmerican Journal of Roentgenology, 1987