Low-contrast Dose Liver CT Using Lean Body Weight Low Monoenergetic Images and Deep Learning-based Reconstruction

Low-contrast Dose Liver CT Using Lean Body Weight Low Monoenergetic Images and Deep Learning-based Reconstruction

Low-contrast Dose Liver CT Using Lean Body Weight, Low Monoenergetic Images and Deep Learning-based Reconstruction for Hepatocellular Carcinoma

This study aims to assess whether the acceptable image quality is achievable using low monoenergetic imaging of dual-energy CT with deep learning-based denoising, and low contrast media dose calculated based on lean body weight for the detection of hepatocellular carcinoma.

The use of iodinated contrast media in CT is associated with an immediate hypersensitivity reaction in a dose-dependent manner. Therefore, it is important to reduce the contrast dose for CT exams in patients who are required repeated CT examinations, including patients with hepatocellular carcinoma (HCC). Low monoenergetic images of dual-energy CT can provide higher iodine contrast than conventional images, thus enabling reduction of contrast media. The high image noise in low monoenergetic images may be improved by using model-based IR techniques and deep learning-based denoising (DLD) algorithms. Besides, lean body weight (LBW)-based contrast dose determination can be another option to reduce contrast media dose compared with total body weight-based dose determination since the volumes of blood and liver are not strictly proportional to total body weight. Therefore, we surmised that 50 keV images reconstructed with DLD algorithms with reducing iodine load by 30% based on LBW could produce the comparable image quality and lesion conspicuity compared with standard iodine-dose 120kVp images. In this single-center prospective, randomized clinical trial, we aimed to investigate the effectiveness of low-contrast dose CT using 50 keV and DLD technique compared with the standard contrast-dose protocol using model-based IR in patients at high risk of HCC.

Low CT contrast media dose calculated based on lean body weight and low monoenergetic images of dual-energy CT with deep learning-based denoising

Standard CT contrast media dose calculated based on total body weight and conventional images with full model-based iterative reconstruction

CT contrast media (iobitridol 350mgI/kg) is administrated at a dose of 450mgI/kg based on lean body weight.

CT contrast media (iobitridol 350mgI/kg) is administrated at a dose of 560mgI/kg based on total body weight.

qualitative scoring for focal lesion depiction on four-point scale (1: worst, 4: excellent, representative value is average score)

qualitative scoring for image noise on four-point scale (1: worst, 4: excellent, representative value is average score)

qualitative scoring for image contrast on four-point scale (1: worst, 4: excellent, representative value is average score)

qualitative scoring for image quality on four-point scale (1: worst, 4: excellent, representative value is average score)

assessment of focal liver lesion (HCC) on CT according to Liver Imaging Reporting and Data System (LI-RADS)

Inclusion Criteria: High risk group for developing HCC Scheduled contrast-enhanced CT for HCC diagnosis or surveillance Exclusion Criteria: not a high risk group for developing HCC body mass index is equal to or larger than 30 kg/m^2 suspected HCC > 5cm in diameter received locoregional treatment or surgery for HCC within 3 months congestive hepatopathy no venous access on forearm anticipated beam hardening artifact due to prosthesis relative/absolute contraindication of contrast-enhanced CT