Low-dose unenhanced CT for IV contrast bolus timing: is it reliable to assess hepatic steatosis?

Published

Journal Article

RATIONALE AND OBJECTIVES: To determine whether an unenhanced low-dose image acquired during automated contrast bolus timing can be used to assess hepatic steatosis. MATERIALS AND METHODS: Fifty subjects (29 male, 21 female; 26-92 years; mean body mass index (BMI; 26.9) with abdominal multiphasic computed tomography were included. Abdominal diameters and circumferences were derived from anteroposterior and lateral scout radiographs. Hepatic attenuation (HA) was measured on unenhanced low-dose images (120 kV; 40 mA; 0.5 seconds' rotation time) and corresponding unenhanced standard-dose images (120 kV, z-axis automatic tube current modulation, noise index 11.5). Noise estimates were measured in surrounding air. Pearson correlation was calculated between abdominal circumference and BMI. Mean HA assessed on low-dose images and standard-dose images was compared using a paired Student's t-test and Bland Altman plots. RESULTS: Abdominal circumference (mean, 142.8cm) correlated well with BMI (r = 0.83). No significant difference was found for HA on low-dose images (mean +57.7 HU) compared to HA on standard-dose images (+56.0 HU) (P = .077). Image noise (+11.5 HU) was significantly higher on low-dose images compared to image noise (+8.1 HU) on standard-dose images (P < .05). For HA mean difference comparing low- and standard-dose images was -1.7 HU (limits of agreement: -14.6, 11.2). CONCLUSION: In all subjects, hepatic attenuation can be correctly assessed on unenhanced low-dose images.

Full Text

Duke Authors

Cited Authors

  • Husarik, DB; Boll, DT; Nelson, RC; Merkle, EM

Published Date

  • July 2011

Published In

Volume / Issue

  • 18 / 7

Start / End Page

  • 822 - 827

PubMed ID

  • 21530330

Pubmed Central ID

  • 21530330

Electronic International Standard Serial Number (EISSN)

  • 1878-4046

International Standard Serial Number (ISSN)

  • 1076-6332

Digital Object Identifier (DOI)

  • 10.1016/j.acra.2011.02.013

Language

  • eng