Volumetric low-tube-voltage CT imaging for evaluating hypervascular hepatocellular carcinoma; effects on radiation exposure, image quality, and diagnostic performance

Jpn J Radiol. 2013 Aug;31(8):521-9. doi: 10.1007/s11604-013-0217-5. Epub 2013 Jun 22.

Abstract

Objectives: To assess the value of hepatic arterial-phase (HAP) imaging with a low tube voltage (80 kVp), using non-helical, volumetric acquisition with a 320-detector-rows area-detector CT (ADCT) scanner for evaluating hypervascular hepatocellular carcinoma (HCC) compared with routine 120-kVp HAP imaging.

Methods: This study enrolled 128 patients with 148 HCCs. Seventy-six patients with 79 HCCs underwent HAP imaging with 80 kVp obtained using a 320-detector-rows ADCT scanner. The remaining 52 patients with 69 HCCs underwent routine HAP imaging with 120 kVp obtained by 64-slice helical acquisition. Image noise and tumor to liver contrast-to-noise ratio (CNR) of the two sets of images were compared. Three radiologists evaluated both sets of images using receiver operating characteristic analyses.

Results: Although there was a two-fold increase in the mean image noise with 80 kVp over that with 120 kVp (p < 0.001), no significant differences were observed in CNR among the two sets. The mean area under the curve (Az value) and the sensitivity for detecting HCC with 80 kVp (0.980, 78/79, respectively) were higher than that of 120 kVp (0.892, 55/69, respectively).

Conclusions: HAP imaging with 80 kVp obtained by an ADCT scanner significantly improves the diagnostic performance for evaluating hypervascular HCC.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Aged
  • Carcinoma, Hepatocellular / diagnostic imaging*
  • Contrast Media
  • Female
  • Humans
  • Iohexol
  • Liver / diagnostic imaging
  • Liver Neoplasms / diagnostic imaging*
  • Male
  • Middle Aged
  • Observer Variation
  • Prospective Studies
  • ROC Curve
  • Radiation Dosage*
  • Radiographic Image Enhancement / methods
  • Radiographic Image Interpretation, Computer-Assisted / methods
  • Reproducibility of Results
  • Sensitivity and Specificity
  • Tomography, Spiral Computed / methods
  • Tomography, X-Ray Computed / methods*

Substances

  • Contrast Media
  • Iohexol