PURPOSE: To evaluate whether single-phase dual-energy-CT-based attenuation measurements can reliably differentiate lipid-rich adrenal adenomas from malignant adrenal lesions.
MATERIALS AND METHODS: We retrospectively identified 51 patients with adrenal masses who had undergone contrast-enhanced dual-energy-CT (140/100 or 140/80 kVp). Virtual non-contrast and colour-coded iodine images were generated, allowing for measurement of pre- and post-contrast density on a single-phase acquisition. Adrenal adenoma was diagnosed if density on virtual non-contrast images was ≤ 10 HU. Clinical follow-up, true non-contrast CT, PET/CT, in- and opposed-phase MRI, and histopathology served as the standard of reference.
RESULTS: Based on the standard of reference, 46/57 (80.7 %) adrenal masses were characterised as adenomas or other benign lesions; 9 malignant lesions were detected. Based on a cutoff value of 10 HU, virtual non-contrast images allowed for correct identification of adrenal adenomas in 33 of 46 (71 %), whereas 13/46 (28 %) adrenal adenomas were lipid poor with a density ≥10 HU. Based on the threshold of 10 HU on the virtual non-contrast images, the sensitivity, specificity, and accuracy for detection of benign adrenal lesions was 73 %, 100 %, and 81 % respectively.
CONCLUSION: Virtual non-contrast images derived from dual-energy-CT allow for accurate characterisation of lipid-rich adrenal adenomas and can help to avoid additional follow-up imaging.
Written by:
Helck A, Hummel N, Meinel FG, Johnson T, Nikolaou K, Graser A. Are you the author?
Institute for Clinical Radiology, University of Munich, Grosshadern Campus, Marchioninistr. 15, 81377, Munich, Germany.
Reference: Eur Radiol. 2014 May 8. Epub ahead of print.
doi: 10.1007/s00330-014-3192-z
PubMed Abstract
PMID: 24804633
UroToday.com Adrenal and Kidney Conditions Section
