Dual-energy CT for differential diagnosis of adrenal lesions
Description
Evaluation of the diagnostic utility of DECT in differentiating adrenal lesions. We present DECT parameters for arterial, venous and delayed phases
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Steps to reproduce
DECT examinations were performed using a Revolution CT scanner (GE Healthcare, USA) with rapid kVp switching (alternating 80/140 kVp) during a single rotation. Tube currents were set to 200 mA for non-contrast scans, 485 mA for arterial/venous phases, and 280 mA for the delayed phase. All acquisitions used helical scan mode with the following parameters: 128 × 0.625 mm collimation, 0.625/1.25 mm slice thickness, 1.25 mm interslice spacing, and a pitch of 0.992. Contrast administration utilized a MEDRAD Stellant CT Injection System (Bayer, Germany) at 3.5–4 mL/s. Arterial and venous phases were triggered at 10 seconds and 30 seconds post-bolus tracking threshold (120 HU in the aorta at diaphragmatic level). The delayed phase was acquired 10–15 minutes post-contrast.DECT datasets were processed using special software (AW Server 3.2 Ext 6.0, GE Healthcare, USA). Quantitative analysis of attenuation values and tissue characteristics was performed using VMIs at (40, 70, 80 keV) and MD maps (water-iodine, fat-iodine, water-fat). DECT parameter quantification was performed by radiologists with 2-6 years of experience in cross-sectional abdominal imaging. Analysis was blinded to clinical data to prevent bias. A senior radiologist with 15 years of experience independently validated all calculations. Mean, maximum, and minimum attenuation values on monochromatic images (40, 70, 80 keV), along with material concentrations from MD maps, were measured using manually placed circular regions of interest. Regions of interest were positioned within the largest solid area of the adrenal lesion at its maximum cross-section, excluding necrosis/cysts, calcifications, normal parenchyma, periadrenal fat and vascular structures. Identical DECT parameter measurements were obtained from contralateral normal adrenal tissue using the same methodology. Arterial, venous, and delayed phase DECT acquisitions were analyzed according to the standardized protocol.
Institutions
- Endokrinologicheskii nauchnyi tsentr