Single-Acquisition Triple-Bolus Dual-Energy CT Protocol for Comprehensive Evaluation of Renal Masses: A Single-Center Randomized Noninferiority Trial.

Abstract

The primary objective of this study was to compare triple-bolus dual-energy CT (DECT) against standard triple-phase MDCT in terms of appropriateness of patient treatment. One hundred twenty-four patients with suspected renal masses seen at ultrasound were randomized into triple-bolus DECT and triple-phase MDCT groups. Patients in the triple-bolus DECT group underwent synchronous corticomedullary nephrographic delayed-phase triple-bolus DECT. In the triple-phase MDCT group, single-energy triple-phase scans were acquired after an unenhanced scan. The primary outcome was appropriateness of treatment received at 1 year. The predefined noninferiority limit was 10%. Histopathologic analysis or follow-up confirmed the benign or malignant nature of the masses. Diagnostic accuracy to differentiate benign from malignant masses was calculated. Size-specific dose estimates were compared. After excluding six patients, 118 patients were analyzed (62 triple-bolus DECT; 56 triple-phase MDCT). Treatment appropriateness was not significantly different (p = 0.9397) between the two groups (61/62 [98.39%; 95% CI, 95.26-101.52%] for triple-bolus DECT vs 55/56 [98.21%; 95% CI, 94.74-101.68%] for triple-phase MDCT). The absolute difference was 0.18% (95% CI, -4.48% to 4.84%). Both techniques had similar diagnostic accuracy (sensitivity, 98.25% vs 96.67%; specificity, 98.17% vs 97.97%). The mean (± SD) size-specific dose estimate was significantly lower for triple-bolus DECT than for triple-phase MDCT (19.02 ± 4.07 vs 57.04 ± 15.17 mGy; p < 0.0001). Single-acquisition triple-bolus DECT is noninferior to triple-phase MDCT, with similar diagnostic accuracy but delivering significantly less radiation.