Fig. 4

Comparison of chemoablation and RF ablation lesion signal-to-noise ratios (SNR, a) and contrast-to-noise ratio (CNR, b) obtained with 3D native contrast T1w imaging with 2RR triggering acutely on Day 0 after ablation. SNR values are normalized to the chemoablation SNR denoted by the asterisks. CNRs values are all normalized to the lesion core-myocardium CNR (*) to facilitate comparison across categories (right scale). Chemoablation lesion cores had significantly higher mean (× 1.8), median, and peak SNR than RF ablation lesion cores, resulting in improved lesion conspicuity. Chemoablation also demonstrated higher CNR with respect to myocardium (× 3.8), lesion external periphery (× 2.8), and the blood pool. RF ablation lesions had a hypointense rim, likely due to surrounding edema, that resulted in 38% higher lesion-periphery CNR than lesion-myocardium CNR. This difference was not noted for chemoablation, suggesting less surrounding edema for these lesions. Significant differences are denoted by † (Student’s t-test, paired, Bonferroni correction). As a reference, blood pool-myocardium CNR was 0.18 ± 0.10 indicating blood pool signal suppression through inversion-recovery worked well. Hence, chemoablation demonstrated significant improvement in SNR and CNRs