Background
Dual-energy CT (DECT) permits the simultaneous operation of two different kV levels, providing a potential method toward the assessment of diffuse myocardial fibrosis. The
Conclusions
DECT-ECV correlated well with both SECT-ECV and histology, showing the feasibility of DECT in evaluating doxorubicin-induced diffuse myocardial interstitial fibrosis.
Methods
Myocardial ECV was quantified in fifteen dogs using DECT and dynamic equilibrium SECT before and after doxorubicin administration. Cardiac magnetic resonance imaging (CMRI) was used to assess myocardial function. The histological collagen volume fraction (CVF) was calculated as the gold standard. The Bland-Altman analysis was performed to compare the agreement between DECT-ECV and SECT-ECV. The association among ECV values derived from DECT and SECT, CVF, and left ventricular ejection fraction (LVEF) were determined by correlation analysis. The variations of these values were evaluated using repeated ANOVA.
Results
The DECT- and SECT-ECV were increased with the elongation of modeling time (pre-modeling vs. 16-week models vs. 24-week models: DECT-ECV 24.1%±1.1%, 35.1%±1.3% and 37.6%±1.4%; SECT-ECV 22.9%±0.8%, 33.6%±1.2% and 36.3%±1.0%; n=30 in per-subject analysis, all P<0.05). Both ECV values of DECT and SECT correlated well with the histological CVF results (R=0.935 and 0.952 for the DECT-ECV and SECT-ECV; all P<0.001; n=13). Bland-Altman plots showed no significant differences between DECT- and SECT-ECV. Conclusions: DECT-ECV correlated well with both SECT-ECV and histology, showing the feasibility of DECT in evaluating doxorubicin-induced diffuse myocardial interstitial fibrosis.