Fig. 6

Bland–Altman and scatter plots comparing maximum aortic measurements and disease progression between CTA and CMRA. Bland–Altman plots (a–c) show good agreement between measurements of maximum aortic diameters obtained by CTA and CMRA both at baseline (mean difference: − 0.21 mm; a) and at 1-year follow up (mean difference: − 0.19 mm; b). The mean of differences for disease progression was 0.03 mm between the techniques (c). Scatter plots (d–f) demonstrate excellent agreement between measurements on CTA and CMRA of the baseline (d) and follow up (e) maximum aortic diameters with ICC values of 0.99. The difference between the baseline and follow up measurements, representing disease progression, showed an ICC value of 0.91 (f). Note, that both the ascending and descending sections of the aorta showed dilatation in some patients, therefore the number of data points displayed (n = 23) is higher than the number of subjects included (n = 15). Red markers represent the ascending, while green markers show the descending aorta. CTA computed tomography angiography, CMRA cardiovascular magnetic resonance angiography, ICC intra-class correlation coefficient