Assessment of aortic diameter in Marfan patients: intraindividual comparison of 3D-Dixon and 2D-SSFP magnetic resonance imaging

Figures

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  Fig. 1. Comparison of 3D-Dixon and 2D-SSFP MR-imaging of the thoracic aorta with indicated measurement levels. Para-sagittal 3D-Dixon (a) and 2D-SSFP MR-imaging (b) in a 36-year-old woman with confirmed Marfan syndrome. White lines indicate the five aortic measurement levels for diameter as well as image quality and artifact estimation: (1) sinuses of Valsalva, (2) sinotubular junction, (3) ascending aorta, (4) mid aortic arch, and (5) descending aorta

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  Fig. 2. Intra- and interobserver agreement of 3D-Dixon and 2D-SSFP diameter measurements at the sinuses of Valsalva. Bland-Altman analyses of intraobserver (a, b) and interobserver agreement (c, d) demonstrate significantly greater variances of 3D-Dixon as compared to 2D-SSFP measurements (p < 0.001 and p = 0.02, respectively). Dotted lines indicate limits of agreement and middle solid line indicates the mean bias of diameter measurements

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  Fig. 3. Bland-Altman comparison of 3D-Dixon vs. 2D-SSFP diameter measurements at the sinuses of Valsalva. The plot reveals a non-significant mean difference of 0.1 ± 2.3 mm between 3D-Dixon and 2D-SSFP-derived measurements (p = 0.53). Dotted lines indicate limits of agreement and the middle solid line indicates mean bias of diameter measurements

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  Fig. 4. Bland-Altman analyses of 3D-Dixon and 2D-SSFP measurements in comparison to echocardiographic measurements at the sinuses of Valsalva. Bland-Altman plots demonstrate statistically significant mean biases of 1.0 mm (limits of agreement: −4.08 to 6.11 mm) for 3D-Dixon (a) and of 1.1 mm (limits of agreement: −3.97 to 6.23 mm) for 2D-SSFP measurements (b) when compared to echocardiographic diameter measurements (p = 0.010 and p = 0.005, respectively). Dotted lines indicate limits of agreement and the middle solid line indicates mean bias of diameter measurements

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  Fig. 5. Comparison of image quality and image artifacts of respiratory-gated 3D-Dixon and breath-hold 2D-SSFP imaging. Parasagittal respiratory-gated 3D-Dixon imaging (a) resulted in a blurred delineation of the sinuses of Valsalva (arrows), while breath-hold 2D-SSFP imaging (b) resulted in sharper delineation of the sinuses of Valsalva (arrows) in this 43-year-old male patient with confirmed Marfan syndrome. Both readers rated the image quality at the sinuses of Valsalva as an average of 3.5 points (= good) for 3D-Dixon and 4 points (= excellent) for 2D-SSFP. Both readers rated the image artifacts as an average of 4 points (excellent) for 3D-Dixon and 3.5 points (= good) for 2D-SSFP. Both 3D-Dixon-derived and 2D-SSFP-derived measurements resulted in a maximum aortic diameter of 34 mm at the level of the sinuses of Valsalva

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  Fig. 6. Qualitative analyses of image quality and image artifacts of respiratory-gated 3D-Dixon and breath-hold 2D-SSFP imaging. Results of image quality and artifact rating are reported for 2D-SSFP (black circles) and 3D-Dixon (white diamonds) as estimated marginal means with corresponding 95% confidence intervals (95%-CIs) and cumulated estimated probabilities. Four-point scales were used for image quality rating (1 = poor, 4 = excellent) and artifact rating (1 = severe, 4 = none)