Reply Ectopic Fat Deposition and Diabetes Mellitus

We thank Drs. Gaborit and Dutour for their interest in our paper (1). We acknowledge the lack of assessment of epicardial adipose tissue (EAT) volumes in healthy control subjects, which was due to concerns regarding unnecessary ionizing radiation exposure with coronary computed tomographic angiography. We agree that magnetic resonance imaging (MRI) is highly suitable for adipose tissue imaging. Dark blood prepared, T₁-weighted, multislice turbo spin-echo pulse sequence with a water suppression pre-pulse is an established MRI technique for reliable volumetric measurement of EAT volumes (2). Fat quantification on the basis of steady-state free precession cine imaging (i.e., the magnetic resonance images available to us) is unreliable in our experience. However, the addition of the established technique for assessment of EAT volumes would have extended scanning time for our participants to an unacceptable length. Acquiring multiparametric cardiovascular and liver magnetic resonance imaging, proton and phosphorus magnetic resonance spectroscopy protocol demanded a long scanning duration. Therefore, computed tomographic angiography, already part of the study protocol to rule out significant coronary artery stenosis, was used for EAT volume quantification, which allowed imaging of the coronary arteries and assessment of EAT volumes without additional scan time. This is a typical example of the challenge to find the balance between the desirable and the practical, regarding the amount of information we can obtain in a clinical MRI research study.

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