Wolfram Machann MD, Presenter: Nothing to Disclose

Sabrina Koeppe, Abstract Co-Author: Nothing to Disclose

Frank Breunig, Abstract Co-Author: Nothing to Disclose

Christoph Wanner, Abstract Co-Author: Nothing to Disclose

Herbert Koestler PhD, Abstract Co-Author: Nothing to Disclose

Dietbert Hahn MD, Abstract Co-Author: Nothing to Disclose

Meinrad Johannes Beer MD, Abstract Co-Author: Nothing to Disclose

et al, Abstract Co-Author: Nothing to Disclose

et al, Abstract Co-Author: Nothing to Disclose

Late enhancement (LE) is often used to detect myocardial fibrosis none invasively in MR-Imaging. However LE often has an irregular pattern, which makes quantification difficult. Until now the reproducibility of measuring LE was only determined for large myocardial infarctions. Purpose of this study was, to investigate intra- and interobsever variability of LE-measurements in patients with Fabry disease at baseline and after 12 months of enzyme replacement therapy.

We examined 14 patients at baseline and 10 at follow up. We used an inversion revovery gradientecho sequence (TR 7.5 ms; TE 3.4 ms; flipangle 25°, TI determined individually) on a 1.5T MR-Scanner 10 to 15 minutes after injection of 0.2 mmol Gadolinium per kg bodyweight. The borders of the enhanced areas were traced manually using ARGUS. The mass of LE was computed by summing the amount of every shortaxis slice. Variabilities wer determined on the basis of the results by one (intra-) or two experienced and blinded radiologists using the bland altman analysis.

Volumes at baseline were 4.2±4.2ml or 2.1±1.7% of left ventricular mass (mean 207±70g, range 111-346g). At follow up LE volumes increased (p<0.05) to 6.4±6.0ml or 3.5±3.0% of left ventricular mass (mean 194±60g; range 140-308g). 95% confidence intervals for intraobserver variability were -0,6 to 1,4 at baseline and -0,6 to 2,0 at follow up. 95% confidence intervals for interobserver variability were -0,3 to 0,7 at baseline and -0,4 to 0,4 at follow up.

Manual planimetry of LE shows both a very low intra- and interobserver variability. LE can be used as a follow up parameter for the determination of the amount of myocardial fibrosis in patients with cardiomyopathies.

Planimetry of LE in cardiomyopathies is an important parameter to determine the course of disease exactly and a tool to define a starting point of a specific therapy like an enzyme replacement.

Machann, W, Koeppe, S, Breunig, F, Wanner, C, Koestler, H, Hahn, D, Beer, M, et al, , et al, , Quantification of Late Enhancement: Intra- and Interobserver Variability.  Radiological Society of North America 2007 Scientific Assembly and Annual Meeting, November 25 - November 30, 2007 ,Chicago IL. http://archive.rsna.org/2007/5010150.html