European Journal of Radiology 74 (2010) e149–e153 Contents lists available at ScienceDirect European Journal of Radiology journal homepage: www.elsevier.com/locate/ejrad Comparison of different quantification methods of late gadolinium enhancement in patients with hypertrophic cardiomyopathy Mateusz Spiewak a,∗ , Lukasz A. Malek a,1 , Jolanta Misko b,2 , Lidia Chojnowska c,1 , Barbara Milosz b,2 , Mariusz Klopotowski c,1 , Joanna Petryka a,1 , Maciej Dabrowski c,1 , Cezary Kepka a,1 , Witold Ruzyllo c,3 a First Department of Coronary Artery Disease, Magnetic Resonance Unit, Institute of Cardiology, ul. Alpejska 42, 04-628 Warsaw, Poland b Magnetic Resonance Unit, Institute of Cardiology, ul. Alpejska 42, 04-628 Warsaw, Poland c First Department of Coronary Artery Disease, Institute of Cardiology, ul. Alpejska 42, 04-628 Warsaw, Poland article info Article history: Received 26 April 2009 Received in revised form 19 May 2009 Accepted 20 May 2009 Keywords: Late gadolinium enhancement Fibrosis Quantification Hypertrophic cardiomyopathy Cardiac magnetic resonance abstract Aim: There is no consensus regarding the technique of quantification of late gadolinium enhancement (LGE). The aim of the study was to compare different methods of LGE quantification in patients with hypertrophic cardiomyopathy (HCM). Methods: Cardiac magnetic resonance was performed in 33 patients with HCM. First, LGE was quantified by visual assessment by the team of experienced readers and compared with different thresholding tech- niques: from 1SD to 6SD above mean signal intensity (SI) of remote myocardium, above 50% of maximal SI of the enhanced area (full-width at half maximum, FWHM) and above peak SI of remote myocardium. Results: LGE was present in 25 (78%) of patients. The median mass of LGE varied greatly depending on the quantification method used and was highest with the utilization of 1SD threshold [75.5g, interquartile range (IQR): 63.3–112.3 g] and lowest for FWHM method (8.4 g, IQR: 4.3–13.3 g). There was no difference in mass of LGE as assessed with 6SD threshold and FWHM when compared to visual assessment (p = 0.19 and p = 0.1, respectively); all other thresholding techniques provided significant differences in the median LGE size when compared to visual analysis. Results for all thresholds, except FWHM were significantly correlated with visual assessment with the strongest correlation for 6SD (rho = 0.956, p < 0.0001). Conclusions: LGE quantification with the use of a threshold of 6SD above the mean SI of the remote myocardium provided the best agreement with visual assessment in patients with HCM. © 2009 Elsevier Ireland Ltd. All rights reserved. 1. Introduction Late gadolinium enhancement (LGE) cardiac magnetic reso- nance (CMR) is a robust technique for detection of fibrosis in patients with hypertrophic cardiomyopathy (HCM) [1,2]. It was demonstrated that LGE is associated with frequency and occur- rence of arrhythmias in this population [3]. However, there is no consensus regarding the technique of LGE quantification. Sev- eral CMR centers use different signal intensity (SI) thresholds as ∗ Corresponding author. Tel.: +48 22 3434272; fax: +48 22 6133819. E-mail addresses: mspiewak@ikard.pl (M. Spiewak), lmalek@ikard.pl (L.A. Malek), jmisko@wp.pl (J. Misko), lchojnowska@ikard.pl (L. Chojnowska), barbara-milosz@tlen.pl (B. Milosz), mklopotowski@hotmail.com (M. Klopotowski), joannapetryka@hotmail.com (J. Petryka), macidabro@yahoo.com (M. Dabrowski), ckepka@ikard.pl (C. Kepka), w.ruzyllo@ikard.pl (W. Ruzyllo). 1 Tel.: +48 22 3434272; fax: +48 22 6133819. 2 Tel.: +48 22 3434657; fax: +48 22 6133819. 3 Tel.: +48 22 3434450; fax: +48 22 3434500. well as visual assessment for LGE analysis in patients with HCM [1,3–8]. The most common method is thresholding with the use of SI cut-off values of 2 [1,5–7] or 6 [3,8] standard deviations (SDs) above the remote non-injured myocardium. In the case of myocar- dial infarction also other techniques have been described with the use of a definition of hyperenhancement as a region with SI above peak remote myocardium (PRM) [9] or above 50% of the SI of the hyperenhanced area (full-width at half maximum, FWHM) [10]. However, LGE quantification in patients with HCM is based on observations in patients with coronary artery disease and myocar- dial infarction. Little is known about the differences in thresholding techniques in non-ischemic cardiomyopathies such as HCM. Data from studies in coronary artery disease showed wide variation in LGE extent measured by different techniques with significant over- estimation of 2SD above mean SI of a remote myocardium method over visual analysis [11]. The aim of the study was to compare different methods of LGE quantification in patients with HCM. 0720-048X/$ – see front matter © 2009 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.ejrad.2009.05.035