showing 7 related works from this author
Preferential patterns of myocardial iron overload by multislice multiecho T2* CMR in thalassemia major patients.
2010
T*(2) multislice multiecho cardiac MR allows quantification of the segmental distribution of myocardial iron overload. This study aimed to determine if there were preferential patterns of myocardial iron overload in thalassemia major. Five hundred twenty-three thalassemia major patients underwent cardiac MR. Three short-axis views of the left ventricle were acquired and analyzed using a 16-segment standardized model. The T*(2) value on each segment was calculated, as well as the global value. Four main circumferential regions (anterior, septal, inferior, and lateral) were defined. Significant segmental variability was found in the 229 patients with significant myocardial iron overload (glob…
Non-compact myocardium assessment by cardiac magnetic resonance: dependence on image analysis method
2018
To compare image analysis methods for the assessment of left ventricle non-compaction from cardiac magnetic resonance (CMR) imaging. CMR images were analyzed in 20 patients and 10 normal subjects. A reference model of the MR signal was introduced and validated based on image data. Non-compact (NC) myocardium size and distribution were assessed by tracing a single, continuous contour delimiting trabeculated region (Jacquier) or by one-by-one selection of trabeculae (Grothoff). The global non-compact/compact (NC/C) ratio, the NC mass, and the segmental NC/C ratio were assessed. Results were compared with the reference model. A significant difference between Grothoff and Jacquier approaches in…
Improved T2* assessment in liver iron overload by magnetic resonance imaging.
2009
In the clinical MRI practice, it is common to assess liver iron overload by T2* multi-echo gradient-echo images. However, there is no full consensus about the best image analysis approach for the T2* measurements. The currently used methods involve manual drawing of a region of interest (ROI) within MR images of the liver. Evaluation of a representative liver T2* value is done by fitting an appropriate model to the signal decay within the ROIs vs. the echo time. The resulting T2* value may depend on both ROI placement and choice of the signal decay model. The aim of this study was to understand how the choice of the analysis methodology may affect the accuracy of T2* measurements. A softwar…
Multislice multiecho T2* cardiac magnetic resonance for the detection of heterogeneous myocardial iron distribution in thalassaemia patients
2009
The present study investigated myocardial T2* heterogeneity in thalassaemia major (TM) patients by cardiac magnetic resonance (CMR), to determine whether is related to inhomogeneous iron overload distribution. A total of 230 TM patients consecutively referred to our laboratory were studied retrospectively. Three short-axis views (basal, medium and apical) of the left ventricle (LV) were obtained by multislice multiecho T2* CMR. T2* segmental distribution was mapped on a 16-segment LV model. The level of heterogeneity of the T2* segmental distribution, evaluated by the coefficient of variation (CoV), was compared with that of a surrogate data set, to determine whether the inhomogeneous segme…
Multislice multiecho T2* cardiovascular magnetic resonance for detection of the heterogeneous distribution of myocardial iron overload.
2006
Purpose To assess the tissue iron concentration of the left ventricle (LV) using a multislice, multiecho T2* MR technique and a segmental analysis. Materials and Methods T2* multiecho MRI was performed in 53 thalassemia major patients. Three short-axis views of the LV were obtained and analyzed with custom-written software. The myocardium was automatically segmented into 12 segments. The T2* value on each segment as well as the global T2* value were calculated. Cine dynamic images were also obtained to evaluate biventricular function parameters by quantitative analysis. Results For the T2* global value, the coefficient of variation (CoV) for intra-/interobserver and interstudy reproducibili…
Standardized T2* map of normal human heart in vivo to correct T2* segmental artefacts.
2007
A segmental, multislice, multi-echo T2* MRI approach could be useful in heart iron-overloaded patients to account for heterogeneous iron distribution, demonstrated by histological studies. However, segmental T2* assessment in heart can be affected by the presence of geometrical and susceptibility artefacts, which can act on different segments in different ways. The aim of this study was to assess T2* value distribution in the left ventricle and to develop a correction procedure to compensate for artefactual variations in segmental analysis. MRI was performed in four groups of 22 subjects each: healthy subjects (I), controls (II) (thalassemia intermedia patients without iron overload), thala…
Influence of myocardial fibrosis and blood oxygenation on heart T2* values in thalassemia patients
2009
Purpose To determine whether T2* measurements quantifying myocardial iron overload in thalassemia patients are influenced by myocardial fibrosis and blood oxygenation. Materials and Methods Multislice multiecho T2* was performed in 94 thalassemia patients in order to quantify myocardial iron overload. The left ventricle was automatically segmented into a 16-segment standardized heart model, and the T2* value on each segment as well as the global T2* were calculated. Delayed enhanced cardiovascular magnetic resonance (DE-CMR) images were obtained to detect myocardial fibrosis. The blood oxygenation was assessed by the noninvasive measurement of partial pressure of oxygen (pO2). Results Myoca…