A Novel Skeleton Based Quantification and 3-D Volumetric Visualization of Left Atrium Fibrosis Using Late Gadolinium Enhancement Magnetic Resonance Imaging

Abstract

This work presents the results of a new tool for 3-D segmentation, quantification and visualization of cardiac left atrium fibrosis, based on late gadolinium enhancement magnetic resonance imaging (LGE-MRI), for stratifying patients with atrial fibrillation (AF) that are candidates for radio-frequency catheter ablation. In this study 10 consecutive patients suffering AF with different grades of atrial fibrosis were considered. LGE-MRI and magnetic resonance angiography (MRA) images were used to detect and quantify fibrosis of the left atrium using a threshold and 2-D skeleton based approach. Quantification and 3-D volumetric views of atrial fibrosis were compared with quantification and 3-D bipolar voltage maps measured with an electro-anatomical mapping (EAM) system, the clinical reference standard technique for atrial substrate characterization. Segmentation and quantification of fibrosis areas proved to be clinically reliable among all different fibrosis stages. The proposed tool obtains discrepancies in fibrosis quantification less than 4% from EAM results and yields accurate 3-D volumetric views of fibrosis of left atrium. The novel 3-D visualization and quantification tool based on LGE-MRI allows detection of cardiac left atrium fibrosis areas. This noninvasive method provides a clinical alternative to EAM systems for quantification and localization of atrial fibrosis.

A fully automatic deep learning method for atrial scarring segmentation from late gadolinium-enhanced MRI images

“…Transverse navigator-gated 3D LGE MRI [6], [7], [16] was performed using an inversion prepared segmented gradient echo sequence (TE/TR 2.2ms/5.2ms) 15 minutes after gadolinium (Gd) administration when a transient steady-state of Gd wash-in and wash-out of normal myocardium had been reached [17]. LGE MRI images were scanned with a field-of-view 380×380mm 2 and reconstructed to 60-68 slices at 0.75×0.75×2mm 3 . The LA and PVs geometry would ideally be segmented directly using 3D LGE MRI dataset.…”

“…In this study, instead of using un-gated MRA, a respiratory and cardiac gated 3D Roadmap image, i.e., using a balanced steady state free precession sequence (TE/TR 1ms/2.3ms), has been acquired for each patient to resolve the cardiac anatomy. The Roadmap data were acquired with a field-of-view 380×380mm 2 and reconstructed to 160 slices at 0.8×0.8×1.6mm 3 . Both 3D LGE MRI and Roadmap data were acquired during free-breathing using a crossed-pairs navigator positioned over the dome of the right hemi-diaphragm with navigator acceptance window size of 5mm and CLAWS respiratory motion control [18].…”

“…Moreover, LA fibrosis may be arrhythmogenic that causes more aggressive symptoms and makes difficulties in the management of AF [1]. Minimally invasive catheter ablation (CA) using radio-frequency energy has become one of the most common treatments for AF patients refractory to drug treatment [2]. CA aims to electrically isolate the pulmonary veins (PVs) from the left atrial (LA) body because previous studies show that ectopic beats from the PVs can frequently trigger the AF [3].…”

“…For the LA and PVs geometry, most previous studies have relied on manual delineation [2], [7]- [10]. Knowles et al [11] used a semi-automatic thresholding and region growing method to extract the LA and PVs anatomy.…”

Topology Preserving Thinning of Cell Complexes

“…Furthermore, many computer-aided diagnostic tools rely on skeletons. For example, skeletons have been used to identify blood vessels stenoses [23]- [25], tracheal stenoses [26], polyps and cancer in colon [27] and left atrium fibrosis [28].…”