PURPOSE: To realize objective @entity2318 assessment, this study aimed to develop a fully automatic method to segment the left atrium (LA) and pulmonary veins (PV) from late @entity2287 -enhanced (LGE) magnetic resonance imaging (MRI). The extent and distribution of @entity2318 , visualized by LGE-MRI, provides important information for clinical treatment of @entity955 ( @entity955 ) @entity1 . MATERIALS AND METHODS: Forty-six @entity955 @entity1 (age 62    8, 14 female) who underwent cardiac MRI prior to RF ablation were included. A contrast-enhanced MR angiography (MRA) sequence was acquired for anatomy assessment followed by an LGE sequence for LA scar assessment. A fully automatic segmentation method was proposed consisting of two stages: 1) global segmentation by multiatlas registration; and 2) local refinement by 3D level-set. These automatic segmentation results were compared with manual segmentation. RESULTS: The LA and PVs were automatically segmented in all subjects. Compared with manual segmentation, the method yielded a surface-to-surface distance of 1.49    0.65 mm in the LA region when using both MRA and LGE, and 1.80    0.93 mm when using LGE alone (P < 0.05). In the PV regions, the distance was 2.13    0.67 mm and 2.46    1.81 mm (P < 0.05), respectively. The difference between automatic and manual segmentation was comparable to the interobserver difference (P = 0.8 in LA region and P = 0.7 in PV region). CONCLUSION: We developed a fully automatic method for LA and PV segmentation from LGE-MRI, with comparable performance to a @entity1 observer. Inclusion of an MRA sequence further improves the segmentation accuracy. The method leads to automatic generation of a @entity1 -specific model, and potentially enables objective @entity2318 assessment for @entity955 @entity1 . J. Magn. Reson. Imaging 2016.

Fully automatic segmentation of left atrium and pulmonary veins in late XXXX -enhanced MRI: Towards objective @entity2318 assessment.

@entity1 :: ('9606', 'Species') :: ['human', 'patients', 'patient'] @entity2318 :: ('MESH:D002921', 'Disease') :: ['atrial scar'] @entity2287 :: ('MESH:D005682', 'Chemical') :: ['gadolinium'] @entity955 :: ('MESH:D001281', 'Disease') :: ['atrial fibrillation', 'AF']
@entity2287 :: (MESH:D005682,Chemical) :: ['gadolinium']
