Keywords:
MR, Cardiac, Anatomy, Computer Applications-3D, Contrast agent-intravenous, Image registration, Pathology
Authors:
S. K. Ternovoy, O. Stukalova, O. Aparina, D. Parkhomenko, N. Mironova; Moscow/RU
Methods and Materials
Materials and methods: 23 HV and 53 AFp during sinus rhythm underwent CMR on 1.5 T clinical scanner.
LGE MRI (voxel size reconstructed to 0,625x0,625x2,5mm) was performed 15min after gadoversetamide injection.
From LGE MRI images LA walls were segmented semiautomaticaly using standardized protocol for artifact exclusion.
For LA LGE quantification new indicators were developed and calculated.
They were mean atrial wall intensity to mean blood intensity ratio (diffuse intensity ratio,
DIR) and maximum atrial wall intensity to mean blood pool intensity ratio (maximal intensity ratio,
MIR).
LAF quantification was performed using original threshold-based algorithm.
Atrial wall pixel was defined as fibrotic if it’s signal intensity (SI) ratio to mean blood pool SI was more than MIR of HV.
Sum of all fibrotic pixels in all layers of atrial wall divided by sum of all atrial wall pixels represented fibrosis extent.