Myocardial Microinfarct Measurments on MRI, MDCT and Histopathology

Maythem Saeed¹, Sammir Sullivan¹, Loi Do¹, Mark Wilson¹

The objectives were to use DE-MRI and DE-MDCT imaging and light microscopy to determine the relationship and the limits of agreement for measuring myocardial microinfarct. Pigs (n=14) received either 16mm³ or 32mm³ of 40-120m microemboli. Clinical MRI and MDCT scanners were used 3 days after microembolization. Gd-DTPA and iohexol were used to enhance microinfarct. MRI and MDCT imaging showed systematic underestimation of microinfarct size and area at risk compared with histopathology, which should be considered in evaluating microinfarct using these modalities and may be related to differences in spatial resolution, light microscopy, mismatch between slices and volume averaging effect.