Fig. 5

Correlation of native contrast T1w imaging to histology for RF ablation lesions (green arrows). a In vivo T1w imaging, b ex vivo T1w imaging with reduced partial volume effects, and c corresponding gross photography demonstrate that T1 enhancement correlates better with the pale inner core of the lesion rather than the darker outer rim of the lesion (c, red arrows). d Histology of this lesion shows the two distinct zones of necrosis indicated by shades of deeper purple trichrome staining. The dashed rectangle inset is expanded in (e) to focus on the lesion boundary. Solid rectangle insets are expanded to show the (f) inner core of coagulation necrosis, and (g) outer rim of mixed coagulation necrosis and thin outer band of contraction band necrosis as well as significant numbers of extravasated red blood cells (yellow arrows), before transitioning to (h) normal myocardium. The outer rim of RF ablation lesions (g) does not appear to result in T1-enhancement