Accurate noninvasive measurement of infarct size in mice with high-resolution PET.
Reliable, repeatable, and time-efficient noninvasive measurement of infarct size in mice with PET would benefit studies aimed at the exploration of biochemical and functional changes associated with acute myocardial infarction (MI). PET with the radioactively labeled glucose derivative (18)F-FDG is used in humans to distinguish between viable but dysfunctional and nonviable myocardium. In this study, the feasibility, accuracy, and time efficiency of (18)F-FDG PET for quantification of infarct size in mice using a high-resolution animal PET device was evaluated in comparison with histomorphometry.


METHODS
Mice were subjected to surgery with permanent ligation of the left anterior descending artery. PET was performed before and 7 d after surgery. The infarct size was determined from the PET studies using both manual and automated delineation. The second PET scan was followed by histomorphometric analysis.


RESULTS
An excellent correlation between PET and histomorphometry was found for both manual (R = 0.98) and automated (R = 0.98) delineation, with linear regression curves close to unity (manual: y = 1.10x - 0.01; automated: y = 1.12x - 0.02). Automated analysis required <1 min per study.


CONCLUSIONS
The measurement of infarct size in mice with (18)F-FDG PET is feasible and highly accurate. This noninvasive methodology permits unique longitudinal studies of biochemical parameters in mice and facilitates studies that aim to assess the effect of surgical and pharmacologic intervention after acute MI.
Stegger
Lars
L
Department of Nuclear Medicine, University Hospital Münster, Münster, Germany. stegger@uni-muenster.de
Hoffmeier
Anne-Nadine
AN
Schäfers
Klaus P
KP
Hermann
Sven
S
Schober
Otmar
O
Schäfers
Michael A
MA
Theilmeier
Gregor
G
D000465:Algorithms; D000818:Animals; D001331:Automation; D004195:Disease Models, Animal; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D051379:Mice; D009203:Myocardial Infarction / Q000175:diagnosis* / Q000473:pathology*; D009206:Myocardium / Q000473:pathology; D049268:Positron-Emission Tomography / Q000379:methods*; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results
D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18