An ultra high resolution ECG-gated myocardial imaging system for small animals

Standard radionuclide imaging systems are of limited use due to their inability to resolve structures in small animals that represent an increasingly important model for the study of cardiovascular disease. The authors are developing an imaging system incorporating a scintillation camera with a pinhole collimator to acquire cardiac gated images of the mouse heart. Through a simulation study, the authors found that the effective diameter of the pinhole was unaffected by the scatter component of photon penetration through the pinhole insert. The authors have performed a myocardial perfusion study with 0.68 FWHM resolution on a normal 25 gram mouse gated at over 400 beats per minute. The authors have demonstrated that it is possible to obtain cardiac-gated, myocardial perfusion images of mice at submillimeter spatial resolution.