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![Example of hybrid SPECT/MRI cardiac imaging. Micro-SPECT/MRI image fusion showing healthy mouse whole-body contiguous coronal slices. [ 99m Tc]sestamibi SPECT tissue perfusion (heart) and tracer metabolic elimination routes (liver, gall bladder and digestive tract, kidneys) are represented in color superimposed on the MRI T1-weighted mouse anatomy in gray. Left ventricle wall perfusion and gall bladder are easily visible. Both sets of isotropic 3D images were acquired sequentially with the micro-SPECT (eXplore speCZT Vision 120) and the 1.5 T micro-MRI (OPTImouse 1.5; http://www.rs2d.com). Total acquisition time of both sets of images including the transfer of the animal in the imaging cell was 40 min.](profile/Christian-Goetz-7/publication/233752040/figure/fig3/AS:341484483170308@1458427653297/Example-of-hybrid-SPECT-MRI-cardiac-imaging-Micro-SPECT-MRI-image-fusion-showing-healthy.png)
Example of hybrid SPECT/MRI cardiac imaging. Micro-SPECT/MRI image fusion showing healthy mouse whole-body contiguous coronal slices. [ 99m Tc]sestamibi SPECT tissue perfusion (heart) and tracer metabolic elimination routes (liver, gall bladder and digestive tract, kidneys) are represented in color superimposed on the MRI T1-weighted mouse anatomy in gray. Left ventricle wall perfusion and gall bladder are easily visible. Both sets of isotropic 3D images were acquired sequentially with the micro-SPECT (eXplore speCZT Vision 120) and the 1.5 T micro-MRI (OPTImouse 1.5; http://www.rs2d.com). Total acquisition time of both sets of images including the transfer of the animal in the imaging cell was 40 min.
Source publication
This overview first summarizes the last decade of continuous developments and improvements in pre-clinical imaging methods that are now essential tools for in vivo evaluation of cardiac morphology and function in living mice, involving nuclear emission of labeled molecules (micro-PET and micro-SPECT) and electromagnetic wave interactions with biolo...
Context in source publication
Context 1
... at the end of both sets of image acquisition, rigid co-registration of SPECT and MRI images was obtained using the AMIDE open-source software (http://www.amide.sourceforge.net). The im- age fusion illustrated in Figure 6 allows a de- tailed and highly resolved three-dimensional anatomic location of the [ 99m Tc]sestamibi up- take in healthy living mouse tissues including the heart. ...
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Citations
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Background:
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Conclusions:
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Basic Protocol 1 : Setting up Köhler illumination for a brightfield microscope
Basic Protocol 2 : Aligning the fluorescence bulb and setting up Köhler illumination for a widefield fluorescence microscope
Basic Protocol 3 : Generic protocol for operating a confocal microscope
Background
Quantitative cardiac contractile function assessment is the primary indicator of disease progression and therapeutic efficacy in small animals. Operator dependency is a major challenge with commonly used echocardiography. Simultaneous assessment of cardiac perfusion and function in nuclear scans would reduce burden on the animal and facilitate longitudinal studies. We evaluated the accuracy of contractile function measurements obtained from electrocardiogram-gated nuclear perfusion imaging compared with anatomic imaging.
Methods and Results
In healthy C57Bl/6N mice (n = 11), 99mTc-sestamibi SPECT and ¹³N-ammonia PET underestimated left ventricular volumes (23 to 28%, P = 0.02) compared to matched anatomic images, though ejection fraction (LVEF) was comparable (%, SPECT: 73 ± 8 vs CMR: 72 ± 6, P = 0.1). At 1 week after myocardial infarction (n = 13), LV volumes were significantly lower in perfusion images compared to CMR and contrast CT (P = 0.003), and LVEF was modestly overestimated (%, SPECT: 37 ± 8, vs CMR: 27 ± 7, P = 0.003). Nuclear images exhibited good intra- and inter-reader agreement. Perfusion SPECT accurately calculated infarct size compared to histology (r = 0.95, P < 0.001).
Conclusions
Cardiac function can be calculated by gated nuclear perfusion imaging in healthy mice. After infarction, perfusion imaging overestimates LVEF, which should be considered for comparison to other modalities. Combined functional and infarct size analysis may optimize imaging protocols and reduce anaesthesia duration for longitudinal studies.
