Related Experiment Video
Updated: Jun 3, 2026
In Vivo Quantitative Assessment of Myocardial Structure, Function, Perfusion and Viability Using Cardiac Micro-computed Tomography
Published on: February 16, 2016
Photoacoustic tomography of ex vivo mouse hearts with myocardial infarction
Markus Holotta1, Harald Grossauer, Christian Kremser
1Innsbruck Medical University, Department of Radiology, Innsbruck, Austria. markus.holotta@i-med.ac.at
Abstract:
In the present study, we evaluated the applicability of ex vivo photoacoustic imaging (PAI) on small animal organs. We used photoacoustic tomography (PAT) to visualize infarcted areas within murine hearts and compared these data to other imaging techniques [magnetic resonance imaging (MRI), micro-computed tomography] and histological slices. In order to induce ischemia, an in vivo ligation of the left anterior descending artery was performed on nine wild-type mice. After varying survival periods, the hearts were excised and fixed in formaldehyde. Samples were illuminated with nanosecond laser pulses delivered by a Nd:YAG pumped optical parametric oscillator. Ultrasound detection was achieved using a Mach-Zehnder interferometer (MZI) working as an integrating line detector. The voxel data were computed using a Fourier-domain based reconstruction algorithm, followed by inverse Radon transforms. The results clearly showed the capability of PAI to visualize myocardial infarction and to produce three-dimensional images with a spatial resolution of approximately 120 μm. Regions of affected muscle tissue in PAI corresponded well with the results of MRI and histology. Photoacoustic tomography utilizing a MZI for ultrasound detection allows for imaging of small tissue samples. Due to its high spatial resolution, good soft tissue contrast and comparatively low cost, PAT offers great potentials for imaging.
Insights
Photoacoustic imaging (PAI) effectively visualizes myocardial infarction in mouse hearts, offering high-resolution 3D images comparable to MRI and histology. This technique shows promise for small organ imaging.
Area of Science:
- Biomedical Imaging
- Medical Diagnostics
- Cardiovascular Research
Background:
- Myocardial infarction diagnosis relies on various imaging modalities.
- Ex vivo imaging of small animal organs presents unique challenges.
- Photoacoustic imaging (PAI) offers potential for high-resolution tissue visualization.
Purpose of the Study:
- To evaluate the applicability of ex vivo photoacoustic imaging (PAI) for small animal organs.
- To visualize and characterize myocardial infarction in murine hearts using photoacoustic tomography (PAT).
- To compare PAT findings with established imaging techniques and histology.
Main Methods:
- Induction of myocardial ischemia via left anterior descending artery ligation in wild-type mice.
- Ex vivo heart sample preparation and fixation.
- Photoacoustic tomography (PAT) using laser illumination and a Mach-Zehnder interferometer (MZI) for ultrasound detection.
- Fourier-domain reconstruction and inverse Radon transforms for 3D image generation.
Main Results:
- PAI successfully visualized infarcted areas in murine hearts with a spatial resolution of approximately 120 μm.
- Three-dimensional images of myocardial infarction were generated.
- PAT results showed strong correlation with magnetic resonance imaging (MRI), micro-computed tomography, and histological findings.
Conclusions:
- Ex vivo photoacoustic tomography (PAT) is a capable method for visualizing myocardial infarction in small animal organs.
- PAT provides high spatial resolution and good soft tissue contrast.
- PAT demonstrates significant potential for advanced biomedical imaging applications due to its effectiveness and cost-efficiency.
