Nuclear Scans and Cardiac Molecular Imaging – A Snapshot
Published on 23 Sep, 2016
Recently developed radio-pharmaceuticals agents could significantly improve the diagnosis, treatment, and prediction of heart disease.
A relatively new diagnostic method, cardiac nuclear imaging involves the use of radioactive substances in the diagnosis and treatment of disease.
It’s specifically used to map internal physiological functionality, using novel radio-pharmaceuticals to assess metabolism, dysfunction, post-transplant cellular response, atherosclerotic pathophysiological progress, as well as tissue viability.
Nuclear scans are routinely used to visualize a patient’s cardiac physiology, and cardiac molecular imaging techniques include cell molecular biology, radiotracers as well as imaging principles to visualize cardiac functioning.
Molecular imaging provides non-invasive, cost-effective, and in-vivo quantitative modality to study cardiac physiology, minimizing procedural hassles and making things as pain-free as possible for patients.
Current molecular imaging techniques mainly include:
- Single Photon Emission Tomography (SPECT Computed)
- Positron Emission Tomography (PET)
- Computed Tomography (CT)
- Magnetic Resonance Imaging (MRI)
- High Frequency Ultrasound Techniques based on Optical Fluorescence and Bioluminescence
A hybrid combination of these techniques is also being explored to improve efficiency and accuracy in the detection of disease-specific changes in tissue.
Molecular imaging has a variety of diagnostic applications in cardiac medicine, some of which include:
- Imaging atherosclerotic plaques in ischemic cardiac diseases.
- Identifying small abdominal aortic aneurysms that could be predisposed to sudden ruptures.
- Ischemic cardiac assessment using glucose or fatty acid based analogs.
- Post-infarct assessment, using radiotracers targeted toward metalloproteinase and renin angiotensin systems.
- Sympathetic innervation studies, performed on cardiomyopathy patients who are at risk of developing arrhythmia.
- Stem cell transplant assessment, using reporter-based gene imaging in clinical trials.
Molecular imaging has evolved from many aspects of nuclear imaging.
Scintiography, SPECT, and PET scans using a radiotracer element and gamma camera to capture images have been employed in clinical diagnostics over the past three decades.
SPECT and PET are advantageous in their high sensitivity, widespread availability, and low cost as compared to prevalent techniques. PET also provides better quantitative information and allows the dynamic analysis of cardiac physiology.
This technology does have its limitations however, with spatial resolution, the necessity of an onsite cyclotron for PET scanning, attenuation artifacts, and the partial volume effect to name a few.
Current research has focused on the development of hybrid technologies such as PET/CT and PET/MRI to increase image quantification.
Check out our report on Cardiac Nuclear Imaging and Radiotracers for more on developments in the field of radiotracers used for cardiac imaging.