Positron emission tomography (PET) is a nuclear imaging technology (also referred to as molecular imaging) that enables visualization of metabolic processes in the body. The basics of PET imaging is that the technique detects pairs of gamma rays emitted indirectly by a positron-emitting radionuclide (also called radiopharmaceuticals, radionuclides or radiotracer). The tracer is injected into a vein on a biologically active molecule, usually a sugar that is used for cellular energy. PET systems have sensitive detector panels to capture gamma ray emissions from inside the body and use software to plot to triangulate the source of the emissions, creating 3-D computed tomography images of the tracer concentrations within the body.
Application of dual-modality optical and PET/CT activity-based probe in experimental carotid inflammation model. Coronal noninvasive PET/CT scans of (A) healthy and (B) diseased mice with and without ligated carotid arteries respectively. Inset images show optical ex vivo florescence imagining of (A) healthy and (B) diseased carotid arteries. PET/CT and optical images courtesy of Xiaowei Ma, Toshinobu Saito and Nimali Withana.
Digital technology is opening remarkable opportunities for clinical...
Panel A shows a flank A549 lung tumor in a nude mouse with combined 18F-FDG PET uptake (signal intensity in color) and T2-weighted anatomical MRI (grayscale). Panel B shows a similar tumor image with a relative permeability map for the tumor (color code) overlaid on a corresponding anatomical MRI reference. Regions identified as necrotic were not included in the DCE MRI analysis. Image courtesy of the University of Arizona Department of Medical Imaging.
Precision can have an enormous impact on patients.
PET is getting ready to venture outside oncology, cardiology and mainstream neurology.
Analog is approximate. Digital is specific. Therein lies the fundamental difference between digital PET and its...
Example of the iDISCO technique to image brain samples containing Alzheimer’s disease, which could have major impact on treatment. For more inages and videos view the article online at www.cell.com/cell-reports/fulltext/S2211-1247(16)30814-2
A PET-CT head and neck cancer scan showing various image reconstructions. The top left image is the separate CT scan showing the anatomy. The top right scan shows the fused PET and CT scans with false color added to help interpret the image. The bottom left scan is an initial FDG PET image showing tracer hot spots in the neck and a lymph node in the right jaw due to cancer. The right bottom image is a delayed enhancement scan showing tracer uptake over time, with normal hot spots in the bladder, kidneys, testicles and brain, which normally have higher metabolic activity. The low-grade gray shading of the anatomy is due to the normal cellular metabolism uptake of the FDG throughout the body.