Instrumentation and Technology

The NeuroExplorer is an ultra-high-performance brain PET imager for highly resolved in vivo imaging of neurochemistry. Brain-dedicated PET systems offer important advantages over currently available PET systems, but the state-of-the-art for brain PET imaging systems has not progressed beyond the 20-year-old HRRT. The new next-generation NeuroEXPLORER (NX) PET system has a factor of 10 greater sensitivity and can dramatically expand the scope of human brain PET protocols and applications. We are part of the team working on this project to contribute kinetic modeling that incorporates accurate measurements of blood activity to avoid arterial blood sampling and demonstrate performance on novel human imaging paradigms.

Investigator: Richard Carson

Studies demonstrating the performance of the NX include tracers targeting SV2A (18F-SynVesT-1), dopamine D2/D3 receptors (11C-PHNO), M1 muscarinic receptors (11C-LSN3172176), and dopamine transporters (DAT, 18F-FE-PE2I). The radiotracer images show exceptional resolution in the cortex and subcortical structures. For SV2A (A), there is clear identification of high flow regions in early images, while the late images show that the synaptic density pattern differs from the flow pattern. D2/3 binding potential images (B) show well-defined delineation of the substantia nigra, high binding along the nigrostriatal tract, and focal medial bilateral binding in a thalamic nucleus. Dramatic distribution changes, particularly in the cerebellum, are visualized clearly in the M1 images (C & D). The substantia nigra is clearly visualized in the DAT images (E & F).

We are leading the team applying the NX system in human studies using a wide range of targeted radiopharmaceuticals with novel human imaging paradigms. The incredible images provided by the NX were awarded the Image-of-the-Year at the 2024 SNMMI annual meeting (SNMMI Image of the Year: Ultra-High-Resolution PET Provides Never Before Seen Images of the Brain).

The SAVANT brain PET scanner is a cutting-edge device designed to revolutionize brain imaging with its ultra-high resolution, crucial for diagnosing and treating neurodegenerative diseases like Alzheimer's and Parkinson's. It provides detailed visualization of small brain regions, significantly improving understanding and treatment of these conditions. Utilizing advanced technology, the SAVANT scanner processes data rapidly and accurately, producing images with resolutions between 1.25 mm and 1.75 mm. Its sophisticated detectors and algorithms allow for highly detailed brain images, aiding in the study of tau protein buildup and dopamine-producing neurons.

Investigator: Georges El Fakhri

We are developing multi-coil arrays for use in human and small animal MR scanners. The improved field shaping of the MCAs allows for greater magnetic field homogeneity and higher quality images. Field uniformity is especially important in magnetic resonance spectroscopy (MRS), which relies on the detection of very small chemical shifts”. Field homogeneity is also important in the brain, where large differences in magnetic susceptibility in the nasal passages can result in field distortions.

References:

Human multi-coil arrays (MCA)

• Juchem et al, MRM 63, 171 (2010)
• Juchem et al, JMR 212, 280 (2011)
• Juchem et al, NeuroImage 105, 462 (2015)
• Rudrapatna et al, MRM 76, 83 (2016)
• C. Juchem et al. Magn. Reson. Med. 84, 2953-2963 (2020)
• S. Theilenberg et al. Magn. Reson. Med. 90, 1228 (2023)

Rodent multi-coil arrays (MCA)

• Juchem et al, JMR 204, 281 (2010)
• Juchem et al, MRM 66, 893 (2011)
• Juchem et al, JMR 236, 95 (2013)
• Juchem et al, NBM 27, 897 (2014)
• Juchem et al, NBM 28, 1526 (2015)

Investigator: Robin de Graaf

Elliptical localization with pulsed-second-order fields (ECLIPSE) is a novel method developed at Yale for robust (> 100-fold) lipid suppression with high brain coverage and low RF power requirements. Lipid suppression is especially important in magnetic resonance spectroscopy (MRS), which can detect subtle alterations in the neurochemical profile by identifying individual metabolites. For instance, elevated levels of lactate have been reported in tumors, stroke, and hypoxia.

References:

• R. A. de Graaf et al, NMR Biomed. 31, e3949 (2018)
• Kumaragamage et al, NMR Biomed (2021)
• Kumaragamage et al, J Magn Reson (2022)
• Kumaragamage et al, NeuroImage (2024)

Investigator: Robin de Graaf

While mammography is the current standard of care for breast cancer screening, its sensitivity is not very high. MRI can provide much more sensitive images but is prohibitively expensive for routine screening. We are developing technology that will allow for portable, breast-specific MRI devices using smaller, cheaper magnets at a tenth of the cost of standard MRI.

This project is sponsored by ARPA-H

Investigator: Todd Constable

See the DMI lab page for more details and resources

DMI is an innovative MR-based method for non-invasive 3D metabolic mapping using deuterium (2H) isotopes. It images 2H-enriched substrates like [6,6-2H2]-glucose and 2H3-acetate to study energy metabolism pathways. The process involves: administering the 2H-enriched substrate (via intravenous infusion or orally), the body's metabolism of the substrate, using MR imaging with 2H acquisition methods (either dynamically or at steady-state), and quantifying data through spectral fitting, displayed as color-coded maps.

Investigators: Robin de Graaf, Henk De Feyter

In collaboration with engineers at the University of Illinois Urbana-Champaign, we developed a Dynamic Extremity SPECT (DE-SPECT) system that utilizes 3D HEXIETC CZT detector technology and a synthetic compound-eye camera design for dynamic and multi-tracer SPECT imaging of peripheral arterial disease (PAD) in lower extremities. The DE-SPECT system provides a unique, non-invasive approach for comprehensively assessing molecular and physiological changes in the lower extremities, enabling the evaluation of response to therapeutic interventions - a critical step for optimizing and monitoring PAD therapy.

Investigator: Albert Sinusas, MD

The interaction of light with nanophotonic materials reveals unique properties like photonic bandgaps, negative refraction, and diffraction-free light propagation, enabling applications in health care, life sciences, energy, and environmental monitoring. Our institute develops novel nano/quantum optical materials, including nanoparticles, photonic crystals, and metamaterials. These materials push technological boundaries, particularly in healthcare, where they enhance imaging techniques and enable precise drug delivery. Our interdisciplinary collaboration among physicists, engineers, biologists, and materials scientists fosters innovation and accelerates the practical application of nanophotonics.

Investigator: Yue Zhuo