Clinical applications of spectral molecular imaging: potential and challenges

Abstract

Spectral molecular imaging is a new X-ray-based imaging technology providing highly specific 3D imaging at high spatial resolution that has the potential to measure disease activity and response to treatment noninvasively. The ability to identify and quantify components of tissue and biomarkers of disease activity derive from the properties of the photon-processing detector. Multiple narrow sections of the energy spectrum are sampled simultaneously, providing a range of energy dependent Hounsfield units. As each material has a specific measurable X-ray spectrum, spectroscopic imaging allows for multiple materials to be quantified and differentiated from each other simultaneously. The technology, currently in its infancy, is set to grow rapidly, much as magnetic resonance did. The critical clinical applications have not yet been established, but it is likely to play a major role in identifying and directing treatment for unstable atherosclerotic plaque, assessing activity and response to treatment of a range of inflammatory diseases, and monitoring biomarkers of cancer and its treatment. If combined with Positron-emission tomography (PET), spectral molecular imaging could have a far greater effective role in cancer diagnosis and treatment monitoring than PET-CT does at present. It is currently used for small animal and specimen imaging. There are many challenges to be overcome before spectral imaging can be introduced into clinical medicine - these include technological improvements to detector design, bonding to the semiconductor layer, image reconstruction and display software, identifying which biomarkers are of most relevance to the disease in question, and accelerating drug discovery enabled by the new capabilities provided by spectral imaging.

Gold Nanoparticles as Contrast Agents in x-ray Imaging and Computed Tomography

“…Continued incremental improvements to CT have included: spiral CT in the late 1980s, which improved spatial resolution; multislice imaging in the early 2000s, which decreased scan time; helical cone-beam CT technologies, which are currently emerging for rapid scanning at high spatial resolution; and the continuous development of new reconstruction algorithms for handling the scanning patterns associated with helical or cone-beam Gold nanoparticles as contrast agents in x-ray imaging and computed tomography future science group Review Cole, Ross, Tilley, Vargo-Gogola & Roeder CT [4,5]. Current developments include the clinical introduction of dual-energy CT [6] and research into spectral (color) CT [7,8].…”

Exosomes as divine messengers: are they the Hermes of modern molecular oncology?

“…[70][71][72] In addition, these signatures might contribute by confirming or discarding the results of biomarkers that are nowadays considered standard of care, such as the prostate-specific antigen (PSA), 73 carbohydrate antigen CA-90 or CA-125. 74 Exosomes are intercellular carriers of many molecules and, thus, they may be considered as novel sources of unknown potential biomarkers.…”

Dual-energy computed tomography for detection of coronary artery disease

“…A limitation of dual-source CT is the use of two moderately broad energy spectra, restricting tissue and material discrimination. [11] However, this problem can be partly corrected for by filtering the high-energy beam. [12] An advantage of this system is the freely adjustable tube voltage.…”