Advancing biomedical imaging

Abstract

Imaging reveals complex structures and dynamic interactive processes, located deep inside the body, that are otherwise difficult to decipher. Numerous imaging modalities harness every last inch of the energy spectrum. Clinical modalities include magnetic resonance imaging (MRI), X-ray computed tomography (CT), ultrasound, and light-based methods [endoscopy and optical coherence tomography (OCT)]. Research modalities include various light microscopy techniques (confocal, multiphoton, total internal reflection, superresolution fluorescence microscopy), electron microscopy, mass spectrometry imaging, fluorescence tomography, bioluminescence, variations of OCT, and optoacoustic imaging, among a few others. Although clinical imaging and research microscopy are often isolated from one another, we argue that their combination and integration is not only informative but also essential to discovering new biology and interpreting clinical datasets in which signals invariably originate from hundreds to thousands of cells per voxel.

Multimodal Nonlinear Optical Imaging of Live Cells Using Plasmon-Coupled DNA-Mediated Gold Nanoprism Assembly

“…Multiphoton microscopy via coupling of nonlinear optics (NLO) and scanning microscopy has opened up the possibility of new discovery for breakthrough in biology 1–10 . NLO imaging using second harmonic generation (SHG) and two-photon luminescence (TPL) are the emerging techniques to watch the biological world due its ability to penetrate deep into living tissue 11–20 .…”

“…In last one decade, due to the huge advances in the innovative developments of laser systems, detector devices and optical filter design, we are now able to use the combination of several NLO modalities for advancing biological imaging into a single microscope platform, which is known as multimodal NLO imaging 21–30 . For in vivo imaging using noninvasive technology, near infrared (NIR) light between 650–950 nm (biological I window) and 1000–1350 nm (biological II window) needs to be used for providing maximum radiation penetration through tissue 1–5,11–13,31–33 . To date, most of the cell imaging is reported using biological I window (650–950 nm) NIR light, although it is well documented that due to the substantial background noise from tissue autofluorescence and the tissue penetration depth is limited to 1–2 cm, biological I window is not optimal 1–5,11–13 .…”

“…For in vivo imaging using noninvasive technology, near infrared (NIR) light between 650–950 nm (biological I window) and 1000–1350 nm (biological II window) needs to be used for providing maximum radiation penetration through tissue 1–5,11–13,31–33 . To date, most of the cell imaging is reported using biological I window (650–950 nm) NIR light, although it is well documented that due to the substantial background noise from tissue autofluorescence and the tissue penetration depth is limited to 1–2 cm, biological I window is not optimal 1–5,11–13 . However, due to the lack of available biocompatible probes in biological II window, clinical research has prevented the use of this highly sensitive spectral range for cancer imaging where one could improve signal-to-noise ratios by over 100-fold 1–5,11–13 .…”

“…To date, most of the cell imaging is reported using biological I window (650–950 nm) NIR light, although it is well documented that due to the substantial background noise from tissue autofluorescence and the tissue penetration depth is limited to 1–2 cm, biological I window is not optimal 1–5,11–13 . However, due to the lack of available biocompatible probes in biological II window, clinical research has prevented the use of this highly sensitive spectral range for cancer imaging where one could improve signal-to-noise ratios by over 100-fold 1–5,11–13 . Driven by the need, this article reports the design of a DNA-mediated nanoprism assembly which has the capability for multimodal nonlinear optical SHG and TPL imaging using biological II window excitation light.…”

Quantitative vascular neuroimaging of the rat brain using superparamagnetic nanoparticles: New insights on vascular organization and brain function

“…Importantly, the QUTE-CE MRI method is readily translatable to clinical studies since ferumoxytol is FDA-approved for use in humans and is already used off-label for human MRI (Neuwelt et al, 2009; Weinstein et al, 2010; Weissleder and Nahrendorf, 2015). However, further work may be necessary to facilitate this translation due to the challenges of UTE on clinical scanners.…”