Terahertz technology in intraoperative neurodiagnostics: A review

Abstract

Terahertz (THz) technology offers novel opportunities in biology and medicine, thanks to the unique features of THzwave interactions with tissues and cells. Among them, we particularly notice strong sensitivity of THz waves to the tissue water, as a medium for biochemical reactions and a main endogenous marker for THz spectroscopy and imaging. Tissues of the brain have an exceptionally high content of water. This factor, along with the features of the structural organization and biochemistry of neuronal and glial tissues, makes the brain an exciting subject to study in the THz range. In this paper, progress and prospects of THz technology in neurodiagnostics is overviewed, including diagnosis of neurodegenerative disease, myelin deficit, tumors of the central nervous system (with an emphasis on brain gliomas), and traumatic brain injuries. Fundamental and applied challenges in study of the THz-wave -brain tissue interactions and development of the THz biomedical tools and systems for neurodiagnostics are discussed.

Hemispherical Rutile Solid Immersion Lens for Terahertz Microscopy with Superior 0.06–0.11λ Resolution

“…The achieved record spatial resolution of the rutile-based THz SI microscope can find applications in different branches of THz science and technology. Among them, we particularly note medical diagnosis and biology, [31,56] non-destructive testing of materials, [57] and electronic circuits, [58] quality control in pharmaceutical [59] and food [60] industries.…”

“…[29]. We then applied our THz SI microscope to visualize margins and heterogeneity of the glioma models from rats ex vivo, [29][30][31] as well as to study heterogeneous decellularized tissues during their interactions with a humid atmosphere. [32] Up till now, further improvement of the SI microscopy resolution was hampered by the limited RIs of the naturally-occurring optically-transparent materials, which in the THz spectral range are typically lower than that of silicon n ⩽ 3.0-3.5.…”

“…[29]. We then applied our THz SI microscope to visualize margins and heterogeneity of the glioma models from rats ex vivo, [ 29–31 ] as well as to study heterogeneous decellularized tissues during their interactions with a humid atmosphere. [ 32 ]…”

Terahertz Radiation from High Electron Mobility Avalanche Transit Time Sources Prospective for Biomedical Spectroscopy

“…Technological advances in material sciences and microfabrication and device technologies in the last decade have facilitated the development of powerful sources, uncooled detectors and advanced imaging techniques, along with an extended scope for flexible electronics; biomedical, highfrequency sensing (particularly promising); and communication devices [42][43][44]. A few of the remarkable advancements in recent times leading the prospective application of THz in biomedical spectroscopy include [45,46]: THz wound and diabetic injury screening [47]; spectroscopy and imaging for cancer diagnosis [48][49][50]; a THz time-domain spectral (THz-TDS) system for biological macromolecule detection [51]; biomolecular and pathogen detection [52] and evaluation of transdermal drug delivery [53]; identification of tumor mutation in the central nervous system [54,55]; and intraoperative neurodiagnostics [56]. Further advancement in THz biophotonics, materials and instrumentation [57][58][59]; tissue imaging techniques [60][61][62]; and applied computing algorithms [63] may also open up newer frontiers in THz biomedical applications.…”

Sensitivity of Neuroblastoma and Induced Neural Progenitor Cells to High-Intensity THz Radiation

“…The recent advances in THz generation and detection techniques have led to widespread applications covering medical imaging, diagnostics, and therapy (see reviews [ 1 , 2 , 3 , 4 ]). These applications include the diagnosis of malignant and benign neoplasms [ 5 ], intraoperative neurodiagnostics [ 6 ], determination of the hydration level [ 7 ] and viability of tissue, as well as regulation of the expression of genes associated with systemic inflammatory diseases/cancer [ 8 ], and the application of Escherichia coli bacteria as biosensors for THz radiation [ 9 ]. Despite the low energy and non-ionizing nature of THz photons, one should be aware of the fundamental biological effects of THz radiation when developing THz-based diagnostic and therapeutic technologies.…”