Now showing 1 - 5 of 52
- ItemDual wavelengths inverse spatially offset Raman spectroscopy for bone characterization(Society of Photo-Optical Instrumentation Engineers (SPIE), 2023-03-06) Ma, Hui; Gautam, Rekha; Konugolu Venkata Sekar, Sanathana; O'Flynn, Carrie; Henn, Patrick; Andersson-Engels, Stefan; Boudoux, Caroline; Tunnell, James W.Osteoporosis is a disease that weakens bones increasing the possibility of bone fracture. The gold standard to diagnose osteoporosis is measuring bone mineral density (BMD). Since BMD only partly determines the strength of the bone, more information on chemical composition and microstructure is needed. Here, we implemented a novel dual-wavelength inverse Spatially Offset Raman Spectroscopy (SORS) to characterize tissue chemical composition covering both the fingerprint and high-wavenumber regions. This system provides a greater probing depth keeping the spectrometer setting constant. The results from hydroxyapatite (HA) and water phantom demonstrate the potential of the Raman system to assess bone mineral and matrix quality in-vivo.
- ItemTime resolved SPAD micro-camera probe for wide-field FLIm in microendoscopy(Society of Photo‑Optical Instrumentation Engineers (SPIE), 2023-03-06) Angelone, Dario; Konugolu Venkata Sekar, Sanathana; Messina, Walter; Matheson, Andrew B.; Erdogan, Ahmet T.; Henderson, Robert K.; Burke, Ray; Andersson-Engels, Stefan; James W. Tunnell; Horizon 2020; Science Foundation Ireland; EPSRC Interdisciplinary Research CollaborationWe propose a handheld single photon avalanche diode (SPAD) micro-camera probe for wide-field in-vivo fluorescence lifetime imaging (FLIm) applications. The presented probe includes a novel 3D stacked 1.4 mm × 1.4 mm SPAD array, an integrated excitation light source, and imaging optics. The spatial and temporal performance of the integrated system was characterised using a USAF test target and range of fluorescence lifetime beads.
- ItemColorectal cancer detection based on the extraction of scattering properties and biochemical concentrations from fluorescence spectroscopy measurements(Optica Publishing Group, 2022-04) Nogueira, Marcelo S.; Matthews, Robert; Killeen, Shane; Oâ Riordain, Micheal; Andersson-Engels, Stefan; Science Foundation IrelandWe report the first study estimating fluorophore and chromophore concentrations with scattering properties for colorectal cancer detection, as well as one of the first studies performing such estimation based on fluorescence spectra alone.
- ItemInvestigation of lung volume measurements in neonates using gas in scattering media absorption spectroscopy(Optica Publishing Group, 2022-04) Pacheco, Andrea; Jayet, Bapiste; Grygoryev, Konstantin; Messina, Walter; Dehghani, Hamid; Krite Svanberh, Emilie; Dempsey, Eugene M.; Andersson-Engels, Stefan; Science Foundation IrelandWe perform phantom and numerical studies of the changes in molecular oxygen and water vapor spectroscopic signals, showing the potential of measuring pulmonary volume changes with GASMAS technique in neonates.
- ItemMiniaturized, multi-spectral optics for tissue differentiation(Optica Publishing Group, 2022-04) Grygoryev, Konstantin; Lu, Huihui; Sorensen, Simon; Li, Celina L.; Georgel, Rachel; Oâ Hare, Daniel; Burke, Ray; Andersson-Engels, StefanIdentification of tumour margins during resection of the brain is critical for improving the post-operative outcomes. Present research aims to develop a miniaturized, optical system for simultaneous measurement of DRS and auto-fluorescence for brain tumour detection.