biostudies-literatureUnknown29(Suppl 1)Hirasawa T<h4>Significance</h4>We developed a high-speed optical-resolution photoacoustic microscopy (OR-PAM) system using a high-repetition-rate supercontinuum (SC) light source and a two-axes Galvano scanner. The OR-PAM system enabled real-time imaging of optical absorbers inside biological tissues with excellent excitation wavelength tunability.<h4>Aim</h4>In the near-infrared (NIR) wavelength range, high-speed OR-PAM faces limitations due to the lack of wavelength-tunable light sources. Our study aimed to enable high-speed OR-PAM imaging of various optical absorbers, including NIR contrast agents, and validate the performance of high-speed OR-PAM in the detection of circulating tumor cells (CTCs).<h4>Approach</h4>A high-repetition nanosecond pulsed SC light source was used for OR-PAM. The excitation wavelength was adjusted by bandpass filtering of broadband light pulses produced by an SC light source. Phantom and <i>in vivo</i> experiments were performed to detect tumor cells stained with an NIR contrast agent within flowing blood samples.<h4>Results</h4>The newly developed high-speed OR-PAM successfully detected stained cells both in the phantom and <i>in vivo</i>. The phantom experiment confirmed the correlation between the tumor cell detection rate and tumor cell concentration in the blood sample.<h4>Conclusions</h4>The high-speed OR-PAM effectively detected stained tumor cells. Combining high-speed OR-PAM with molecular probes that stain tumor cells <i>in vivo</i> enables <i>in vivo</i> CTC detection.Journal of biomedical opticsS11527https://www.ebi.ac.uk/biostudies/studies/S-EPMC10924425biostudies-literaturePhotoacoustic microscopy for real-time monitoring of near-infrared optical absorbers inside biological tissue.PMC10924425Ishikawa TIto KTachi KHirasawa TIshihara MMiyashita MfalsePhotoacoustic microscopy for real-time monitoring of near-infrared optical absorbers inside biological tissue.<h4>Significance</h4>We developed a high-speed optical-resolution photoacoustic microscopy (OR-PAM) system using a high-repetition-rate supercontinuum (SC) light source and a two-axes Galvano scanner. The OR-PAM system enabled real-time imaging of optical absorbers inside biological tissues with excellent excitation wavelength tunability.<h4>Aim</h4>In the near-infrared (NIR) wavelength range, high-speed OR-PAM faces limitations due to the lack of wavelength-tunable light sources. Our study aimed to enable high-speed OR-PAM imaging of various optical absorbers, including NIR contrast agents, and validate the performance of high-speed OR-PAM in the detection of circulating tumor cells (CTCs).<h4>Approach</h4>A high-repetition nanosecond pulsed SC light source was used for OR-PAM. The excitation wavelength was adjusted by bandpass filtering of broadband light pulses produced by an SC light source. Phantom and <i>in vivo</i> experiments were performed to detect tumor cells stained with an NIR contrast agent within flowing blood samples.<h4>Results</h4>The newly developed high-speed OR-PAM successfully detected stained cells both in the phantom and <i>in vivo</i>. The phantom experiment confirmed the correlation between the tumor cell detection rate and tumor cell concentration in the blood sample.<h4>Conclusions</h4>The high-speed OR-PAM effectively detected stained tumor cells. Combining high-speed OR-PAM with molecular probes that stain tumor cells <i>in vivo</i> enables <i>in vivo</i> CTC detection.2024-01-01T00:00:00Z2024 Jan2025-04-04T12:58:40.454Z2025-04-04T12:58:40.454ZS-EPMC109244253846488310.1117/1.JBO.29.S1.S11527