Deeper Photoacoustic Imaging for Clinical Translation

Deeper Photoacoustic Imaging for Clinical Translation

Photoacoustic (PA) imaging opens a new path to assess medical conditions where in vivo functional measurements are critical. The goal of this project is to extend PA imaging depth by – 1) studying light delivery systems, the interaction of light with human placental tissue, and improve the depth resolution of PA imaging. Next, we aim to 2) characterize the PA imaging capabilities of novel biodegradable and biocompatible NIR-II contrast agents that facilitate in vivo PA imaging at clinically relevant depths. Successful detection of placental hypoxia will allow us to noninvasively monitor the effect of placental ischemia during human pregnancy.

Non-toxic NIR-II contrast agents

Contrast enhanced photoacoustic (PA) imaging has the potential for deep tissue imaging, but clinically approved exogenous agents, such as indocyanine green (ICG), have poor photostability, low photothermal efficiency and poor blood retention that limit their use in vivo. Additionally, commonly used PA contrast agents have optical extinction peaks in the first near infrared (NIR-I) window, where light attenuation by tissue is high. Plasmonic nanoparticles (NPs) have high tunable localized surface plasmon resonance (LSPR)induced optical extinction, allowing imaging at NIR-II wavelengths where light penetration is maximized in biological tissues. However, conventional plasmonic NPs, such as gold nanorods (AuNRs) bioaccumulate at sizes needed for NIR-II LSPR. Semiconductor nanocrystals (NCs), such as copper sulfides (CuxS), exhibit NIR-II optical extinction without size modulation. However, compared to AuNRs, typical CuxS have reduced peak LSPR due to lower densities of free charge carriers. Hence, our group is interested in characterizing novel biocompatible and biodegradable NIR-II PA contrast agent capable of translating PA systems for transabdominal imaging.  

References

Vincely, V.D., Huda, K., Zhong, X., Dennis, A. and Bayer C.L., “A novel biocompatible and biodegradable NIR-2 agent for in-vivo photoacoustic imaging to improve overall image contrast” International Ultrasound Symposium. (07 September 2023)

Manuel, L. D. B., Vincely, V. D., Bayer, C.L., McPeak, K. M. “Monodisperse Sub-100 nm Au Nanoshells for Low-Fluence Deep-Tissue Photoacoustic Imaging”. Nano Letters (2023).

[DOI]

V.D. Vincely and C. L. Bayer. “Functional photoacoustic imaging for placental monitoring: A mini review”. IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control. (2023).

[DOI]

Vincely, V.D., Katakam, S.P., Huda, K., Zhong, X., Kays, J.C., Dennis, A. and Bayer C.L., “Biodegradable and biocompatible semiconductor nanocrystals as NIR-II photoacoustic imaging contrast agents” Proc. SPIE 12379-137, Photons Plus Ultrasound: Imaging and Sensing 2023 (30 January 2023) [POSTER]

Vincely, V.D. and Bayer C.L., “Simulations-informed optimization of photoacoustic imaging depth and validation with phantoms.” Proc. SPIE 12379-164, Photons Plus Ultrasound: Imaging and Sensing 2023 (30 January 2023) [POSTER]

Katakam, S. P., Vincely, V. D., Bayer, C. L., “Improved Photoacoustic Signal Stability in Melanin Phantom with NIR-II Wavelengths,” 2022 BMES Conference: Biomedical Imaging and Instrumentation, (12-15 October 2022) [POSTER]

Vincely, V.D., and Bayer, C.L., “Improved estimation of hemoglobin oxygen saturation derived from spectral photoacoustic images within NIR-II,” Gordon 2022 Research Conference: In Vivo Ultrasound Imaging, (14-19 August 2022) [POSTER];

Vincely, V.D., Katakam, S., Kays, J., Dennis., Allison, Bayer, C.L., “Deeper photoacoustic imaging in tissue using an NIR-II contrast agent,” Optica Biophotonics Congress 2022, (27 April 2022);

Huda, K, Swan, KF, Gambala, CT, Bayer CL,. Towards Transabdominal Functional Photoacoustic Imaging of the Placenta: Improvement in Imaging Depth Through Optimization of Light Delivery. Ann Biomed Eng 49, 1861–1873 (2021).

[DOI]

Huda, K., Bayer, CL, “Monte Carlo simulation for improving spectral photoacoustic imaging-based oxygen saturation estimation of human placental tissue,” Proc. SPIE 11240, Photons Plus Ultrasound: Imaging and Sensing 2020, 112400D (17 February 2020);

[DOI]

Huda, K, Kolkin, AD, Bayer, CL, “Improving Spectral Photoacoustic Imaging-Based Oxygen Saturation Estimates of Ex Vivo Human Placenta Through Simulation”, BMES 2019 Annual Meeting, October 19, 2019, Philadelphia, PA.

[DOI]