Spatial profiles of the optical fluence distribution in live tissues can be used for noninvasive measurements of tissue optical properties. Axial profiles of the optical fluence distribution can be, in turn, measured from the spatial... more
Spatial profiles of the optical fluence distribution in live tissues can be used for noninvasive measurements of tissue optical properties. Axial profiles of the optical fluence distribution can be, in turn, measured from the spatial profiles of the laser induced optoacoustic pressure. Short (nansecond) laser pulses and ultrawideband ultrasonic transducers enable these measurements.
Detection of tumor metastases in the lymphatic system is essential for accurate staging of malignancies. Commercially available superparagmagnetic nanoparticles (SPIOs) accumulate in normal lymph tissue after injection at a tumor site,... more
Detection of tumor metastases in the lymphatic system is essential for accurate staging of malignancies. Commercially available superparagmagnetic nanoparticles (SPIOs) accumulate in normal lymph tissue after injection at a tumor site, whereas less or no accumulation takes place in metastatic nodes, thus enabling lymphatic staging using MRI. We verify for the first time the potential of SPIOs, such as Endorem(®) as a novel photoacoustic (PA) contrast agent in biological tissue. We injected five Wistar rats subcutaneously with variable amounts of Endorem(®) and scanned the resected lymph nodes using a tomographic PA setup. Findings were compared using histology, vibrating sample magnetometry (VSM) and 14 T MR-imaging. Our PA setup was able to detect the iron oxide accumulations in all the nodes containing the nanoparticles. The distribution inside the nodes corresponded with both MRI and histological findings. VSM revealed that iron quantities inside the nodes varied between 51 ± 4 a...
