Brain heating induced by near-infrared lasers during multiphoton microscopy

Brain heating induced by near-infrared lasers during multiphoton microscopy.

Two-photon imaging and optogenetic stimulation rely on high illumination powers, particularly for state-of-the-art applications that target deeper structures, achieve faster measurements, or probe larger brain areas. However, little information is available on heating and resulting damage induced by high-power illumination in the brain. In the current study we used thermocouple probes and quant...

Multiphoton microscopy with near infrared contrast agents.

While multiphoton microscopy (MPM) has been performed with a wide range of excitation wavelengths, fluorescence emission has been limited to the visible spectrum. We introduce a paradigm for MPM of near-infrared (NIR) fluorescent molecular probes via nonlinear excitation at 1550 nm. This all-NIR system expands the range of available MPM fluorophores, virtually eliminates background autofluoresc...

brain near-infrared spectroscopy (nirs)

near-infrared spectroscopy (nirs) is a spectroscopic method that uses the near-infrared region of the electromagnetic spectrum. typical applications include medical and physiological diagnostics. nirs can be used for non-invasive assessment of brain function through the intact skull in human subjects by detecting changes in blood hemoglobin concentrations associated with neural activity, e.g., ...

Brain Imaging with Multiphoton Microscopy

Picosecond multiphoton scanning near-field optical microscopy.

We have implemented simultaneous picosecond pulsed two- and three-photon excitation of near-UV and visible absorbing fluorophores in a scanning near-field optical microscope (SNOM). The 1064-nm emission from a pulsed Nd:YVO4 laser was used to excite the visible mitochondrial specific dye MitoTracker Orange CM-H2TMRos or a Cy3-labeled antibody by two-photon excitation, and the UV absorbing DNA d...