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Schmidt, C. C.

Publications and source records attributed to Schmidt, C. C..

2 recordsLinked to original sources

Compact and contactless reflectance confocal microscope for neurosurgery

Visual guidance at the cellular level during neurosurgical procedures is essential for complete tumour resection. We present a compact reflectance confocal microscope with a 20 mm working distance that provided <1.2 {micro}m spatial resolution over a 600 {micro}m x 600 {micro}m field of view in the near-infrared region. A physical footprint of 200 mm x 550 mm was achieved using only standard off-the-shelf components. Theoretical performance of the optical design was first evaluated via commercial Zemax software. Then three specimens from rodents: fixed brain, frozen calvaria and live hippocampal slices, were used to experimentally assess system capability and robustness. Results show great potential for the proposed system to be translated into use as a next generation label-free and contactless neurosurgical microscope.

neuroscience

Two-photon fluorescence imaging of live neurons using a multimode optical fiber

Multimode optical fibers (MMFs), combined with wavefront control methods, have achieved minimally-invasive in vivo imaging of neurons in deep-brain regions with diffraction-limited spatial resolution. Here, we report a method for volumetric two-photon fluorescence imaging with a MMF-based system requiring a single transmission matrix measurement. Central to this method is the use of a laser source able to generate both continuous wave light and femtosecond pulses. The chromatic spreading of pulses generated an axially elongated excitation focus, which we used to demonstrate volumetric imaging of neurons and their dendrites in live rat brain slices through a 60 m-core MMF.

neuroscience