Schematic of the wide-field multiphoton imaging system. Source: University of St. Andrews
The ability to optically image through tissue could allow for a more detailed understanding and diagnosis of the early stages of various diseases, including cancer. A wide-field multiphoton imaging technology advanced in the U.K. accomplishes such imaging functionality by focusing short pulses of patterned light in time through tissue.
The use of temporal focusing allows light patterns to retain their form despite scattering from the tissue. To effect imaging, a fraction of the return light, or fluorescence, is collected from the sample onto a single-point detector. A true image is formed by summing the patterns projected on the sample weighted by the intensities recorded for the return light.
The combination of temporal focusing and single-pixel detection yields wide-field two-photon images through various turbid media including a scattering phantom and tissue reaching a depth of up to seven scattering mean free path lengths. The method compares favorably with standard point-scanning two-photon imaging, with up to a fivefold improvement in signal-to-background ratio while showing significantly lower photobleaching.
Scientists from the University of St. Andrews, the University of Southampton and the University of Edinburgh contributed to this research, which is published in Science Advances.
