title: Measurement of the ratio of forward-propagating to back-propagating second harmonic signal using a single objective.
abstract: In this paper, we present a method to determine, for the first time, the ratio of forward-propagating second harmonic (SHG) signal to back-propagating SHG signal (F/B) in vivo on the surface of intact tissue samples without any biopsy or tissue sectioning, using only epidetection (i.e., via a single objective lens). This method has the additional benefit of using the confocal detection apparatus already contained within common commercially available two-photon laser-scanning microscopes, and hence can allow the measurement of the SHG F/B ratio in vivo with minimal purchase of new equipment.
authors.affiliation: Institute of Optics, University of Rochester, Rochester, New York 14627, USA.
authors.forename: Xiaoxing
authors.initials: X
authors.lastname: Han
authors.forename: Edward
authors.initials: E
authors.lastname: Brown
mesh_terms: D004867:Equipment Design; D019544:Equipment Failure Analysis; D007089:Image Enhancement / Q000295:instrumentation* / Q000379:methods; D007909:Lenses; D018613:Microscopy, Confocal / Q000295:instrumentation* / Q000379:methods; D036641:Microscopy, Fluorescence, Multiphoton / Q000295:instrumentation* / Q000379:methods; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity