Efficient second-harmonic imaging of collagen in histological slides using Bessel beam excitation.

ABSTRACT: Second-harmonic generation (SHG) is the most specific label-free indicator of collagen accumulation in widespread pathologies such as fibrosis, and SHG-based measurements hold important potential for biomedical analyses. However, efficient collagen SHG scoring in histological slides is hampered by the limited depth-of-field of usual nonlinear microscopes relying on focused Gaussian beam excitation. In this work we analyze theoretically and experimentally the use of Bessel beam excitation to address this issue. Focused Bessel beams can provide an axially extended excitation volume for nonlinear microscopy while preserving lateral resolution. We show that shaping the focal volume has consequences on signal level and scattering directionality in the case of coherent signals (such as SHG) whic

SUBMITTER: Vuillemin N 

PROVIDER: S-EPMC4951755 | biostudies-literature | 2016 Jul

REPOSITORIES: biostudies-literature