Polarization-sensitive optical coherence tomography (PS-OCT) provides intrinsic contrast related to tissue microstructure. In the past, PS-OCT has been successfully used for imaging the anterior eye of humans in a variety of pathologic conditions. Here, we present PS-OCT imaging of the anterior eye in mice. Spectral domain PS-OCT centered at a wavelength of 840 nm was performed in anaesthetized laboratory mice. Three dimensional data sets were acquired at a 70 kHz A-line rate. PS-OCT images displaying phase retardation, birefringent axis orientation and degree of polarization uniformity (DOPU) were computed. Similar to human anterior segments, depolarization was observed in the corneal stroma and in structures containing melanin pigments such as the iris and the ciliary body. Birefringence was detected in the sclera close to the limbus. Aside from depolarizing foci observed within structures affected by cataract, the lens appeared mostly polarization preserving. Increased birefringence was observed in a scarred cornea. Given the similarity of the polarization characteristics in the murine eye and the human eye, PS-OCT lends itself as an ideal candidate for non-invasive imaging in preclinical studies in mouse models of anterior segment pathology.
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