Abstract
Purpose: :
To demonstrate the ability of full-range complex (FRC) spectral-domain (SD) polarization-sensitive optical coherence tomography (PS-OCT) to record three-dimensional (3D) reflectivity and birefringence images of human anterior chambers in vivo.
Methods: :
The method was based on a previously reported SD PS-OCT system. FRC SD PS-OCT was implemented without adding supplementary phase shifting devices to the instrument by using a modulation frequency generated by the galvo scanner that scans the probe beam in transversal direction. Thus, the accessible image range of the system was doubled to a total axial extension of 6.8 mm. Hence, cross-sectional imaging of entire human anterior chambers was enabled. A super luminescent diode centered at 840 nm was used as a light source. The power onto the cornea was 2.5 mW. The acquisition time for one 3D PS-OCT data set providing information on sample reflectivity, phase retardation, and optic axis orientation was 3 seconds.
Results: :
The spectral domain PS-OCT instrument was used to image anterior chambers in 10 healthy human eyes in vivo. In the PS-OCT images derived from the recorded data, different polarizing properties of different tissues (e.g., birefringent cornea, polarization-preserving stroma of the iris, depolarizing pigment epithelium of the iris) were observed. In addition to cross-sectional B-scan images, maps of polarization states at different surfaces were derived. In these maps, characteristic patterns of retardation and axis orientation were observed.
Conclusions: :
PS-OCT reveals polarizing properties of human anterior chamber tissues. FRC SD PS-OCT system is a powerful tool for polarization sensitive imaging of the complete anterior chamber in vivo.
Keywords: imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • optical properties