Endoscopic Optical Coherence Tomography of the Retina at 1310 nm Using Paired-Angle-Rotating Scanning

Marinko V. Sarunic¹, Shuo Han², Jigang Wu², Zahid Yaqoob², Mark Humayun³ and Changhuei Yang² 
 

1) Engineering Science, Simon Fraser University, Burnaby, BC, V5A 1S6

2) Electrical Engineering, California Institute of Technology, Pasadena, CA 91125

3) Doheny Eye Institute, University of Southern California, Los Angeles, CA 90033. 
 

Vitrectomy (removal of the vitreous humor) is an ophthalmic surgery required as a precursor to several posterior chamber procedures. Vitrectomy is commonly performed using an endoscopic vitreous cutter and fiber based light delivery for observation through a surgical microscope. Cross-sectional visualization of the retina and remnant vitreous layers during surgery using an external optical coherence tomography (OCT) scanner is impractical due to deformation in the shape of the eye and the cornea. We present a forward imaging probe with 820 mm outer diameter (21 gauge needle) for cross-sectional endoscopic OCT imaging during ophthalmic surgeries. The Paired-Angle-Rotating Scanner (PARS) OCT probe is based on angle polished gradient index (GRIN) lenses which are rotated about the optical axis. The scan pattern is determined by the angle between the GRIN lenses and the relative angular velocity. Endoscopic placement of the PARS-OCT probe tip near the retinal surface permits use of a longer wavelengt