Advanced functional and intraoperative ophthalmic optical coherence tomography imaging

Abstract

Optical coherence tomography (OCT) is a non-contact, non-invasive imaging technique that uses optical interferometry to generate high-resolution, depth-resolved images of tissue in vivo. Ophthalmologists now use commercial OCT systems as a standard diagnostic instrument for imaging the retina to detect or monitor pathologies. However, prototype OCT research instruments exceed commercial systems in terms of faster imaging speeds and higher resolutions. Finding applications for these improvements will improve clinical utility for future OCT systems. This thesis describes the design and use of an ultrahigh resolution spectral domain OCT system for detecting the photoreceptor changes during flash stimulus and an ultrahigh resolution swept source OCT system for use in eye surgery. The ultrahigh axial resolution of our system enabled visualization of thickness changes in the outer retinal layers after flash stimulus and subsequent dark adaptation. This finding could be used as a marker for photoreceptor health in retinal diseases that influence dark adaptation such as age-related macular degeneration. In the operating room, the ultrahigh speed system attaches to the operating microscope to share the surgeon's view and provide depth-resolved information that is not possible with the standard surgeon's stereoscopic view. This allows for imaging during surgical procedures and the ultrahigh speed enables acquisition of dense, widefield data sets as well as rapid volume acquisition to generate 3D visualizations in time. These data sets will enable 3D planning of procedures, assessment of outcomes before leaving the operating room, and feedback for surgical procedures.