Characterization Of A Noninvasive, In Vivo, Microscopic Hyperspectral Imaging System For Microvascular Visualization.

Abstract

Instrumentation with clinical implications for imaging the human oculus was developed, based upon the hyperspectral imaging modality. The novel, non invasive, microscopic multi-modal hyperspectral imaging system, which operates in the visible as well as near infrared region, is capable of generating images illustrating spatial distribution of oxyhemoglobin contributions. The device principally comprises of a liquid crystal tunable filter and a focal plane array detector that is integrated to the slit lamp microscope. A proof of principle clinical study involving ten healthy subjects was undertaken to image the microvascular structure within the dermal tissue within the near infrared region, however these results are not validated. The spectral range used in the study was 650 - 1050nm, with a spectral resolution of 5nm, magnification of 10X to obtain a 35 ms acquisition time and a spatial resolution of 0.054 mm at binning of 1 x 1. The successful dermal microvascular study paved way for imaging the human eye using the visible region, wherein the anterior scleral surface was visualized in seven healthy subjects to spatially map the oxyhemoglobin contributions in the microvasculature perfusing the sclera. The spectral range used in the human eye study was 520 - 602nm, with a spectral resolution of 2nm, magnification of 10X to obtain a 5 ms acquisition time and a spatial resolution of 0.038 mm at binning of 2 x 2.