Fluorescent infrared scanning-laser ophthalmoscope for three-dimensional visualization: automatic random-eye-motion...

Scanning-laser ophthalmoscope (SLO) technology has provided, among other possibilities, the potential for three-dimensional (3-D) visualization of anatomy in the posterior pole of the eye. The use of indocyanine green (ICG) as an infrared fluorescent marker of vasculature in combination with aninfrared SLO (the Heidelberg Retina Angiograph) is presented. Presently, two main factors among others discussed impede the visualization of 3-D structures in observed SLO data. Random eye motion between optical sections and (to a lesser degree) motion between raster scan lines prevent assessment of spatial orientation and connectivity of vasculature. Second, smear along the optic axis owing to the optics prevents accurate determination of vessel or lesion size and shape, especially for features spanning several optical sections. A novel, to our knowledge, deconvolution algorithm is described that automatically corrects for the poor axial (optical-sectioning) resolution of the SLO and for patient random eye motion during target fixation. Encouraging preliminary results are presented showing the usefulness of applying blind deconvolution toward improving the 3-D clarity of SLO data. Although clinical and medical research applications are broad, the specific medical sample selected shows the potential of examining microvascular 3-D morphology for diagnosis and treatment of choroidal tumors.