Patent ID: 6909792

Claim:
A method of visually documenting historical changes in biological tissue, comprising the steps of: (a) obtaining a first image of a region of tissue; (b) obtaining pathological feature data for said region of tissue; (c) obtaining a second image of said region of tissue using a first level of resolution; (d) digitally storing said first and second images as digitized first and second images; (e) spatially adjusting at least one of said first and second digitized images to spatially register said images so that corresponding features in both images are mapped to corresponding positions, said spatially adjusting comprising: determining a coordinate transformation which produces at least a pre-determined degree of correlation between said first and second digitized images, and applying said coordinate transformation to at least one of said first and second digitized images, to align said images; said coordinate transformation determined by: applying coordinate transformations of scale, position and rotation to one of said first and second digitized images, to obtain a plurality of corresponding adjusted images, cross-correlating said adjusted images with one of said first and second digitized images, to produce a correlation output, and selecting a coordinate transformation which produces at least a defined correlation output from its corresponding adjusted image; said cross-correlating comprising: inputting said first and second images to an optical correlator, and reading said correlation output from an output of said optical correlator; (f) correlating said pathological feature data with said second image to define a historical region-of-interest (ROI) in said second image; (g) rescanning the defined ROI using a second level of resolution higher than said first level of resolution to obtain a third image; (h) spatially adjusting at least one of said historical and rescanned ROI images to spatially register said ROI images so that corresponding features in both images are mapped to corresponding positions; and (i) creating from said historical and rescanned ROI images a composite image which visually emphasizes temporal differences between said ROI images, thereby visually emphasizing historical changes between said historical and rescanned ROI images.