US 5,422,730 AGranted

Automated optical detection of tissue perfusion by microspheres

OwnerClyde H. Barlow, Jeffrey J. Kellyinventors

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Abstract

A method and apparatus for optical detection and imaging of regional circulatory flow in biological tissues for research purposes. An animal or plant organ is perfused with a saline suspension of colored and/or fluorescent microspheres. The organ is excised and fixed in the form of a specimen block for mounting in a microtome or other suitable apparatus. Under automatic control of a microcomputer equipped with a frame grabber, a surface layer of the block is removed, the resulting new exposed surface of the block receives a flash of illumination from a light source, and light reflected by colored microspheres or, alternatively, light emitted by fluorescent microspheres, is detected by a CCD video camera aimed at the block. Also under microcomputer control, light filters having suitable light bandpasses are interposed between the light sources and the block, and between the block and the camera. Video signals are converted by the microcomputer into position coordinates with associated optical intensities from which regional circulatory flow is computed and displayed on a monitor.

Claims21

Dependent claims

Apparatus for detection, storage and display of the location of fluorescent, phosphorescent or colored microspheres within a biological tissue block, comprising:

(a) means for the sequential removal of surface layers from the block thereby creating a sequence of exposed faces thereof;
(b) one or more light sources to illuminate each exposed face of the block;
(c) a video camera for receiving a reflected light, phosphorescence, or fluorescence emission image of each of a series of exposed faces of the block and converting the images into electrical signals;
(d) one or more excitation filters for selecting a desired frequency band of light illuminating each exposed face of the block;
(e) one or more detection filters for selecting a desired frequency band of light entering the video camera;
(f) a digital computer equipped with a frame grabber and connected to the video camera for receiving electrical signals therefrom and performing data acquisition, reduction and storage;
(g) a first digital computer software program for data reduction and storage;
(g) a second digital computer software program for calculating circulatory flow in regions of the tissues of the tissue block;
and
(h) a third computer software program for displaying on a digital computer video monitor a visual representation of circulatory flow in the tissue of the tissue block.

7 more elements

Dependencies are inferred from the claim text.