Apparatus for determining the concentration of a fluorescent material in an eye

• US 4,412,543 A
• Filed: 04/09/1981
• Issued: 11/01/1983
• Est. Priority Date: 04/09/1981
• Status: Expired due to Term

• Current Assignee: Ocumetrics, Inc.
• Original Assignee: Xanar Incorporated
• Inventors: Myers, Robert E., Vassiliadis, Arthur, Brewer, Michael H.
• Primary Examiner(s): Cohen, Lee S.
• Assistant Examiner(s): Sykes, Angela D.
• Application Number:
  US06/248,881
• Time in Patent Office: 936 Days
• Field of Search: 128/645-649, 128/745, 128/303 R, 128/303.1, 128/633-634, 128/664-665, 356/152-153, 356/337-338, 356/340, 356/343, 351/6, 351/9, 351/14, 351/213, 73/DIG. 11, 372/23
• US Class Current: 600/321
• CPC Class Codes: A61B 3/1241 specially adapted for observation of ocular blood flow, e.g. by fluorescein angiography
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/1455 using optical sensors, e.g. spectral photometrical oximeters

Abstract

A fluorophotometer for determining the concentration of a fluorescent material in an eye, including a light source producing a beam of light traversing a path in the eye to excite the material to emit fluorescence, optics for imaging the path and fluorescence at a detecting plane, a linear photodiode array at the detecting plane for detecting the fluorescence along the path, and a microprocessor for collecting data from the array and producing information of the concentration of the fluorescent material.

Claims

1. An apparatus for determining the concentration of an administered fluorescent material at a plurality of locations in an eye which comprises:

(a) light source means for exciting the fluorescent material along a path length in the eye to emit fluorescence; and

(b) means for imaging fluorescence responsive to said excitation simultaneously at a plurality of locations along said path length.

2. The apparatus according to claim 1 wherein said means for imaging further includes optical means for forming an image of the fluorescence along said path length and detection means for detecting substantially simultaneously fluorescence at a plurality of discrete locations along said path length.

3. In a fluorophotometer for measuring the concentration of a fluorescent substance such as fluorescein in the eye of a subject to whom a quantity of such substance was previously administered of the type having a source of light to emit a beam for exciting said fluorescein to allow measurement of fluorescein concentration in the eye, the improvement characterized by:

(a) stationary optical means for imaging fluorescence simultaneously along a path length within the eye; and

(b) detecting means for detecting said optically imaged path length and for generating signals representative of fluorescent concentration at a plurality of locations along said imaged path length.

4. Apparatus according to claim 3 wherein said detecting means comprises a linear photodiode array having a plurality of photodiode sensor elements.

5. The apparatus according to claim 4 wherein said detecting means further comprises:

(a) means for scanning said linear photodiode array and for generating analog signals representing the fluorescent concentration detected by each of said sensor elements;

(b) means for converting the analog signals to digital data; and

(c) microprocessor means for generating information identifying the concentration of the fluorescent substance in response to the digital data.

6. In a fluorophotometer for determining the concentration of fluorescence in an eye of the type where the fluorescence is excited with a beam of light adapted to enter and transverse a path in the eye, the beam of light being produced by a source of light the improvement comprising:

(a) a self-contained head being connectable to the source of light, said head including

(i) stationary optical means for imaging simultaneously fluorescence emitted along the entire path at a detecting plane,

(ii) a linear photodiode array, positioned at the detecting plane, for detecting the fluorescence emitted along the path and for generating analog signals representing the detected fluorescence,

(iii) an analog-to-digital converter connected to said linear photodiode array, said converter converting the analog signals to digital data and generating a status signal at the end of each conversion, said linear photodiode array being reset in response to the status signal, and

(iv) means for clocking said linear photodiode array to start the scanning and for clocking said converter to start the conversion; and

(b) programmable microprocessor means, coupled to said self-contained head, for generating information identifying the concentration of the fluorescence in response to the digital data.