Sterilizable, disposable optical scattering reference medium and container assembly

• US 4,322,164 A
• Filed: 06/25/1979
• Issued: 03/30/1982
• Est. Priority Date: 10/18/1976
• Status: Expired due to Term

• Current Assignee: Oximetrix, Inc.
• Original Assignee: Oximetrix, Inc.
• Inventors: Sperinde, John M., Shaw, Robert F.
• Primary Examiner(s): Michell, Robert W.
• Assistant Examiner(s): Jaworski, Francis J.
• Application Number:
  US06/052,065
• Time in Patent Office: 1,009 Days
• Field of Search: 128/6, 128/632, 128/634, 128/633, 128/, 250/227, 250/252, 350/105, 350/96.2-96, 350/22, 362/32, 356/665, 356/666, 356/39-42, 356/243
• US Class Current: 356/243.8
• CPC Class Codes: A61B 2560/0233 Optical standards
• CPC Class Codes: A61B 5/1459 invasive, e.g. introduced into the body by a catheter A61B5/1464 takes precedence
• CPC Class Codes: A61B 5/1495 Calibrating or testing of in-vivo probes
• CPC Class Codes: G01N 21/4785 Standardising light scatter apparatus; Standards therefor

Abstract

An optical scattering reference medium is formed of a plurality of scattering particles substantially uniformly dispersed in a substantially compliant, non-compressable transparent solid medium which is selectively positionable against the distal end of an optical catheter for use therewith within a sterilizable disposable package for performing repeatable photometric measurements to standardize the performance of the photometric measuring instrument.

Claims

1. Apparatus for providing a calibration reference for use with a light guide that cooperates with a photometric measuring device in making light intensity measurements at a number of selected wavebands, the apparatus comprising (a) a plurality of light-scattering particles substantially uniformly dispersed throughout a solid medium that has a substantially incompressible body which is sufficiently compliant at its surface for intimate physical contact with the end of the light guide;

and (b) means for urging and maintaining intimate physical contact between the end of the light guide and the compliant surface.

2. Apparatus as in claim 1 wherein said medium is sufficiently transparent at the selected wavebands of a photometric measuring device to transmit light that is scattered from within the body to the compliant surface in contact with the light guide.

3. Apparatus as in claim 1 for providing a light-scattering reference means for operation with a photometric measuring device which measures oxygen saturation of blood, wherein the light-scattering particles have dimensions within the range of from about 0.02 to 20 microns.

4. Apparatus as in claim 1 for providing a light-scattering reference means for operation with a photometric measuring device which measures oxygen saturation of blood, wherein the density of light-scattering particles within said medium ranges from about 0.001% to 1.0% by weight.

5. Apparatus as in claim 1 wherein said light-scattering particles are materials selected from the group consisting of oxides, carbonates, sulphates of titanium, magnesium, calcium and barium.

6. An assembly adapted for use with an optical catheter which has a light guide and which is capable of cooperating with a photometric measuring device in making light intensity measurements comprising:

clamp means disposed to receive the optical catheter near an end of the catheter and to restrain the optical catheter against movement in a direction substantially along the length thereof,

resilient means disposed to urge a reference surface into intimate physical engagement with the end of the light guide of the optical catheter restrained by the clamp means for providing a medium for reference measurements at the end of the light guide, and

actuating means supported on said clamp means for causing said clamp means to restrain the optical catheter received by said clamp means and to cause said resilient means to urge said reference surface into engagement with the end of the optical catheter received by said clamp means in response to manual manipulation of said actuating means.

7. Apparatus for providing a calibration reference for use with a light guide that cooperates with a photometric measuring device in making light intensity measurements at a number of selected wavebands, the apparatus comprising (a) a plurality of light-scattering particles substantially uniformly dispersed throughout a solid medium that has a substantially imcompressible body which is sufficiently compliant at its surface for intimate physical contact with the end of the light guide;

and (b) means for urging and maintaining intimate physical contact between the end of the light guide and the compliant surface, said means for urging and maintaining comprising (i) clamp means disposed to restrain said light guide against movement in a direction substantially along the length of the light guide; and

(ii) resilient means disposed to urge said compliant surface into intimate physical engagement with the end of said light guide when the light guide is clamped by said clamp means, said resilient means urging with a force which is substantially constant and reproducible in said assembly and in each assembly within a population of such assemblies.

8. An assembly for use with an optical catheter which has a light guide and which is capable of cooperating with a photometric measuring device in making light intensity measurements comprising

apparatus for providing a reference means for operation with a photometric measuring device which operates on radiation at selected wavebands, the apparatus including a plurality of light-scattering particles dispersed within a solid medium having a substantially incompressible body,

clamp means disposed to receive the optical catheter near an end of the catheter and to restrain the optical catheter against movement in a direction substantially along the length of the catheter,

resilient means disposed to urge a reference surface of said reference means into intimate physical engagement with the end of the light guide of the optical catheter restrained by said clamp means for providing a medium for reference measurements at the end of the light guide,

housing means disposed to receive the optical catheter near one end of the catheter and to support said clamp means near said one end to selectively engage the optical catheter received by the housing means,

said housing means supporting said resilient means for movement relative thereto to selectively engage said reference surface with the end of the optical catheter received by said housing means, and

actuating means supported on said housing means for actuating said clamp means to restrain the optical catheter received by said housing means and to actuate said resilient means to resiliently urge said reference surface into intimate physical engagement with the end of the optical catheter received by said housing means in response to manual manipulation of said actuating means.

9. In combination with the assembly of claim 8:

an optical catheter having a light guide extending therethrough from a distal end to a proximal end thereof, said optical catheter having its distal end received by the assembly and having a proximal end which forms an optical coupler;

inner enclosure means disposed about the assembly having the optical catheter to form an enclosure thereabout with a region thereof having a flexible portion adjacent the actuating means to facilitate manual manipulation of the actuating means supported on said housing means, the inner enclosure means having an opening through which the proximal end and optical coupler formed thereon protrude; and

outer enclosure means disposed about the inner enclosure means having the optical coupler and forming an enclosure thereabout.

10. An apparatus for providing an optical reference element adapted for use with a light guide comprising,

clamp means disposed to restrain said light guide against movement in a direction substantially along the length thereof,

resilient means disposed to urge the optical reference element into intimate physical engagement with the end of said light guide when said light guide is restrained by the clamp means, and

actuating means connected to said clamp means for causing said clamp means to restrain said light guide and for causing said resilient means to urge said reference element into intimate physical engagement with said light guide in response to manual manipulation of said actuating means.

11. Apparatus for providing a calibration reference for use with a light guide that cooperates with a photometric measuring device in making light intensity measurements at a number of selected wavebands, the apparatus comprising (a) a plurality of light-scattering particles substantially uniformly dispersed throughout a solid medium that has a substantially incompressible body which is sufficiently compliant at its surface for intimate physical contact with the end of the light guide;

and (b) means for urging and maintaining intimate physical contact between the end of the light guide and the compliant surface, said means for urging and maintaining comprising (i) clamp means adapted to restrain the light guide against movement in a direction substantially along the length thereof, and (ii) resilient means adapted to urge the compliant surface of said incompressible body against the end of the light guide to achieve intimate physical engagement therewith.

12. Apparatus for providing a calibration reference for use with a light guide that cooperates with a photometric measuring device in making light intensity measurements at a number of selected wavebands, the apparatus comprising (a) a plurality of light-scattering particles substantially uniformly dispersed throughout a solid medium that has a substantially incompressible body which is sufficiently compliant at its surface for intimate physical contact with the end of the light guide;

and (b) means for urging and maintaining intimate physical contact between the end of the light guide and the compliant surface, said means for urging and maintaining comprising (i) clamp means disposed to restrain said light guide against movement in a direction substantially along the length of the light guide; and

(ii) resilient means disposed to urge said compliant surface into intimate physical engagement with the end of said light guide when the light guide is clamped by said clamp means, said resilient means urging with a force which is substantially constant and reproducible in said assembly and in each assembly within a population of such assemblies; and

(c) actuating means connected to said clamp means for causing said resilient means to urge said compliant surface of said incompressible body into intimate physical engagement with the end of the light guide in response to manual manipulation of said actuating means.

13. A method for calibrating a photometric measuring device having a light guide comprising the steps of:

(a) selecting a calibration reference comprising a plurality of light-scattering particles substantially uniformly dispersed throughout a solid medium that has a substantially incompressible body which is sufficiently compliant at its surface for intimate physical contact with the end of the light guide; and

(b) urging and maintaining intimate physical contact between the end of the light guide and the compliant surface during calibration of the photometric measuring device.