WO1990007907A1 - Dispositif de mesure oximetrique a infrarouge - Google Patents

Dispositif de mesure oximetrique a infrarouge Download PDF

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Publication number
WO1990007907A1
WO1990007907A1 PCT/US1990/000181 US9000181W WO9007907A1 WO 1990007907 A1 WO1990007907 A1 WO 1990007907A1 US 9000181 W US9000181 W US 9000181W WO 9007907 A1 WO9007907 A1 WO 9007907A1
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WO
WIPO (PCT)
Prior art keywords
light
brain
organ
oximetry
metabolic activity
Prior art date
Application number
PCT/US1990/000181
Other languages
English (en)
Inventor
Robert J. Hariri
Jamshid B. G. Ghajar
Fathali Ghahremani Ghadjar
Original Assignee
Neurodynamics, Inc.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Neurodynamics, Inc. filed Critical Neurodynamics, Inc.
Publication of WO1990007907A1 publication Critical patent/WO1990007907A1/fr

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Classifications

    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00—Measuring for diagnostic purposes; Identification of persons
    • A61B5/145—Measuring characteristics of blood in vivo, e.g. gas concentration, pH value; Measuring characteristics of body fluids or tissues, e.g. interstitial fluid, cerebral tissue
    • A61B5/1455—Measuring characteristics of blood in vivo, e.g. gas concentration, pH value; Measuring characteristics of body fluids or tissues, e.g. interstitial fluid, cerebral tissue using optical sensors, e.g. spectral photometrical oximeters
    • A61B5/1459—Measuring characteristics of blood in vivo, e.g. gas concentration, pH value; Measuring characteristics of body fluids or tissues, e.g. interstitial fluid, cerebral tissue using optical sensors, e.g. spectral photometrical oximeters invasive, e.g. introduced into the body by a catheter
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00—Measuring for diagnostic purposes; Identification of persons
    • A61B5/40—Detecting, measuring or recording for evaluating the nervous system
    • A61B5/4058—Detecting, measuring or recording for evaluating the nervous system for evaluating the central nervous system
    • A61B5/4064—Evaluating the brain

Definitions

  • the invention relates to methods and devices which are either mounted upon the dural membrane of a human brain, or within the brain itself, for measuring blood flow to the brain by infrared oximetry techniques.
  • Head trauma remains one of the most common causes of death and disability in the United States and Western Europe. It is responsible for an annual cost to society for hospitability, rehabilitation and job related losses exceeding 10 billion dollars; the costs in terms of human suffering are immeasurable.
  • Current therapy directed at the management of closed head injury is based largely on empirical methods to control elevated intracranial pressure (ICP) in an attempt to preserve blood flow to the brain and reduce the likelihood of brain stroke.
  • ICP intracranial pressure
  • the effect of intracranial hypertension on cerebrovascular hemodynamics is still poorly understood. Yet there exists strong clinical and experimental data which supports the hypothesis that elevated intracranial pressure impairs the normal dilator response of cerebral arterioles to undergo compensatory dilation with elevation in arterial carbon dioxide (pCO ) .
  • vasomotor dysrequlation has been definitively linked to post-traumatic brain injury.
  • the current therapeutic standards for reducing intracranial hypertension namely hyperventilation and osmotic diuresis, represent areas where reduction of ICP may be gained at the cost of effective tissue perfusion and oxygenation. It is unclear whether reduction of arterial pCO. with concomitant arteriolar vasoconstriction provides decreased ICP without- sacrificing overall cerebral perfusion and if, in fact, this may contribute to ultimate neuronal cell loss following injury.
  • Osmotic diuresis in the presence of a compromised blood brain barrier may result in extravasation of osmotically active particles into the parencyma where they contribute to intracranial "mass effect" when normovolemia is returned.
  • osmodiuresis impairs icrocirculatory hemodynamics thereby reducing regional perfusion in the injured brain.
  • the purpose of the present invention is to provide a method to measure accurately the efficiency of oxygen delivery to the brain by use of an infrared oximetric device applied directly to the brain.
  • One infrared oximetry device described is in the form of a intraventricular catheter.
  • a second infrared oximetry device is in the form of a cylindrical carriage or bolt which is screwed into the skull and mounted directly upon the dural membrane.
  • a third infrared oximetry device is in the form of a flexible, flat and elongated circuit board which can be placed between the dural membrane and the inner table of the skull. All three devices are invasive in nature. By “invasive” we mean that the devices are designed to be applied immediately adjacent to or inserted inside a body organ such as the brain.
  • An example of such a procedure would be the drilling of an orifice or burr hole through the skull so that the invasive device may be placed next to the dural membrane or through the membrane and into the brain.
  • the drill may be used with a drill guide as described in U.S. Patent No. 4,821,716 and Application No. 113,580, so as to allow for the controlled and properly aligned perforation of the cranium. If a catheter is to be inserted into the brain, correct placement can be facilitated by a guide assembly such as that disclosed in U.S. Patent No. 4,613,324.
  • the invasive device utilizes infrared technology to measure oxygenated and deoxygenated hemoglobin; and is composed of a light emitting diode source and a group of photodetectors designed to produce a signal when stimulated by light in specific ranges of the infrared spectrum. Since oxygenated and deoxygenated hemoglobin absorb infrared light in two distinct portions of the spectrum, relative reflected light of a known source intensity can be calculated to quantitatively determine the relative amounts of each infrared absorbing substance. The signal can be modified and enhanced to provide information as to the ratio of oxygenated to deoxygenated blood in the microcirculatory bed illuminated by the LED source.
  • Measurement of the oxygenated status of brain blood flow allows continuous monitoring of brain oxygen extraction from the blood. At a steady brain metabolic activity rate, a drop in the oxygenated hemoglobin saturation signal would indicate increased extraction of oxygen from the blood and therefore a lower brain blood flow value. This measurement directly affects the management of a patient, for example, the patient in the intensive care unit being sustained on a respirator following brain injury. A decrease in the ratio of oxygenated to deoxygenated hemoglobin in the cerebral cortex under study would indicate a situation of inadequate perfusion, whether due to alteration in cerebral oxygen demand (a metabolic change) , or alteration in cerebral blood flow.
  • the catheter to be inserted within the brain also may include other devices for measuring parameters of the body related to other metabolic activities.
  • the brain oximetry catheter can be combined with thermistors to measure blood flow, a pressure sensor to measure internal pressure, and an electrode for electroencephalography. In this way an assortment of body functions may be measured by the same device to ensure that the doctor can determine the proper therapeutic regimen for the patient.
  • peripheral transmission oximetry e.g. finger
  • brain reflectance oximetry By modifying and enhancing peripheral transmission oximetry, (e.g. finger) which is commercially available, with brain reflectance oximetry, the physician can judge whether the source of decrease in brain oxygenation is a cardiorespiratory or a cerebral event and take the appropriate clinical steps to address the deficit.
  • FIG. 1 is a perspective view of a catheter in accordance with one embodiment of the invention
  • FIG. 2 is an expanded view of a portion of the catheter of FIG. 1 illustrating thermistor and oximetry devices thereon;
  • FIG. 3 is an expanded view of the catheter of FIG. 1 showing the relative location of drainage apertures, thermistors, oximetry devices, and pressure sensors thereon;
  • FIG. 4 is an axial cross sectional view of the catheter taken along the plane 4—4 of FIG. 3 illustrating the internal lumens;
  • FIG. 5 is a schematic illustration of the signal converter display when connected to a patient
  • FIG. 6 is a schematic illustration of the oximetry bolt according to another embodiment of the invention.
  • FIG. 7 is an expanded view of the oximetry bolt
  • FIG. 8 is the bottom view of the oximetry bolt illustrating the position of the oximetry light source and receiver
  • FIG. 9 is a schematic illustration of the flexible and flat oximetry board device according to a third embodiment of the invention.
  • FIG. 10 is a bottom view of the flexible, flat elongated oximetry board device.
  • FIG. 11 is a side view of the flexible, flat elongated oximetry board device.
  • the invention consists of a catheter 10 which is inserted into the human brain.
  • FIG. 1 depicts an external view of the catheter 10.
  • Barium markings are placed along the catheter at 4, 5, 6 and 10 cm from the tip.
  • Catheter shaft 12 contains holes 14 for body fluid drainage. These twelve drainage holes near the distal tip are angled about 30°. from the axis of the catheter.
  • a particularly preferred catheter design is disclosed in U.S. Patent No. 4,784,638, the disclosure of which is expressly incorporated herein by reference thereto.
  • the present invention contemplates multi- lumen catheters of similar configuration.
  • Thermistor units 16 and 18 are capable of measuring the blood flow to the organ being studied using standard thermodilution techniques.
  • the thermistor can be located anywhere along the length of the catheter that is implanted in the organ.
  • the oximetry LED source 30 and the oximetry receiver 34 are located away from the catheter tip and 180° apart from each other on the circumference of the catheter so that direct light transmission cannot occur.
  • Oximetry LED source 30 sends signals to oximetry receiver 34, which measures the amount of reflected light in a specific portion of the infrared spectrum representing the amount of oxygenated and deoxygenated hemoglobin.
  • Pressure sensor 40 positioned near the catheter tip measures the pressure within the organ.
  • Electroencephalographic electrode 49 positioned away from the catheter tip monitors electrical activity in the tissue.
  • Cable 22 connects the wires from the electronic components in catheter tube 12 to the electric connector 20.
  • oximetry LED source 30 which is controlled by the signal converter 70, through wires 32, sends infrared light waves into the surrounding tissue.
  • the light waves correspond to frequencies which are reflected from the blood constituents that are to be measured.
  • Oximetry receiver 34 creates electrical signals corresponding to the amount of each light frequency detected and sends the signals to a signal converter for display and recording via cable 22.
  • the catheter is inserted into the brain so as to place the oximetry LED source 30 and the electroencephalograph electrode 49 in the grey matter of the brain (cortical mantel) .
  • the oximetry receiver 34 will contact the surface of the grey matter.
  • the temperature of fluid in chamber 24, when in equilibrium with the surrounding blood, is measured by thermistor 28.
  • the measurement of the fluid temperature in equilibrium determines the temperature of the blood.
  • the fluid in chamber 24 is exchanged with a cooled fluid through tube 26.
  • the thermistor 28 monitors the initial drop in temperature and then the subsequent increase in temperature as the cooled fluid equilibrates to the original temperature of the blood. The rate at which this equilibration occurs corresponds to the rate of blood flow to the adjacent tissue.
  • Wires 38 run from the thermistor 28 to a signal converter where the temperature readings are converted to blood flow measurements according to the formula:
  • T temperature
  • FIG. 3 illustrates a view partially in section of the catheter
  • FIG. 4 illustrates a cross sectional view along plane 4-4.
  • the catheter is composed of silicone, molded to a diameter of 4 millimeters and is 15 centimeters in length.
  • the catheter is segmented into various lumens.
  • the main lumen 42 with a diameter of 1.5 - 1.7 mm is surrounded by a .25 mm thick barium impregnated silicone wall.
  • the inner channel of the main lumen is used for draining cerebral spinal fluid.
  • the barium impregnated silicone wall is appropriately radio-opaque so that the position of the catheter within the brain may be monitored by x-ray.
  • the oximetry/thermistor lumen 44 contains the oximetry source 30 and receiver 34 as well as the thermistor units 16 and 18.
  • Pressure lumen 46 contains pressure sensor 40.
  • Electroencephalogram lumen 48 contains EEG sensor 49.
  • FIG. 5 illustrates the connections between the catheter 10 and the signal converter 70.
  • the electronic components of catheter 10 have wires running into cable 22 which is terminated by end connector 20. End connector 20 fits into socket 52 which is located on signal converter 70.
  • Signal converter 70 contains key pad 64, disk drives 62 and display screen 82. Display screen 82 displays graphs of various blood parameters denoted on FIG. 5 by 74.
  • Socket 54 located on signal converter 70 is the connector for a peripheral oximetry device such as item 116 of FIG. 6.
  • Bolt 102 is screwed into the skull 200 of the patient, and mounted on the dural membrane 210 of the brain 220.
  • Bolt 102 contains oximetry LED source 106 and oximetry receiver 108.
  • Oximetry LED source 106 emits light of certain frequencies into the brain 220. These light waves are reflected from certain constituents of blood in the brain and are detected by oximetry receiver 108.
  • the signal from oximetry receiver 108 is sent to signal converter 110 through wire 104.
  • Signal converter 110 converts the signal into a desirable measurement and displays it on screen 112.
  • the oximetry LED source is controlled by the signal converter through wire 103. Wires 103 and 104 terminate at connector 124 which fits into socket 132 located on signal converter 110.
  • the graph of screen 112 is compared to peripheral oximetry from peripheral oximetry device 116 which uses transmission oximetry rather than reflectance oximetry as is used by brain oximetry bolt 102.
  • Peripheral oximetry device 116 has an LED source 120 controlled by the signal converter 110 through wire 117 and an oximetry receiver 122 which sends signals to the signal converter 110 through wire 118.
  • the signal from the oximetry receiver 122 is converted by the signal adaptor 110 into a measurement which is displayed on screen 114.
  • Wires 117 and 118 terminate at connector 126 which fits into socket 134 located on signal converter 110.
  • FIG. 7 provides an expanded view of the bolt 102.
  • the bolt is made of stainless steel with side torque pins 107 to facilitate the screwing of the bolt into the skull.
  • the bottom of the bolt has 2/16 inch self tapping threads 109.
  • the oximetry LED source 106 and oximetry receiver 108 are located at the bottom of the bolt 102 so that they may be positioned next to the du
  • FIG. 8 provides a bottom view of the bolt 102 showing the oximetry LED source 106 and oximetry receiver 108 attached to ceramic microprocessor chips.
  • the source 106 and receiver 108 are separated by an opaque wall 111 which serves as a barrier or means to prevent direct light transmission from source 106 to detector 108.
  • FIGS. 9-11 illustrate a third embodiment of the invention.
  • the flat, flexible and elongated circuit board 202 is placed through a burr hole 201 of the skull 200.
  • the light source 205 and photodetector 206 mounted at the tip of the board are placed between the dural membrane and the inner table of the skull to assure maximum contact and to measure the oxygenation of blood in the grey matter of the brain.
  • the light source 205 and photodetector 206 are connected by cable 203 to a signal converter, a visual display screen and a data storage device which are not shown.
  • FIG. 10 provides an expanded top view of the flat, flexible and elongated circuit board.
  • a light source 205 such as a LED, and a photodetector 206 are mounted on the tip of the circuit board and are connected by cable 203 to a signal converter for the measurement of the ratio of oxygenated to deoxygenated blood in the brain.
  • the electrical connections 207 to the light source and photodetector are encapsulated by a polymer 204 to prevent fluid interference with the proper operation of the device.
  • the light source and photodetectors themselves are also encapsulated and placed near the surface of the flexible circuit board.
  • the light source is mounted at an angle with respect to the photodetector so as to minimize interference in the detected signal by direct transmission of light from source 205 and thus optimize the detection of light reflected from brain tissue.

Abstract

Procédé et dispositif oximétrique par réflectance d'infrarouge permettant de mesurer le rapport entre l'hémoglobine oxygénée et l'hémoglobine désoxygénée dans la circulation des tissus du cerveau d'un sujet. Un mode de réalisation consiste en un cathéter intraventriculaire (12) qui contient une source oximétrique à infrarouge (30) et un récepteur oximétrique (34). Un second mode de réalisation consiste en un boulon (106) qui est vissé dans le crâne et monté sur la membrane durale. Un troisième mode de réalisation est une plaque de circuit plate et flexible (201) qui peut être placée entre la membrane durale et la table interne du crâne. Ces dispositifs contiennent une source oximétrique à infrarouge et un récepteur oximétrique. Des signaux provenant du récepteur oximétrique sont utilisés pour représenter graphiquement le pourcentage de certains constituants sanguins à mesurer, permettant ainsi de contrôler l'activité métabolique du sujet.
PCT/US1990/000181 1989-01-10 1990-01-09 Dispositif de mesure oximetrique a infrarouge WO1990007907A1 (fr)

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Application Number Priority Date Filing Date Title
US29541789A 1989-01-10 1989-01-10
US295,417 1994-08-25

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Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0413588A2 (fr) * 1989-08-17 1991-02-20 Critikon, Inc. Capteur d'oxygène épidural
US5320634A (en) * 1990-07-03 1994-06-14 Interventional Technologies, Inc. Balloon catheter with seated cutting edges
EP0692948A1 (fr) * 1993-03-05 1996-01-24 SAHAGEN, Armen, N. Sonde de controle d'un milieu fluide
WO2000013576A1 (fr) * 1998-09-09 2000-03-16 U.S. Army Institute Of Surgical Research Canule nasopharyngee avec capteur de sphygmo-oxymetre a reflectance
US6144867A (en) * 1998-09-18 2000-11-07 The United States Of America As Represented By The Secretary Of The Army Self-piercing pulse oximeter sensor assembly
US6253098B1 (en) 1998-09-09 2001-06-26 The United States Of America As Represented By The Secretary Of The Army Disposable pulse oximeter assembly and protective cover therefor
US6256524B1 (en) 1998-09-09 2001-07-03 The United States Of America As Represented By The Secretary Of The Army Pulse oximeter sensor combined with a combination oropharyngeal airway and bite block
US6263223B1 (en) 1998-09-09 2001-07-17 The United States Of America As Represented By The Secretary Of The Army Method for monitoring arterial oxygen saturation
US6470200B2 (en) 2000-02-11 2002-10-22 The United States Of America As Represented By The Secretary Of The Army Pacifier pulse oximeter sensor
EP1547515A1 (fr) * 2003-12-22 2005-06-29 Barts and The London National Health Service Trust Sphygmo-oxymètre avec cathéter à fibre optique
CN108143426A (zh) * 2017-12-26 2018-06-12 成都拓蓝医疗技术有限公司 脑组织血氧饱和度精准监测传感器及其监测方法
US10028682B2 (en) 2012-10-12 2018-07-24 University Of Virginia Patent Foundation Oxidation measurement system and related method thereof

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US3605726A (en) * 1969-04-14 1971-09-20 Bryn T Williams Flexible,extra vascular electromagnetic blood flow probe
US3796213A (en) * 1970-09-18 1974-03-12 F Stephens Perfusion monitor
US4223680A (en) * 1977-06-28 1980-09-23 Duke University, Inc. Method and apparatus for monitoring metabolism in body organs in vivo
US4485820A (en) * 1982-05-10 1984-12-04 The Johns Hopkins University Method and apparatus for the continuous monitoring of hemoglobin saturation in the blood of premature infants
US4700708A (en) * 1982-09-02 1987-10-20 Nellcor Incorporated Calibrated optical oximeter probe
US4739771A (en) * 1986-02-20 1988-04-26 Kim Manwaring Thermal method and apparatus for measuring organ blood perfusion
US4784150A (en) * 1986-11-04 1988-11-15 Research Corporation Surgical retractor and blood flow monitor

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3605726A (en) * 1969-04-14 1971-09-20 Bryn T Williams Flexible,extra vascular electromagnetic blood flow probe
US3796213A (en) * 1970-09-18 1974-03-12 F Stephens Perfusion monitor
US4223680A (en) * 1977-06-28 1980-09-23 Duke University, Inc. Method and apparatus for monitoring metabolism in body organs in vivo
US4485820A (en) * 1982-05-10 1984-12-04 The Johns Hopkins University Method and apparatus for the continuous monitoring of hemoglobin saturation in the blood of premature infants
US4700708A (en) * 1982-09-02 1987-10-20 Nellcor Incorporated Calibrated optical oximeter probe
US4739771A (en) * 1986-02-20 1988-04-26 Kim Manwaring Thermal method and apparatus for measuring organ blood perfusion
US4784150A (en) * 1986-11-04 1988-11-15 Research Corporation Surgical retractor and blood flow monitor

Non-Patent Citations (1)

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Title
MEDICAL INSTRUMENTATION, Vol. 16, No. 4, July-August 1982, (MORTARA); "Intracranial Pressure Monitoring in the Emergency Setting", 2 pages. *

Cited By (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0413588A2 (fr) * 1989-08-17 1991-02-20 Critikon, Inc. Capteur d'oxygène épidural
EP0413588A3 (en) * 1989-08-17 1991-10-23 Critikon, Inc. Epidural oxygen sensor
GR900100617A (en) * 1989-08-17 1991-12-30 Critikon Inc Epidural oxygen sensor
EP0651968A1 (fr) * 1989-08-17 1995-05-10 Critikon, Inc. Capteur d'oxygène épidural
US5320634A (en) * 1990-07-03 1994-06-14 Interventional Technologies, Inc. Balloon catheter with seated cutting edges
EP0702524A1 (fr) * 1993-03-05 1996-03-27 SAHAGEN, Armen, N. Sonde de controle d'un support fluide
EP0692948A4 (fr) * 1993-03-05 1998-12-30 Armen N Sahagen Sonde de controle d'un milieu fluide
EP0702524A4 (fr) * 1993-03-05 1998-12-30 Armen N Sahagen Sonde de controle d'un support fluide
EP0692948A1 (fr) * 1993-03-05 1996-01-24 SAHAGEN, Armen, N. Sonde de controle d'un milieu fluide
AU761841B2 (en) * 1998-09-09 2003-06-12 Government Of The United States Of America As Represented By The Secretary Of The Army Nasopharyngeal airway with reflectance pulse oximeter sensor
WO2000013576A1 (fr) * 1998-09-09 2000-03-16 U.S. Army Institute Of Surgical Research Canule nasopharyngee avec capteur de sphygmo-oxymetre a reflectance
US6253098B1 (en) 1998-09-09 2001-06-26 The United States Of America As Represented By The Secretary Of The Army Disposable pulse oximeter assembly and protective cover therefor
US6256524B1 (en) 1998-09-09 2001-07-03 The United States Of America As Represented By The Secretary Of The Army Pulse oximeter sensor combined with a combination oropharyngeal airway and bite block
US6263223B1 (en) 1998-09-09 2001-07-17 The United States Of America As Represented By The Secretary Of The Army Method for monitoring arterial oxygen saturation
US6266547B1 (en) 1998-09-09 2001-07-24 The United States Of America As Represented By The Secretary Of The Army Nasopharyngeal airway with reflectance pulse oximeter sensor
US6144867A (en) * 1998-09-18 2000-11-07 The United States Of America As Represented By The Secretary Of The Army Self-piercing pulse oximeter sensor assembly
US6470200B2 (en) 2000-02-11 2002-10-22 The United States Of America As Represented By The Secretary Of The Army Pacifier pulse oximeter sensor
EP1547515A1 (fr) * 2003-12-22 2005-06-29 Barts and The London National Health Service Trust Sphygmo-oxymètre avec cathéter à fibre optique
WO2005060825A1 (fr) * 2003-12-22 2005-07-07 Barts And The London Nhs Trust Sphygmo-oxymetre a catheter a fibres optiques
US10028682B2 (en) 2012-10-12 2018-07-24 University Of Virginia Patent Foundation Oxidation measurement system and related method thereof
CN108143426A (zh) * 2017-12-26 2018-06-12 成都拓蓝医疗技术有限公司 脑组织血氧饱和度精准监测传感器及其监测方法

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