[go: up one dir, main page]

WO2002015782A1 - Hematometre pour doigt a application laterale - Google Patents

Hematometre pour doigt a application laterale Download PDF

Info

Publication number
WO2002015782A1
WO2002015782A1 PCT/US2001/041718 US0141718W WO0215782A1 WO 2002015782 A1 WO2002015782 A1 WO 2002015782A1 US 0141718 W US0141718 W US 0141718W WO 0215782 A1 WO0215782 A1 WO 0215782A1
Authority
WO
WIPO (PCT)
Prior art keywords
digit
emitter
detector
optical probe
thumb
Prior art date
Application number
PCT/US2001/041718
Other languages
English (en)
Inventor
Massi E. Kiani
Original Assignee
Masimo Corporation
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 Masimo Corporation filed Critical Masimo Corporation
Publication of WO2002015782A1 publication Critical patent/WO2002015782A1/fr

Links

Classifications

    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00—Measuring for diagnostic purposes; Identification of persons
    • A61B5/68—Arrangements of detecting, measuring or recording means, e.g. sensors, in relation to patient
    • A61B5/6801—Arrangements of detecting, measuring or recording means, e.g. sensors, in relation to patient specially adapted to be attached to or worn on the body surface
    • A61B5/6813—Specially adapted to be attached to a specific body part
    • A61B5/6825—Hand
    • A61B5/6826—Finger
    • 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 or pH-value ; Measuring characteristics of body fluids or tissues, e.g. interstitial fluid or cerebral tissue
    • A61B5/1455—Measuring characteristics of blood in vivo, e.g. gas concentration or pH-value ; Measuring characteristics of body fluids or tissues, e.g. interstitial fluid or cerebral tissue using optical sensors, e.g. spectral photometrical oximeters
    • A61B5/14551—Measuring characteristics of blood in vivo, e.g. gas concentration or pH-value ; Measuring characteristics of body fluids or tissues, e.g. interstitial fluid or cerebral tissue using optical sensors, e.g. spectral photometrical oximeters for measuring blood gases
    • A61B5/14552—Details of sensors specially adapted therefor
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00—Measuring for diagnostic purposes; Identification of persons
    • A61B5/68—Arrangements of detecting, measuring or recording means, e.g. sensors, in relation to patient
    • A61B5/6801—Arrangements of detecting, measuring or recording means, e.g. sensors, in relation to patient specially adapted to be attached to or worn on the body surface
    • A61B5/683—Means for maintaining contact with the body
    • A61B5/6838—Clamps or clips

Definitions

  • This invention relates in general to optical probes, and in particular to low-noise, disposable and reusable optical probes applied to the side of a digit. Description of the Related Art
  • Energy is often transmitted through or reflected from a medium to determine characteristics of the medium.
  • light or sound energy may be caused to be incident to the patient's body, and transmitted or reflected energy may be measured to determine information about the material through which the energy is passed. This type of non-invasive measurement is more comfortable for the patient and can be performed more quickly.
  • Non-invasive measurements of bodily functions are often performed with optical probes.
  • the optical probe is housed in an adhesive bandage, a reusable clip, a Velcro securing mechanism, or the like.
  • the optical probes are housed such that an emitter vertically opposes a detector over the nail of a digit, such as, for example, a finger or toe.
  • the optical path length is defined as the distance between the emitter and the detector, such as, for example, the thickness of the material through which the optical energy must pass before reaching the detector.
  • the conventional attachment of the emitter and the detector such that the optical path length is defined through the nail of the digit fails to optimize the volume through which perfusion may take place.
  • the placement of the emitter and the detector defines a volume of tissue through which some optical energy will pass, and it is the perfusion through that volume that is measured by the optical probe.
  • the perfusion is unnecessarily limited. The limited perfusion fails to optimize the eventual signal-to-noise ratio obtained. Similar to the erratic absorption of optical energy, lower signal- to- ⁇ oise ratios result in difficulty with signal interpretation.
  • one aspect of the present invention is to apply an optical probe to a digit along a horizontal plane, or from the side.
  • Such side-application dramatically decreases the chance of direct physical depression, thereby, reducing changes in optical path length.
  • side-application increases the volume through which perfusion can be measured, thereby advantageously increasing the signal-to-noise ratio.
  • Another aspect of the present invention is to apply the optical probe to the thumb of a patient.
  • Use of the thumb provides increased perfusion and potentially less motion.
  • the advantages of increased perfusion and less motion include a more stable signal having an increased signal-to- ⁇ oise ratio.
  • one aspect of the invention is a method for producing an optical probe for measuring at least one characteristic of a digit.
  • the method comprises positioning an emitter and a detector within an attachment mechanism such that the emitter and the detector substantially oppose one another along an axis substantially parallel to a nail portion of the digit when the attachment mechanism is attached to the digit.
  • Another aspect of the invention is a method of reducing a change in an optical path length caused by physical depression of a digit against an object.
  • the optical path length is defined between an emitter and a detector in an optical probe.
  • the method comprises attaching an emitter to a first side of a digit and attaching a detector to a second side of the digit.
  • a vertical axis of the digit is defined as perpendicular to a nail portion of the digit.
  • the first side and the second side substantially oppose one another and are approximately parallel to the vertical axis.
  • the housing for an optical probe used to noninvasively measure at least one characteristic of a digit.
  • the housing comprises a first portion configured to position an emitter along a first side of a digit, wherein the first side is substantially perpendicular to a nail portion of the digit.
  • the housing includes a second portion configured to position a detector along a second side, wherein the second side substantially opposes the first side.
  • the housing includes a third portion configured to position a flexible circuit within the housing, wherein the flexible circuit connects the emitter and the detector to an oximeter connector.
  • an optical probe that comprises an emitter configured to cause light energy incident to a patient's thumb, a detector configured to detect the light energy, a housing configured to position an emitter on a first side of the thumb and to position a detector on a second side of the thumb, wherein the first side substantially opposes the second side and both sides are substantially perpendicular with a plane of a thumbnail.
  • the optical probe also comprises a flexible circuit electrically connected to the emitter and the detector for communicating a drive signal to the emitter, and communicating a detected signal from the detector.
  • Another aspect of the invention is a method of applying an optical probe to a patient's thumb, the method comprising applying an optical probe to a patient's thumb such that an emitter is positioned on a first side of the patient's thumb and a detector is positioned to detect light energy emitted from the emitter.
  • the invention includes an oximetry system comprising an optical probe having an emitter substantially secured to a first side of a digit and a detector substantially secured to a second side of the digit, the first side and the second side being substantially perpendicular to a nail portion of the digit.
  • the oximetry system also includes an oximeter configured to interpret signals from the optical probe and a connector connecting the optical probe to the oximeter.
  • FIGURE 1 illustrates a simplified frontal view (in partial cross section) of a typical optical probe attached to a digit
  • FIGURE 2 illustrates a simplified frontal view (in partial cross section) of the optical probe of FIGURE 1 being physically depressed against an object;
  • FIGURE 3 illustrates a simplified frontal view (in partial cross section) of an optical probe according to aspects of an embodiment of the invention
  • FIGURE 4 illustrates a simplified frontal view (in partial cross section) of the optical probe of FIGURE 3 being physically depressed against an object
  • FIGURE 5 illustrates a simplified top plan view of an optical probe according to aspects of an embodiment of the invention
  • FIGURES 6A and 6B illustrate a simplified top view of the optical probe of FIGURE 5 attached to a thumb
  • FIGURE 7 illustrates a simplified top view of another optical probe attached to a digit, according to aspects of another embodiment of the invention.
  • Examination of a material is often advantageous, especially when difficult or expensive to procure and test a sample of the material. For example, in physiological measurements, it is often desirable to monitor a patient without drawing blood or tissue from the patient.
  • the known properties of energy absorption as energy propagates through a material may be used to determine information about the material through which the energy is passed. Energy is made incident on a material, and a measurement is made of energy either transmitted by, or reflected from, the material.
  • the amplitude of the measured signal is highly dependent on the thickness of the material through which the energy passes, or the optical path length, as well as other properties such as erratic movement of venous blood during motion.
  • l D is the energy transmitted from the emitter
  • S j is the absorption coefficient of the i th constituent, X
  • X is the thickness of the i th constituent through which light energy passes, or the optical path length of the i t constituent
  • is the concentration of the i th constituent in the thickness X,.
  • absorption is strongly dependent upon the thickness of the constituents that make up the medium through which the energy passes. For example, when the thickness of the medium changes due to motion, the thickness of the individual constituents change. This causes the absorption characteristics of the medium to change.
  • FIGURE 1 illustrates a simplified frontal view of a typical optical probe 100 attached to a digit 105.
  • the typical optical probe 100 includes an emitter 1 10 and a detector 1 15.
  • the digit 105 includes a nail portion 120, such as a fingernail.
  • the emitter 110 is typically positioned above the nail portion 120 of the digit 105.
  • the detector 115 is typically positioned substantially opposite the emitter 110, for example, underneath the digit 105.
  • an optical path length XI can be defined between the emitter 110 and the detector 115.
  • the optical path length X1 defines both the thickness of the tissue of the digit 105, and the volume of the tissue through which perfusion may be measured.
  • FIGURE 2 illustrates a simplified frontal view of the typical optical probe 100 being depressed against an object 200. As shown in FIGURE 2, the object 200 contacts the optical probe 100, for example at the detector 1 15, and depresses the tissue of the digit 105 toward the nail portion 120. Such physical depression can be caused by a wide number of patient movements, including, for example, a patient tapping the digit 105 against the object 200.
  • a new optical path length X2 is defined between the emitter 1 10 and the now depressed detector 115. Comparing FIGURE 2 to FIGURE 1, a change between the optical path lengths X1 and X2 can be recognized.
  • the change in optical path length of the prior art optical probe, or X P ⁇ is equal to X1-X2.
  • the change in optical path length X PA may be quite significant, and therefore, may significantly affect the ability of an oximeter to interpret the measured signal from the detector 1 15.
  • FIGURE 3 illustrates a simplified frontal view of an optical probe 300 according to aspects of an embodiment of the invention.
  • the optical probe 300 is attached to a digit 305.
  • the digit 305 comprises a patient's thumb.
  • the optical probe 300 further comprises an emitter 310 and a detector 315.
  • the digit 305 includes a nail portion 320, such as a thumbnail.
  • the optical probe 300 is preferably configured such that the emitter 310 and the detector 315 are on substantially opposing sides of the digit 305.
  • the emitter 310 and the detector 315 are preferably positioned at sides of the digit 305 substantially perpendicular to the side of the digit 305 having the nail portion 320.
  • the optical probe 300 advantageously positions the emitter 310 and the detector 315 in a manner rotated approximately ninety degrees from that of the conventional optical probe 100.
  • the optical probe 300 is disclosed with reference to a preferred embodiment, the invention is not intended to be limited thereby. Rather, a skilled artisan will recognize that the emitter 310 and the detector 315 may advantageously switch positions relative to the digit 305.
  • the preferred embodiment includes the emitter 310 positioned on the ulnar side of the digit 305
  • alternative embodiments may advantageously position the emitter 310 on the radial side of the digit 305.
  • the detector 315 is positioned to oppose the emitter 310 regardless of which side of the digit 305 the emitter 310 occupies.
  • the detector 315 is positioned to detect energy emitted from the emitter 310, such as, for example, to detect reflective or direct energy emissions.
  • the optical probe 300 includes adhesive material for attaching the emitter 310 and the detector 315 to the digit 305.
  • the attachment mechanism may advantageously comprise a spring-tension based reusable clip, a hook-and-loop material, other adhesive-type bandages, or the like.
  • the attachment mechanism may advantageously substantially secure the emitter 310 and the detector 315 to the digit 305 and block excessive ambient light from interfering with the transmitted energy sensed at the detector 315.
  • the optical probe 300 has an optical path length X3 defined as the length between the emitter 310 and the detector 315 when the optical probe 300 is attached to the digit 305. Similar to XI in FIGURE 1 and X2 in FIGURE 2, the optical path length X3 determines the volume of tissue through which perfusion is measured. As shown in FIGURE 3, the optical path length X3 is greater than the optical path lengths X1 and X2. Accordingly, the volume of tissue through which perfusion is measured is increased. By increasing the volume of tissue through which the perfusion is measured, the eventual signal produced by the detector 315 will advantageously include an increased signal-to-noise ratio. Moreover, because the preferred embodiment includes positioning of the optical probe over a thumb, the thumb advantageously increases the available perfusion.
  • FIGURE 4 illustrates the optical probe 300 being physically depressed against an object 400 according to aspects of an embodiment of the invention.
  • the digit 305 expands horizontally along an axis parallel to that of the nail portion 320 when depressed against the object 400.
  • Such depression may be caused by patient or caregiver agitation, such as for example, tapping of the digit against the object 400.
  • tapping As shown in FIGURE 4, as the digit 305 is compressed vertically, the tissue of the digit 305 expands horizontally.
  • the horizontal expansion is significantly less than the vertical depression for several reasons.
  • the tapping typically occurs on the underside of the digit 305, as opposed to one of the sides. Accordingly, such tapping depresses the malleable digit 305 as opposed to the rigid detector 315.
  • a new optical path length, X4 is defined as the distance between the emitter 310 and the detector 315 during the physical depression of the digit 305 against the object 400.
  • a new change in optical path length, X is equal to X4-X3.
  • the change in optical path length X is much smaller than the change in optical path length X PA , illustrated by the differences between X1 in FIGURE 1 and X2 in FIGURE 2. Therefore, by applying the optical probe 300 in a manner that positions the emitter 310 and the detector 315 on sides substantially opposite one another and substantially perpendicular to the side having the nail portion 320, the present invention advantageously reduces the change in optical path length during motion. This reduction in optical path length change advantageously reduces erratic absorption of optical energy by the tissue, thereby providing less erratic optical energy levels sensed by the detector 315, resulting in easier signals for the oximeter to interpret.
  • FIGURE 5 illustrates a top plan view of an optical probe 500 according to aspects of an embodiment of the invention.
  • the optical probe 500 includes a pair of adhesive flaps 502 and a pair of adhesive flanges 504 extending from a central portion 506.
  • the pair of adhesive flanges 504 preferably house an emitter 510 and a detector 515, both electrically connected to a flexible circuit 520.
  • the emitter 510 comprises at least one light-emitting diode, while the detector 515 comprises a photodetector. As shown in FIGURE 5, the emitter 510 and the detector 515 are preferably positioned near the centers of each adhesive flange 504, respectively.
  • the central portion 506 comprises an accordion-like stretchable material such that the distance between the adhesive flaps 502 and the adhesive flanges 504 may be advantageously increased or decreased to better fit differing sizes of digits.
  • the optical probe 500 also includes a connector portion 525.
  • the connector portion 525 preferably comprises accordion-like stretchable material similar to that of the central portion 506.
  • the connector portion 525 is preferably two to six inches in length.
  • the connector portion 525 preferably includes an exposed portion 530 of the flexible circuit 520, such that the connector portion 525 may advantageously connect to an oximeter or oximeter cable (not shown), as is known in the art.
  • the optical probe 500 is disclosed with reference to its preferred embodiment, the invention is not intended to be limited thereby. Rather, a skilled artisan will recognize from the disclosure herein a wide number of alternatives for the shape and structure of the optical probe 500.
  • the emitter 510 and the detector 515 may advantageously interchange their respective positions on the adhesive flanges 504.
  • the optical probe 500 attaches to a patient's thumb and the detector 515 is positioned on the radial side of the thumb such that the detector 515 does not contact the index finger.
  • the optical probe 500 may advantageously include left-hand and right-hand sensors such that the detector is always on the radial side.
  • a left-hand or right-hand thumb sensor may advantageously be attached to the thumb on the opposing hand by rotating the sensor 180 degrees around the opposing thumb, thereby avoiding contact between the detector 315 and the index finger.
  • the emitter 510 and the detector 515 may advantageously be positioned on the adhesive flaps 502 as opposed to the adhesive flanges 504.
  • the central portion 506 and the connector portion 525 may advantageously comprise nonstretchable material similar to that of the adhesive flaps 502 and the adhesive flange 504.
  • the optical probe 500 may advantageously comprise a reusable portion and a disposable portion.
  • the reusable portion may comprise the emitter 510, the detector 515, and the flexible circuit 520, while the disposable portion may comprise the adhesive flaps 502, the central portion 506, and the adhesive flanges 504.
  • the reusable portion may be withdrawn from the disposable portion, preferably sterilized, and then reused in a new disposable portion.
  • FIGURES 6A and 6B illustrate a simplified frontal and side view of the optical probe 500 of FIGURE 5 attached to the digit 305.
  • the digit 305 comprises the left-hand thumb. As shown in
  • the emitter 510 is advantageously positioned on the side of the digit 305 perpendicular to the side having the nail portion 320. As shown in FIGURE 6, the optical probe 500 folds at the central portion 506 around the end of the tip of the digit 305 such that the emitter 510 and the detector 515 are substantially secured to the digit 305.
  • the optical probe 500 is preferably fabricated from multiple layers, including a preferred flex circuit layer, a preferred MYLARTM layer, a preferred facestock tape layer, and other tape layers, as is known in the art.
  • FIGURE 7 illustrates a side view of an optical probe 700 attached to the digit 305, according to another embodiment of the invention.
  • the optical probe 700 preferably includes an optical probe as is conventionally known in the art.
  • the optical probe 700 may advantageously comprise an optical probe similar to that disclosed in the above-referenced U.S. Patent No. 5,782,757.
  • the optical probe 700 includes an emitter 710 and a detector 715 positioned on opposite sides of the digit 305 substantially perpendicular to the nail portion 320.
  • the conventional optical probe 700 may be applied to the digit 305 such that an optical path length between the emitter 710 and the detector 715 includes the advantages disclosed in the forgoing with reference to side-application of the optical probes 300 and 500, respectively.
  • the optical probes 300, 500, and 700 may be advantageously applied to a finger or toe.
  • the optical probes 300, 500, and 700 may advantageously be housed in a spring-tension-based clip, a hook-and-loop bandage, such as Velcro, disposable, reusable, or differing shaped adhesive attachment mechanisms.

Landscapes

  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Physics & Mathematics (AREA)
  • Biomedical Technology (AREA)
  • Medical Informatics (AREA)
  • Biophysics (AREA)
  • Pathology (AREA)
  • Engineering & Computer Science (AREA)
  • Veterinary Medicine (AREA)
  • Heart & Thoracic Surgery (AREA)
  • Public Health (AREA)
  • Molecular Biology (AREA)
  • Surgery (AREA)
  • Animal Behavior & Ethology (AREA)
  • General Health & Medical Sciences (AREA)
  • Optics & Photonics (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Measurement Of The Respiration, Hearing Ability, Form, And Blood Characteristics Of Living Organisms (AREA)

Abstract

La présente invention concerne une sonde optique appliquée sur un doigt, tel qu'un pouce, de sorte que cette sonde optique inclut un émetteur et un détecteur sur les côtés opposés de ce doigt, perpendiculairement au côté ongle de ce doigt, et de manière que la lumière traverse de doigt dans un plan parallèle à l'ongle. L'application latérale de cette sonde optique permet d'obtenir une modification réduite de la longueur de trajet optique pendant un déplacement et un plus gros volume à travers lequel on peut mesurer la perfusion, ce qui entraîne une production de signal par le détecteur dont le rapport signal/bruit est augmenté.
PCT/US2001/041718 2000-08-18 2001-08-14 Hematometre pour doigt a application laterale WO2002015782A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US64154300A 2000-08-18 2000-08-18
US09/641,543 2000-08-18

Publications (1)

Publication Number Publication Date
WO2002015782A1 true WO2002015782A1 (fr) 2002-02-28

Family

ID=24572834

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2001/041718 WO2002015782A1 (fr) 2000-08-18 2001-08-14 Hematometre pour doigt a application laterale

Country Status (1)

Country Link
WO (1) WO2002015782A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112190244A (zh) * 2020-09-22 2021-01-08 深圳市昊锐新电子有限公司 一种手指血压仪

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5370114A (en) * 1992-03-12 1994-12-06 Wong; Jacob Y. Non-invasive blood chemistry measurement by stimulated infrared relaxation emission
US5522388A (en) * 1993-09-22 1996-06-04 Kowa Company Ltd. Pulse spectrometer
US5551422A (en) * 1992-11-09 1996-09-03 Boehringer Mannheim Gmbh Method and apparatus for analytical determination of glucose in a biological matrix
US5782757A (en) 1991-03-21 1998-07-21 Masimo Corporation Low-noise optical probes
US5846190A (en) * 1995-10-10 1998-12-08 Hewlett-Packard Company Method of and apparatus for recognizing falsified pulse oximetry measurements

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5782757A (en) 1991-03-21 1998-07-21 Masimo Corporation Low-noise optical probes
US5370114A (en) * 1992-03-12 1994-12-06 Wong; Jacob Y. Non-invasive blood chemistry measurement by stimulated infrared relaxation emission
US5551422A (en) * 1992-11-09 1996-09-03 Boehringer Mannheim Gmbh Method and apparatus for analytical determination of glucose in a biological matrix
US5522388A (en) * 1993-09-22 1996-06-04 Kowa Company Ltd. Pulse spectrometer
US5846190A (en) * 1995-10-10 1998-12-08 Hewlett-Packard Company Method of and apparatus for recognizing falsified pulse oximetry measurements

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112190244A (zh) * 2020-09-22 2021-01-08 深圳市昊锐新电子有限公司 一种手指血压仪

Similar Documents

Publication Publication Date Title
US10478107B2 (en) Non-invasive physiological sensor cover
US5452717A (en) Finger-cot probe
US6813511B2 (en) Low-noise optical probes for reducing ambient noise
JP3940437B2 (ja) 幼児／新生児用のパルス酸素計センサー
US10952675B2 (en) Apparatus and methods for non-invasively measuring a patient's arterial blood pressure
Fernandez et al. Evaluation of a new pulse oximeter sensor
CN1358075A (zh) 脉冲血氧计探头移离检测系统
WO1999047039A1 (fr) Oxymetre infrarouge s'adaptant a son emplacement de positionnement
EP2112902B1 (fr) Element destine a mesurer la pression sanguine systolique dans la cheville à l'aide de ppg
WO2002015782A1 (fr) Hematometre pour doigt a application laterale
EP1599711B1 (fr) Detecteur de pression miniaturise dynamique et ultrasensible a isolation electrique et a couplage optique
US20100099962A1 (en) Sensing device and positioning structure thereof
CN221205446U (zh) 心电传感器及心电诊断设备
Podlepetskii et al. Microelectronic transducers and converters for noninvasive monitoring of the functional systems of humans

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): JP

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE TR

121 Ep: the epo has been informed by wipo that ep was designated in this application
DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
122 Ep: pct application non-entry in european phase
NENP Non-entry into the national phase

Ref country code: JP