JPH05115466A - Metabolic information measuring instrument - Google Patents

Abstract

PURPOSE:To provide the subject instrument which can exactly measure the metabolic information at the plural points of a biotissue in a short period of time. CONSTITUTION:A probe 6 provided freely movably along an axial direction is provided in a catheter 4 which is provided with a light transparent part 5a and a light shielding part 5b along the axial direction and has flexibility. An irradiating surface 7a which is provided along the axial direction and emits inspecting light and a photodetecting surface 8a which receives the inspecting light are provided in this probe 6. The inspecting light projected from the irradiating surface 7a transmits the biotissue while scattering and reflecting. The reflected light is received by the photodetecting surface 8a but the reflected light which does not contain the metabolic information is shielded by the light shielding part 5b and is prevented from being received from the photodetecting surface 8a.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for measuring metabolic information of biological tissue, which is suitable for measuring biological information such as oxygen saturation in biological tissue and organs such as heart and brain using light, that is, oxygen metabolism. Regarding

[0002]

2. Description of the Related Art Light in the red to near-infrared region has high permeability to living tissues and its light absorption and oxygen binding information to substances that control oxygen metabolism of living organisms such as hemoglobin, myoglobin, and cytochrome oxidase. It has features such as corresponding changes in absorption spectrum.

Utilizing such characteristics, USP422
As shown in 3680, US Pat. No. 4,281,645, a method of measuring oxygen metabolism of various organs such as heart and brain in a living body is known. This is 700-1300n
Light in the near-infrared region of m is applied to an organ or a tissue in a living body, reflected light reflected from the deep organ or tissue or light transmitted therethrough is detected, and light intensity between wavelengths is compared and calculated. It measures blood volume, hemoglobin and cytochrome oxygenation.

Here, the cytochrome is a pigment protein (oxidized Cu2 + reduced Cu +) having copper existing in the mitochondria of cells. Usually, 80% is an oxidative type, but during ischemia, it becomes a reducing type early. Therefore, the redox state of cytochrome can be measured from the absorption amount at each wavelength, and it can be used as an index of tissue oxygen metabolism.

When myocardial infarction occurs, myocardial necrosis is caused in the worst case, but in early or acute cases, myocardial activity is stopped but sometimes it is not. In such a case, PTCA and bypass are effective. So far
I used PET to diagnose whether myocardium was alive or dead, and decided to perform bypass surgery.
ET devices are extremely expensive and not very popular.

When measuring the myocardial tissue, in practice, the scope is inserted from the aorta of the lower extremity, and as shown in FIG. Diagnosis is performed by occluding a balloon for a predetermined period of time and measuring metabolic changes in myocardium. At this time, since there is no metabolic change when the myocardium is dead, it is possible to diagnose whether the myocardium is alive or dead.

By the way, Japanese Patent Application Laid-Open No. 59-230533, which is known as a conventional metabolic information measuring apparatus, projects light from a light source onto a living tissue through a light projecting fiber,
The reflected light from the living tissue is transmitted to the light receiving part using a plurality of optical fiber bundles, and after being separated by different wavelength filters provided on the end faces, the intensity of the reflected light is measured for each wavelength and the target living body It measures the information of the organization.

Further, Japanese Patent Publication No. 61-11614 discloses
Near-infrared regions including light of various wavelengths within a spectrum range of 700 to 1300 nm are alternately and intermittently projected onto a living tissue in a predetermined cycle, and reflected light from the living tissue is received by a light receiving unit, Information on the target biological tissue is measured by measuring the intensity of reflected light for each wavelength.

[0009]

By the way, USP42
In both patents of 23680 and USP 4281645,
The applicant emphasizes that when measuring oxygen metabolism using light in the near infrared region, the light path must be relatively long. In other words, the fact that it spans a long path can include the metabolic information of the deep part in the target tissue.

Further, in the case of irradiating and detecting the metabolism of an organ with light from one direction (this is called a reflection system), in order to achieve the above-mentioned object, the light irradiation part and the detection part are separated from each other by several centimeters. States that it is necessary. “Monitoring cerebral oxygen metabolism during external circulation using near-infrared biometrics” In artificial organ 19 (1) 535-538 (1990), the irradiation part and the detection part are 3 to measure oxygen metabolism in the brain. 4 cm apart.

In recent years, an endoscope which uses an optical fiber bundle to observe not only the stomach and large intestine but also the inside of blood vessels has been used in general medicine. This endoscope has a characteristic that a disease can be diagnosed accurately and early by directly observing an organ that cannot be seen from the outside from the body cavity.

Furthermore, the endoscope is provided with a hole called a channel, and a treatment instrument such as biopsy forceps or an electric scalpel can be inserted into the body through the channel from the outside. Used for medical treatment.

Recently, an optical fiber probe for measuring oxygen saturation using this channel is inserted to diagnose metabolic information of a lesion site, or an optical probe is directly inserted under X-ray fluoroscopy to detect organs. Studies are being conducted to determine the oxygen metabolism of.

Regarding the optical probe, "Medical reflection spectrum analyzer using optical fiber probe" Medical Electronics and Biotechnology Vol.28 No3 (1990), JP-A-59-2305
Detailed in 33.

By the way, the above-mentioned optical fiber probe has a small outer diameter at the insertion portion of the probe so that it can be inserted into the body cavity, and therefore the irradiation portion for irradiating light and the detecting portion for detecting are extremely close to each other. Since it is arranged and uses pulsed light with a time width that is sufficiently longer than the speed of light,
It is designed to detect light that has passed through the tissue surface without crossing a relatively long path. That is, such a method measures the metabolic information only on the surface of the tissue, and the metabolic information in the deep tissue cannot be measured because it is strongly influenced by the epidermis of the tissue, the body fluid attached to the surface of the epidermis, and blood.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a metabolic information measuring device capable of accurately measuring metabolic information of a plurality of parts of a living tissue.

[0017]

In order to achieve the above-mentioned object, the present invention provides a metabolic information measuring apparatus for measuring metabolic information of a tissue by detecting inspection light passing through a living tissue, which is flexible. A guide member having, and a probe movably provided in the guide member along the axial direction,
This probe is provided with an inspection light emitting portion provided along the axial direction and an inspection light receiving portion for receiving the inspection light.

[0018]

When the guide member inserted into the body cavity of the living body is pressed against the living tissue and the probe having the inspection light emitting portion and the inspection light receiving portion is inserted into the guide member, the probe is guided to the target site by the guide member. When the inspection light is emitted from the inspection light emitting portion of the probe, the inspection light is transmitted while being scattered and reflected by the living tissue, and is received by the inspection light receiving portion to measure metabolic information.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

Reference numeral 4 shown in FIG. 1 denotes a catheter as a guide member, which is formed by a long hollow pipe having a semicircular cross section and flexibility, and a flat surface 4 parallel to the axial direction.
It has a and an arc surface 4b. Therefore, when the catheter 4 is bent, the center of curvature of the catheter 4 is arranged in a direction perpendicular to this plane, and the catheter 4 is formed in a shape in which movement in the circumferential direction is restricted.

Further, on the outer peripheral surface of the catheter 4, a plurality of light transmitting portions 5a and a plurality of light shielding portions 5b are alternately provided at predetermined intervals along the axial direction. The light transmitting portion 5a is formed on a light transmitting surface which transmits inspection light, which will be described later, and the light shielding portion 5a.
b is formed of a light shielding film or a light absorbing film that shields the inspection light.

A metabolic information detecting probe 6 is slidably inserted into the catheter 4 in the axial direction, and at least the tip of the probe 6 follows the inner shape of the catheter 4. Flat surface 6 parallel to the direction
It has a and an arc surface 6b.

The probe 6 is internally provided with an irradiation fiber 7 for guiding the irradiation light as the inspection light and a light receiving fiber 8 for guiding the received inspection light along its axial direction. The irradiating fiber 7 is connected to the irradiating surface 7a as an inspection light emitting portion provided on the flat surface 6a of the probe 6, and the light receiving fiber 8 is connected to the flat surface 6a of the probe 6.
It is connected to the light receiving surface 8a as the inspection light receiving portion provided in the. The irradiation surface 7a and the light receiving surface 8a are separated from each other along the axial direction of the probe 5, and the distance between the irradiation surface 7a and the light receiving surface 8a is equal to the distance between the light shielding portions 5b of the catheter 4.

On the other hand, the other end of the irradiation fiber 7 of the probe 6 faces a laser diode 9 as a light source for emitting pulsed light, and the light reception fiber 8 faces a light receiving element 10 as a detector. Therefore, when the laser diode 9 emits pulsed light of a predetermined wavelength, it is irradiated from the irradiation surface 7a through the irradiation fiber 7, and the reflected light received from the light receiving surface 8a is guided by the light receiving fiber 8. The light receiving element 10 receives light.

The pulsed light is, for example, near-infrared light having a wavelength of 700 nm to 950 nm which has absorption in cytochrome and hemoglobin containing oxygen metabolism information, and can effectively capture the reflected light that has passed through the deep part of the living tissue. This reflected light can be detected by the light receiving element 10 and the detection light of each wavelength is calculated to obtain the oxygen saturation levels of hemoglobin, myoglobin, and cytochrome.

Next, the operation of the metabolic information measuring device configured as described above will be described. First, FIG. 3 and FIG.
As shown in, the catheter 4 is inserted into the living body cavity, and the flat surface 4a of the distal end portion of the catheter 4 is pressed against the myocardium 3 as a living tissue.

Next, the probe 6 is inserted into the catheter 4, and the probe 6 is guided to the tip of the catheter 4 by using the catheter 4 as a guide. When the probe 6 is irradiated with pulsed light from the irradiation surface 7a in a state where the irradiation surface 7a and the light receiving surface 8a are positioned on the light transmitting portion 4a as shown in FIG. 2 (a), the irradiation light emitted is myocardium. The reflected light that has propagated through the living tissue 3 and has passed through the living tissue is received by the light receiving surface 8a.

However, the irradiation light emitted from the irradiation surface 7a is reflected between the probe 6 and the catheter 4, inside the catheter 4 and between the catheter 4 and the myocardium 3, and the reflected light is received by the light receiving surface 8a. Will end up. That is, the reflected light that does not include metabolic information is received from the light receiving surface 8a, so that the metabolic information cannot be accurately measured. However, as shown in FIG. 2B, the probe 6 is slid in the axial direction with respect to the catheter 4, and the light shielding portion 5b of the catheter 4 is positioned between the irradiation surface 7a and the light receiving surface 8a. 7a and light receiving surface 8
a is located in the light transmitting portions 5a and 5a, respectively.

When pulsed light is irradiated from the irradiation surface 7a in the same manner as described above, the irradiated irradiation light travels while diffusing in the living tissue of the myocardium 3, and the reflected light passing through the living tissue is received by the light receiving surface 8a. Received light.

At this time, even if the irradiation light emitted from the irradiation surface 7a is guided between the probe 6 and the catheter 4 and inside the catheter 4 and between the catheter 4 and the myocardium 3, the reflected light is the light shielding portion. Is blocked or absorbed by 5b, that is,
The reflected light that does not include metabolic information is removed, and only the reflected light that includes metabolic information is received from the light receiving surface 8a, and the metabolic information can be accurately measured.

After measuring one measurement site of the myocardium 3 as described above, the probe 6 is slid in the axial direction with respect to the catheter 4 so that the irradiation surface 7a and the light receiving surface 8a of the probe 6 are measured on another measurement surface. By irradiating irradiation light from the irradiation surface 7a again at the site, it is possible to measure a plurality of points of the myocardium 3, and by inserting the catheter 4 into the body cavity and placing
A wide range of metabolic states can be measured.

[0032]

As described above, according to the present invention, the guide member inserted in the body cavity of the living body is pressed against the living tissue, and the guide member has the inspection light emitting portion and the inspection light receiving portion as a guide. When the probe is inserted and the inspection light is emitted from the inspection light emitting portion of the probe, the inspection light is transmitted while being scattered and reflected by the living tissue, and is received by the inspection light receiving portion.

Therefore, the probe can be easily guided to the target site, and by inserting and placing the guide member in the body cavity, the guide member can be guided and the probe can be inserted many times. Further, there is an effect that it is possible to easily measure a plurality of measurement sites of the living tissue in a short time.

[Brief description of drawings]

FIG. 1 is a perspective view of a distal end portion of a catheter and a probe of a metabolic information measuring device according to an embodiment of the present invention.

2 (a) and 2 (b) are vertical cross-sectional side views of the same embodiment in use.

FIG. 3 is a perspective view showing a state where the catheter and the probe of the embodiment are inserted into a body cavity.

FIG. 4 is a perspective view showing a state in which the catheter and the probe of the same embodiment are brought into close contact with myocardium.

FIG. 5 is a perspective view showing a general measurement state of a myocardium.

[Explanation of symbols]

4 ... Catheter, 6 ... Probe, 7 ... Irradiation fiber, 8 ... Receiving fiber, 7a ... Irradiation surface, 8a ... Receiving surface.

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[Procedure amendment]

[Submission date] February 21, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0010

[Correction method] Change

[Correction content]

Further, in the case of irradiating and detecting the metabolism of an organ with light from one direction (this is called a reflection system), in order to achieve the above-mentioned object, the light irradiation part and the detection part are separated from each other by several centimeters. States that it is necessary. “Monitoring cerebral oxygen metabolism during extracorporeal circulation using near-infrared biometrics” In artificial organ 19 (1) 535-538 (1990), the irradiation unit and the detection unit are 3 to 3 in order to measure oxygen metabolism in the brain. 4 cm
Separated.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0011

[Correction method] Change

[Correction content]

In recent years, an endoscope which uses an optical fiber bundle to observe not only the stomach and large intestine but also the inside of blood vessels has been used in general medicine. This endoscope is the body
By directly observing internal organs that cannot be seen from the inside of the body cavity, it is possible to accurately and early diagnose diseases.

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0012

[Correction method] Change

[Correction content]

Further, the endoscope is provided with a hole called a channel, and a treatment tool such as a biopsy forceps or an electric scalpel can be inserted into the body from the outside of the body through the channel to diagnose a lesion portion which cannot be detected by image diagnosis. Used for medical treatment.

[Procedure amendment 4]

[Document name to be amended] Statement

[Name of item to be corrected] 0023

[Correction method] Change

[Correction content]

The probe 6 is internally provided with an irradiation fiber 7 for guiding the irradiation light as the inspection light and a light receiving fiber 8 for guiding the received inspection light along its axial direction. The irradiating fiber 7 is connected to the irradiating surface 7a as an inspection light emitting portion provided on the flat surface 6a of the probe 6, and the light receiving fiber 8 is connected to the flat surface 6a of the probe 6.
It is connected to the light receiving surface 8a as the inspection light receiving portion provided in the. The irradiation surface 7a and the light receiving surface 8a are separated from each other along the axial direction of the probe 6 , and this distance is equal to the distance between the light shielding portions 5b of the catheter 4.

Front Page Continuation (72) Inventor Yasuhiko Omagari 2-43-2 Hatagaya, Shibuya-ku, Tokyo Within Olympus Optical Co., Ltd. (72) Inventor Yoshio Tashiro 2-43-2 Hatagaya, Shibuya-ku, Tokyo Olympus Optics Kogyo Co., Ltd. (72) Inventor Issei Nakamura 2-43-2 Hatagaya, Shibuya-ku, Tokyo Olympus Optical Co., Ltd. (72) Koichi Umeyama 2-43-2 Hatagaya, Shibuya-ku, Tokyo Olympus Optical Industry Co., Ltd. (72) Inventor Yoshinao Daimei 2-43-2 Hatagaya, Shibuya-ku, Tokyo Olympus Optical Industry Co., Ltd. (72) Inventor Seiji Yamaguchi 2-43-2 Hatagaya, Shibuya-ku, Tokyo Olympus Inside Optical Industry Co., Ltd. (72) Inventor Shuichi Takayama 2-43-2 Hatagaya, Shibuya-ku, Tokyo Inside Olympus Optical Industry Co., Ltd.

Claims (1)

[Claims] 1. A metabolic information measuring device for measuring metabolic information of a tissue by detecting an inspection light transmitted through a living tissue, wherein a flexible guide member and an axial direction within the guide member are provided. A metabolic information measuring device comprising: a probe that is movably provided; and a test light emitting unit and an test light receiving unit that receives the test light and that is provided along the axial direction of the probe.