JPH08182658A - Blood flow measuring method and blood flow measuring device - Google Patents
Blood flow measuring method and blood flow measuring deviceInfo
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- JPH08182658A JPH08182658A JP6339594A JP33959494A JPH08182658A JP H08182658 A JPH08182658 A JP H08182658A JP 6339594 A JP6339594 A JP 6339594A JP 33959494 A JP33959494 A JP 33959494A JP H08182658 A JPH08182658 A JP H08182658A
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- blood flow
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- laser
- flow measuring
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Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、皮膚の血流状態をレー
ザードップラー方式によって測定する血流測定方法及び
その測定に使用する血流測定装置に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a blood flow measuring method for measuring a blood flow state of skin by a laser Doppler method and a blood flow measuring device used for the measurement.
【０００２】[0002]
【従来の技術】皮膚の血流に関するデータは、皮膚組織
の代謝活性の状態、新陳代謝の状態、老化度、その他種
々の皮膚の性状に依存するため、皮膚の血流の測定は、
皮膚の健康状態を判断する上で重要である。そのため、
皮膚科の医師、化粧品関係のアドバイザー、医薬品又は
化粧品関係者等により血液の流速あるいは流量といった
血流に関するデータが測定されている。2. Description of the Related Art Since the data on the blood flow in the skin depend on the metabolic activity state of the skin tissue, the metabolic state, the aging degree and various other skin properties, the measurement of the blood flow in the skin is
It is important in determining the health of the skin. for that reason,
Data relating to blood flow such as the flow velocity or flow rate of blood is measured by a dermatologist, an advisor related to cosmetics, a person related to pharmaceuticals or cosmetics, and the like.
【０００３】血流測定方法としては、皮膚に侵襲を与え
ず、血流量の瞬間値を連続的に測定できることから、レ
ーザードップラー方式による測定方法が広く行われてい
る。As a blood flow measuring method, a laser Doppler method is widely used because it can continuously measure the instantaneous value of blood flow without invading the skin.
【０００４】レーザードップラー方式による血流測定方
法は、レーザー光の単色性、可干渉性を利用し、レーザ
ー光が皮膚内の血球により散乱された場合に生じる、血
球の速度及び個数に応じた周波数及び振幅を、ヘテロダ
イン検波によって検出し血流信号に変換処理する方法で
ある。The blood flow measurement method using the laser Doppler method utilizes the monochromaticity and coherence of laser light, and a frequency corresponding to the speed and number of blood cells produced when the laser light is scattered by blood cells in the skin. And amplitude are detected by heterodyne detection and converted into a blood flow signal.
【０００５】このレーザードップラー方式の血流測定を
行う場合に使用するセンサとしては、図７に示したセン
サ１ａのように、光源から皮膚表面にレーザー光を入射
させる送光用光ファイバー２と、皮膚からの散乱光を受
光する受光用光ファイバー３とが一対になったセンサ素
子４を、皮膚に対する接触面が円形又は楕円形のプロー
ブ支持部材５に埋め込んだものが主に知られている。As the sensor used for measuring the blood flow of the laser Doppler system, as in the case of the sensor 1a shown in FIG. 7, a light-transmitting optical fiber 2 for injecting laser light from the light source to the skin surface, and the skin It is known that a sensor element 4 in which a light receiving optical fiber 3 for receiving scattered light from a pair is embedded in a probe supporting member 5 having a circular or elliptical contact surface with respect to skin.
【０００６】しかし、図７に示したように単一のセンサ
素子４からなるセンサ１ａでは、直径１ｍｍ程度の狭い
部分の情報しか得られず、わずかな測定部位の位置ずれ
によっても測定値がばらつき、データの再現性に乏しい
という問題がある。そこで、図８に示したセンサ１ｂの
ように、光ファイバーを分岐させて一つのセンサ内に複
数のセンサ素子４ａ〜４ｇを設けることが提案されてい
る。この複数のセンサ素子４ａ〜４ｇで検出された測定
値は平均化されるので、個々のセンサ素子におけるばら
つきが相殺されて再現性の高い測定結果を得ることが可
能となる。However, as shown in FIG. 7, the sensor 1a consisting of a single sensor element 4 can obtain only information on a narrow portion having a diameter of about 1 mm, and the measured values vary even if the position of the measuring portion is slightly displaced. However, there is a problem that the reproducibility of data is poor. Therefore, as in the sensor 1b shown in FIG. 8, it has been proposed to branch an optical fiber to provide a plurality of sensor elements 4a to 4g in one sensor. Since the measurement values detected by the plurality of sensor elements 4a to 4g are averaged, the variations in the individual sensor elements are offset and a highly reproducible measurement result can be obtained.
【０００７】また、このようなセンサ１ａ、１ｂを用い
て血流測定を行う場合に、個々の測定時の測定深度を調
整するため、皮膚に照射するレーザー光の出力を可変に
したり、センサ素子の皮膚接触面における送光用光ファ
イバー２と受光用光ファイバー３との間隔を調整するこ
とも提案されている（特開平５−１１１４６９号公
報）。Further, when blood flow measurement is performed using such sensors 1a and 1b, the output of laser light irradiating the skin is made variable or the sensor element is adjusted in order to adjust the measurement depth at each measurement. It has also been proposed to adjust the distance between the light-transmitting optical fiber 2 and the light-receiving optical fiber 3 on the skin contact surface (JP-A-5-111469).
【０００８】[0008]
【発明が解決しようとする課題】しかしながら、図８に
示したように光ファイバーを分岐させて複数のセンサ素
子４ａ〜４ｇを設けると、個々のセンサ素子におけるレ
ーザーパワーが低くなるので、皮膚表面の比較的浅い部
分の血流量しか測定できない。However, when a plurality of sensor elements 4a to 4g are provided by branching an optical fiber as shown in FIG. 8, the laser power in each sensor element becomes low. Only the blood flow in the shallow part can be measured.
【０００９】またこの場合、レーザー光の出力や、セン
サ素子の皮膚接触面における送光用光ファイバー２と受
光用光ファイバー３との間隔、即ち送光部と受光部の間
隔を変えることにより、測定深度を個別的に調整するこ
とはしていても、種々の測定深度の血流量を同時に測定
することはしていない。そのため、深さ方向の血流量分
布を知ることができず、皮膚組織の状態分析を正確に行
うことができないという問題がある。Further, in this case, the measurement depth can be changed by changing the output of the laser beam or the distance between the light transmitting optical fiber 2 and the light receiving optical fiber 3 on the skin contact surface of the sensor element, that is, the distance between the light transmitting portion and the light receiving portion. However, the blood flow rate at various measurement depths is not measured at the same time. Therefore, there is a problem in that the blood flow distribution in the depth direction cannot be known and the skin tissue state cannot be accurately analyzed.
【００１０】例えば、マッサージあるいは血行促進剤の
投与の前後に、従来のレーザードップラー方式による血
流測定とサーモグラフィーによる皮膚表面温度測定との
双方をそれぞれ行った場合に、血流測定による血流量は
上昇しているが、サーモグラフィーによる皮膚温度は降
下していたり、あるいは、血流測定による血流量は下降
しているが、サーモグラフィーによる皮膚温度は上昇し
ているという、一見矛盾したように見える結果が生じる
場合がある。このような結果は、血流測定の測定部位と
サーモグラフィーによる測定部位とが、一致していない
ことによるものである。即ち、一般に皮膚には、表皮面
に平行して、表皮面から毛細血管、細小血管（乳頭下層
血管叢）、細血管（細動脈網、細静脈網）、小血管（小
動脈網、小静脈網）の４層の微細血管網が存在してお
り、これらは、それぞれ異なる機能を有し、マッサージ
や血行促進剤の影響の現れ方も異なっている。そして、
血流測定では比較的浅い部位に位置する細小血管の血流
量を測定しており、サーモグラフィーでは細動脈周辺の
深い血管からの熱の伝播を主体とする皮膚表面温度を測
定している。このため、上述のような測定結果が得られ
ることとなる。For example, when both the blood flow measurement by the conventional laser Doppler method and the skin surface temperature measurement by thermography are performed before and after the massage or the administration of the blood circulation promoting agent, the blood flow rate increases by the blood flow measurement. However, the skin temperature measured by thermography is decreasing, or the blood flow measured by blood flow measurement is decreasing, but the skin temperature measured by thermography is increasing. There are cases. Such a result is because the measurement site of blood flow measurement and the measurement site of thermography do not match. That is, in general, the skin is parallel to the epidermis surface from the epidermis surface to capillaries, small blood vessels (subpapillary plexus), small blood vessels (arteriole network, venous network), small blood vessels (small arterial network, venule). There are four layers of microvessel network (net), each of which has a different function, and the effects of massage and blood circulation promoters are also different. And
Blood flow measurement measures the blood flow rate of small blood vessels located in a relatively shallow region, and thermography measures the skin surface temperature, which is mainly due to heat transfer from deep blood vessels around arterioles. Therefore, the measurement result as described above can be obtained.
【００１１】したがって、血流測定においては、皮膚表
層の浅い部位から深い部位に至るまでの深度範囲の微細
血管網の血流状態を異なる深度ごとに同時に把握し、正
確なデータ解析ができるようにすることが望まれてい
た。Therefore, in blood flow measurement, the blood flow state of the microvascular network in the depth range from the shallow portion to the deep portion of the skin surface layer can be simultaneously grasped for different depths so that accurate data analysis can be performed. It was desired to do.
【００１２】本発明は以上のような従来技術の課題を解
決しようとするものであり、データの再現性を確保しつ
つ、皮膚表層の浅い部位から深い部位に至る深度範囲の
血流量をそれぞれの深度ごとに同時に記録できるように
することを目的としている。The present invention is intended to solve the problems of the prior art as described above, and while ensuring the reproducibility of the data, the blood flow rate in the depth range from the shallow portion to the deep portion of the skin surface layer is controlled. The purpose is to enable simultaneous recording for each depth.
【００１３】[0013]
【課題を解決するための手段】本発明者らは、被検体に
レーザー光を入射させ、被検体内で散乱した光を受光し
て被検体の血流量を測定するレーザードップラー方式の
血流測定方法において、被検体にレーザを入射させる送
光部と、被検体からの散乱光を受光する受光部との距離
から測定深度を具体的に推定できること、さらに、送光
部から異なる距離にある複数の受光部で同時に受光し、
その送光部からの異なる距離ごとの血流量をそれぞれ求
め、同時に記録することにより、異なる測定深度ごとの
血流量を同時に記録できるので、上述の目的が達成でき
ることを見出し、本発明を完成させるに至った。DISCLOSURE OF THE INVENTION The present inventors have made a laser Doppler blood flow measurement in which a laser beam is made incident on a subject and the light scattered in the subject is received to measure the blood flow in the subject. In the method, the measurement depth can be specifically estimated from the distance between the light-transmitting unit that makes the laser enter the subject and the light-receiving unit that receives the scattered light from the subject. Furthermore, a plurality of measurement depths different from the light-transmitting unit can be obtained. The light receiving section of the
Obtaining the blood flow rate for each different distance from the light transmitting unit, by recording simultaneously, it is possible to simultaneously record the blood flow rate for each different measurement depth, to find that the above-mentioned object can be achieved, and to complete the present invention. I arrived.
【００１４】即ち、本発明は、被検体にレーザー光を入
射させ、被検体内で散乱した光を受光して被検体の血流
量を測定するレーザードップラー方式の血流測定方法に
おいて、被検体にレーザ光を入射させる少なくとも一つ
の送光部に対し、該送光部からの距離が異なる複数の位
置を受光部とし、各受光部で被検体からの散乱光を受光
してそれぞれの受光部における血流量を測定し、それに
より測定深度の異なる血流量を同時に記録することを特
徴とする血流測定方法を提供する。That is, the present invention provides a laser Doppler blood flow measuring method in which a laser beam is incident on a subject and the light scattered in the subject is received to measure the blood flow in the subject. With respect to at least one light-transmitting unit that makes laser light incident, a plurality of positions having different distances from the light-transmitting unit are used as light-receiving units, and each light-receiving unit receives scattered light from the subject and receives light at each light-receiving unit. Provided is a blood flow measuring method characterized in that blood flow is measured, and thereby blood flows having different measurement depths are simultaneously recorded.
【００１５】また、この方法の好ましい態様として、送
光部からの異なる距離にある受光部を、送光部からの距
離ごとに複数設け、それら複数の受光部における受光光
を合わせて当該距離における血流量を測定する方法を提
供する。さらに、被検体に入射させるレーザーパワーを
変化させ、異なるパワーの入射レーザー光ごとに血流量
を測定し、それによっても測定深度の異なる血流量を同
時に記録する方法を提供する。Further, as a preferred mode of this method, a plurality of light-receiving units located at different distances from the light-transmitting unit are provided for each distance from the light-transmitting unit, and the light-receiving units collectively receive light at the distance. A method of measuring blood flow is provided. Furthermore, a method is provided in which the laser power incident on the subject is changed, the blood flow rate is measured for each of the incident laser beams having different powers, and the blood flow rate at different measurement depths is simultaneously recorded.
【００１６】また、このような方法を実施する装置とし
て、レーザー光を発する光源部、光源部で発せられたレ
ーザー光を被検体に入射させ、被検体からの散乱光を受
光するセンサ部、センサ部からの信号を血流信号に変換
する信号処理手段、信号処理手段からの信号に基づいて
測定結果を表示する表示手段を有する血流測定装置にお
いて、センサ部が、被検体にレーザー光を入射させる少
なくとも一つの送光部と、被検体からの散乱光を受光す
る複数の受光部とを有し、かつそれら複数の受光部は送
光部から互いに異なる距離に設けられていることを特徴
とする血流測定装置を提供する。As an apparatus for carrying out such a method, a light source section for emitting a laser beam, a sensor section for making a laser beam emitted by the light source section incident on a subject, and receiving scattered light from the subject, a sensor In a blood flow measuring device having a signal processing means for converting a signal from a blood flow signal into a blood flow signal, and a display means for displaying a measurement result based on the signal from the signal processing means, a sensor part causes a laser beam to enter a subject. At least one light-transmitting part to be made to have, and a plurality of light-receiving parts for receiving scattered light from the subject, and the plurality of light-receiving parts are provided at different distances from the light-transmitting part. Provided is a blood flow measuring device.
【００１７】また、この装置の好ましい態様として、セ
ンサ部の前段に、被検体に入射させるレーザー光のパワ
ーを調整するレーザーパワー調整手段が設けられた装置
を提供する。また、センサ部が、送光部から異なる距離
ごとの受光部として、複数の受光部を有し、これらの複
数の受光部での受光光を合わせ、送光部から当該距離に
ある受光部の血流量が得られるようにした装置を提供す
る。As a preferred embodiment of this apparatus, there is provided an apparatus in which a laser power adjusting means for adjusting the power of the laser beam incident on the subject is provided in the preceding stage of the sensor section. In addition, the sensor unit has a plurality of light receiving units as light receiving units for different distances from the light transmitting unit, and the light received by the plurality of light receiving units is combined to obtain a light receiving unit at the distance from the light transmitting unit. Provided is a device capable of obtaining a blood flow rate.
【００１８】[0018]
【作用】本発明によれば、送光部から被検体にレーザー
光を入射させ、被検体からの散乱光を受光部で受光して
レーザードップラー方式により血流測定を行うに際し、
送光部からの距離が異なる複数の位置を受光部とするの
で、異なる測定深度の血流量を同時に測定し、測定深度
ごとの血流量を同時に記録することが可能となる。According to the present invention, when the laser beam is incident on the subject from the light transmitting unit and the scattered light from the subject is received by the light receiving unit and blood flow is measured by the laser Doppler method,
Since a plurality of positions having different distances from the light transmitting unit are used as the light receiving unit, it is possible to simultaneously measure blood flow rates at different measurement depths and simultaneously record the blood flow rate for each measurement depth.
【００１９】この場合、送光部から異なる距離にある受
光部を、送光部からの距離ごとに複数設け、それら複数
の受光部での受光光を合わせて送光部からの当該距離に
おける受光部の血流量を求めることにより、測定部位の
位置ずれに影響されることなく、再現性の高い測定結果
を得ることが可能となる。In this case, a plurality of light-receiving units located at different distances from the light-transmitting unit are provided for each distance from the light-transmitting unit, and the light received by the plurality of light-receiving units is combined to receive light at the distance from the light-transmitting unit. By obtaining the blood flow rate in the region, it is possible to obtain highly reproducible measurement results without being affected by the displacement of the measurement site.
【００２０】また、本発明において、送光部から被検体
に入射させるレーザー光のパワーを変えると、それによ
っても血流測定の測定深度を変えることが可能となる。
そこで、送光部からの距離が異なる複数の受光部で受光
することに加えて、レーザー光のパワーを変えることに
より、広範囲の測定深度の血流量を同時に測定すること
が可能となる。Further, in the present invention, by changing the power of the laser light that is incident on the subject from the light transmitting section, it is possible to change the measurement depth for blood flow measurement.
Therefore, in addition to light reception by a plurality of light receiving units having different distances from the light transmitting unit, it is possible to simultaneously measure blood flow in a wide measurement depth by changing the power of laser light.
【００２１】したがって、本発明によれば、皮膚組織の
状態分析を正確に行うことが可能となる。例えば、比較
的浅い部位に位置する細小血管の血流量と比較的深い部
位に位置する細動脈周辺の血流量とをそれぞれ把握する
ことができ、血流量と皮膚温度との相関関係を合理的に
解析することが可能となる。よって、皮膚に塗布した化
粧料の有効性評価、マッサージの有効性評価、皮膚組織
の老化の評価等を行うことが可能となる。Therefore, according to the present invention, it is possible to accurately analyze the state of the skin tissue. For example, the blood flow rate of small blood vessels located in a relatively shallow region and the blood flow rate around arterioles located in a relatively deep region can be grasped respectively, and the correlation between blood flow rate and skin temperature can be rationalized. It becomes possible to analyze. Therefore, it becomes possible to evaluate the effectiveness of the cosmetic material applied to the skin, the effectiveness of massage, and the evaluation of aging of the skin tissue.
【００２２】[0022]
【実施例】以下、本発明を実施例に基づいて具体的に説
明する。EXAMPLES The present invention will be specifically described below based on examples.
【００２３】図１は、本発明の方法を実施する装置例の
ブロック図（同図（ａ））及びそのセンサ部１０の底面
図（センサ部の被検体への接触面側からみた図）の説明
図（同図（ｂ））である。FIG. 1 is a block diagram of an example of an apparatus for carrying out the method of the present invention (FIG. 1 (a)) and a bottom view of the sensor section 10 (a view of the sensor section as seen from the contact surface side to the subject). It is explanatory drawing (the same figure (b)).
【００２４】この装置は、基本的には、従来のレーザー
ドップラー方式の血流測定装置と同様に、レーザー光を
発する光源部１１、光源部１１からのレーザーパワーを
調整するレーザーパワー調整手段１２、レーザーパワー
調整手段１２で調整されたレーザー光を被検体に入射さ
せ、被検体からの散乱光を受光するセンサ部１０、光源
部１１と一体的に配され、センサ部１０からの光を血流
信号に変換する信号処理手段１３（１３ａ〜１３ｅ）、
信号処理手段１３（１３ａ〜１３ｅ）からの信号に基づ
いて測定結果を表示するＸＹレコーダ、ＣＲＴ等の表示
手段１４を有している。また、このセンサ部１０は、被
検体にレーザー光を送光する送光部１６と被検体からの
散乱光を受光する受光部１５（１５ａ〜１５ｅ）とを有
している。そしてこの送光部１６は、レーザーパワー調
整手段１２からのレーザ光を導光する送光用光ファイバ
ー２をプローブ支持部材５に固定し、その光ファイバー
の端面を露出させたものから構成されており、受光部１
５（１５ａ〜１５ｅ）は、皮膚からの散乱光を信号処理
手段１３（１３ａ〜１３ｅ）に導光する受光用光ファイ
バー３（３ａ〜３ｅ）をプローブ支持部材５に固定し、
その光ファイバーの端面を露出させたものから構成され
ている。This device is basically similar to the conventional laser Doppler type blood flow measuring device, and includes a light source section 11 for emitting a laser beam and a laser power adjusting means 12 for adjusting the laser power from the light source section 11. The laser light adjusted by the laser power adjusting means 12 is made incident on the subject, and is integrated with the sensor unit 10 and the light source unit 11 that receive scattered light from the subject, and the light from the sensor unit 10 is passed through the bloodstream. Signal processing means 13 (13a to 13e) for converting into a signal,
It has a display means 14 such as an XY recorder or a CRT for displaying the measurement result based on the signals from the signal processing means 13 (13a to 13e). The sensor unit 10 also includes a light transmitting unit 16 that transmits laser light to the subject and a light receiving unit 15 (15a to 15e) that receives scattered light from the subject. The light transmitting unit 16 is configured by fixing the light transmitting optical fiber 2 for guiding the laser light from the laser power adjusting means 12 to the probe supporting member 5 and exposing the end face of the optical fiber. Light receiving part 1
5 (15a to 15e) fixes the light receiving optical fibers 3 (3a to 3e) for guiding the scattered light from the skin to the signal processing means 13 (13a to 13e) to the probe supporting member 5,
It is configured by exposing the end surface of the optical fiber.
【００２５】しかし、この装置のセンサ部１０には、送
光部１６からの距離が互いに異なる複数の受光部１５ａ
〜１５ｅが設けられている点で大きく特徴づけられる。
また、これら複数の受光部１５ａ〜１５ｅは、それぞれ
送光部１６からの距離が等しい複数の受光部（添字(-1)
〜(-8)）からなっている。即ち、送光部１６を中心とす
る径の異なる複数の同心円の円弧上にそれぞれ複数の受
光部が設けられたマルチアレイセンサとなっている。However, the sensor section 10 of this apparatus has a plurality of light receiving sections 15a which are different in distance from the light transmitting section 16.
It is characterized by the fact that ~ 15e is provided.
In addition, the plurality of light receiving units 15a to 15e are provided at the same distance from the light transmitting unit 16 (subscript (-1).
~ (-8)). That is, it is a multi-array sensor in which a plurality of light receiving portions are respectively provided on a plurality of concentric circular arcs having different diameters with the light transmitting portion 16 as the center.
【００２６】送光部１６から互いに異なる距離にある受
光部１５ａ〜１５ｅで受光された散乱光は、それぞれ信
号処理手段１３ａ〜１３ｅに送られ、送光部から所定距
離にある受光部での血流量として表示手段１４から出力
されるようになっている。したがって、この装置によれ
ば、測定深度の異なる血流量を同時に記録することが可
能となる。The scattered light received by the light receiving portions 15a to 15e at different distances from the light transmitting portion 16 is sent to the signal processing means 13a to 13e, respectively, and blood is received at the light receiving portions at a predetermined distance from the light transmitting portion. The flow rate is output from the display means 14. Therefore, according to this device, it is possible to simultaneously record blood flow rates having different measurement depths.
【００２７】ここで、送光部１６からの距離が互いに異
なる受光部１５ａ〜１５ｅでそれぞれ散乱光を受光する
ことにより、測定深度の異なる血流量を測定することが
できるのは、次のような原理に基づくものである。即
ち、図２に示したように、生体組織ｓの表面の点Ａを送
光部としてレーザー光を入射させると、この生体組織縦
断面内でのレーザー光の強度分布についての等強度分布
線は入射点Ａを中心とした半球状となる。これは、レー
ザー光の波長（ｎｍオーダー）に比して生体組織を構成
する細胞の大きさ（μｍオーダー）が大きいのでレーザ
ー光が散乱するためである。したがって、図２におい
て、点Ｅの強度は点Ｄの強度と等しいことになる。ま
た、点Ｅが、血流信号が得られる最大の深さである場合
に、点Ｄは血流信号が得られる組織表面での受光可能限
界点とる。よって、送光部を点Ａとし、受光部を点Ｂと
して血流測定を行う場合において、点Ｂで受光するとき
と同じ装置感度で血流信号を受光するときの受光可能限
界点Ｄと送光部Ａとの距離がＬ0であるとき、点Ｂを受
光部とする血流測定の組織内の測定範囲は、ａ＋ｂ＝Ｌ
0となる点Ｃの軌跡の半楕円体内であるということがで
きる。したがって、この場合の測定深度ｄは次式で表さ
れる。Here, it is possible to measure the blood flow rate at different measurement depths by receiving the scattered light by the light receiving sections 15a to 15e, which are different in distance from the light transmitting section 16, as follows. It is based on the principle. That is, as shown in FIG. 2, when the laser light is made to enter using the point A on the surface of the living tissue s as the light transmitting portion, the isointensity distribution line about the intensity distribution of the laser light in the longitudinal section of the living tissue is It becomes a hemisphere centered on the incident point A. This is because the size of the cells forming the biological tissue (on the order of μm) is larger than the wavelength of the laser light (on the order of nm), so that the laser light is scattered. Therefore, in FIG. 2, the intensity at point E is equal to the intensity at point D. Further, when the point E is the maximum depth at which the blood flow signal is obtained, the point D is the light receiving limit point on the tissue surface where the blood flow signal is obtained. Therefore, in the case where blood flow measurement is performed with the light transmitting unit as the point A and the light receiving unit as the point B, the light receiving limit point D and the light receiving limit point when receiving the blood flow signal with the same device sensitivity as when receiving the light at the point B are transmitted. When the distance from the light part A is L 0 , the measurement range in the tissue for blood flow measurement with the point B as the light receiving part is a + b = L
It can be said that it is within the semi-ellipsoid of the locus of the point C that becomes 0 . Therefore, the measurement depth d in this case is expressed by the following equation.
【００２８】[0028]
【数１】 （式中、ａは点Ａと点Ｃとの距離であり、ｂは点Ｃと点
Ｂとの距離であり、Ｌは点Ａと点Ｂとの距離である） よって、送光部と受光部との距離Ｌを小さくすることに
より測定深度を深くすることができ、逆に送光部と受光
部との距離Ｌを大きくすることにより測定深度を浅くす
ることができる。さらに、組織表面上で血流信号の受光
可能限界点Ｄと送光部Ａとの距離Ｌ0 を求めておくこと
により、上記の式に基づいて測定深度ｄの絶対値を推定
することが可能となる。[Equation 1] (In the formula, a is the distance between the points A and C, b is the distance between the points C and B, and L is the distance between the points A and B.) The measurement depth can be made deeper by decreasing the distance L to the section, and conversely, the measurement depth can be made shallower by increasing the distance L between the light transmitting section and the light receiving section. Further, by obtaining the distance L 0 between the light receiving limit point D of the blood flow signal and the light transmitting section A on the tissue surface, the absolute value of the measurement depth d can be estimated based on the above equation. Becomes
【００２９】また、図１に示したセンサ部１０において
は、上述のように送光部１６からの距離が互いに異なる
受光部１５ａ〜１５ｅが、それぞれ複数の受光部（添字
(-1)〜(-8)）からなっているが、この装置では、これら
送光部１６からの距離が同一である複数の受光部で受光
された光を合わせ、送光部からの距離ごとの血流信号と
して変換する。したがって、受光部の位置ずれによる血
流信号の再現性の低下を抑制できる。よって、送光部１
６からの距離が互いに異なる受光部での血流信号（即
ち、各測定深度の血流信号）が、それぞれ再現性高く得
られることとなる。Further, in the sensor section 10 shown in FIG. 1, as described above, the light receiving sections 15a to 15e having different distances from the light transmitting section 16 respectively include a plurality of light receiving sections (subscripts).
(-1) to (-8)), this device combines lights received by a plurality of light-receiving units having the same distance from the light-transmitting unit 16 to obtain a distance from the light-transmitting unit. It is converted as a blood flow signal for each. Therefore, it is possible to suppress a decrease in reproducibility of the blood flow signal due to the position shift of the light receiving unit. Therefore, the light transmitting unit 1
The blood flow signals (that is, the blood flow signals at the respective measurement depths) at the light receiving portions having different distances from 6 are obtained with high reproducibility.
【００３０】このように送光部からの距離ごとに複数の
受光部を設けるための具体的構成としては、送光部から
の距離ごとに複数の受光用光ファイバー３ａ〜３ｅ（添
字(-1)〜(-8)）を使用し、それらをまとめて各信号処理
手段１３ａ〜１３ｅ内の受光器に入れればよい。なお、
同図においては、送光部からの距離ごとに受光用光ファ
イバーをそれぞれ８個（３ａ〜３ｅ各々につき添字(-1)
〜(-8)）使用した例を示したが、送光部からの距離ごと
に設ける受光部の数に特に制限はない。As a specific configuration for providing a plurality of light receiving units for each distance from the light transmitting unit, a plurality of light receiving optical fibers 3a to 3e (subscript (-1) are provided for each distance from the light transmitting unit). .About. (-8)), these may be put together in a light receiver in each of the signal processing means 13a to 13e. In addition,
In the figure, eight optical fibers for receiving light are provided for each distance from the light transmitting unit (subscript (-1) for each of 3a to 3e).
~ (-8)) An example of use is shown, but the number of light receiving units provided for each distance from the light transmitting unit is not particularly limited.
【００３１】また、図１に示した装置においては、レー
ザーパワー調整手段１２により送光部１６に入射させる
レーザーパワーを調整することができるので、これによ
っても測定深度を変えることができ、測定深度の異なる
血流量を同時に記録することが可能となる。即ち、送光
部１６に入射させるレーザー光のパワーを大きくする程
測定深度を深くすることができる。Further, in the apparatus shown in FIG. 1, the laser power adjusting means 12 can adjust the laser power to be incident on the light transmitting section 16, so that the measuring depth can be changed, and the measuring depth can be changed. It is possible to simultaneously record different blood flow rates. That is, the measurement depth can be increased as the power of the laser light incident on the light transmitting unit 16 is increased.
【００３２】ここで、レーザーパワー調整手段１２とし
ては、例えば、光ファイバー用のアッテネータ、光源部
の出力を直接増幅又は減少させるもの等を使用すること
ができ、特に、挿入損失の少ない半減衰器を好ましく使
用することができる。Here, as the laser power adjusting means 12, for example, an attenuator for an optical fiber, a means for directly amplifying or reducing the output of the light source portion, or the like can be used, and in particular, a half attenuator with a small insertion loss is used. It can be preferably used.
【００３３】以上のように、この装置によれば、送光部
１６からの距離が異なる複数の受光部１５（１５ａ〜１
５ｅ）が設けられていること、及びレーザーパワー調整
手段１２により送光部に入射させるレーザー光のパワー
を変えられることから、種々の測定深度の血流量を同時
に記録することが可能となる。したがって、図３に示し
たような、レーザーパワーもしくは送光部と受光部との
距離Ｌと測定深度との関係を把握することが可能とな
る。また、年齢、性状等の異なる種々の被検体の測定深
度ごとの血流量をデータベースとして蓄積することによ
り、例えば図４に示したような測定深度と血流量と皮膚
の性状との関係を得ることができる。よって、このよう
なデータベースを蓄積後、新たに被検体の血流測定を測
定深度ごとに行い、蓄積データと比較解析することによ
り、容易に皮膚血流分布と老化度との関係を求め、皮膚
の老化度を評価することが可能となる。As described above, according to this device, the plurality of light receiving portions 15 (15a-1 to 15a-1) having different distances from the light transmitting portion 16 are provided.
5e) is provided and the laser power adjusting means 12 can change the power of the laser light to be incident on the light transmitting section, so that it becomes possible to simultaneously record blood flow rates at various measurement depths. Therefore, it becomes possible to grasp the relationship between the laser power or the distance L between the light transmitter and the light receiver and the measurement depth as shown in FIG. Further, by accumulating the blood flow rate for each measurement depth of various subjects having different ages and properties as a database, for example, the relationship between the measurement depth, the blood flow rate, and the skin property as shown in FIG. 4 can be obtained. You can Therefore, after accumulating such a database, the blood flow of the subject is newly measured for each measurement depth, and by comparing and analyzing the accumulated data, the relationship between the skin blood flow distribution and the aging degree is easily obtained, It is possible to evaluate the aging degree of.
【００３４】図５は、図１の装置を用いて送光部１６か
ら５．０ｍＷ〜０．２５ｍＷのヘリウム−ネオンレーザ
ー光を人第３指第１関節手掌部に照射し、受光部１５ａ
〜１５ｅ（送光部と送光部に最も近い受光部との間隔１
２５μｍ、各受光部間の間隔１２５μｍ）で受光するこ
とにより得た血流波形図である。この血流波形測定時に
は、上腕圧迫を所定時間行った。In FIG. 5, 5.0 mW to 0.25 mW of helium-neon laser light is emitted from the light transmitting unit 16 to the palm portion of the third finger and the first joint using the apparatus of FIG.
-15e (Gap 1 between the light transmitter and the light receiver closest to the light transmitter 1
FIG. 25 is a blood flow waveform diagram obtained by receiving light at 25 μm and an interval of 125 μm between each light receiving unit. When measuring the blood flow waveform, upper arm compression was performed for a predetermined time.
【００３５】また、図６（ａ）は、上腕圧迫を行った場
合に、一般に観察される深部皮膚血流の波形図である。
同図のように、深部皮膚血流には、脈波が大きく認めら
れ（ｘ部分）、止血開放後に反応性充血が認められ（ｙ
部分）、振幅が大きいという特徴がある。また、図６
（ｂ）は、同様の場合に観察される浅部皮膚血流の波形
図であり、脈波がほとんど認められず（ｘ部分）、ノイ
ズの多い波形となるという特徴がある。FIG. 6A is a waveform diagram of deep skin blood flow generally observed when the upper arm is compressed.
As shown in the figure, a large pulse wave was observed in the deep skin blood flow (x part), and reactive hyperemia was observed after the hemostasis was released (y).
(Part), the amplitude is large. In addition, FIG.
(B) is a waveform diagram of superficial skin blood flow observed in the same case, and is characterized in that almost no pulse wave is observed (x portion) and the waveform becomes noisy.
【００３６】図６を参照しつつ図５の結果を考察するこ
とにより、レーザーパワーが一定の場合には、送光部と
受光部との距離（ファイバー間隔）が狭くなるにしたが
ってより深い血流信号が観察されるのに対し、ファイバ
ー間隔が広くなるにしたがってより浅い血流信号が観察
されることがわかる。また、ファイバー間隔が一定の場
合には、レーザーパワーが高くなるにしたがってより深
い血流信号が観察されるのに対し、レーザーパワーが低
くなるにしたがってより浅い血流信号が観察されること
がわかる。By considering the results of FIG. 5 with reference to FIG. 6, when the laser power is constant, a deeper blood flow is obtained as the distance (fiber interval) between the light transmitting section and the light receiving section becomes narrower. It can be seen that the signal is observed, whereas a shallower blood flow signal is observed as the fiber spacing increases. In addition, when the fiber spacing is constant, deeper blood flow signals are observed as the laser power increases, whereas shallower blood flow signals are observed as the laser power decreases. .
【００３７】以上、図１に示した実施例の装置を例とし
て本発明を詳細に説明したが、この他に本発明は種々の
態様をとることができる。例えば、図１に示した装置で
は、センサ部１０として、一つの送光部１６と、その送
光部１６を中心として径の異なる複数の同心円の円弧上
にそれぞれ複数設けられた受光部１５ａ(-1 〜-8) 〜１
５ｅ(-1 〜-8) とを有するマルチアレイセンサを示した
が、センサ部１０における送光部１６の個数は一つに限
られない。Although the present invention has been described in detail above by taking the apparatus of the embodiment shown in FIG. 1 as an example, the present invention can take various modes other than this. For example, in the apparatus shown in FIG. 1, as the sensor unit 10, one light transmitting unit 16 and a plurality of light receiving units 15a (around the light transmitting unit 16 are provided on a plurality of concentric circular arcs having different diameters). -1 to -8) to 1
Although the multi-array sensor having 5e (-1 to -8) is shown, the number of the light transmitting units 16 in the sensor unit 10 is not limited to one.
【００３８】[0038]
【発明の効果】本発明によれば、皮膚表層の浅い部位か
ら深い部位に至る広い深度範囲の血流量をそれぞれの深
度ごとに同時に記録することが可能となり、皮膚組織に
おける血流量の変化を正確に解析することが可能とな
る。According to the present invention, it is possible to simultaneously record the blood flow rate in a wide depth range from a shallow portion to a deep portion of the skin surface layer for each depth, and to accurately change the blood flow rate in the skin tissue. It becomes possible to analyze.
【図１】実施例の装置のブロック図（同図（ａ））及び
そのセンサ部の底面図（同図（ｂ））である。FIG. 1 is a block diagram of an apparatus according to an embodiment (FIG. 1A) and a bottom view of a sensor section thereof (FIG. 1B).
【図２】送光部と受光部との距離と測定深度との関係の
説明図である。FIG. 2 is an explanatory diagram of a relationship between a distance between a light transmitting unit and a light receiving unit and a measurement depth.
【図３】レーザーパワー、送光部と受光部との距離、及
び測定深度の関係図である。FIG. 3 is a relationship diagram of laser power, a distance between a light transmitting unit and a light receiving unit, and a measurement depth.
【図４】測定深度と血流量と皮膚の性状との関係図であ
る。FIG. 4 is a relationship diagram of measurement depth, blood flow, and skin properties.
【図５】測定深度ごとの血流波形図である。FIG. 5 is a blood flow waveform diagram for each measurement depth.
【図６】一般的な深部皮膚血流の波形図（同図（ａ））
及び浅部皮膚血流の波形図（同図（ｂ））である。FIG. 6 is a general waveform diagram of deep skin blood flow (FIG. 6 (a)).
FIG. 3B is a waveform diagram of shallow skin blood flow (FIG. 3B).
【図７】従来のセンサの底面図である。FIG. 7 is a bottom view of a conventional sensor.
【図８】従来のセンサの底面図である。FIG. 8 is a bottom view of a conventional sensor.
１ａ、１ｂ センサ ２ 送光用光ファイバー ３ 受光用光ファイバー ４ センサ素子 ５ プローブ支持部材 １０ センサ部 １１ 光源部 １２ レーザーパワー調整手段 １３ 信号処理手段 １４ 表示手段 １５ａ〜１５ｅ 受光部 １６ 送光部 1a, 1b Sensor 2 Optical fiber for light transmission 3 Optical fiber for light reception 4 Sensor element 5 Probe support member 10 Sensor part 11 Light source part 12 Laser power adjusting means 13 Signal processing means 14 Display means 15a-15e Light receiving part 16 Light transmitting part
フロントページの続き (72)発明者 神谷 哲朗 栃木県宇都宮市大和３−19−６ (72)発明者 斎藤 建夫 石川県金沢市粟崎町２−７ バイオメディ カルサイエンス株式会社内Front page continuation (72) Inventor Tetsuro Kamiya 3-19-6 Yamato, Utsunomiya City, Tochigi Prefecture (72) Inventor Takeo Saito 2-7 Awazakicho, Kanazawa City, Ishikawa Prefecture Biomedical Science Co., Ltd.
Claims (7)
内で散乱した光を受光して被検体の血流量を測定するレ
ーザードップラー方式の血流測定方法において、被検体
にレーザ光を入射させる少なくとも一つの送光部に対
し、該送光部からの距離が異なる複数の位置を受光部と
し、各受光部で被検体からの散乱光を受光してそれぞれ
の受光部における血流量を測定し、それにより測定深度
の異なる血流量を同時に記録することを特徴とする血流
測定方法。1. A laser Doppler blood flow measuring method in which a laser beam is incident on a subject and the light scattered in the subject is received to measure the blood flow in the subject. With respect to at least one light-transmitting unit, a plurality of positions with different distances from the light-transmitting unit are used as light-receiving units, and each light-receiving unit receives scattered light from the subject and measures the blood flow in each light-receiving unit. A blood flow measuring method is characterized by simultaneously recording blood flow volumes having different measurement depths.
送光部からの距離ごとに複数設け、それら複数の受光部
における受光光を合わせて当該距離における血流量を測
定する請求項１記載の血流測定方法。2. A light-receiving unit at a different distance from the light-transmitting unit,
2. The blood flow measuring method according to claim 1, wherein a plurality of light receiving units are provided for each distance from the light transmitting unit, and the light receiving amounts of the plurality of light receiving units are combined to measure the blood flow at the distance.
を変化させ、異なるパワーの入射レーザー光ごとに血流
量を測定する請求項１又は２記載の血流測定方法。3. The blood flow measuring method according to claim 1, wherein the power of the laser light incident on the subject is changed, and the blood flow is measured for each of the incident laser lights having different powers.
せられたレーザー光を被検体に入射させ、被検体からの
散乱光を受光するセンサ部、センサ部からの信号を血流
信号に変換する信号処理手段、信号処理手段からの信号
に基づいて測定結果を表示する表示手段を有する血流測
定装置において、センサ部が、被検体にレーザー光を入
射させる少なくとも一つの送光部と、被検体からの散乱
光を受光する複数の受光部とを有し、かつそれら複数の
受光部は送光部から互いに異なる距離に設けられている
ことを特徴とする血流測定装置。4. A light source section that emits laser light, a sensor section that receives laser light emitted by the light source section on a subject, and receives scattered light from the subject, and a signal from the sensor section is converted into a blood flow signal. In the blood flow measuring device having the signal processing means for displaying the measurement result based on the signal from the signal processing means, the sensor part includes at least one light transmitting part for making the laser beam incident on the subject, A blood flow measuring device, comprising: a plurality of light receiving portions that receive scattered light from a specimen, and the plurality of light receiving portions are provided at different distances from the light transmitting portion.
のパワーを調整するレーザーパワー調整手段が設けられ
ている請求項４記載の血流測定装置。5. The blood flow measuring device according to claim 4, further comprising laser power adjusting means for adjusting the power of the laser light incident on the subject.
に複数の受光部を有し、これら複数の受光部での受光光
を合わせ、送光部から当該距離にある受光部の血流量が
得られるようにした請求項４又は５記載の血流測定装
置。6. The sensor unit has a plurality of light receiving units for different distances from the light transmitting unit, and the received light at the plurality of light receiving units is combined to obtain a blood flow amount of the light receiving unit at the distance from the light transmitting unit. The blood flow measuring device according to claim 4 or 5, wherein
の中央部に送光部を有し、その送光部を中心とする径の
異なる複数の同心円の円弧上にそれぞれ複数の受光部を
有するマルチアレイセンサである請求項６記載の血流測
定装置。7. The sensor section has a light-transmitting section at the center of the contact surface with respect to the subject, and a plurality of light-receiving sections are provided on each of a plurality of concentric circular arcs having different diameters centered on the light-transmitting section. The blood flow measuring device according to claim 6, which is a multi-array sensor having the same.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP06339594A JP3109066B2 (en) | 1994-12-28 | 1994-12-28 | Blood flow measurement method and blood flow measurement device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP06339594A JP3109066B2 (en) | 1994-12-28 | 1994-12-28 | Blood flow measurement method and blood flow measurement device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH08182658A true JPH08182658A (en) | 1996-07-16 |
| JP3109066B2 JP3109066B2 (en) | 2000-11-13 |
Family
ID=18328961
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP06339594A Expired - Fee Related JP3109066B2 (en) | 1994-12-28 | 1994-12-28 | Blood flow measurement method and blood flow measurement device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3109066B2 (en) |
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