JPH0528134B2 - - Google Patents
Info
- Publication number
- JPH0528134B2 JPH0528134B2 JP62281490A JP28149087A JPH0528134B2 JP H0528134 B2 JPH0528134 B2 JP H0528134B2 JP 62281490 A JP62281490 A JP 62281490A JP 28149087 A JP28149087 A JP 28149087A JP H0528134 B2 JPH0528134 B2 JP H0528134B2
- Authority
- JP
- Japan
- Prior art keywords
- blood flow
- light
- monitoring device
- receiving elements
- subject
- Prior art date
- Legal status (The legal status 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 status listed.)
- Expired - Lifetime
Links
- 230000017531 blood circulation Effects 0.000 claims description 32
- 238000012806 monitoring device Methods 0.000 claims description 8
- 230000002123 temporal effect Effects 0.000 claims description 8
- 230000001678 irradiating effect Effects 0.000 claims description 3
- 238000010586 diagram Methods 0.000 description 6
- 239000000523 sample Substances 0.000 description 5
- 238000000034 method Methods 0.000 description 4
- 230000004043 responsiveness Effects 0.000 description 3
- 210000004369 blood Anatomy 0.000 description 2
- 239000008280 blood Substances 0.000 description 2
- 210000000601 blood cell Anatomy 0.000 description 2
- 238000001514 detection method Methods 0.000 description 2
- 239000000835 fiber Substances 0.000 description 2
- 239000013307 optical fiber Substances 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- 238000012935 Averaging Methods 0.000 description 1
- 230000005856 abnormality Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000006870 function Effects 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 230000003836 peripheral circulation Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
Landscapes
- Measuring Pulse, Heart Rate, Blood Pressure Or Blood Flow (AREA)
Description
【発明の詳細な説明】
［産業上の利用分野］
本発明は、レーザースペツクル法を用いて、被
検体表面の平均血流の変化を、経時的に測定し得
るようにした血流モニタ装置に関するものであ
る。Detailed Description of the Invention [Industrial Application Field] The present invention provides a blood flow monitoring device that can measure changes in the average blood flow on the surface of a subject over time using the laser speckle method. It is related to.
［発明の背景］
レーザー光を皮膚などの生体組織に向けて照射
すると、生体を構成する粒子によつて散乱された
光が干渉しあつて、反射散乱光にランダムな模様
つまりスペツクルパターンが現われる。更に、こ
のスペツクルパターンが毛細血管内の血球粒子の
移動に伴つて刻々と変化するために、或る一点で
の光強度の時間的変動を測定すると、血液速度を
反映した雑音性の信号が現われる。この現象は
1975年頃からM.D.Sternらによつて見い出され、
スペツクル信号の周波数解析によつて皮膚血流な
どを無侵襲で測定できるために急速に研究が進
み、一部でレーザードプラ血流計と呼ばれて市販
されている。[Background of the Invention] When laser light is irradiated towards living tissue such as the skin, the light scattered by the particles that make up the living body interfere with each other, and a random pattern, or speckled pattern, appears in the reflected and scattered light. . Furthermore, because this speckle pattern changes moment by moment as the blood cells move within the capillary, measuring temporal fluctuations in light intensity at a single point produces a noisy signal that reflects the blood velocity. appear. This phenomenon is
It was discovered around 1975 by MDStern et al.
Since it is possible to measure blood flow in the skin non-invasively by frequency analysis of speckle signals, research has progressed rapidly, and some devices are commercially available as laser Doppler blood flow meters.
従来まで提案されてきた方法では、光フアイバ
プローブなど用いて、或る観測点での血流の時間
的変化を追跡したり、他の標準点でのデータと比
較して異常を見い出すなどの手法が採られてい
る。従来の光フアイバプローブを用いたレーザー
ドプラー血流計では、検出面積が直径数mm2程度し
かないために、測定する場所によつて値がばらつ
き、或る面積について血流を評価するには不適当
である。更に、フアイバプローブから得られる信
号は元来雑音性のものであり、これを平滑化して
表示するため、積分回路やローパスフイルタが必
ず組み込まれている。これらの回路の時定数を大
きくすれば、血流の変化を穏やかに捕えることが
できるが、血流の急激な変化に対する応答性が低
下する。 Previously proposed methods involve tracking temporal changes in blood flow at a certain observation point using optical fiber probes, and comparing data with data from other standard points to find abnormalities. is taken. With conventional laser Doppler blood flowmeters that use optical fiber probes, the detection area is only a few mm2 in diameter, so the values vary depending on the measurement location, making it difficult to evaluate blood flow in a certain area. Appropriate. Furthermore, the signal obtained from the fiber probe is inherently noisy, and in order to smooth it and display it, an integrating circuit and a low-pass filter are always included. If the time constants of these circuits are increased, changes in blood flow can be detected gently, but responsiveness to rapid changes in blood flow is reduced.
しかし、一方で組織上の或る面積に渡つて血流
量の二次元的マツプを概観できれば、組織全体の
末梢循環機能の良否を一目で把握することがで
き、臨床上極めて有用な情報が与えられることに
なる。このために、本出願人は既にイメージセン
サを用いた血流分布表示装置を提案し、実用化を
進めているが、血流の経時的変化を細かく追跡し
たいという要望も根強いものがある。 However, if we can obtain an overview of a two-dimensional map of blood flow over a certain area of tissue, we can grasp at a glance the quality of the peripheral circulation function of the entire tissue, providing extremely useful information clinically. It turns out. To this end, the present applicant has already proposed a blood flow distribution display device using an image sensor and is putting it into practical use, but there is still a deep-rooted desire to closely track changes in blood flow over time.
［発明の目的］
本発明の目的は、レーザースペツクル法にイメ
ージセンサを応用して、血流の変化に対する応答
性の優れた血流モニタ装置を提供することにあ
る。[Object of the Invention] An object of the present invention is to provide a blood flow monitoring device with excellent responsiveness to changes in blood flow by applying an image sensor to the laser speckle method.
［発明の概要］
上述の目的を達成するための本発明の要旨は、
被検体にレーザー光を照射する照射手段と、被検
体からの反射光を受光するための多数個の受光素
子を配列した受光手段と、該受光手段で得られた
前記受光素子の出力を記憶する記憶手段と、該記
憶手段の記憶内容から前記受光素子ごとの時間的
変化率をを求め、更に該時間的変化率を前記多数
個の受光素子について平均した値を求めて血流値
の経時的変化を演算する演算手段と、該演算手段
により求めた前記被検体のレーザー光照射部位に
おける血流値の前記経時的変化を表示する表示手
段とを具備することを特徴とする血流モニタ装置
である。[Summary of the invention] The gist of the present invention for achieving the above object is as follows:
An irradiation means for irradiating a laser beam onto a subject, a light receiving means having a plurality of light receiving elements arranged to receive reflected light from the subject, and an output of the light receiving element obtained by the light receiving means being stored. A storage means, and a temporal change rate for each of the light receiving elements is determined from the memory contents of the storage means, and a value obtained by averaging the temporal change rates for the plurality of light receiving elements is calculated, and the blood flow value is determined over time. A blood flow monitoring device comprising a calculation means for calculating the change, and a display means for displaying the change over time in the blood flow value at the laser beam irradiated site of the subject determined by the calculation means. be.
［発明の実施例］
本発明を図示の実施例に基づいて詳細に説明す
る。[Embodiments of the Invention] The present invention will be described in detail based on illustrated embodiments.
第１図はその概略的な説明図であり、レーザー
光をシリンドリカルレンズなどによつて例えば数
cmの長さの線状に広げて皮膚面Ｓに照射し、反射
光を受光レンズ１を介して多数の受光素子を配列
した一次元ラインセンサ２上に結像する。ライン
センサ２の受光面には、上述したようなスペツク
ルパターンが生じ、これが被検体内の血球の移動
に伴つて刻々と模様を変えるため、ラインセンサ
２の出力は走査の度に異なつたものとなる。 Figure 1 is a schematic explanatory diagram of the method.
The light is spread out into a line with a length of cm and irradiated onto the skin surface S, and the reflected light is imaged through a light receiving lens 1 onto a one-dimensional line sensor 2 in which a large number of light receiving elements are arranged. The above-mentioned speckle pattern occurs on the light receiving surface of the line sensor 2, and this pattern changes moment by moment as blood cells move within the subject, so the output of the line sensor 2 differs each time it scans. becomes.
第２図ａは同じ個所にレーザー光を照射しなが
ら、ラインセンサ２を２回続けて走査したときに
得られた出力信号であり、血流値の高い時点での
データである。ｂは同様に血流値の低いう時点に
相当する。第２図ａでは血流によるパターンの変
動が激しいため、１回目の走査出力と２回目の出
力の間に大きな差が生じているが、ｂでは変動が
緩慢なために差が小さくなつていることが判る。
この差を全画素について積算すると、その値はａ
においては高く、ｂにおいては低くなる。この演
算を高速で行うことによつて、或る観測線上の平
均血流の時間的変化を追跡することが可能にな
る。 FIG. 2a shows an output signal obtained when the line sensor 2 is scanned twice in succession while irradiating the same location with laser light, and is data at a time when the blood flow value is high. Similarly, b corresponds to the time point when the blood flow value is low. In Figure 2 a, there is a large difference between the first and second scanning outputs because the pattern fluctuates rapidly due to blood flow, but in b the difference is small because the fluctuations are slow. I understand that.
When this difference is integrated for all pixels, the value is a
It is high at , and low at b. By performing this calculation at high speed, it becomes possible to track temporal changes in the average blood flow on a certain observation line.
第３図は信号処理系の実施例のブロツク回路構
成図であり、ラインセンサ２の出力はビデオ増幅
器３、Ａ／Ｄ変換器４、メモリ５、CRTデイス
プレイ６に順次に接続され、各回路はマイクロコ
ンピユータ７と接続され、マイクロコンピユータ
７の出力により動作し、或いはマイクロコンピユ
ータ７との間で信号の送受信を行うようになつて
いる。ラインセンサ２の出力つまり画像信号をビ
デオ増幅器３で増幅し、高速Ａ／Ｄ変換器４でデ
ジタル化した後にメモリ５にデータを蓄積し、マ
イクロコンピユータ７に記憶しているプログラム
に従つて、同一画素において２つの連続した走査
出力の差を求める。これは、実際には次のような
演算によつて実行することができる。 FIG. 3 is a block circuit configuration diagram of an embodiment of the signal processing system, in which the output of the line sensor 2 is sequentially connected to a video amplifier 3, an A/D converter 4, a memory 5, and a CRT display 6. It is connected to the microcomputer 7 and operates based on the output of the microcomputer 7, or transmits and receives signals to and from the microcomputer 7. The output of the line sensor 2, that is, the image signal, is amplified by a video amplifier 3, digitized by a high-speed A/D converter 4, and then stored in a memory 5. Determine the difference between two successive scan outputs at a pixel. This can actually be performed by the following calculation.
いま、時刻ｔにおける走査出力をデジタル化し
て記憶し、Ｎ個のサンプルを得たとすると、これ
はその走査線上に存在するＮ個の観測点における
或る観測時間のスペツクル信号強度を表してい
る。時刻ｔとｔ＋Δtでの走査出力について、先
頭からｎ番目のサンプル値をそれぞれＩ（ｔ、
ｎ）、Ｉ（ｔ＋Δt、ｎ）とし、両者の差の絶対値
をサンプル総数Ｎについて積算した値、
Ｖ(t)＝N
〓n=1
｜Ｉ（ｔ、ｎ）−Ｉ（ｔ＋Δt、ｎ）
｜
を求めれば、Ｖ(t)は時刻ｔにおけるその観測線上
の平均血流値に比例する。この演算を高速に行
い、演算結果を刻々とCRTデイスプレイ６に時
系列に波形として或いは数値として表示したり、
レコーダに出力するなどして、血流値の経時変化
を測定することが可能となる。 Now, if the scanning output at time t is digitized and stored and N samples are obtained, this represents the speckle signal intensity at a certain observation time at N observation points existing on the scanning line. Regarding the scanning output at time t and t+Δt, the nth sample value from the beginning is expressed as I(t,
n), I(t+Δt, n), and the value obtained by integrating the absolute value of the difference between the two over the total number of samples N, V(t)= N 〓 n=1 | I(t, n) - I(t+Δt, n)
If | is found, V(t) is proportional to the average blood flow value on the observation line at time t. This calculation is performed at high speed, and the calculation results are displayed moment by moment on the CRT display 6 as waveforms or numerical values in chronological order.
By outputting to a recorder, it becomes possible to measure changes in blood flow values over time.
なお、実施例においては受光素子を一次元のラ
インセンサとしたが、これを二次元イメージセン
サとして二次元的に血流値の経時変化を求めるこ
ともできる。なお、この場合にはレーザ光は二次
元方向に広く照射することが必要となる。 In the embodiment, the light-receiving element is a one-dimensional line sensor, but it is also possible to use this as a two-dimensional image sensor to obtain two-dimensional changes in blood flow values over time. Note that in this case, it is necessary to irradiate the laser beam widely in two-dimensional directions.
［発明の効果］
以上説明したように本発明に係る血流モニタ装
置は、血流の経時的変化を表示し観察することが
できるので、医用分野において広く活用し得るも
のである。特に、フアイバプローブを利用したレ
ーザードプラ血流計に比べて、血流変化に対する
応答性が高く、かつ広い検出視野を有するなどの
長所がある。[Effects of the Invention] As explained above, the blood flow monitoring device according to the present invention can display and observe changes in blood flow over time, and therefore can be widely used in the medical field. In particular, compared to a laser Doppler blood flow meter using a fiber probe, it has advantages such as higher responsiveness to changes in blood flow and a wider detection field of view.
図面は本発明に係る皿流モニタ装置の一実施例
を示し、第１図は概略的説明図、第２図ａ，ｂは
得られた反射光の走査出力波形図、第３図は信号
処理系のブロツク回路構成図である。
符号１はレーザ光源、２はラインセンサ、３は
ビデオ増幅器、４はＡ／Ｄ変換器、５はメモリ、
６はCRTデイスプレイ、７はマイクロコンピユ
ータである。
The drawings show an embodiment of the dish flow monitoring device according to the present invention, in which Fig. 1 is a schematic explanatory diagram, Fig. 2 a and b are scanning output waveform diagrams of the obtained reflected light, and Fig. 3 is a signal processing diagram. FIG. 2 is a block circuit configuration diagram of the system. 1 is a laser light source, 2 is a line sensor, 3 is a video amplifier, 4 is an A/D converter, 5 is a memory,
6 is a CRT display, and 7 is a microcomputer.
Claims (1)
被検体からの反射光を受光するための多数個の受
光素子を配列した受光手段と、該受光手段で得ら
れた前記受光素子の出力を記憶する記憶手段と、
該記憶手段の記憶内容から前記受光素子ごとの時
間的変化率を求め、更に該時間的変化率を前記多
数個の受光素子について平均した値を求めて血流
値の経時的変化を演算する演算手段と、該演算手
段により求めた前記被検体のレーザー光照射部位
における血流値の前記経時的変化を表示する表示
手段とを具備することを特徴とする血流モニタ装
置。 ２ 前記受光手段は一次元ラインセンサとした特
許請求の範囲第１項に記載の血流モニタ装置。 ３ 前記受光手段は二次元イメージセンサとした
特許請求の範囲第１項に記載の血流モニタ装置。 ４ 前記表示手段はCRTデイスプレイとした特
許請求の範囲第１項に記載の血流モニタ装置。[Claims] 1. Irradiation means for irradiating a subject with laser light;
a light-receiving means having a plurality of light-receiving elements arranged for receiving reflected light from the subject; a storage means for storing the output of the light-receiving elements obtained by the light-receiving means;
calculating the temporal change rate of the blood flow value by determining the temporal change rate for each of the light receiving elements from the memory contents of the storage means, and further calculating the average value of the temporal change rate for the plurality of light receiving elements; and display means for displaying the change over time in the blood flow value at the laser beam irradiated site of the subject determined by the calculation means. 2. The blood flow monitoring device according to claim 1, wherein the light receiving means is a one-dimensional line sensor. 3. The blood flow monitoring device according to claim 1, wherein the light receiving means is a two-dimensional image sensor. 4. The blood flow monitoring device according to claim 1, wherein the display means is a CRT display.
Priority Applications (6)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62281490A JPH01124437A (en) | 1987-11-07 | 1987-11-07 | Blood flow monitor apparatus |
| AU12063/88A AU608807B2 (en) | 1987-03-03 | 1988-02-23 | Apparatus for monitoring bloodstream |
| US07/160,800 US4862894A (en) | 1987-03-03 | 1988-02-26 | Apparatus for monitoring bloodstream |
| CA000560135A CA1293535C (en) | 1987-03-03 | 1988-02-29 | Apparatus for monitoring bloodstream |
| DE8888301716T DE3875758T2 (en) | 1987-03-03 | 1988-02-29 | DEVICE FOR MONITORING THE BLOOD FLOW. |
| EP88301716A EP0282210B1 (en) | 1987-03-03 | 1988-02-29 | Apparatus for monitoring a bloodstream |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62281490A JPH01124437A (en) | 1987-11-07 | 1987-11-07 | Blood flow monitor apparatus |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH01124437A JPH01124437A (en) | 1989-05-17 |
| JPH0528134B2 true JPH0528134B2 (en) | 1993-04-23 |
Family
ID=17639913
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP62281490A Granted JPH01124437A (en) | 1987-03-03 | 1987-11-07 | Blood flow monitor apparatus |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH01124437A (en) |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7817256B2 (en) | 2006-02-22 | 2010-10-19 | Kyushu Institute Of Technology | Personal authentication method and personal authentication device utilizing finger-tip blood flow measurement by laser light |
| WO2010131550A1 (en) | 2009-05-13 | 2010-11-18 | 国立大学法人九州工業大学 | Blood flow image diagnosing device |
| US7844083B2 (en) | 2004-06-18 | 2010-11-30 | Kyushu Institute Of Technology | Method for acquiring personal identification data, personal identification method, apparatus for acquiring personal identification data, and personal identification apparatus |
| US8285003B2 (en) | 2006-06-07 | 2012-10-09 | Kyushu Institute Of Technology | Personal authentication method and personal authentication device utilizing ocular fundus blood flow measurement by laser light |
| US8494228B2 (en) | 2008-04-03 | 2013-07-23 | Kyushu Institute Of Technology | Personal authentication method using subcutaneous bloodstream measurement and personal authentication device |
| WO2014175154A1 (en) | 2013-04-23 | 2014-10-30 | ソフトケア有限会社 | Blood flow image diagnosis device and diagnosis method |
| WO2018003139A1 (en) | 2016-06-28 | 2018-01-04 | ソフトケア有限会社 | Blood flow dynamic imaging diagnosis device and diagnosis method |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6347689B1 (en) | 2000-06-30 | 2002-02-19 | Shimano Inc. | Roll back seal for disc brake |
| US6401882B1 (en) | 2000-06-30 | 2002-06-11 | Shimano Inc. | Heat insulator for disc brake |
| WO2010029768A1 (en) | 2008-09-11 | 2010-03-18 | トヨタ自動車株式会社 | Disc brake device |
| DE112018002304T5 (en) * | 2017-05-02 | 2020-02-27 | Sony Corporation | FLOW RATE MEASURING METHOD, FLOW RATE MEASURING DEVICE AND PROGRAM |
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|---|---|---|---|---|
| JPS59214772A (en) * | 1983-05-20 | 1984-12-04 | Hitachi Ltd | Method and apparatus for measuring flow velocity in fluid |
| JPS60203236A (en) * | 1984-03-28 | 1985-10-14 | キヤノン株式会社 | Laser speckle blood flow meter |
| JPS63214238A (en) * | 1987-03-03 | 1988-09-06 | 藤居 良子 | Blood flow distribution display apparatus |
-
1987
- 1987-11-07 JP JP62281490A patent/JPH01124437A/en active Granted
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS59214772A (en) * | 1983-05-20 | 1984-12-04 | Hitachi Ltd | Method and apparatus for measuring flow velocity in fluid |
| JPS60203236A (en) * | 1984-03-28 | 1985-10-14 | キヤノン株式会社 | Laser speckle blood flow meter |
| JPS63214238A (en) * | 1987-03-03 | 1988-09-06 | 藤居 良子 | Blood flow distribution display apparatus |
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7844083B2 (en) | 2004-06-18 | 2010-11-30 | Kyushu Institute Of Technology | Method for acquiring personal identification data, personal identification method, apparatus for acquiring personal identification data, and personal identification apparatus |
| US7817256B2 (en) | 2006-02-22 | 2010-10-19 | Kyushu Institute Of Technology | Personal authentication method and personal authentication device utilizing finger-tip blood flow measurement by laser light |
| US8285003B2 (en) | 2006-06-07 | 2012-10-09 | Kyushu Institute Of Technology | Personal authentication method and personal authentication device utilizing ocular fundus blood flow measurement by laser light |
| US8494228B2 (en) | 2008-04-03 | 2013-07-23 | Kyushu Institute Of Technology | Personal authentication method using subcutaneous bloodstream measurement and personal authentication device |
| WO2010131550A1 (en) | 2009-05-13 | 2010-11-18 | 国立大学法人九州工業大学 | Blood flow image diagnosing device |
| US9028421B2 (en) | 2009-05-13 | 2015-05-12 | Kyushu Institute Of Technology | Blood flow image diagnosing device |
| WO2014175154A1 (en) | 2013-04-23 | 2014-10-30 | ソフトケア有限会社 | Blood flow image diagnosis device and diagnosis method |
| US10098592B2 (en) | 2013-04-23 | 2018-10-16 | Softcare Co., Ltd. | Blood flow image diagnosing device and method |
| WO2018003139A1 (en) | 2016-06-28 | 2018-01-04 | ソフトケア有限会社 | Blood flow dynamic imaging diagnosis device and diagnosis method |
| US11330995B2 (en) | 2016-06-28 | 2022-05-17 | Softcare Co., Ltd. | Apparatus and method for imaging and analyzing hemodynamics |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH01124437A (en) | 1989-05-17 |
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