JPS60119417A - Fluid measuring method by nmr imaging device - Google Patents
Fluid measuring method by nmr imaging deviceInfo
- Publication number
- JPS60119417A JPS60119417A JP58227187A JP22718783A JPS60119417A JP S60119417 A JPS60119417 A JP S60119417A JP 58227187 A JP58227187 A JP 58227187A JP 22718783 A JP22718783 A JP 22718783A JP S60119417 A JPS60119417 A JP S60119417A
- Authority
- JP
- Japan
- Prior art keywords
- magnetic field
- blood vessel
- fid signal
- blood
- applying
- 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.)
- Granted
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
- G01F1/00—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow
- G01F1/704—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow using marked regions or existing inhomogeneities within the fluid stream, e.g. statistically occurring variations in a fluid parameter
- G01F1/708—Measuring the time taken to traverse a fixed distance
- G01F1/716—Measuring the time taken to traverse a fixed distance using electron paramagnetic resonance [EPR] or nuclear magnetic resonance [NMR]
Landscapes
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- General Physics & Mathematics (AREA)
- Measuring Volume Flow (AREA)
- Measuring Pulse, Heart Rate, Blood Pressure Or Blood Flow (AREA)
- Magnetic Resonance Imaging Apparatus (AREA)
Abstract
Description
【発明の詳細な説明】
（イ）産業−１−の利用分野
本発明はＮＭＲイメージング装置による流体計測法に係
り、特に流体を直接可視化することにより、その速度、
径路を正確にめ得るＮＭＲイメージング装置による流体
計測法に関する。Detailed Description of the Invention (a) Field of Application in Industry-1- The present invention relates to a fluid measurement method using an NMR imaging device, and in particular, by directly visualizing a fluid, its velocity,
This invention relates to a fluid measurement method using an NMR imaging device that can accurately measure a path.
（ロ）従来技術
ＮＭＲイメージンク装置による流体計測法（例えば血流
速）では、励起パルスで励起した励起スライス面上のＦ
ＴＤ信号の強度より流速を算出する方法が採用されてい
る。(b) In the fluid measurement method (for example, blood flow velocity) using a conventional NMR imaging device, F
A method is adopted in which the flow velocity is calculated from the intensity of the TD signal.
かかる方法では、計測する流体を直接に観察することが
不可能であり、またその計測精度にも問題がある。With this method, it is impossible to directly observe the fluid to be measured, and there are also problems with the measurement accuracy.
第１図は前記従来のＮＭＲイメージング装置による流体
計測法を説明するためのパルスシーケンス説明図である
。 以下、流体を血液としてまた、流管を血管として説
明してゆくものとする。FIG. 1 is a pulse sequence explanatory diagram for explaining a fluid measurement method using the conventional NMR imaging apparatus. Hereinafter, the fluid will be described as blood and the flow tube as a blood vessel.
すなわち、血管である流管に平行してＺ軸方向に一様な
磁束密度の磁場Ｉ（を与えておき、その血管に１８０°
パルスを与え、血液の核磁気モーメントを反転させ、所
定時間経過後に第１図に図示した９０°パルス及び前記
スライス面を得るための傾斜磁場すなわち、２方向の変
位に比例した硼界強度を持ち、その磁界の方向が前記磁
場１−１の方向と平行な傾斜磁場Ｇｚを与える。In other words, a magnetic field I (with a uniform magnetic flux density) is applied in the Z-axis direction parallel to the flow tube, which is a blood vessel, and the blood vessel is
A pulse is applied to reverse the nuclear magnetic moment of the blood, and after a predetermined period of time, a gradient magnetic field is applied to obtain the 90° pulse and the slice plane shown in FIG. , provides a gradient magnetic field Gz whose direction is parallel to the direction of the magnetic field 1-1.
その後、前記スライス面におけるＹ方向の情報を得る目
的で傾斜磁場Ｇｙすなわち、Ｙ方向の変位に比例した磁
界強度を持ち、その磁界の方向が前記磁場Ｈの方向と平
行な傾斜磁場Ｇｙを与えていわゆる位相コーディングを
行う。Then, in order to obtain information in the Y direction on the slice plane, a gradient magnetic field Gy is applied, that is, a gradient magnetic field Gy having a magnetic field intensity proportional to the displacement in the Y direction and whose direction is parallel to the direction of the magnetic field H. So-called phase coding is performed.
その後、Ｘ方向の変位に比例した磁界強度を持ち、その
磁界の方向が前記磁場■１の方向と平行な傾斜磁場Ｇｘ
を印加してＦＩＤ信号を取り出す方法である。この方法
はスピンワーブ法としてよく知られている。After that, a gradient magnetic field Gx having a magnetic field strength proportional to the displacement in the X direction and whose direction is parallel to the direction of the magnetic field (1)
In this method, the FID signal is extracted by applying the FID signal. This method is well known as the spinwarb method.
ずなわち、ＧｙではＹ方向の位相情報がまるのに対して
、ＧｘではＸ方向の周波数情報がまるものであるが、従
来技術では前記Ｇｘ印加の時点でＦＩＤ信号を取り出す
ものである。That is, in Gy, the phase information in the Y direction is rounded, whereas in Gx, the frequency information in the X direction is rounded, but in the conventional technology, the FID signal is extracted at the time of applying the Gx.
かかる方法では、前記Ｇｚは単にスライス面を決定する
のに使用するものであり、前記信号採取の時点ではＧｚ
はすでに消滅しているから、血液そのものの移動に関連
する情報は得られず、血管をながれる血液（流体）部分
の濃淡が速度を表したものとみなしているのであり、そ
の測定の精度は低いものである。In such a method, the Gz is simply used to determine the slice plane, and at the time of signal acquisition, the Gz
Since it has already disappeared, no information related to the movement of the blood itself can be obtained, and the density of the blood (fluid) flowing through the blood vessels is considered to represent the speed, and the accuracy of its measurement is low. It is something.
（ハ）目的
本発明は傾斜磁場Ｇｚはスライス面決定にあづがること
は勿論のこと、血管を流れる血液の移動に関連する情報
、すなわぢ、血液の流速乃至ば血管の変位を可視像とし
て認識でき、その測定の精度を高くできるＮＭＲイメー
ジング装置による流体計測法を提供することを目的とし
ている。(C) Purpose The present invention provides that the gradient magnetic field Gz not only assists in determining the slice plane, but also information related to the movement of blood flowing through blood vessels, such as the flow velocity of blood or the displacement of blood vessels. It is an object of the present invention to provide a fluid measurement method using an NMR imaging device that can be recognized as a visual image and can improve the measurement accuracy.
（ニ）構成
本発明は９０°パルスと傾斜磁場Ｇ２を加えて流管のス
ライス面を決定したあと、１頃斜磁場Ｇｘ及びＧｙを加
えて位相コーディングを行い、その後ＦＪＤ信号を採取
する流体計測法であって、前記傾斜磁場Ｇｚのある時点
において前記ＦＩＤ信号を採取するようにしたＮＭＲイ
メージング装置による流体計測法である。(D) Configuration The present invention applies a 90° pulse and a gradient magnetic field G2 to determine the slice plane of the flow tube, then applies gradient magnetic fields Gx and Gy around 1 to perform phase coding, and then collects the FJD signal. This is a fluid measurement method using an NMR imaging device in which the FID signal is collected at a certain point in the gradient magnetic field Gz.
（ホ）実施例
第２図は血管のスライス面を表す概念図、第３図は本発
明に係るＮＭＲイメージング装置による流体計測法に使
用する各種パルスのシーケンス図である。(E) Embodiment FIG. 2 is a conceptual diagram showing a slice plane of a blood vessel, and FIG. 3 is a sequence diagram of various pulses used in a fluid measurement method using an NMR imaging apparatus according to the present invention.
本発明を実施する場合の手順について説明する。The procedure for implementing the present invention will be explained.
■ Ｚ軸に沿った生体の血管１ｏに磁束密度が一様な静
磁場■１を与える。すなわち血管１ｏは静磁場Ｈに平行
である。■ Apply a static magnetic field ■1 with uniform magnetic flux density to the blood vessel 1o of the living body along the Z axis. That is, the blood vessel 1o is parallel to the static magnetic field H.
■ Ｚ軸に平行な傾斜磁場Ｇｚと９０”パルスを血管に
加える。この際必要であれば、９０”パルスを加エル前
に１８０°パルスを印加することもある。■ A gradient magnetic field Gz parallel to the Z axis and a 90" pulse are applied to the blood vessel. At this time, if necessary, a 180° pulse may be applied before applying the 90" pulse.
■ ■と■の手順により、血管のうちの特定の部分が選
択的に励起される。■ By the steps of ■ and ■, a specific part of the blood vessel is selectively excited.
■ ついで、Ｇｘ、 Ｇｙの傾斜磁場を加えることによ
り、前記スライス面のＸ方向、Ｙ方向の位相情報がまる
。(2) Then, by applying gradient magnetic fields of Gx and Gy, the phase information in the X and Y directions of the slice plane is rounded.
■ その後、前記１項斜磁場Ｇｚを反転する。(2) Thereafter, the first term oblique magnetic field Gz is reversed.
■ ＦＩＤ信号が採取されるが、この際重要なことは、
ＦＩＤ信号採取の時点においては前記傾斜磁場Ｇｚば継
続している。■ The FID signal is collected, but the important thing at this time is that
At the time of FID signal acquisition, the gradient magnetic field Gz continues.
■ サンプリングパルスを与え、ＦＩＤ信号をサンプリ
ングする。■ Give a sampling pulse and sample the FID signal.
■ ■〜■の手順を必要回数繰り返す。例えばこの繰り
返しを６４ Ｘ ６４回、Ｇｘ、 Ｇｙの位相コーディ
ングを変えながら反復するものとし、前記サンプリング
点を仮に６４であるとすると、合計６４ Ｘ ６４ ｘ
５４個のデータが得られる。■ Repeat steps from ■ to ■ as many times as necessary. For example, if this repetition is repeated 64 x 64 times while changing the phase coding of Gx and Gy, and if the sampling point is 64, then the total is 64 x 64 x.
54 pieces of data are obtained.
■ 前記サンプリングデータを３次元フーリエ変換する
ことにより、３次元の画像が得られる。(2) A three-dimensional image is obtained by subjecting the sampling data to three-dimensional Fourier transformation.
（へ）効果
以上■〜■の手順を考えると、スライス面の決定すなわ
ち、選択励起時点とＦＩＤ信号の受信時点の時間差によ
り血管を流れる血液部分は第２図に図示するように、ス
ライス面から抜き出た形となり、その速度を可視像とし
て認識することができる。また、前記受信までの時間を
種々変えることにより、血液（流体）の変位をめること
もできる。(To) Effects Above Considering the steps from ■ to ■, determining the slice plane, that is, depending on the time difference between the selective excitation time point and the reception time of the FID signal, the blood flowing through the blood vessel can be determined from the slice plane as shown in Figure 2. It becomes an extracted shape, and its speed can be recognized as a visible image. Furthermore, by varying the time until the reception, the displacement of blood (fluid) can be measured.
なお、傾斜磁場ＧｚをがけたことにょるＦＩＤ（３号の
分散は適当なフィルタを使用して補正することができる
。Note that the dispersion of FID (No. 3) caused by applying the gradient magnetic field Gz can be corrected using an appropriate filter.
第１は前記従来のＮＭＲイメージング装置による流体計
測法を説明するためのパルスシーケンス説明図、第２図
は血管のスライス面を表す概念図、第３図は本発明に係
るＮＭＲイメージング装置による流体計測法に使用する
各種パルスのシーケンス図である。
特許出願人 株式会社島津製作所
代理人 弁理士 大 西 孝 治
第１図1 is a pulse sequence explanatory diagram for explaining the fluid measurement method using the conventional NMR imaging device, FIG. 2 is a conceptual diagram showing a slice plane of a blood vessel, and FIG. 3 is a fluid measurement method using the NMR imaging device according to the present invention. FIG. 3 is a sequence diagram of various pulses used in the method. Patent applicant: Shimadzu Corporation Representative: Patent attorney: Takaharu Ohnishi Figure 1
Claims (1)
イス面を決定したあと、傾斜磁場Ｇ×及びＧｙを加えて
位相コーディングを行い、その後ＦＴＤ信号を採取する
流体計測法であって、前記傾斜磁場Ｇｚのある時点にお
いて前記ＦＩＤ信号を採取するよ・うにしたことを特徴
とするＮＭＲイメージング装置による流体計測法。(1) A fluid measurement method in which the slice plane of the flow tube is determined by applying a 90" pulse and a gradient magnetic field Gz, and then phase coding is performed by applying gradient magnetic fields Gx and Gy, and then an FTD signal is collected, A fluid measurement method using an NMR imaging device, characterized in that the FID signal is collected at a certain point in the gradient magnetic field Gz.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58227187A JPS60119417A (en) | 1983-11-30 | 1983-11-30 | Fluid measuring method by nmr imaging device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58227187A JPS60119417A (en) | 1983-11-30 | 1983-11-30 | Fluid measuring method by nmr imaging device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS60119417A true JPS60119417A (en) | 1985-06-26 |
| JPH0527052B2 JPH0527052B2 (en) | 1993-04-20 |
Family
ID=16856849
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP58227187A Granted JPS60119417A (en) | 1983-11-30 | 1983-11-30 | Fluid measuring method by nmr imaging device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS60119417A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS62106321A (en) * | 1985-11-05 | 1987-05-16 | Toshiba Corp | Magnetic resonance imaging apparatus |
| JPH01131649A (en) * | 1987-02-27 | 1989-05-24 | Hitachi Ltd | Mr imaging method and apparatus |
| JPH02291841A (en) * | 1989-04-28 | 1990-12-03 | Shimadzu Corp | Moving body measuring apparatus |
| JPH0318347A (en) * | 1989-06-15 | 1991-01-25 | Hitachi Ltd | Sequence formation of nuclear magnetic resonance imaging device |
| JP2003515119A (en) * | 1999-11-16 | 2003-04-22 | ウォーリン・ベンチャーズ・インコーポレイテッド | Magnetic resonance analysis flowmeter and flow measurement method |
-
1983
- 1983-11-30 JP JP58227187A patent/JPS60119417A/en active Granted
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS62106321A (en) * | 1985-11-05 | 1987-05-16 | Toshiba Corp | Magnetic resonance imaging apparatus |
| JPH0658377B2 (en) * | 1985-11-05 | 1994-08-03 | 株式会社東芝 | Magnetic resonance imager |
| JPH01131649A (en) * | 1987-02-27 | 1989-05-24 | Hitachi Ltd | Mr imaging method and apparatus |
| JPH02291841A (en) * | 1989-04-28 | 1990-12-03 | Shimadzu Corp | Moving body measuring apparatus |
| JPH0318347A (en) * | 1989-06-15 | 1991-01-25 | Hitachi Ltd | Sequence formation of nuclear magnetic resonance imaging device |
| JP2003515119A (en) * | 1999-11-16 | 2003-04-22 | ウォーリン・ベンチャーズ・インコーポレイテッド | Magnetic resonance analysis flowmeter and flow measurement method |
| JP4808885B2 (en) * | 1999-11-16 | 2011-11-02 | ウォーリン・ベンチャーズ・インコーポレイテッド | Magnetic resonance analysis flow meter and flow measurement method |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0527052B2 (en) | 1993-04-20 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP0126381B1 (en) | An nmr method for measuring and imaging fluid flow | |
| EP0171070B1 (en) | Nmr multiple-echo phase-contrast blood flow imaging | |
| EP0233906B1 (en) | Magnetic resonance imaging of high velocity flows | |
| Axel et al. | A time-of-flight method of measuring flow velocity by magnetic resonance imaging | |
| JPH04290953A (en) | Method and device for measuring transfer characteristic of fluid passing through porous medium by nmr image processing | |
| US4520828A (en) | Nuclear magnetic resonance method and apparatus | |
| JPH05184555A (en) | Magnetic resonance imaging method and device therefor | |
| US4836209A (en) | NMR imaging of moving material using variable spatially selected excitation | |
| US4947837A (en) | Method of blood flow imaging | |
| JPH0616766B2 (en) | High-speed flow measurement method using NMR imaging device | |
| JPH03268742A (en) | Imaging device | |
| JPS60119417A (en) | Fluid measuring method by nmr imaging device | |
| US4862080A (en) | Method of deriving a spin resonance signal from a moving fluid, and device for performing this method | |
| US5309099A (en) | Method of determining real-time spatially localized velocity distribution using magnetic resonance measurements | |
| JPH0399632A (en) | Magnetic resonance imaging apparatus | |
| JP3452400B2 (en) | Magnetic resonance imaging equipment | |
| EP0106472B1 (en) | Nuclear magnetic resonance method and apparatus | |
| JPH01502161A (en) | A method for displaying moving parts within the body through measurements using nuclear magnetic resonance | |
| US4991586A (en) | Method for monitoring vascular flow using magnetic resonance signals | |
| GB2127155A (en) | Flow determination by nuclear magnetic resonance | |
| JPS62105013A (en) | Liquid measuring method by nmr imaging device | |
| JPS5983041A (en) | Inspecting method and apparatus utilizing nuclear magnetic resonance | |
| EP2511726A1 (en) | A method and system for determining the flip angle in the transient phase of a gradient echo pulse sequence | |
| JP3366390B2 (en) | MRI equipment | |
| JPH0622934A (en) | Magnetic resonance imaging device and method |