JP4497611B2 - Ultrasonic diagnostic equipment - Google Patents

Description

に基づき、時間のファクタに差分情報ｄｉを反映させたサウンドＳ（ｔ）を生成する手法である。つまり、差分情報ｄｉの値が大きくなるほど、基準サウンドＢ（ｔ）のピッチ（周波数）が大きく又は小さくなる。
【００７４】
一方、第３の生成モードは、複数の差分情報の値ｄｉ１，ｄｉ２，…，ｄｉｎに適したモードである。このモードによれば、上記第１又は第２の生成モードに拠る演算が行なわれ、その結果生成されたサウンドＳ（ｔ）を微小時間毎に繋げて全体として１つのサウンドが生成される。例えば、ｄｉ１，ｄｉ２，…，ｄｉ６の差分値の夫々について、
【数３】

の演算を行なう。そして、Ｓ１〜Ｓ６のサウンドを例えば２００ｍｓｅｃ毎に繋げて合計１２００ｍｓｅｃのサウンドを生成する。
【００７５】
このように何れかの生成モードで生成されたサウンドＳのデータはスピーカ３１に送られ、差分情報に反応した短めのサウンドが発生される。
【００７６】
本実施形態の作用効果を説明する。
【００７７】
いま、微小気泡を主成分とする超音波造影剤を持続投与しながら、例えば心臓筋肉に流入する造影剤、すなわち組織血流のパフュージョンを、マルチショット法を用いたフラッシュエコーイメージング法で観察しているとする。
【００７８】
この場合、図２に示す如く、休止時間Ｔｉの後、複数フレーム分の超音波送受信が連続的に行なわれ、間歇送信に拠る複数枚の画像のデータに得られる。この画像はＢモード像又はＣＦＭ像として表示器２７に表示される。
【００７９】
このとき、マルチショット法で得られる複数フレームの画像には、造影剤を成す微小気泡の消失程度が輝度（信号強度）として反映されている。
【００８０】
例えば、第１フレームの画像では微小気泡由来の高い輝度のエコー信号が観察されるが、第２フレームではこのエコー信号が消失してしまうことがある。また、微小気泡が比較的に壊れ易かったり、投与濃度が低い場合には、第１フレームの画像で殆どの微小気泡は消失し、その後の第２フレームと第３フレームの画像の輝度状態が殆ど変わらないという状態もあり得る。反対に、微小気泡が比較的強靭な場合、第１フレームでは微小気泡は全て消失せずに残り、第２フレーム以降のフレームにおいて、フレームが進むにつれて、徐々に輝度が低下することもあり得る。当然に、送信音圧や造影剤濃度によって、上記の中間的な状態もとり得る。
【００８１】
かかる状況において、本実施形態では、スキャン中に、微小気泡の消失程度を反映させた情報として、フレーム間の信号強度の差分情報が差分検出回路２９から得られる。この差分値の数は演算モードに応じて変わる。この差分情報は、サウンドプロセッサ３０によってサウンドデータに変換され、次いでスピーカ３１からサウンドとして発生される。
【００８２】
差分情報は、フレーム、すなわち時間が進んだときの微小気泡の消失程度を表しているので、スピーカ３１から発生するサウンド（音）は、気泡消失の大小の状態を体感できる情報としてオペレータに伝わる。例えば、第１の生成モードで差分情報ｄｉが生成された場合、気泡消失の程度が大きいほど、操作者には大きなサウンドが聞こえる。
【００８３】
したがって、現在の送信条件が最適なものであるか否かは、操作者がサウンドの強弱、音色などに応じてその場で直感的に（感覚的に）判断できる。なお、どの程度の強弱、音色などのサウンドが聞こえたときに、最も高輝度なエコー信号が造影剤から得られる状態（最適状態）であるかの判断は、若干の訓練を通じて、予め知っておくことが望ましい。
【００８４】
かかる直感的判断により、操作者はその場で、送信音圧を上下させるなど、送信条件を最適状態にしてそのまま診断用のスキャンに移行できる。例えば、造影剤を持続投与していると、その染影効果は１０分程度、持続するので、投与後の僅かな時間帯に、上述したサウンドに拠る送信条件の最適化を終え、そのまま引き続いて本スキャンに移行できる。
【００８５】
これにより、個々の被検体の個体差、投与した造影剤濃度等を加味した最適な送信条件が短時間にその場でリアルタイムに設定できるので、投与した造影剤に対して最も高輝度な信号が得られる最適条件で撮像ができる。
【００８６】
このため、従来のように、一度撮像した画像データを後から読み出す必要も無いので、撮像及び診断が短時間で、かつ容易に行える。
【００８７】
また、得られる画像に関しては、血流と組織との目視識別が容易になるなど、最初から高い診断能の画像が得られるので、再撮像の必要性も格段に減り、その分、操作者の負担や労力が減少し、患者スループットも向上する。
【００８８】
さらに、微小気泡の消失の状態を認識するために、スキャンしながら複数フレームの画像を同時に表示して比較観察するといった、複雑で操作者に負担の多い作業が不要になる。本実施形態のようにサウンドを使用すると、そのサウンドの特質の判断さえ習得しておけばよく、両手をスキャン操作に使いながら複数画面を目視しなければならないこともなく、操作に必要な熟練度も大幅に緩和され、診断に伴う労力が大きく減少し、かつ作業効率も良くなる。操作者の負担が減るので、観察時の異常部位の見落とし等が発生する率も低下し、診断に対する信頼性確保の面でも有効である。
【００８９】
なお、上記第１の実施形態では、微小気泡の消失現象を効果的に認識する手法をフラッシュエコーイメージングに適用する例で説明したが、通常のスキャン法においても本手法を実施することができる。
【００９０】
例えば、通常の連続的送信法の場合に、造影剤が充満した肝臓などの臓器実質に対してスキャン断面を少しずつ変更していくと、スキャンした断面の微小気泡は消失するが、スキャン断面が未消失の新たな断面に次々に移行していくので、その新しい断面で気泡消失現象が次々と起こる。このようなイメージングのときに、操作者がプローブを手動操作してスキャン断面を移動させるときの移動速度が不均一であると、消失の度合いも変わる。このため、撮像された複数の画像に染影度の違いが発生し、診断に影響することがある。
【００９１】
本発明は、このようなスキャン状態に因る不都合をも解消することができる。
すなわち、本発明をかかる通常の連続的送信に拠るスキャンに適用することで、次々に消失する断面の気泡の度合いが一定であれば、発生する音も殆ど一定の大きさになる。この音という、操作者にとって直感的な情報は、画像取得後にその画像を見直して吟味する場合よりも、その場で簡単に気泡消失の程度を把握して、送信音圧を上下させるなどの必要な措置をタイムリーに行なうことができる。
【００９２】
また、本発明に係る実施形態の変形例として、第１の実施形態の超音波診断装置にデモンストレーション用のサウンドを発生させる機能を付加することができる。このデモ用サウンドは、上述した適宜な差分情報ｄｉ（＞０）に対応するサウンドである。例えば、図１に示す如く、操作パネル１３にデモ提示用ボタン１３Ｅを装備し、このボタン１３Ｅからの操作情報を制御回路３２を介してサウンドプロセッサ３０が受けるように構成し、サウンドプロセッサ３０がスピーカ３１を介してデモ用サウンドを発生させればよい。勿論、制御回路３２が直接にスピーカ３１の動作を制御してもよい。
【００９３】
このため、診断前にオペレータがこのボタン１３Ｅを押すと、サウンドを事前に聞くことができる。したがって、診断に入ってから聞くことになるサウンド感を事前に確認又は養うことができる。加えて、デモ用サウンドの強弱、音色などを適宜に変化させるように構成しておくことで、オペレータは診断前に超音波造影剤の消失状態の変化幅を音を通して感覚的に確認しておくことができ、診断に移行した後の操作をより迅速に且つ的確に行なうことが可能になる。
【００９４】
（第２の実施形態）
本発明の第２の実施形態に係る超音波診断装置を図５に基づき説明する。
【００９５】
この超音波診断装置は、前述した第１の実施形態の超音波診断装置と同等の機能を有するが、相違する点は、図５に示す如く、差分検出回路２９への信号取り出し位置にある。すなわち、図１の装置構成に比べて、差分検出回路２９の入力端を超音波受信ユニット２２の出力段、すなわちレシーバユニット２３の前段に置いている。その他の構成は図１のものと同一又は同等である。
【００９６】
これにより、差分検出回路２９は、単に受信遅延加算されただけのＲＦ信号の状態のエコー信号を入力する。つまり、差分検出回路２９はこのＲＦ信号を使って前述した各種の演算モードの差分演算を行なう。この差分演算により、エコー信号の位相乱れ等の情報が得られる。この情報は微小気泡のサイズ変化、振動など、消失現象以外のランダムな挙動を反映したものとなる。そこで、この情報に基づいてサウンドプロセッサ３０が前述と同様に動作し、音信号がスピーカ３１から出力される。
【００９７】
本実施形態によれば、差分検出回路はエコー信号をＲＦ信号として記憶する必要があるため、記憶に必要なデータ量は多くなるものの、ＲＦ信号の状態で検出することから、音圧に対して敏感な微小気泡の検出能が良くなり、微小気泡の消失の程度をより精度良く反映させた音を聞くことができる。
【００９８】
（第３の実施形態）
本発明の第３の実施形態に係る超音波診断装置を図６，７に基づき説明する。
【００９９】
この超音波診断装置は、差分によって得た微小気泡の消失具合の情報を出力する仕方に特徴を有する。
【０１００】
この装置は、前述した第１の実施形態のそれとと比べて、サウンドプロセッサをインジケータ生成回路３５に置き換え、この生成回路３５の出力先をデータ合成器２６としている。
【０１０１】
インバータ生成回路３５は、差分検出回路２９により検出されたスカラ量に変換された輝度差ｄｉの情報を入力し、この情報を対応する数値又はレベルメータ情報に変換する。この変換情報はデータ合成器２６を介して表示器２７に表示される。図７（Ａ），（Ｂ）には、レベルメータ形式で表示される２つの例を示す。このレベルメータ形式は日常良く目にするものであるから、操作者は、これを見て、微小気泡の消失状態を直感的に把握することができる。
【０１０２】
なお、表示器２７には、マルチショット法を用いたフラッシュエコー法で得られた第１フレーム画像と第Ｎフレーム画像とを並べて表示し、輝度差を目視で判別するようにしてもよいが、本実施形態のようにスカラ量ｄｉを表示することで、より定量的な値を直感的に知らせることができる。このスカラ量の表示の場合、診断画像としては、最も高輝度であることが多い第１フレームの画像のみを表示すれば足りる。
【０１０３】
上述した各実施形態は単なる例示であって、本発明の範囲を限定することを意図するものではない。本発明の範囲は特許請求の範囲の記載にしたがって決まるもので、本発明の範囲を逸脱しない範囲において様々な態様のものを実施することができる。
【０１０４】
【発明の効果】
以上説明したように、本願発明に係る超音波診断装置によれば、微小気泡を主成分とする超音波造影剤を被検体に投与して行なうコントラストエコー法において、微小気泡の消失の程度を音などの体感情報に変化させて出力するので、操作者は造影剤が関心領域に流入していることを直感的に知ることができる。
【０１０５】
また、操作者は、かかる微小気泡の消失の程度を、連続したフレーム画像を見なくても、スキャン時において、感覚的に認識（判別）することができる。そこで、例えば、操作者は、大きい音（周波数が高い音）ならば、気泡消失の程度が大き過ぎると直感的に判断して送信パルスの出力を下げ、反対に、小さい音ならば、気泡消失の程度が小さ過ぎると直感的に判断して送信パルスの出力を上げる。この操作をその場でリアルタイムに繰り返すことができ、これにより、気泡消失と画質のバランスをとり、最終的に最適な送信音圧に設定することができる。
【０１０６】
したがって、従来のように撮像後に画像を読み出して相互比較して微小気泡の消失の程度を読み出す必要が無く、スキャン時にその場でタイムリーに、音などに応じて必要な措置を講じることができる。このため、１回の撮像で済むので、再撮像の必要性も格段に小さくなり、操作の手間も減少し、操作時間や撮像時間も節約できる。また、関心領域の血流・組織の判別は勿論、送信条件の設定にも適用でき、汎用性も高い。
【０１０７】
加えて、スキャン中に複数のモニタ画像を黙視で相互に比較する必要もないので、操作が簡単になってその労力が少なくなり、要求される熟練度も格段に低くて済み、さらに診断に対する信頼性も高くなる。
【０１０８】
これにより、血管部の血流動態の情報やパフュージョンの検出による臓器実質レベルの血行動態の情報をより高精度且つ高精細に定量化するできる。この結果、血流情報の定量化、鑑別診断に詳細な情報を確実に提供することができる。
【図面の簡単な説明】
【図１】本発明の第１の実施形態に係る超音波診断装置のブロック図。
【図２】マルチショット法を用いたフラッシュエコーイメージングの超音波送受信のタイミングを説明する図。
【図３】エコー信号に対する種々の差分演算のモード（第１〜第３の演算モード）を説明する図。
【図４】エコー信号に対する種々の差分演算のモード（第１〜第３の演算モード）を説明する図。
【図５】本発明の第２の実施形態に係る超音波診断装置のブロック図。
【図６】本発明の第６の実施形態に係る超音波診断装置のブロック図。
【図７】微小気泡の消失状態をレベルメータ方式で表すときの表示の説明図。
【符号の説明】
１１ 装置本体
１２ 超音波プローブ（送受信手段）
１３ 操作パネル
１４ ＥＣＧセンサ
２１ 送信ユニット（送受信手段）
２２ 受信ユニット（送受信手段）
２３ レシーバユニット（送受信手段）
２４ ＢモードＤＳＣ
２５ ドプラユニット
２６ データ合成器
２７ 表示器
２８ イメージメモリ
２９ 差分検出回路（取得手段）
３０ サウンドプロセッサ（伝達手段・生成手段）
３１ スピーカ（伝達手段・出力手段）
３２ 制御回路（送信制御手段を含む。取得手段及び伝達手段の一部を成す。）
３３ データ発生回路
３４ 心拍検出ユニット
３５ インジータ生成回路（伝達手段・生成手段）[0001]
BACKGROUND OF THE INVENTION
The present invention belongs to the field of ultrasonic imaging in which an ultrasonic contrast agent mainly composed of microbubbles is administered to a subject and imaging is performed based on the contrast echo method. Specifically, the state of disappearance of the microbubbles is described. Adopted a new method for monitoring Super Sonic diagnostic equipment In place Related. The present invention is particularly suitable when a flash echo imaging (FEI) method, which is a form of contrast echo method, is performed.
[0002]
[Prior art]
Medical applications of ultrasonic signals cover various fields, and an ultrasonic diagnostic apparatus is one of them. An ultrasonic diagnostic apparatus is an apparatus that obtains an image signal by transmitting and receiving an ultrasonic signal, and is used in various modes by utilizing the noninvasive nature of the ultrasonic signal.
[0003]
The mainstream of this ultrasonic diagnostic apparatus is a type that obtains a tomographic image of a soft tissue of a living body using an ultrasonic pulse reflection method. This imaging method can obtain a tomographic image of a tissue non-invasively and can be displayed in real time compared to other medical modalities such as X-ray diagnostic equipment, X-ray CT scanner, MRI equipment, and nuclear medicine diagnostic equipment. The apparatus is small and relatively inexpensive, has no exposure to X-rays, and has many advantages such as blood flow imaging based on an ultrasonic Doppler method. For this reason, it is widely used in the diagnosis of the heart, abdomen, mammary gland, urology, and gynecology. In particular, by simply operating the ultrasound probe on the body surface, heart beats and fetal movements can be observed in real time, and since there is no exposure, the test can be repeated many times. It has various advantages that it can be easily inspected.
[0004]
In the field of this ultrasonic diagnostic apparatus, recently, when performing an examination of the heart, abdominal organs, etc., a contrast echo method that injects an ultrasonic contrast agent from a vein and evaluates blood flow dynamics has attracted attention. . The method of injecting a contrast medium from a vein is less invasive than the method of injecting from a artery, and diagnosis by this evaluation method is becoming widespread.
The main components of the ultrasound contrast agent are microbubbles (microbubbles), which serve as a reflection source for reflecting ultrasound signals. The higher the injection amount and concentration of the contrast agent, the greater the contrast effect. However, due to the nature of the bubbles in the contrast agent, the contrast effect time may be shortened depending on the state of ultrasonic irradiation. In view of such a situation, a persistent and pressure-resistant contrast medium has been developed in recent years, but there is a concern that the long-term stay of the contrast medium in the body leads to an increase in invasiveness.
[0005]
When this contrast echo method is performed, contrast agents are successively supplied to the region of interest of the subject site by blood flow. For this reason, even if an ultrasonic wave is irradiated and the bubble disappears once, it is assumed that the contrast effect is maintained if a new bubble flows into the region of interest at the time of the next ultrasonic irradiation. However, in practice, ultrasonic transmission / reception is usually performed thousands of times per second, and considering the fact that there are organs with slow blood flow velocity and blood flow dynamics of relatively thin blood vessels. On the diagnostic image, bubbles disappear one after another before confirming the luminance enhancement by the contrast agent, and the contrast effect is instantly attenuated.
[0006]
Among the diagnostic methods using a contrast agent, the most basic diagnostic method is to know the presence or absence of blood flow at the diagnostic site by examining the presence or absence of luminance enhancement due to the contrast agent. More advanced diagnostic methods include knowing the temporal change in the spatial distribution of the contrast agent from the extent of the brightness change at the diagnostic site and the degree of brightness enhancement, the time from the injection of the contrast agent to the region of interest, In addition, this is a technique for obtaining a change in echo luminance with time (Time Intensity Curve: TIC) or a maximum luminance due to a contrast agent in the ROI.
[0007]
This contrast echo method can also be effectively carried out by using a harmonic imaging method that forms an image using a non-fundamental wave component of an ultrasonic echo signal. The harmonic imaging method is an imaging method that separates and detects only non-fundamental wave components due to nonlinear behavior that occurs when microbubbles that are main components of a contrast agent are ultrasonically excited. Since biological organs are relatively difficult to cause nonlinear behavior, a contrast agent image with a good contrast ratio can be obtained by this harmonic imaging method.
[0008]
Furthermore, an imaging technique called a flash echo imaging method (or also called a transient response imaging method) has been proposed by utilizing the phenomenon that microbubbles disappear due to ultrasonic irradiation as described above. It has been reported that this can improve brightness enhancement (for example, the literature “67-95 Study of Flash Echo Imaging (1), Naohisa Kamiyama et al., 67th Annual Meeting of the Japanese Society of Ultrasonic Medicine, 1996 June, "or JP-A-8-280674). In principle, this imaging method is to transmit intermittently at a rate of 1 frame per several seconds instead of the conventional continuous scan of several tens of frames per second. This is a method of trying to obtain a high echo signal by erasing the microbubbles densely packed together at once.
[0009]
Further, Japanese Patent Laid-Open No. 8-280674 proposes an imaging method called a multi-shot method. According to this multi-shot method, after microbubbles are concentrated based on the intermittent transmission method, ultrasonic transmission and reception for a plurality of frames is sequentially executed. When observing this multiple frame image, the first frame image exhibits high brightness due to a high echo signal, and the subsequent second frame and subsequent images are collected while the microbubbles disappear, so the signal value gradually decreases. Observed. Therefore, the change in the image value over a plurality of frames indicates the degree of disappearance of microbubbles on the scan surface caused by ultrasonic irradiation as a result.
[0010]
The first advantage of the multi-shot method is that a luminance difference (signal difference) between images of a plurality of frames can be used. A harmonic image is generated by mixing a harmonic signal derived from an ultrasound contrast agent and a so-called tissue harmonic signal caused by tissue nonlinearity. Depending on the subject, the intensity of the tissue harmonic signal component may be relatively high. In such a case, it becomes impossible to determine whether the luminance (signal value) of the image is really due to the contrast agent, and reliability There may be concerns about detection of hemodynamics at this point. On the other hand, according to the images of multiple frames collected by the multi-shot method, the brightness of the microbubble (blood flow) signal decreases as the number of frames increases. The presence of bubbles can be easily confirmed, and such a determination can be made reliably.
[0011]
The second advantage of the multi-shot method is the setting of the optimum transmission sound pressure. When performing the contrast echo method, it is important to determine the transmission sound pressure of the apparatus at an optimum level. If the transmission sound pressure is too low, the above-described high-intensity flash echo signal cannot be detected. On the other hand, if the transmission sound pressure is too high, microbubbles disappear more than necessary, and the dyeing effect is reduced. The optimum transmitted sound pressure level tends to differ for each type of ultrasound contrast agent, and a clear value has not yet been elucidated. On the other hand, it is very difficult to specify an optimal transmission sound pressure level before diagnosis because the attenuation constant for the ultrasonic signal of the subject has individual differences. In such various situations, if the multi-shot method is used, it is possible to observe the disappearance of microbubbles by changing the brightness of the image of multiple frames. Therefore, the transmission sound pressure level is adjusted based on the disappearance and the optimum value is specified. Is possible.
[0012]
When the multi-shot echo method is used in this way, information regarding disappearance of microbubbles can be obtained by comparing the images of a plurality of frames that are continuously captured with each other, and can be used effectively in various situations.
[0013]
[Problems to be solved by the invention]
In the case of the conventional multi-shot method, it is necessary to compare and observe images of a plurality of frames in order to effectively use the imaging method. This comparative observation must be performed by recalling the image recorded during the diagnosis either after the diagnosis is stopped or after the diagnosis.
This is because the operator needs to be aware of various other things related to diagnosis during diagnosis.
[0014]
However, in the case of this mid-calling or post-calling, it cannot be applied to the optimal setting of the real-time transmission sound pressure, and it is enough to determine whether the region of interest in the captured image is a bloodstream or a tissue. Limited to use.
[0015]
In addition, since it is not a real-time diagnosis, even if it is desired to re-image during diagnosis or if it is desired to take an image from a different angle, it cannot be performed on the spot, so a new re-scan must be performed.
[0016]
Therefore, as another method of the comparative observation, it is technically possible to display images of a plurality of frames simultaneously with scanning at the time of imaging and perform diagnosis in real time while performing comparative observation.
[0017]
However, in the case of this real-time diagnosis, the operator must hold the probe with one hand while comparatively observing, for example, three frames of images, and also operate the console with the other hand. For this reason, very skill is required for operation, and operability is not good. Further, the operator needs to observe and interpret the region of interest while comparing the images of a plurality of frames with each other, and the labor involved in the diagnosis becomes very large. Moreover, due to such a large amount of labor, the rate of occurrence of oversight or the like is high, and it cannot be said that the reliability for diagnosis is sufficient.
[0018]
From a general point of view, image diagnosis is a situation where it is desired to reduce the visual burden as much as possible, as it makes a qualitative diagnosis from the contrast pattern of the organ or the observation of the running state of blood vessels. .
[0019]
One object of the present invention is to obtain information on the extent of disappearance of microbubbles in real time on the spot that is actually diagnosed in an intuitive (sensory) manner, and to make effective use of this information. Ultrasonic diagnostic equipment that can perform ultrasonic diagnostics Place Is to provide.
[0020]
Another object of the present invention is to provide an ultrasonic diagnostic apparatus in which the operator's operation burden and labor are small and the skill level required for the operation is low when performing the contrast echo method. Place Is to provide.
[0021]
Furthermore, another object of the present invention is to obtain information on the degree of disappearance of microbubbles in real time on the spot where the diagnosis is actually carried out when performing the contrast echo method, and has a high diagnostic ability based on this information. An ultrasonic diagnostic apparatus that can obtain an image and perform reliable scan preparation based on the information, requires less burden on the operator and labor, and requires less skill in operation. Place Is to provide.
[0022]
[Means for Solving the Problems]
In order to achieve the various objects described above, according to one aspect of the ultrasonic diagnostic apparatus of the present invention, an ultrasonic pulse signal is transmitted to a subject administered with an ultrasonic contrast agent mainly composed of microbubbles. And transmitting / receiving means for receiving an echo signal generated from the subject along with the transmission, acquisition means for obtaining data other than an image representing the degree of disappearance of the ultrasound contrast agent from the echo signal, and the data And transmission means for transmitting the information as experience information to the operator.
[0023]
For this reason, the operator can obtain the degree of disappearance of the ultrasonic contrast agent as sensible information (sensory information) such as sound in real time at the scanning site. For this reason, the operator needs to change the transmission conditions on the spot while scanning by knowing in advance what level of disappearance is when the sensory information exhibits such a state. Measures can be taken in a timely manner. Therefore, the situation where rescanning has to be performed is remarkably reduced, so that the labor and labor of the operator is reduced, and the entire imaging time can be reduced. On the other hand, complicated operations such as observing multiple monitor screens silently and comparing each other during scanning are unnecessary, and the disappearance state of the contrast agent is intuitively (sensory) according to sensory information such as sound. It is possible to make a decision and to take measures such as adjusting the transmission conditions. Thereby, the operation is simple and the degree of skill required for the operation is low.
[0024]
The basic configuration described above can be further expanded into the following various aspects.
[0025]
Preferably, the transmission / reception means instructs transmission of the ultrasonic pulse signal every time a transmission stop period elapses, and at the time of transmission, transmission control means for sequentially transmitting the ultrasonic pulses in order to obtain an image of a plurality of frames. Have
[0026]
Preferably, the acquisition unit is a unit that obtains a signal intensity difference between frames from the echo signals for the plurality of frames as data representing a degree of disappearance of the ultrasound contrast agent.
[0027]
At this time, for example, the acquisition unit calculates a difference between the signal strengths of the frames as a signal strength difference between the frames, and within a region of interest set in a part of the image of each frame. It is a means for calculating a difference in the sum of signal intensities, or a means for calculating a difference in the sum of signal intensities on a scanning line set for each frame.
[0028]
The acquisition means may be a means for calculating a plurality of signal intensity differences between arbitrary frames as signal intensity differences between the frames. At this time, as an example, the acquisition means calculates the signal intensity difference by sequentially changing the combination between adjacent frames as the plurality of signal intensity differences, or the image of each frame in the depth direction. It is means for calculating a signal intensity difference for each region divided into a plurality of regions.
[0029]
Furthermore, according to a preferred aspect, in each configuration described above, the sensation information is sound information. In this case, the transmission means includes generation means for generating data representing the degree of disappearance of the ultrasound contrast agent in the sound information data, and output means for outputting the sound information data as sound. desirable. As an example, the generation means is means for generating data of the sound information by reflecting data representing the degree of disappearance of the ultrasonic contrast agent in the term of amplitude or time of a reference sound waveform.
[0030]
Further, according to a preferred aspect, the bodily sensation information may be visual information displayed in a graphic form.
[0031]
Furthermore, you may provide the demonstration means which generates the information for demonstration regarding the said bodily sensation information. If this demonstration means is used, the operator can listen to sensation information such as sound in advance as a demonstration sound before diagnosis. Therefore, it is possible to confirm or nurture the sense of sound, thereby contributing to a quicker and more accurate operation during diagnosis.
[0032]
According to another aspect, the ultrasonic diagnostic apparatus of the present invention is an apparatus for diagnosing a subject to which an ultrasonic contrast agent mainly composed of microbubbles is administered, and an ultrasonic pulse is transmitted to the subject via a probe. A transmission unit that transmits a signal, a reception unit that receives an echo signal generated from the subject accompanying the transmission through the probe and delay-adds the echo signal, and an echo that is delayed and added by the reception unit A receiver for detecting a signal; a difference detection circuit for detecting a signal difference between frame images from an output signal of the receiving unit or the receiver; and a sound processor for converting the signal difference detected by the difference detection circuit into sound data; And a speaker for outputting sound data converted by the sound processor as sound. This also exhibits the same operational effects as the above-described apparatus.
[0035]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0036]
(First embodiment)
A first embodiment will be described with reference to FIGS. The ultrasonic diagnostic apparatus according to this embodiment can be applied to all regions of interest when an ultrasonic contrast agent is administered to a subject and the blood flow state is observed from the degree of staining thereof. An ultrasound diagnostic apparatus having a function of identifying blood flow data based on the degree of staining of a contrast medium (perfusion) flowing into muscle and identifying an abnormal site will be described.
[0037]
FIG. 1 schematically shows the overall configuration of the ultrasonic diagnostic layer apparatus according to the first embodiment.
The ultrasonic diagnostic apparatus shown in FIG. 1 includes an apparatus main body 11, an ultrasonic probe 12, an operation panel 13, and an ECG (electrocardiograph) 14 connected to the apparatus main body 11.
[0038]
The operation panel 13 includes or can be connected to a keyboard 13A, a trackball 13B, a mouse 13C, and an operation panel circuit 13D. These operation devices are used for an operator to input or set patient information, apparatus conditions, ROI (region of interest), etc. as in the conventional apparatus, and to change various setting conditions according to the present invention. used.
[0039]
The ultrasonic probe 12 is a device responsible for transmission / reception of an ultrasonic signal to / from a subject, and includes a piezoelectric vibrator such as a piezoelectric ceramic as an electrical / mechanical reversible conversion element. As a preferred example, a plurality of piezoelectric vibrators are arranged in an array and are provided at the probe tip to constitute a phased array type probe 12. As a result, the probe 12 converts the pulse drive voltage applied from the apparatus body 11 into an ultrasonic pulse signal and transmits it in a desired direction within the subject, while corresponding to the ultrasonic echo signal reflected by the subject. It converts to an echo signal of the voltage to be.
[0040]
The ECG 14 is mainly used in contact with the body surface of the subject, and obtains an ECG (electrocardiographic waveform) signal associated with the heartbeat of the subject.
[0041]
In the present embodiment, the apparatus main body 11 can instruct switching between “B mode” and “CFM (Color Flow Mapping) mode” as an imaging mode.
[0042]
Specifically, the apparatus main body 11 includes a transmission unit 21 and a reception unit 22 connected to the probe 12, a receiver unit 23 placed on the output side of the reception unit 22, and a B-mode DSC (digital scan converter). 24, a Doppler unit 25, a data synthesizer 26, a display 27, and an image memory 28.
[0043]
Further, the apparatus main body 11 responds to an instruction from the control circuit 32, a difference detection circuit 29 provided in order at the output stage of the receiver unit 23, a sound processor 30, a speaker 31, a control circuit 32 that receives an operation signal from the operation panel 13. And a data generation circuit 33 that operates as well as a heartbeat detection unit 34 that receives an ECG (electrocardiogram) signal from the ECG 14.
[0044]
Among these, the control circuit 32, the difference detection circuit 29, the sound processor 30, and the speaker 31 are main elements that realize the features of the present invention, and their operations will be described later.
[0045]
The control circuit 32 has a computer configuration including a CPU and a memory, and controls the operation of the entire apparatus according to a preprogrammed procedure. This control operation includes transmission control for the transmission unit 21 (transmission timing, transmission delay, etc.), reception control for the reception unit 22 (reception delay, etc.), a display data generation instruction for the data generator 33, and timing control for other elements. Etc.
[0046]
Of these, the transmission control also includes the implementation of a transmission timing control method that characterizes the present invention. That is, this transmission timing is controlled by the flash echo imaging (FEI) method based on the intermittent transmission method using the multi-shot method.
The concept of this transmission timing is shown in FIG.
[0047]
In the figure, the scan (transmission / reception) timing for one frame is schematically shown by one black triangle. According to this control, after the scan is suspended for a variable period Ti that can be changed, flash echo imaging based on the intermittent transmission to be scanned is performed. Since ultrasonic transmission is stopped during the rest period Ti, the microbubbles of the contrast agent can be concentrated in the region of interest.
[0048]
In the rest period Ti, for example, a heartbeat timing signal from the heartbeat detection unit 34 is set as a trigger signal. As an example, the rest period Ti is set as a period corresponding to an appropriate heart rate, such as every 1 heartbeat, every 5 heartbeats,.
[0049]
Further, when the heartbeat timing signal is not used, for example, a clock built in the computer of the control circuit 32 is used, for example, every 0.1 seconds, every second,... Every 10 seconds, etc. The rest period Ti may be set.
[0050]
The pause period Ti does not have to be the same value every time, and may be programmed in advance so as to increase by 1 second for each pause from 1 second to 10 seconds, for example.
[0051]
Further, the scanning is based on a multi-shot method in which a plurality of frames (for example, the number of frames N = 3) are continuously scanned with a relatively short period Tf. That is, as shown in FIG. 2, a continuous N-frame ultrasonic image is obtained in synchronization with the trigger signal after suspension of transmission. This period Tf is a time required to generate an image of one frame and is generally expressed as an inverse number of the frame rate Fr (Tf = 1 / Fr). The frame rate Fr is generally a relatively fast repetition frequency of about 10 to 100 Hz (conventionally). The number N of frames can be changed / set to an arbitrary plurality of values via the operation panel 13, for example.
[0052]
Returning to FIG. 1, in response to the display data generation command from the control circuit 32, the data generation circuit 33 generates graphic data or annotation data of the designated ROI (region of interest) and sends it to the data synthesizer 26. send.
[0053]
The ECG 14 obtains an ECG (electrocardiographic waveform) signal and sends it to the heartbeat detection unit 34. The heartbeat detection unit 34 receives the ECG signal from the ECG 14 and sends the waveform data to the data synthesizer 28 for display, while detecting the timing of the pulsation, and this timing signal is used for an electrocardiographic scan. The signal is sent to the control circuit 32 as a signal. Usually, the timing of the R wave in the ECG signal is detected as the timing of this pulsation. However, since the operator can designate an arbitrary delay time from the R wave via the operation panel 13, as a result, an arbitrary heartbeat time phase can be designated.
[0054]
The configuration of the transmission / reception system placed under the control of such a control system is as follows.
[0055]
The transmission unit 21 has a pulse generator, a transmission delay circuit, and a pulser (not shown). The pulse generator generates a rate pulse based on a constant pulse repetition frequency (PRF). This rate pulse is distributed to the number of transmission channels and sent to the transmission delay circuit.
The transmission delay circuit is supplied with a timing signal for determining the delay time from the control circuit 32 for each transmission channel. As a result, the transmission delay circuit gives a command delay time to the rate pulse for each channel. A rate pulse with a delay time is supplied to the pulser for each transmission channel. The pulser gives a voltage pulse to each piezoelectric vibrator (transmission channel) of the probe 12 at the timing of receiving the rate pulse. As a result, an ultrasonic signal is emitted from the probe 12. The ultrasonic signal transmitted from the ultrasonic probe 12 is focused in a beam shape within the subject and set in the scan direction in which the transmission directivity is commanded.
[0056]
The transmitted ultrasonic pulse signal is reflected by a discontinuous surface of acoustic impedance in the subject. This reflected ultrasonic signal is received again by the probe 12 and converted into an echo signal having a corresponding voltage amount. This echo signal is taken from the probe 12 into the reception unit 22 for each reception channel.
[0057]
The receiving unit 22 includes a preamplifier, an A / D converter, a reception delay circuit, and an adder (all not shown) in that order from the input side. Each of the preamplifier, the A / D converter, and the reception delay circuit incorporates a circuit corresponding to the reception channel and is formed in a digital type reception unit. The delay time of the reception delay circuit is given from the control circuit 31 as a signal of a delay time pattern in accordance with the desired reception directivity. For this reason, the echo signal is amplified by a preamplifier for each reception channel, converted to a digital signal by an A / D converter, further given a delay time by a reception delay circuit, and then added to each other by an adder. . By this addition, the reflection component from the direction corresponding to the desired reception directivity is emphasized. By integrating the performance of the transmission directivity and the reception directivity, the overall performance of the transmitted and received ultrasonic beams can be obtained.
[0058]
The output terminal of the adder of the receiving unit 22 reaches the display data combiner 28 via the receiver unit 23 and the B mode DSC 24 in order.
[0059]
Although not shown, the receiver unit 23 includes a logarithmic amplifier, an envelope detector, and the like. In the case of an apparatus that implements the harmonic imaging method, the receiver unit 27 is additionally equipped with a band-pass filter that passes only harmonic components that are, for example, twice the transmission frequency of the ultrasonic pulse signal. . The receiver unit 23 generates echo data in the direction in which reception directivity is given in a digital amount and sends the digital data to the B mode DSC 24.
[0060]
The B mode DSC 24 converts the echo data from the raster signal sequence of the ultrasonic scan into the raster signal sequence of the video format and sends it to the data synthesizer 28.
[0061]
The image memory 28 is connected to the B-mode DSC 24 and includes a memory element for recording a processing signal of the DSC (either or both of a raster signal sequence of an ultrasonic scan and a raster signal sequence of a video format) and a writing / reading control circuit thereof. Prepare. The echo data recorded in this memory element can be read out and used in units of frames during or after the scan (diagnosis). The read data is sent to the display 29 via the B mode DSC 24 and the display data synthesizer 28 and displayed.
[0062]
A Doppler unit 27 is provided on the output side of the receiver unit 23. The Doppler unit 27 receives the added echo signal processed by the receiving unit 22. Although not shown, the unit 27 includes a quadrature detector, a clutter removal filter, a Doppler shift frequency analyzer, an arithmetic unit such as an average speed, a DSC, a color processing circuit, and the like, and a Doppler shift frequency, that is, velocity information of blood flow. And its power information are obtained as color flow mapping data (CFM data). The color flow mapping data is subjected to processing such as noise cancellation by a DSC built in the Doppler unit 27, and its scanning method is converted and sent to the data synthesizer 26. The color flow mapping data can be sent to the image memory 25 for storage.
[0063]
The data synthesizer 28 receives B mode image data (grayscale image) sent from the B mode DSC 24, CFM mode image data (color flow image) sent from the Doppler unit 27, and sent from the heart rate detection unit 32. The ECG waveform data and / or desired setting parameters are reconstructed into one frame of image data by processing such as arranging or overlapping. The frame image data is sequentially read out by the display device 29. In the display 29, the image data is converted into an analog quantity by a built-in D / A converter, and a tomographic image of the tissue shape of the subject is displayed on a display such as a TV monitor.
[0064]
Next, the sub detection circuit 29, the sound processor 30, and the speaker 31 shown in FIG. 1 will be described.
[0065]
The difference detection circuit 29 includes a plurality of frame memories (not shown), write / read circuits thereof, and a calculator for calculating a difference in signal strength. Therefore, the difference detection circuit 29 receives the echo signal sent from the receiver unit 23, temporarily stores it, and stores it in the frame. Then, the difference in signal strength between frames is calculated in an appropriate calculation mode at an appropriate timing.
[0066]
There are various calculation modes, and the calculation mode is designated from the control circuit 32 via the operation panel 13. This calculation mode may be set as a default.
[0067]
First, as the types of calculation modes when the difference is the scalar quantity di, (1): the difference of the sum of the frame signal intensities (first calculation mode), (2): the signal intensity of the region of interest set in the frame Difference (second calculation mode), (3): there is a method of calculating the signal intensity difference of one scanning line designated in the frame (third calculation mode).
[0068]
In the first calculation mode, as schematically shown in FIG. 3A, for example, the signal intensity of each pixel in the first frame and the Nth frame (final frame) is summed, and the difference di between the sum values is calculated. This is a method for obtaining. The frames to be subjected to the difference process may be adjacent frames or frames of any combination. According to the second calculation mode, as schematically shown in FIG. 3B, an ROI (region of interest) is set in advance in a part of the image. The ROI has a shape such as a circle, an ellipse, or a rectangle. Then, for example, the signal intensity (luminance) in the ROI of the first frame and the Nth frame is calculated, and the difference di is calculated. Further, according to the third calculation mode, as schematically shown in FIG. 3C, attention is paid to one (or a plurality of) scanning lines of each frame, and the signal intensity of the pixels on the scanning lines is calculated. . Then, the signal intensity difference di is calculated between frames.
[0069]
The difference detection circuit 29 can also obtain a plurality of signal intensity differences di1, di2,. One calculation method (fourth calculation mode) is a method of taking a difference between adjacent frames with respect to echo signals of a plurality of continuous frames N obtained by each multi-shot method. For example, the signal strength difference between the first frame and the second frame is di1, the second frame and the third frame are di2,..., And the n−1 and nth frames are di (n−1). ). However, this fourth calculation mode is carried out in combination with any of the first to third calculation modes described above (of course, the combination may be set in advance). FIG. 4A schematically shows a concept when the difference calculation is performed in the fourth calculation mode based on the first calculation mode.
[0070]
Further, another calculation method (fifth calculation mode) for obtaining a plurality of signal intensity differences is, for example, between the first frame and the Nth frame, as shown in FIG. This is a method for targeting the divided area. For example, the signal intensity difference calculated by paying attention to the depth region of 0 to 1 cm from the body surface is calculated by paying attention to the depth region of di1, 1 to 2 cm, and di2, ..., n to n + 1 cm. Let the computed value be din.
[0071]
The difference information di or di1, di2,..., Din thus obtained is sent to the sound processor 30. The sound processor 30 generates a sound signal based on a predetermined generation mode using the input difference information. In the present embodiment, the following three modes are prepared as the generation mode, and the control circuit 32 is configured to designate a desired generation mode to the sound processor 30 in response to an operator command. Of course, the generation mode of the sound processor 30 may be fixed in advance.
[0072]
The first generation mode is a mode when the value of the difference information di is one, and uses the reference sound waveform “B (t): t = time”. That is, if the generated sound is S (t),
[Expression 1]
S (t) = di · B (t)
A sound S (t) reflecting the difference information di is generated based on the equation (1). This reference waveform B (t) may be arbitrary. As an example, it is convenient for the waveform signal to be about 1 second at a long time. For example, a so-called beep sound currently used in a personal computer (a warning sound such as “Pooh, Pooh”, a fall such as “Pyon”, “Pawn”). Sound, plosive, etc.) are preferred. The first generation mode is a method that requires the simplest calculation, and a sound S (t) whose amplitude is proportional to the difference information di can be obtained.
[0073]
The second generation mode is a mode when the value of the difference information di is one.
[Expression 2]

Is a method of generating a sound S (t) in which the difference information di is reflected in the time factor. That is, as the value of the difference information di increases, the pitch (frequency) of the reference sound B (t) increases or decreases.
[0074]
On the other hand, the third generation mode is a mode suitable for a plurality of difference information values di1, di2,. According to this mode, an operation based on the first or second generation mode is performed, and the sound S (t) generated as a result is connected every minute time to generate one sound as a whole. For example, for each of the difference values of di1, di2,.
[Equation 3]

Perform the operation. And the sound of S1-S6 is connected every 200 msec, for example, and the sound of a total of 1200 msec is produced | generated.
[0075]
Thus, the data of the sound S generated in any one of the generation modes is sent to the speaker 31, and a short sound that reacts to the difference information is generated.
[0076]
The effect of this embodiment is demonstrated.
[0077]
Now, while continuously administering an ultrasound contrast agent mainly composed of microbubbles, for example, contrast agent flowing into the heart muscle, that is, perfusion of tissue blood flow, is observed by flash echo imaging using the multi-shot method. Suppose that
[0078]
In this case, as shown in FIG. 2, after a pause time Ti, ultrasonic transmission / reception for a plurality of frames is continuously performed, and data of a plurality of images based on intermittent transmission is obtained. This image is displayed on the display 27 as a B-mode image or a CFM image.
[0079]
At this time, in the images of a plurality of frames obtained by the multi-shot method, the disappearance degree of the microbubbles forming the contrast agent is reflected as luminance (signal intensity).
[0080]
For example, a high-intensity echo signal derived from microbubbles is observed in the first frame image, but this echo signal may disappear in the second frame. In addition, when the microbubbles are relatively fragile or when the administration concentration is low, most of the microbubbles disappear in the first frame image, and the luminance state of the subsequent second and third frame images is almost the same. There may be a situation where it does not change. On the other hand, when the microbubbles are relatively strong, all the microbubbles remain without disappearing in the first frame, and in the second and subsequent frames, the luminance may gradually decrease as the frame progresses. Naturally, the above intermediate state can be taken depending on the transmission sound pressure and the contrast agent concentration.
[0081]
In this situation, in this embodiment, difference information on the signal strength between frames is obtained from the difference detection circuit 29 as information reflecting the disappearance degree of the microbubbles during scanning. The number of difference values varies depending on the calculation mode. This difference information is converted into sound data by the sound processor 30 and then generated as sound from the speaker 31.
[0082]
Since the difference information represents the degree of disappearance of the minute bubbles when the frame, that is, the time advances, the sound (sound) generated from the speaker 31 is transmitted to the operator as information that allows the user to experience the state of the disappearance of the bubbles. For example, when the difference information di is generated in the first generation mode, the operator can hear a louder sound as the degree of bubble disappearance is larger.
[0083]
Therefore, the operator can intuitively (sensually) determine whether or not the current transmission condition is optimal according to the strength of the sound, the tone color, and the like. It should be noted that the degree of strength, tone, and other sounds that can be obtained from the contrast agent when the sound of the highest intensity is heard (optimum state) is known in advance through some training. It is desirable.
[0084]
By such intuitive determination, the operator can shift to the diagnostic scan as it is with the transmission condition in an optimal state, such as increasing or decreasing the transmission sound pressure on the spot. For example, if the contrast agent is continuously administered, the effect of the dyeing lasts for about 10 minutes, so the transmission conditions based on the sound described above have been optimized in a short period of time after the administration. Move to the main scan.
[0085]
As a result, optimal transmission conditions can be set in real time in a short time, taking into account individual differences between individual subjects, administered contrast agent concentration, etc. Imaging can be performed under the optimum conditions obtained.
[0086]
For this reason, unlike the prior art, there is no need to read the image data once imaged, so that imaging and diagnosis can be performed in a short time and easily.
[0087]
In addition, with regard to the obtained image, since it is easy to visually distinguish between blood flow and tissue, an image with high diagnostic ability can be obtained from the beginning, so the need for re-imaging is greatly reduced. Reduces burden and effort and improves patient throughput.
[0088]
Furthermore, in order to recognize the disappearance state of the microbubbles, a complicated and burdensome operation for the operator, such as simultaneously displaying images of a plurality of frames while scanning and performing comparative observation, becomes unnecessary. When a sound is used as in this embodiment, it is only necessary to learn the characteristics of the sound, and it is not necessary to visually observe multiple screens while using both hands for the scanning operation, and the skill level required for the operation Is greatly relaxed, the labor involved in diagnosis is greatly reduced, and the work efficiency is improved. Since the burden on the operator is reduced, the rate of occurrence of oversight of an abnormal site during observation is also reduced, which is effective in ensuring the reliability of diagnosis.
[0089]
In the first embodiment, the method of effectively recognizing the disappearance phenomenon of microbubbles has been described as an example applied to flash echo imaging. However, the present method can also be implemented in a normal scanning method.
[0090]
For example, in the case of the normal continuous transmission method, if the scan cross section is changed little by little with respect to an organ substance such as a liver filled with a contrast medium, the microbubbles in the scanned cross section disappear, but the scan cross section Since the transition is made to new undisappeared new sections one after another, bubble disappearance occurs one after another in the new section. In such imaging, if the moving speed when the operator manually operates the probe to move the scan section is non-uniform, the degree of disappearance also changes. For this reason, a difference in the degree of staining occurs in a plurality of captured images, which may affect diagnosis.
[0091]
The present invention can also eliminate the disadvantages caused by such a scan state.
That is, when the present invention is applied to such a scan based on normal continuous transmission, if the degree of bubbles in the cross section that disappears one after another is constant, the generated sound becomes almost constant. This sound, which is intuitive to the operator, requires more easily grasping the degree of bubble disappearance on the spot and raising or lowering the transmitted sound pressure than when reviewing and examining the image after acquiring it. Measures can be taken in a timely manner.
[0092]
Further, as a modification of the embodiment according to the present invention, a function for generating a demonstration sound can be added to the ultrasonic diagnostic apparatus of the first embodiment. This demonstration sound is a sound corresponding to the appropriate difference information di (> 0) described above. For example, as shown in FIG. 1, the operation panel 13 is equipped with a demonstration button 13E, and the sound processor 30 receives operation information from the button 13E via the control circuit 32. The sound processor 30 is a speaker. It is only necessary to generate a demo sound via 31. Of course, the control circuit 32 may directly control the operation of the speaker 31.
[0093]
Therefore, if the operator presses the button 13E before diagnosis, the sound can be heard in advance. Therefore, it is possible to confirm or cultivate the sound feeling that will be heard after entering diagnosis. In addition, by configuring the demo sound so that the intensity, tone color, etc. can be changed as appropriate, the operator can sensibly confirm the change in the disappearance state of the ultrasound contrast agent through the sound before diagnosis. It is possible to perform the operation after shifting to the diagnosis more quickly and accurately.
[0094]
(Second Embodiment)
An ultrasonic diagnostic apparatus according to a second embodiment of the present invention will be described with reference to FIG.
[0095]
This ultrasonic diagnostic apparatus has a function equivalent to that of the ultrasonic diagnostic apparatus of the first embodiment described above, but is different in a signal extraction position to the difference detection circuit 29 as shown in FIG. That is, compared with the apparatus configuration of FIG. 1, the input end of the difference detection circuit 29 is placed in the output stage of the ultrasonic receiving unit 22, that is, in the front stage of the receiver unit 23. Other configurations are the same as or equivalent to those in FIG.
[0096]
As a result, the difference detection circuit 29 inputs an echo signal in the state of an RF signal that is simply subjected to the reception delay addition. That is, the difference detection circuit 29 performs the difference calculation of the various calculation modes described above using this RF signal. By this difference calculation, information such as phase disturbance of the echo signal is obtained. This information reflects random behavior other than disappearance, such as microbubble size change and vibration. Therefore, the sound processor 30 operates in the same manner as described above based on this information, and a sound signal is output from the speaker 31.
[0097]
According to the present embodiment, since the difference detection circuit needs to store the echo signal as an RF signal, the amount of data necessary for storage increases, but since the detection is performed in the state of the RF signal, The ability to detect sensitive microbubbles is improved, and a sound that more accurately reflects the degree of disappearance of microbubbles can be heard.
[0098]
(Third embodiment)
An ultrasonic diagnostic apparatus according to a third embodiment of the present invention will be described with reference to FIGS.
[0099]
This ultrasonic diagnostic apparatus is characterized by a method of outputting information on the disappearance state of microbubbles obtained by the difference.
[0100]
In this apparatus, the sound processor is replaced with an indicator generation circuit 35 as compared with that in the first embodiment described above, and the output destination of the generation circuit 35 is a data synthesizer 26.
[0101]
The inverter generation circuit 35 receives information on the luminance difference di converted into the scalar quantity detected by the difference detection circuit 29, and converts this information into corresponding numerical value or level meter information. This conversion information is displayed on the display 27 via the data synthesizer 26. FIGS. 7A and 7B show two examples displayed in a level meter format. Since this level meter format is often seen on an everyday basis, the operator can intuitively grasp the disappearance state of the microbubbles by looking at it.
[0102]
Note that the display device 27 may display the first frame image and the Nth frame image obtained by the flash echo method using the multi-shot method side by side to visually distinguish the luminance difference. By displaying the scalar quantity di as in this embodiment, a more quantitative value can be notified intuitively. In the case of displaying the scalar quantity, it is sufficient to display only the image of the first frame that has the highest luminance as the diagnostic image.
[0103]
Each of the above-described embodiments is merely an example, and is not intended to limit the scope of the present invention. The scope of the present invention is determined according to the description of the scope of claims, and various embodiments can be implemented without departing from the scope of the present invention.
[0104]
【The invention's effect】
As described above, the ultrasonic diagnostic apparatus according to the present invention is provided. In place According to the contrast echo method, which is performed by administering an ultrasonic contrast agent mainly composed of microbubbles to the subject, the degree of disappearance of the microbubbles is changed to the sensation information such as sound and output. It can be intuitively known that the contrast agent flows into the region of interest.
[0105]
Further, the operator can sensuously recognize (determine) the degree of disappearance of such microbubbles at the time of scanning without looking at continuous frame images. Therefore, for example, if the operator makes a loud sound (high frequency sound), the operator intuitively determines that the degree of bubble disappearance is too large and lowers the output of the transmission pulse. Intuitively determine that the degree of is too small, increase the output of the transmission pulse. This operation can be repeated on the spot in real time, thereby balancing the disappearance of the bubble and the image quality, and finally setting the optimum transmission sound pressure.
[0106]
Therefore, it is not necessary to read out the image after imaging and compare it with each other and read out the degree of disappearance of the microbubbles as before, and can take necessary measures according to the sound in a timely manner at the time of scanning. . For this reason, since only one imaging is required, the necessity for reimaging is remarkably reduced, the operation time is reduced, and the operation time and imaging time can be saved. Moreover, it can be applied to the setting of transmission conditions as well as the blood flow / tissue discrimination in the region of interest, and is highly versatile.
[0107]
In addition, there is no need to compare multiple monitor images with each other during the scan, which simplifies operation and reduces labor, requires much less skill, and provides confidence in diagnosis. Increases the nature.
[0108]
Thereby, information on blood flow dynamics in the blood vessel part and information on hemodynamics at the organ parenchyma level by detection of perfusion can be quantified with higher accuracy and higher precision. As a result, detailed information can be reliably provided for quantification of blood flow information and differential diagnosis.
[Brief description of the drawings]
FIG. 1 is a block diagram of an ultrasonic diagnostic apparatus according to a first embodiment of the present invention.
FIG. 2 is a diagram for explaining the timing of ultrasonic transmission / reception of flash echo imaging using the multi-shot method.
FIG. 3 is a diagram for explaining various difference calculation modes (first to third calculation modes) for an echo signal;
FIG. 4 is a diagram for explaining various difference calculation modes (first to third calculation modes) for an echo signal;
FIG. 5 is a block diagram of an ultrasonic diagnostic apparatus according to a second embodiment of the present invention.
FIG. 6 is a block diagram of an ultrasonic diagnostic apparatus according to a sixth embodiment of the present invention.
FIG. 7 is an explanatory diagram of a display when the disappearance state of microbubbles is expressed by a level meter method.
[Explanation of symbols]
11 Device body
12 Ultrasonic probe (transmission / reception means)
13 Operation panel
14 ECG sensor
21 Transmission unit (transmission / reception means)
22 Receiving unit (transmission / reception means)
23 Receiver unit (transmission / reception means)
24 B mode DSC
25 Doppler unit
26 Data synthesizer
27 Display
28 Image memory
29 Difference detection circuit (acquisition means)
30 Sound processor (transmission means / generation means)
31 Speaker (Transmission means / Output means)
32 Control circuit (including transmission control means. Part of acquisition means and transmission means)
33 Data generation circuit
34 Heart rate detection unit
35 Ingenerator generation circuit (transmission means / generation means)

Claims (11)

An ultrasonic pulse signal is transmitted to a subject administered with an ultrasonic contrast agent mainly composed of microbubbles every time a transmission stop period elapses , and the ultrasonic pulses are sequentially transmitted in order to obtain a plurality of frames at the time of transmission. Transmitting / receiving means for transmitting and receiving an echo signal generated from the subject along with the transmission;
An acquisition means for obtaining a signal intensity difference between frames from the echo signals for the plurality of frames as data representing the degree of disappearance of the ultrasound contrast agent from the echo signal ;
An ultrasonic diagnostic apparatus comprising: a transmission means for transmitting this data to the operator as bodily sensation information. The ultrasonic diagnostic apparatus according to claim 1 ,
The acquisition unit is an ultrasonic diagnostic apparatus that is a unit that calculates a difference between the signal intensities of the frames as a signal intensity difference between the frames. The ultrasonic diagnostic apparatus according to claim 1 ,
The ultrasonic diagnostic apparatus, wherein the acquisition unit is a unit that calculates a difference in the sum of signal intensities in a region of interest set in a part of an image of each frame as a signal intensity difference between the frames. The ultrasonic diagnostic apparatus according to claim 1 ,
The acquisition unit is an ultrasonic diagnostic apparatus that calculates a difference in total signal intensity on a scanning line set for each frame as a signal intensity difference between the frames. The ultrasonic diagnostic apparatus according to claim 1 ,
The ultrasonic diagnostic apparatus, wherein the acquisition unit is a unit that calculates a plurality of signal intensity differences between arbitrary frames as signal intensity differences between the frames. The ultrasonic diagnostic apparatus according to claim 5 .
The acquisition unit is an ultrasonic diagnostic apparatus that is a unit that calculates a signal intensity difference by sequentially changing a combination between adjacent frames as the plurality of signal intensity differences. The ultrasonic diagnostic apparatus according to claim 5 .
The ultrasonic diagnostic apparatus, wherein the acquisition unit is a unit that calculates a signal intensity difference for each region by dividing an image of each frame into a plurality of regions in the depth direction as the plurality of signal intensity differences. The ultrasonic diagnostic apparatus according to any one of claims 1 to 7 ,
The ultrasonic diagnostic apparatus, wherein the bodily sensation information is sound information. 9. The ultrasonic diagnostic apparatus according to claim 8 , wherein the transmission means generates data representing the degree of disappearance of the ultrasonic contrast agent in the sound information data, and outputs the sound information data as sound. And an ultrasonic diagnostic apparatus. The ultrasonic diagnostic apparatus according to claim 9 .
The ultrasonic diagnostic apparatus, wherein the generation means is means for generating data of the sound information by reflecting data indicating a degree of disappearance of the ultrasonic contrast agent in a term of amplitude or time of a reference sound waveform. In an ultrasonic diagnostic apparatus for diagnosing a subject administered with an ultrasonic contrast agent mainly composed of microbubbles,
A transmission unit for transmitting an ultrasonic pulse signal to the subject via a probe;
A receiving unit that receives an echo signal generated from the subject along with the transmission through the probe and delay-adds the echo signal;
A receiver for detecting an echo signal delayed and added by the receiving unit;
A difference detection circuit for detecting a signal difference between frame images from an output signal of the receiving unit or the receiver;
A sound processor that converts the signal difference detected by the difference detection circuit into sound data;
An ultrasonic diagnostic apparatus comprising: a speaker that outputs sound data converted by the sound processor as sound.

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