JP2004167092A

JP2004167092A - Ultrasonic diagnostic apparatus

Info

Publication number: JP2004167092A
Application number: JP2002338434A
Authority: JP
Inventors: Toshio Ito; 壽夫伊藤
Original assignee: Aloka Co Ltd
Current assignee: Hitachi Ltd
Priority date: 2002-11-21
Filing date: 2002-11-21
Publication date: 2004-06-17

Abstract

<P>PROBLEM TO BE SOLVED: To widen the opening for transmitting/receiving ultrasonic waves in an ultrasonic diagnostic apparatus using an ultrasonic vibrator inserted into the celom through a trocar. <P>SOLUTION: This ultrasonic diagnostic apparatus 30 consists of a search unit 40, an apparatus body 50 and a signal cable 48. A hole is bored in the abdomen of an organism 10, and the abdomen is inflated with pressure applied therefrom through the trocar. Another hole is bored in another part on the abdominal wall 12, and a trocar 20 is inserted into the hole, and the search unit 40 is inserted into a trocar 20a. The search unit 40 has a plurality of support parts 70 at the tip. The separation angle of each support part 70 is changed by the operation of a control part 60 at the rear end, so that the shape of the search unit can be "deflated" or "inflated". The ultrasonic vibrator 72 is supported by each support part 70. <P>COPYRIGHT: (C)2004,JPO

Description

【０００１】
【発明の属する技術分野】
本発明は、超音波診断装置に係り、特に、トラカールを通して生体の体腔内に超音波振動子を挿入する超音波診断装置に関する。
【０００２】
【従来の技術】
近年、内視鏡を用いた手術や検査が行われるようになってきている。内視鏡を用いた手術や検査においては、患者の腹部に穴を開け、そこから例えばトラカールを通して気圧を掛けて腹部を膨らませる。トラカールは、内径がおよそ１０ｍｍ程度の中空管で、このトラカールを通して内視鏡、電気メス等の手術具を体腔内に挿入して、内視鏡の観察の下で作業を行う。このような手術や検査において、超音波探触子をトラカールを通して体腔内に挿入し、臓器等の生体組織に当接させ、その超音波探触子によるリアルタイムの超音波断層像をモニタしながら手術や検査を行う方法が採られるようになってきている。
【０００３】
トラカールを通して体腔内に挿入する超音波探触子としては、細長い棒状の探触子軸の側面にリニアアレイタイプの超音波振動子を配置したものがある。また特許文献１には、細長い棒状の探触子軸に関節部を設けて、その先に超音波振動子を配置した探触子ヘッドを設け、探触子ヘッドを探触子軸から傾斜させることができる構成が開示されている。また、内視鏡のように湾曲可能な軸の先端または側面に超音波振動子を設けたもの等も用いられる。
【０００４】
【特許文献１】
特許第２６６４６３１号公報
【０００５】
【発明が解決しようとする課題】
しかし、トラカールの内径は一般には約１０ｍｍと小さいために、トラカールを通して体腔内に挿入できる超音波振動子の大きさに制限が加えられ、十分な検査、診断を行うことができない。例えば、従来例において棒状あるいは湾曲可能な軸の先端に超音波振動子を設けたいわゆるエンドファイヤー型のものでは、超音波送受信の開口はトラカールの内径に制限され、数ｍｍの径に過ぎない。また、棒状あるいは湾曲可能な軸の側面に超音波振動子を設けたいわゆるサイドファイヤー型のものでは、超音波送受信の開口を大きく取ろうとするときはその分トラカールの挿入先端側から体腔内に長く突き出すか、あるいは大きく曲げて長く繰り出す必要があるが、腹腔手術空間の制限のために、十分な突き出し量あるいは繰り出し量を確保することができない。
【０００６】
また、トラカールを通して体腔内に挿入できる超音波振動子の超音波の送受信可能領域に限度があり、生体組織に対して複数方向からの超音波の送受信が困難で、たとえば得られる断層画像にシャドウ等がつくことが多い。
【０００７】
このように、トラカールを通して体腔内に挿入する超音波振動子を用いる超音波診断装置においては、トラカールの内径と、体腔空間等の制約から、開口の広い超音波送受信を行うことが困難であった。また、得られた断層画像にシャドウがつくなど超音波画像の画質に問題があった。
【０００８】
本発明の目的は、かかる従来技術の課題を解決し、トラカールを通して体腔内に挿入する超音波振動子を用いる超音波診断装置において、超音波送受信の開口を広くすることができる超音波診断装置を提供することである。他の目的は、トラカールを通して体腔内に挿入する超音波振動子を用いる超音波診断装置において、超音波画像の画質を向上させることができる超音波診断装置を提供することである。
【０００９】
【課題を解決するための手段】
上記目的を達成するため、本発明に係る超音波診断装置は、トラカールを通して生体の体腔内に挿入されるプローブを含む超音波診断装置において、前記プローブは、超音波を送受信する超音波振動子と、前記超音波振動子を支持面に支持する複数の支持部であって、前記トラカールにプローブが挿入されたときに前記トラカールの挿入先端側から前記体腔内に露出し、相互に離反して広がり広径化し、前記超音波振動子を超音波の照射対象に臨ませる複数の支持部と、前記トラカールにプローブが挿入されたときに前記トラカールの後端側から前記生体の外部に延伸する操作部と、前記操作部の操作量に応じて前記各支持部の離反量を変化させる可変機構と、を備えることを特徴とする。
【００１０】
上記構成により、トラカールを通して生体の体腔内に挿入されるプローブの先端の複数の支持部が、操作部の操作量に応じ相互に離反する離反量を変化させる。したがって、トラカールにプローブを挿入するときは、操作部の操作により各支持部間の離反量を最小にして「すぼめ」、その状態でトラカールを通過させ、支持部がトラカールの挿入先端側から体腔内に露出した状態で、操作部を操作して各支持部間の離反量を増大させて「広げ」ることができる。そして、各支持部を「広げ」た状態では、各超音波振動子の配置も大きく広がり、超音波送受信開口を広くすることができる。
【００１１】
また、前記各支持部は、前記プローブの先端に設けられた回動軸に回動自在に係合し、前記可変機構は、前記操作部の操作量に応じて、前記各支持部の間の離反角度を変化させることが好ましい。
【００１２】
上記構成により、各支持部は回動軸周りに回動できる。この場合各支持部の間の離反量は各支持部の間の離反角度で代表することができ、操作部の操作量に応じ可変機構は離反角度を変化させる。したがって、各支持部を回動軸周りに回動自在に係合するという簡単な構成により、複数の支持部の全体を、あたかも傘のように、操作部の操作量に応じ、すぼめたり、広げたりでき、その広げ具合もコントロールすることができる。
【００１３】
また、前記可変機構は、前記複数の支持部を収容可能な内径を有する外筒と、前記外筒と協働して前記各支持部の離反動作を行う離反動作部材と、を含み、前記外筒に収容された前記複数の支持部の収容量に応じて、前記離反角度を変化させることが好ましい。
【００１４】
上記構成により、外筒を動かして各支持部の離反動作を行わせる。そして、各支持部の離反角度が小さくなるにつれ外筒の内部に各支持部が収容され易くなる。したがって、外筒を動かすという簡単な操作で、離反角度をコントロールすることができる。
【００１５】
また、前記離反動作部材は、前記外筒の端部に向かって、前記各支持部の間の離反角度を最大にする方向に付勢する付勢部材であることが好ましい。上記構成により、離反角度を最大にしようとする付勢部材と、外筒とを協働させて、外筒を動かすことで離反角度を変化させる。したがって、簡単な構成と簡単な操作により離反角度を変化させることができる。
【００１６】
また、前記離反動作部材は、前記各支持部の前記支持面の裏面側と、前記外筒とを接続するリンク部材であることが好ましい。上記構成により、外筒を動かすことでリンク部材を介し各支持部を回動軸まわりに回動させる。したがって、簡単な構成と簡単な操作により離反角度を変化させることができる。
【００１７】
また、前記可変機構は、前記プローブの先端に係合した前記各支持部を、前記プローブ内から回動操作する操作部材と、前記操作部材と前記支持部とを接続するリンク部材と、を含むことが好ましい。上記構成により、プローブ内に設けた操作部材により、各支持部を回動軸まわりに回動させる。したがって、プローブ内に可変機構を収めることができる。
【００１８】
また、本発明に係る超音波診断装置は、前記プローブの先端側に装着されたシール部材を含むことが好ましい。上記構成により、プローブ内に収納される可変機構を、プローブの外部から遮蔽する。したがって、体腔内の生体組織を可変機構によって汚染することを防止し、また、可変機構が生体組織により汚染されることも防止できる。
【００１９】
また、本発明に係る超音波診断装置は、トラカールを通して生体の体腔内に挿入されるプローブと、本体部とを含む超音波診断装置において、前記プローブは、超音波を送受信する超音波振動子と、前記超音波振動子を支持面に支持する複数の支持部であって、前記トラカールにプローブが挿入されたときに前記トラカールの挿入先端側から前記体腔内に露出し、相互に離反して広がり広径化し、前記超音波振動子を超音波の照射対象に臨ませる複数の支持部と、前記トラカールにプローブが挿入されたときに前記トラカールの後端側から前記生体の外部に延伸する操作部と、前記操作部の操作量に応じて前記各支持部の離反量を変化させる可変機構と、を備え、前記本体部は、前記超音波の送受信を制御する送受信制御部と、前記複数の超音波振動子の各出力信号に基づき、合成超音波画像を形成する画像処理部と、を備えることを特徴とする。
【００２０】
上記構成により、複数の超音波振動子からそれぞれ超音波の照射対象に対し超音波を送信し、それぞれのエコー信号に基づいて、超音波画像を合成する。このことで、照射対象について、１つの照射方向からの情報のみならず、多方向からの情報に基づいた画像を得ることができる。
【００２１】
また、前記各支持部は、前記プローブの先端に設けられた回動軸に回動自在に係合するものであり、前記可変機構は、前記操作部の操作量に応じて、前記各支持部の間の離反角度を変化させるものであり、前記送受信制御部は、前記離反角度に応じて形成される不感応領域に向けて、各超音波振動子の前記超音波の送受信方向を偏向させる制御を行うことが好ましい。
【００２２】
回動軸周辺には超音波振動子を配置しにくいので、複数の支持部を組み合わせても、離反角度によっては、回動軸の周辺から照射対象に対し超音波の送受信を行うことが難しく、その部分が超音波画像を形成できない不感応領域となることがおこる。上記構成により、各超音波振動子の送受信方向を不感応領域に向けて偏向させる。したがって、離反角度によらず不感応領域をなくし、広い超音波送受信開口を確保することができる。
【００２３】
また、前記各支持部は、前記プローブの先端に設けられた回動軸に回動自在に係合するものであり、前記可変機構は、前記操作部の操作量に応じて、前記各支持部の回動角度を変化させるものであり、前記各支持部の回動角度を検出する角度センサを含み、前記画像処理部は、前記角度センサにより検出された各回動角度に基づき、前記各超音波振動子の前記超音波の送受信方向を特定し、超音波照射対象の同一観察位置に対する複数方向からの受信信号に基づき、合成超音波画像を形成することが好ましい。
【００２４】
超音波照射対象に対し、複数の支持部を用いることで、同一観察位置について多方向から超音波の送受信を行い、例えば、生体組織の表側から観察した情報と裏側から観察した情報を得ることができる。上記構成により、各支持部の回動角度から各超音波振動子からの超音波の送受信方向を特定する。したがって、特定された各超音波の送受信方向から、複数方向からの受信信号を合成して、例えば、表側から観察した情報と裏側から観察した情報を合成して、シャドウの少ない画質のよい画像を得ることができる。
【００２５】
【発明の実施の形態】
以下、図面を用いて、本発明に係る実施の形態につき詳細に説明する。図１は、生体１０に対し、内視鏡と、超音波診断装置３０を用いて、生体の体腔内の生体組織を観察する様子を示した図である。
【００２６】
一般に、内視鏡を用いた手術または検査においては、生体１０の腹部に穴を開け、そこから例えばトラカールを通して気圧を掛けて腹部を膨らませる。図において、膨らんだ腹部について腹壁１２、体腔１４、体腔内の生体組織１６として胆のう、生体組織１６内の患部１８として胆のう内の結石が示されている。腹壁１２に例えば３箇所の穴を開け、その穴にそれぞれトラカール２０を刺す。トラカール２０としては、例えば内径が１０−１５ｍｍのものを用いることができる。トラカール２０ａには、本実施の形態にかかる超音波診断装置３０のプローブ４０が挿入される。また、トラカール２０ｂには内視鏡が、トラカール２０ｃには電気メス等の手術具が挿入される。トラカールの数は、手術または検査の目的に応じ増減することができる。
【００２７】
超音波診断装置３０は、超音波振動子を備えるプローブ４０と、プローブ４０の超音波振動子に対して超音波の送受信を制御し、受信信号を処理して超音波画像を形成し表示する本体部５０と、プローブ４０と本体部５０とを接続する信号ケーブル４８から構成される。
【００２８】
プローブ４０は、先端に複数の支持部７０を備え、後端部の操作部６０の操作により、各支持部７０の離反角度を変化させ、その形態を「すぼめ」たり、「広げ」たりできるプローブである。超音波振動子７２は、各支持部７０に支持されて設けられる。
【００２９】
図２にプローブ４０の概略図を示す。このプローブ４０は、先端に２個の支持部７０ａ，７０ｂを有するハウジング８０と、ハウジング８０の外周に沿って摺動可能な外筒８６とから構成される。後述するように、外筒８６の後端部が操作部６０の機能を有し、外筒８６の先端部と各支持部７０ａ，７０ｂとの接触部分等が離反角度を変化させる可変機構の機能を有する。図２（ａ）は、外筒８６を支持部７０ａ，７０ｂ側に動かして離反角度を小さくし「すぼめ」た状態、（ｂ）は、外筒８６を（ａ）とは反対側に動かして離反角度を大きくし「広げ」た状態を示す。
【００３０】
ハウジング８０は、筒状の部材で、その先端には回動軸８２ａ，８２ｂが設けられ、２個の支持部７０ａ，７０ｂが回動自在に係合される。回動軸８２ａ，８２ｂの周りには、ハウジング８０と各支持部７０ａ，７０ｂとの間に、各支持部７０ａ，７０ｂを相互に離反させる方向に付勢するコイルばね８４ａ，８４ｂが設けられる。ハウジング８０の長さは、トラカールにプローブ４０が挿入されたとき、トラカールの挿入先端側から体腔内に各支持部７０ａ，７０ｂが露出する長さに設定される。
【００３１】
支持部７０ａ，７０ｂは、超音波振動子７２ａ，７２ｂを支持する機能を有する部材である。図２（ａ）に示すように、回動軸８２ａ，８２ｂの周りに支持部７０ａ，７０ｂを回動させて相互に対向させたときに、その対向面を支持面として、各超音波振動子７２ａ，７２ｂがその送受信面を向かい合わせるようにして支持される。支持部７０ａ，７０ｂにおいて、回動軸８２ａ，８２ｂの周りに、コイルばね８４ａ，８４ｂが設けられる。コイルばね周りの構造については後述する。
【００３２】
超音波振動子７２ａ，７２ｂは、超音波の照射対象に対し超音波の送信およびエコーの受信を行うアレイ振動子である。アレイ振動子は複数の振動素子からなり、このアレイ振動子により超音波ビームが形成される。この超音波ビームは電子走査され、その電子走査方式としては、例えば電子リニア走査や電子セクタ走査を用いることができる。
【００３３】
外筒８６は、ハウジング８０の外周に沿って摺動できる内径と、プローブ４０が挿入されるトラカールの内径よりやや小さ目の外径を有する筒状の部材である。また、その内径は、離反角度を小さくして「すぼめ」た状態のときに各支持部７０ａ，７０ｂをその内部に収納することができるように設定される。外筒８６の長さは、トラカールにプローブ４０が挿入されたとき、外筒８６の後端部が、トラカールの後端側から生体の外部に延伸する程度の長さに設定される。
【００３４】
図３は、プローブ先端の部分断面図で、特に、各支持部の回動軸付近周りに設けられたコイルばね８４ａ，８４ｂが現れる側から見た部分断面図である。図においては、支持部７０ａ，７０ｂが「広げ」られるように外筒８６が上方、すなわちハウジング８０の後端側の方向に動かされた状態を示す。コイルばね８４ａ，８４ｂは、ハウジング８０に設けられた回動軸８２ａ，８２ｂの周りに巻回して設けられ、その一端はハウジング８０の内壁に設けられた回転止め８１により支持され、他端は各支持部７０ａ，７０ｂの内壁に設けられた回転止め７３ａ，７３ｂにより支持される。コイルばね８４ａ，８４ｂの巻き方向は、回動軸８２ａ，８２ｂを中心として、各支持部７０ａ，７０ｂが相互に離反し、離反角度を大きくする方向に付勢されるように設定される。
【００３５】
したがって、コイルばね８４ａ，８４ｂの付勢力により、各支持部７０ａ，７０ｂの支持面の裏面７４ａ，７４ｂと外筒８６の先端部８８とは相互に押し付け合う方向に接触し、外筒８６をハウジング８０に沿って摺動させる操作量に応じて離反角度を変化させることができる。すなわち、外筒８６の後端部が操作部としての機能を有し、外筒８６の先端部８８と各支持部７０ａ，７０ｂの支持面の裏面７４ａ，７４ｂ及びコイルばね８４ａ，８４ｂとが、操作部の操作量に応じて離反角度を変化させる可変機構としての機能を有する。なお、ハウジング８０の下端部８３は、各支持部７０ａ，７０ｂの離反角度の上限を規定するストッパとしての機能を有する。
【００３６】
図３におけるＡ−Ａ線に沿った断面図を図４に示す。支持部７０ａは、断面の外形輪郭が略半円形あるいは略かまぼこ形をなし、内部が中空の薄肉成形部材である。断面において底面側には超音波振動子７２ａが固定される。また、コイルばね８４ａが設けられる近傍の断面においては、仕切り板７５ａにより、内部が２分される。仕切り板７５ａの片側の空間にはコイルばね８４ａが収納され、もう片側の空間には、超音波振動子７２ａからの信号線７７ａが収納される。信号線７７ａは、仕切り板７５ａの片側の専用空間を通り、必要があれば他の信号線とともに信号ケーブル４８を構成し、本体部５０に接続される。
【００３７】
再び図１に戻り、上記構成のプローブ４０の生体組織１６に対する作用について説明する。図１において、まずトラカール２０ａにプローブ４０を挿入する。挿入に際しては、外筒の後端部である操作部６０を操作してプローブ４０の先端部に設けられた２個の支持部７０の離反角度を最初にして「すぼめ」た状態にして行う。次にトラカール２０ｂに挿入された内視鏡を用い、体腔１４内における生体組織１６である胆のうについておよその位置を特定する。そして、内視鏡を見ながら、トラカール２０ａに挿入したプローブ４０の先端部に設けられた２個の支持部７０を生体組織１６である胆のうに近づける。ついで操作部６０を操作して、２個の支持部７０の離反角度を大きくして「広げ」、プローブ４０全体をトラカール２０ａに沿ってさらに押し込み、２個の支持部７０を生体組織１６である胆のうに接触させる。
【００３８】
図においては、離反角度を最大、すなわち、２個の超音波振動子７２をほぼ一平面に並べたと同じ状態にまで「広げ」た場合について示してある。このように、トラカールを通過するときは２個の超音波振動子を「すぼめ」、トラカールを通り抜けて体腔内に露出すると、離反角度を大きくして「広げ」ることで、１個の超音波振動子を単純にトラカールを通した場合に比べ、超音波送受信の開口を２倍に広くすることができる。プローブの先端部に設けられる支持部の数、すなわち超音波振動子の数を、「すぼめ」た状態でトラカールを通過できる数まで増加させることで、さらに超音波送受信の開口を広くすることができる。
【００３９】
図５は、支持部の数を３個または４個とするプローブ１４０の例を示す図である。このプローブ１４０は、先端に３個の支持部１７０ａ，１７０ｂ，１７０ｃを有するハウジング１８０と、ハウジング１８０の外周に沿って摺動可能な外筒１８６とから構成される。３個の支持部１７０ａ，１７０ｂ，１７０ｃは、ハウジング１８０に設けられた回動軸１８２ａ，１８２ｂ，１８２ｃに回動自在に係合される。また、外筒１８６に設けられたリンク支軸１８３ａ，１８３ｂ，１８３ｃと、各支持部１７０ａ，１７０ｂ，１７０ｃの支持面の裏面１７４ａ，１７４ｂ，１７４ｃにそれぞれ設けられたリンク支軸１７３ａ，１７３ｂ，１７３ｃとの間は、それぞれリンク部材１８４ａ，１８４ｂ，１８４ｃにより接続される。
【００４０】
上記構成において、外筒１８６をハウジング１８０の外周に沿って動かすことで、リンク部材１８４ａ，１８４ｂ，１８４ｃを介し各支持部１７０ａ，１７０ｂ，１７０ｃを回動軸１８２ａ，１８２ｂ，１８２ｃまわりに回動させることができる。したがって、外筒１８６をハウジング１８０に沿って摺動させる操作量に応じて、各支持部１７０ａ，１７０ｂ，１７０ｃの離反角度を変化させることができる。
【００４１】
すなわち、外筒１８６の後端部が操作部としての機能を有し、外筒１８６とリンク部材１８４ａ，１８４ｂ，１８４ｃとが、操作部の操作量に応じて離反角度を変化させる可変機構としての機能を有する。図５（ａ）は、外筒１８６を支持部１７０ａ，１７０ｂ，１７０ｃ側に動かして離反角度を小さくし「すぼめ」た状態、（ｂ）は、外筒１８６を（ａ）とは反対側に動かして離反角度を大きくし「広げ」た状態を示す。
【００４２】
上記構成と同様な構成でさらに支持部の数を４個に増加させ、外筒をハウジングに沿って摺動させる操作量に応じて、４個の支持部の離反角度を変化させることもできる。
【００４３】
図６は、外筒を用いず、可変機構をハウジングの内部に収容するプローブ２４０の例を示す図である。このプローブ２４０は、ハウジング２８０を備え、ハウジング２８０に設けられた回動軸２８２ａ，２８２ｂに２個の支持部２７０ａ，２７０ｂが回動自在に係合され、ハウジング２８０内部に、ハウジング２８０の内周に沿って摺動可能な内筒２８６が配置される。そして、内筒２８６に設けられたリンク支軸２８３ａ，２８３ｂと、各支持部２７０ａ，２７０ｂにそれぞれ設けられたリンク支軸２７３ａ，２７３ｂとの間は、それぞれリンク部材２８４ａ，２８４ｂにより接続される。各リンク支軸２７３ａ，２７３ｂとそれに対応する各回動軸２８２ａ，２８２ｂとの距離はできるだけ離すことが望ましい。内筒２８６の長さは、トラカールにプローブ２４０が挿入されたとき、内筒２８６の後端部が、トラカールの後端側から生体の外部に延伸する程度の長さに設定される。
【００４４】
上記構成において、内筒２８６をハウジング２８０の内周に沿って動かすことで、リンク部材２８４ａ，２８４ｂを介し各支持部２７０ａ，２７０ｂを回動軸２８２ａ，２８２ｂまわりに回動させることができる。したがって、内筒２８６をハウジング２８０に沿って摺動させる操作量に応じて、各支持部２７０ａ，２７０ｂの離反角度を変化させることができる。
【００４５】
すなわち、内筒２８６の後端部が操作部としての機能を有し、内筒２８６とリンク部材２８４ａ，２８４ｂとが、操作部の操作量に応じて離反角度を変化させる可変機構としての機能を有する。図６（ａ）は、内筒２８６を支持部２７０ａ，２７０ｂ側から遠ざける方向に動かして離反角度を小さくし「すぼめ」た状態、（ｂ）は、内筒２８６を（ａ）とは反対側に動かして離反角度を大きくし「広げ」た状態を示す。
【００４６】
また、図６において、プローブ２４０の先端側にシール部材２９０を装着することができる。すなわち、可変機構はハウジング２８０の内部に収容されるので、伸縮性を有し、機械的強度が高い材料、例えばフッ素ゴムやＥＰＤＭ（エチレンプロピレンジエンモノマー）素材をシール部材２９０として用い、ハウジング２８０の先端部及び各支持部２７０ａ，２７０ｂの回動軸２８２ａ，２８２ｂ周辺を被覆し、ゴムバンド２９２でしっかり封止する。このことで、体腔内の生体組織を可変機構によって汚染することを防止し、また、可変機構が生体組織により汚染されることも防止できる。また、プローブの使用後の洗浄、滅菌処理が容易となる。
【００４７】
内筒の代わりに、ハウジングの内部に２個の操作部材を設け、その端部にそれぞれリンク支軸を設けて、リンク部材を介して各支持部に設けられたリンク支軸と接続することでも、図６のプローブと同様の作用を得ることができる。
【００４８】
図７は、各支持部の回動軸周りの回動角度を検出するために角度センサを設けた様子を示す図である。プローブ４０は図２で説明したものである。図７において、２個の支持部７０ａ，７０ｂがハウジング８０に回動自在に係合される回動軸８２ａ，８２ｂに角度センサ９０ａ，９０ｂとして小型のエンコーダが設けられる。角度センサ９０ａは、ハウジング８０に対する支持部７０ａの回動軸８２ａ周りの回動角度を検出し、同様に角度センサ９０ｂは、支持部７０ｂの回動角度を検出し、図示されていない信号線を介してそのデータが本体部に送られる。ハウジング８０に対する各支持部７０ａ，７０ｂの回動角度から、２個の支持部間の離反角度θａｂを求めることができる。
【００４９】
図８、図９は、角度センサとしての小型エンコーダの例を示す図である。これらの図において、支持部７０ａの断面図を図４にならって示してある。図８に示す角度センサ９０ａとしての小型エンコーダの例は、光学式エンコーダである。光学式エンコーダは、例えば、ハウジングに設けられた回動軸８２ａに固定されたスリット付円板９２ａと、支持部７０ａの内壁部分に固定されたフォトインタラプタ９４ａとから構成することができる。スリット付円板９２ａは、円板の円周方向に沿って複数のスリットが刻まれ、フォトインタラプタ９４ａは、スリット付円板９２ａを挟んで一方側に発光部、他方側に受光部を備える。この構成において、支持部７０ａが回動軸８２ａ周りに回動すると、スリット付円板９２ａがフォトインタラプタ９４ａに対し相対的に回動し、その回動角度は、円板に刻まれたスリットがフォトインタラプタ９４ａを横切る数で検出できる。スリット付円板にかえて遮光性部分と透光性部分が規則性をもって配置される部材を用いることもできる。
【００５０】
図９における角度センサ９１ａとしてのエンコーダの例は、磁気式エンコーダである。磁気式エンコーダは、例えば、円周の一部に磁石チップが取り付けられた円板９６ａと、磁気検出器９８ａとから構成することができる。円板９６ａは回動軸８２ａに固定され、磁気検出器９８ａは支持部７０ａに固定される。この構成において、支持部７０ａが回動軸８２ａ周りに回動すると、円板９６ａが磁気検出器９８ａに対し相対的に回動し、その回動角度は、円板９６ａに取り付けられた磁石チップと磁気検出器９８ａとの相対関係で検出できる。磁気検出器として例えばＭＲ（磁気抵抗）素子等を用いることができる。
【００５１】
図１０は、複数の超音波振動子を用いた超音波診断装置３０の信号処理系についてのブロック図である。超音波診断装置３０は、プローブ４０において２個の超音波振動子７２ａ，７２ｂと、角度センサ９０ａ，９０ｂを備える。各超音波振動子と各角度センサとは信号ケーブルで本体部５０と接続される。
【００５２】
本体部５０において、送信部３０２ａ，３０２ｂは、各超音波振動子７２ａ，７２ｂ内部に設けられるアレイ振動子の各チャネルごとに遅延された送信信号を供給する機能を有するものである。受信部３０４ａ，３０４ｂは、各超音波振動子７２ａ，７２ｂからのエコー信号を増幅し、各チャネル間の受信信号の位相差を調整する整相加算等の処理を行い、受信信号として信号処理部３０８ａ，３０８ｂに出力する回路である。
【００５３】
送受信制御部３０６は、各送信部３０２ａ，３０２ｂ、各受信部３０４ａ，３０４ｂを制御する機能を有する。また、各支持部の回動角度に応じて、各超音波振動子７２ａ，７２ｂの超音波の送受信方向を制御することもできる。
【００５４】
図１１は、各超音波振動子の超音波の送受信方向を偏向させる制御を行う様子を示す図である。図において、各支持部７０ａ，７０ｂの回動角度が十分大きいとき、各超音波振動子７２ａ，７２ｂの超音波の送受信方向を送受信面に垂直方向ｆａ，ｆｂとすると、超音波振動子が配置されない部分に対応して超音波の送受信が行われない不感応領域Ｘができる。そこで、各超音波振動子７２ａ，７２ｂの超音波の送受信方向を制御し、不感応領域Ｘに向けてｆａ‘，ｆｂ’と偏向させる。
【００５５】
このように、複数の支持部を組み合わせたとき、離反角度によっては、回動軸の周辺から診断対象部位に対し超音波の送受信を行うことが難しく、その部分が超音波画像を形成できない不感応領域となることがおこるが、各超音波振動子の送受信方向を不感応領域に向けて偏向させることで、不感応領域をなくすことができる。したがって、離反角度によらず不感応領域をなくし、広い超音波送受信開口を確保することができる。
【００５６】
信号処理部３０８ａ，３０８ｂは、例えばＢモード信号処理を行うときは、超音波ビームについて各受信部３０４ａ，３０４ｂから出力される整相加算後の受信信号に基づき、エコー信号の包絡振幅を抽出する検波、包絡振幅信号の対数圧縮等の処理を行う機能を有する。Ｂモード信号処理のほか、必要に応じドプラ信号処理の機能を含ませることもできる。
【００５７】
画像処理部３１０は、信号処理部３０８ａ，３０８ｂと接続され、例えばＢモード信号処理出力に対し座標変換やデータ補間等の処理を行ってＢモード断層画像を形成する機能を有する。画像処理の結果は表示部３１２に出力される。
【００５８】
画像処理には、各超音波振動子７２ａ，７２ｂからの各受信信号をそれぞれ信号処理し、画像処理して複数の断層画像を形成するほかに、各超音波振動子７２ａ，７２ｂからの各受信信号に基づいて合成超音波画像を形成することができる。各超音波振動子の超音波の送受信方向は、送受信制御部３０６の制御信号と、各角度センサ９０ａ，９０ｂが出力する各支持部の回動角度から特定できるので、超音波診断対象に対する複数の超音波振動子の送受信がそれぞれ求められ、その受信信号を合成することで、診断対象につきシャドウの少ない画像形成を行うことができる。
【００５９】
例えば、図７に戻って説明すると、この場合の各支持部の回動角度においては、生体組織１６内の患部１８の観察位置Ｐは、支持部７０ａの超音波振動子７２ａの送受信方向ｆａと、支持部７０ｂの超音波振動子７２ｂの送受信方向ｆｂとの２方向が交差する。すなわち、観察位置Ｐは、超音波振動子７２ａの超音波の送受信により、図において右斜め上からの情報を得ることができ、超音波振動子７２ｂの超音波の送受信により、左斜め上からの情報を得ることができる。この２方向からのエコー信号を信号処理し、画像形成において超音波画像を合成することで、観察位置Ｐについてシャドウの少ない良質の画像を得ることができる。
【００６０】
【発明の効果】
本発明に係る超音波診断装置によれば、トラカールを通して体腔内に挿入する超音波振動子を用いる超音波診断装置において、超音波送受信の開口を広くすることができる。本発明に係る超音波診断装置によれば、トラカールを通して体腔内に挿入する超音波振動子を用いる超音波診断装置において、超音波画像の画質を向上させることができる。
【図面の簡単な説明】
【図１】本発明に係る実施の形態の超音波診断装置を用いて、生体の体腔内の生体組織を観察する様子を示した図である。
【図２】本発明に係る実施の形態の超音波診断装置におけるプローブの概略図である。
【図３】コイルばねが現れる側から見たプローブ先端の部分断面図である。
【図４】図３におけるＡ−Ａ線に沿った支持部の断面図である。
【図５】他の実施の形態のプローブの例を示す図である。
【図６】他の実施の形態のプローブの例を示す図である。
【図７】各支持部の回動軸周りの回動角度を検出するために角度センサを設けた様子を示す図である。
【図８】角度センサの例を示す図である。
【図９】他の実施の形態の角度センサの例を示す図である。
【図１０】本発明に係る実施の形態の超音波診断装置の信号処理系についてのブロック図である。
【図１１】各超音波振動子の超音波の送受信方向を偏向させる制御を行う様子を示す図である。
【符号の説明】
１０生体、１２腹壁、１４体腔、１６生体組織、１８患部、２０，２０ａ，２０ｂ，２０ｃトラカール、３０超音波診断装置、４０，１４０，２４０プローブ、４８信号ケーブル、５０本体部、６０操作部、７０，７０ａ，７０ｂ，１７０ａ，１７０ｂ，１７０ｃ，２７０ａ，２７０ｂ支持部、７２，７２ａ，７２ｂ超音波振動子、７４ａ，７４ｂ，１７４ａ，１７４ｂ，１７４ｃ裏面、８０，１８０，２８０ハウジング、８２ａ，８２ｂ，１８２ａ，１８２ｂ，１８２ｃ，２７０ａ，２７０ｂ回動軸、８６，１８６外筒、９０ａ，９０ｂ，９１ａ角度センサ、１８４ａ，１８４ｂ，１８４ｃ，２８４ａ，２８４ｂリンク部材、２８６内筒、２９０シール部材、３０２ａ，３０２ｂ送信部、３０４ａ，３０４ｂ受信部、３０６送受信制御部、３０８ａ，３０８ｂ信号処理部、３１０画像処理部、３１２表示部。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an ultrasonic diagnostic apparatus, and more particularly, to an ultrasonic diagnostic apparatus that inserts an ultrasonic transducer into a body cavity of a living body through a trocar.
[0002]
[Prior art]
In recent years, surgery and inspection using an endoscope have been performed. In an operation or an examination using an endoscope, a hole is made in a patient's abdomen, and air pressure is applied from there through a trocar, for example, to inflate the abdomen. The trocar is a hollow tube having an inner diameter of about 10 mm. Through the trocar, a surgical instrument such as an endoscope or an electric scalpel is inserted into a body cavity, and the operation is performed under observation of the endoscope. In such an operation or inspection, an ultrasonic probe is inserted into a body cavity through a trocar and brought into contact with a living tissue such as an organ, and the operation is performed while monitoring a real-time ultrasonic tomographic image by the ultrasonic probe. And inspection methods are being adopted.
[0003]
As an ultrasonic probe to be inserted into a body cavity through a trocar, there is an ultrasonic probe in which a linear array type ultrasonic transducer is arranged on a side surface of an elongated rod-shaped probe shaft. Further, in Patent Document 1, a joint head is provided on an elongated rod-shaped probe shaft, a probe head having an ultrasonic transducer disposed thereon is provided, and the probe head is tilted from the probe shaft. A configuration is disclosed that can be used. Further, an endoscope provided with an ultrasonic vibrator at the tip or side surface of a bendable shaft, such as an endoscope, is also used.
[0004]
[Patent Document 1]
Japanese Patent No. 2664631
[0005]
[Problems to be solved by the invention]
However, since the inner diameter of the trocar is generally as small as about 10 mm, the size of the ultrasonic transducer that can be inserted into the body cavity through the trocar is limited, and sufficient examination and diagnosis cannot be performed. For example, in a so-called end-fire type in which an ultrasonic vibrator is provided at the tip of a rod-shaped or bendable shaft in a conventional example, the aperture for transmitting and receiving ultrasonic waves is limited to the inner diameter of the trocar and is only a few mm in diameter. In the case of a so-called side fire type in which an ultrasonic vibrator is provided on the side surface of a rod-shaped or bendable shaft, when an opening for transmitting and receiving ultrasonic waves is to be made large, the insertion into the body cavity from the insertion end side of the trocar is correspondingly long. It is necessary to protrude or largely bend and protrude for a long time, but a sufficient protruding amount or protruding amount cannot be secured due to the limitation of the abdominal operation space.
[0006]
In addition, there is a limit to the ultrasonic transmission / reception area of an ultrasonic transducer that can be inserted into a body cavity through a trocar, and it is difficult to transmit and receive ultrasonic waves from a plurality of directions to a living tissue. Is often attached.
[0007]
As described above, in the ultrasonic diagnostic apparatus using the ultrasonic transducer inserted into the body cavity through the trocar, it is difficult to perform ultrasonic transmission / reception with a wide opening due to the inner diameter of the trocar and restrictions on the body cavity space and the like. . In addition, there is a problem in the image quality of the ultrasonic image, such as a shadow is formed on the obtained tomographic image.
[0008]
An object of the present invention is to solve the problems of the prior art, and to provide an ultrasonic diagnostic apparatus using an ultrasonic transducer inserted into a body cavity through a trocar, in which an ultrasonic transmitting / receiving aperture can be widened. To provide. Another object of the present invention is to provide an ultrasonic diagnostic apparatus that uses an ultrasonic transducer inserted into a body cavity through a trocar and that can improve the quality of an ultrasonic image.
[0009]
[Means for Solving the Problems]
To achieve the above object, an ultrasonic diagnostic apparatus according to the present invention is an ultrasonic diagnostic apparatus that includes a probe inserted into a body cavity of a living body through a trocar, wherein the probe has an ultrasonic transducer that transmits and receives ultrasonic waves. A plurality of support portions for supporting the ultrasonic vibrator on a support surface, wherein the plurality of support portions are exposed into the body cavity from the insertion end side of the trocar when a probe is inserted into the trocar, and spread away from each other. A plurality of supporting portions that have a large diameter and face the ultrasonic vibrator toward an object to be irradiated with ultrasonic waves, and an operation unit that extends from the rear end side of the trocar to the outside of the living body when a probe is inserted into the trocar. And a variable mechanism for changing an amount of separation of each of the support portions according to an operation amount of the operation portion.
[0010]
According to the above configuration, the plurality of support portions at the distal end of the probe inserted into the body cavity of the living body through the trocar change the amount of separation from each other in accordance with the operation amount of the operation unit. Therefore, when inserting the probe into the trocar, the amount of separation between the support parts is minimized by operating the operation part, and `` purging '', the trocar is passed in that state, and the support part is inserted into the body cavity from the insertion end side of the trocar. In the state of being exposed, the operating section can be operated to increase the amount of separation between the support sections and “spread”. Then, in a state where each support portion is "spread", the arrangement of each ultrasonic transducer is greatly expanded, and the ultrasonic transmission / reception aperture can be widened.
[0011]
Further, each of the support portions is rotatably engaged with a rotation shaft provided at a tip of the probe, and the variable mechanism is configured to move between the support portions according to an operation amount of the operation portion. It is preferable to change the separation angle.
[0012]
With the above configuration, each support portion can rotate around the rotation axis. In this case, the separation amount between the support portions can be represented by the separation angle between the support portions, and the variable mechanism changes the separation angle according to the operation amount of the operation portion. Therefore, with a simple configuration in which each support portion is rotatably engaged around a rotation axis, the entirety of the plurality of support portions can be narrowed or widened according to the operation amount of the operation portion, like an umbrella. You can also control the spread.
[0013]
In addition, the variable mechanism includes an outer cylinder having an inner diameter capable of accommodating the plurality of support portions, and a separating operation member that performs a separating operation of each of the support portions in cooperation with the outer cylinder. It is preferable that the separation angle is changed in accordance with the accommodation amount of the plurality of support portions accommodated in a cylinder.
[0014]
With the above configuration, the outer cylinder is moved to perform the separating operation of each support portion. Then, as the separation angles of the support portions become smaller, the support portions are more easily accommodated in the outer cylinder. Therefore, the separation angle can be controlled by a simple operation of moving the outer cylinder.
[0015]
Further, it is preferable that the separating operation member is an urging member that urges toward an end of the outer cylinder in a direction that maximizes a separating angle between the support portions. With the above configuration, the biasing member that attempts to maximize the separation angle and the outer cylinder cooperate to move the outer cylinder, thereby changing the separation angle. Therefore, the separation angle can be changed by a simple configuration and a simple operation.
[0016]
Further, it is preferable that the separation operation member is a link member that connects the back surface of the support surface of each support portion to the outer cylinder. According to the above configuration, each support portion is rotated around the rotation axis via the link member by moving the outer cylinder. Therefore, the separation angle can be changed by a simple configuration and a simple operation.
[0017]
In addition, the variable mechanism includes an operation member that rotates the support unit engaged with the tip of the probe from within the probe, and a link member that connects the operation member and the support unit. Is preferred. With the above configuration, each support portion is rotated around the rotation axis by the operation member provided in the probe. Therefore, the variable mechanism can be housed in the probe.
[0018]
Further, the ultrasonic diagnostic apparatus according to the present invention preferably includes a seal member attached to a distal end side of the probe. According to the above configuration, the variable mechanism housed in the probe is shielded from the outside of the probe. Therefore, it is possible to prevent the living tissue in the body cavity from being contaminated by the variable mechanism, and to prevent the variable mechanism from being contaminated by the living tissue.
[0019]
Further, an ultrasonic diagnostic apparatus according to the present invention is a probe inserted into a body cavity of a living body through a trocar, and an ultrasonic diagnostic apparatus including a main body, wherein the probe is an ultrasonic transducer that transmits and receives ultrasonic waves. A plurality of support portions for supporting the ultrasonic vibrator on a support surface, wherein the plurality of support portions are exposed into the body cavity from the insertion end side of the trocar when a probe is inserted into the trocar, and spread away from each other. A plurality of supporting portions that have a large diameter and face the ultrasonic vibrator toward an object to be irradiated with ultrasonic waves, and an operation unit that extends from the rear end side of the trocar to the outside of the living body when a probe is inserted into the trocar. And a variable mechanism that changes the amount of separation of each of the support units according to the operation amount of the operation unit, wherein the main body unit controls the transmission and reception of the ultrasonic waves, On the basis of the output signals of the wave vibrator, and an image processing unit for forming a composite ultrasound image, comprising: a.
[0020]
According to the above configuration, ultrasonic waves are transmitted from the plurality of ultrasonic transducers to the ultrasonic irradiation target, and an ultrasonic image is synthesized based on the respective echo signals. This makes it possible to obtain an image of an irradiation target based on information from not only one irradiation direction but also information from multiple directions.
[0021]
In addition, each of the support portions is rotatably engaged with a rotation shaft provided at the tip of the probe, and the variable mechanism is configured to control each of the support portions in accordance with an operation amount of the operation portion. The transmission / reception control unit controls the deflection of the ultrasonic transmission / reception direction of each ultrasonic transducer toward an insensitive area formed according to the separation angle. Is preferably performed.
[0022]
Since it is difficult to arrange an ultrasonic transducer around the rotation axis, even if a plurality of support parts are combined, it is difficult to transmit and receive ultrasonic waves to and from the irradiation target from around the rotation axis, depending on the separation angle. That portion may become an insensitive area where an ultrasonic image cannot be formed. According to the above configuration, the transmission / reception direction of each ultrasonic transducer is deflected toward the insensitive region. Therefore, the insensitive region can be eliminated regardless of the separation angle, and a wide ultrasonic transmission / reception aperture can be secured.
[0023]
In addition, each of the support portions is rotatably engaged with a rotation shaft provided at the tip of the probe, and the variable mechanism is configured to control each of the support portions in accordance with an operation amount of the operation portion. And an angle sensor for detecting a rotation angle of each of the support units. The image processing unit is configured to change each of the ultrasonic waves based on each of the rotation angles detected by the angle sensor. It is preferable that a transmission / reception direction of the ultrasonic wave of the transducer is specified, and a composite ultrasonic image is formed based on reception signals from a plurality of directions with respect to the same observation position of the ultrasonic irradiation target.
[0024]
By using a plurality of supports for the ultrasonic irradiation target, it is possible to transmit and receive ultrasonic waves from multiple directions for the same observation position, for example, to obtain information observed from the front side and information observed from the back side of the biological tissue it can. According to the above configuration, the transmission / reception direction of the ultrasonic wave from each ultrasonic transducer is specified from the rotation angle of each support portion. Therefore, from the specified transmission / reception direction of each ultrasonic wave, the received signals from multiple directions are combined, for example, the information observed from the front side and the information observed from the back side are combined, and an image with good image quality with little shadow is obtained. Obtainable.
[0025]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a diagram showing a state of observing a living tissue in a body cavity of a living body 10 using an endoscope and an ultrasonic diagnostic apparatus 30 with respect to the living body 10.
[0026]
In general, in an operation or an examination using an endoscope, a hole is made in the abdomen of the living body 10, and air pressure is applied from there through a trocar, for example, to inflate the abdomen. In the figure, the abdominal wall 12, the body cavity 14, the living tissue 16 in the body cavity are gall bladders, and the affected area 18 in the living tissue 16 is a gall bladder stone in the swollen abdomen. For example, three holes are made in the abdominal wall 12, and trocars 20 are pierced into the holes, respectively. As the trocar 20, for example, one having an inner diameter of 10 to 15 mm can be used. The probe 40 of the ultrasonic diagnostic apparatus 30 according to the present embodiment is inserted into the trocar 20a. An endoscope is inserted into the trocar 20b, and a surgical instrument such as an electric scalpel is inserted into the trocar 20c. The number of trocars can be increased or decreased depending on the purpose of the surgery or examination.
[0027]
An ultrasonic diagnostic apparatus 30 includes a probe 40 having an ultrasonic transducer, a main body that controls transmission and reception of ultrasonic waves to and from the ultrasonic transducer of the probe 40, processes received signals to form and display an ultrasonic image. A signal cable 48 for connecting the probe 50 to the main body 50.
[0028]
The probe 40 is provided with a plurality of support portions 70 at the front end, and by changing the separation angle of each support portion 70 by operating the operation portion 60 at the rear end portion, a probe capable of “purging” or “spreading” the form. It is. The ultrasonic vibrator 72 is provided to be supported by each support part 70.
[0029]
FIG. 2 shows a schematic diagram of the probe 40. The probe 40 includes a housing 80 having two support portions 70a and 70b at the distal end, and an outer cylinder 86 slidable along the outer periphery of the housing 80. As will be described later, the rear end of the outer tube 86 has the function of the operation unit 60, and the contact portion between the front end of the outer tube 86 and each of the support portions 70a, 70b, etc., functions as a variable mechanism for changing the separation angle. Having. FIG. 2A shows a state in which the outer cylinder 86 is moved toward the support portions 70a and 70b to reduce the separation angle and is "pulled", and FIG. 2B is a diagram in which the outer cylinder 86 is moved to the opposite side to FIG. This shows a state where the separation angle is increased and “spread”.
[0030]
The housing 80 is a cylindrical member, and the tip thereof is provided with rotation shafts 82a and 82b, and the two support portions 70a and 70b are rotatably engaged. Around the rotation shafts 82a and 82b, coil springs 84a and 84b are provided between the housing 80 and the support portions 70a and 70b to urge the support portions 70a and 70b away from each other. The length of the housing 80 is set to a length such that when the probe 40 is inserted into the trocar, the support portions 70a and 70b are exposed into the body cavity from the insertion end side of the trocar.
[0031]
The support portions 70a and 70b are members having a function of supporting the ultrasonic transducers 72a and 72b. As shown in FIG. 2A, when the support portions 70a and 70b are rotated around the rotation shafts 82a and 82b so as to be opposed to each other, each of the ultrasonic transducers is used with the opposed surface as a support surface. 72a and 72b are supported with their transmitting and receiving surfaces facing each other. In the support portions 70a and 70b, coil springs 84a and 84b are provided around the rotation shafts 82a and 82b. The structure around the coil spring will be described later.
[0032]
The ultrasonic vibrators 72a and 72b are array vibrators that transmit ultrasonic waves and receive echoes to an ultrasonic irradiation target. The array transducer includes a plurality of transducers, and an ultrasonic beam is formed by the array transducer. The ultrasonic beam is electronically scanned. As the electronic scanning method, for example, electronic linear scanning or electronic sector scanning can be used.
[0033]
The outer cylinder 86 is a cylindrical member having an inner diameter that can slide along the outer circumference of the housing 80 and an outer diameter that is slightly smaller than the inner diameter of the trocar into which the probe 40 is inserted. Further, the inner diameter is set so that the support portions 70a and 70b can be accommodated therein when the separation angle is small and the state is "pulled". The length of the outer cylinder 86 is set to such a length that the rear end of the outer cylinder 86 extends outside the living body from the rear end of the trocar when the probe 40 is inserted into the trocar.
[0034]
FIG. 3 is a partial cross-sectional view of the tip of the probe, in particular, a partial cross-sectional view seen from the side where the coil springs 84a and 84b provided around the rotation axis of each support portion appear. The figure shows a state in which the outer cylinder 86 has been moved upward, that is, toward the rear end of the housing 80 so that the support portions 70a and 70b are "spread". The coil springs 84a and 84b are provided so as to be wound around rotating shafts 82a and 82b provided on the housing 80. One end of the coil springs 84a and 84b is supported by a rotation stopper 81 provided on the inner wall of the housing 80, and the other end is provided. It is supported by rotation stoppers 73a and 73b provided on the inner walls of the support portions 70a and 70b. The winding directions of the coil springs 84a and 84b are set so that the support portions 70a and 70b are separated from each other about the rotation shafts 82a and 82b, and are biased in a direction to increase the separation angle.
[0035]
Therefore, by the urging forces of the coil springs 84a and 84b, the back surfaces 74a and 74b of the support surfaces of the support portions 70a and 70b and the distal end portion 88 of the outer tube 86 come into contact with each other in a direction in which they are pressed against each other. The separation angle can be changed according to the operation amount of sliding along 80. That is, the rear end of the outer cylinder 86 has a function as an operation unit, and the front end 88 of the outer cylinder 86, the back surfaces 74a and 74b of the support surfaces of the support portions 70a and 70b, and the coil springs 84a and 84b It has a function as a variable mechanism that changes the separation angle according to the operation amount of the operation unit. Note that the lower end portion 83 of the housing 80 has a function as a stopper that defines the upper limit of the separation angle between the support portions 70a and 70b.
[0036]
FIG. 4 is a cross-sectional view taken along the line AA in FIG. The support portion 70a is a thin-walled molded member having a substantially semicircular or substantially semicylindrical outer contour in cross section and a hollow inside. An ultrasonic vibrator 72a is fixed to the bottom surface in the cross section. In the cross section near the coil spring 84a, the inside is divided into two by the partition plate 75a. A coil spring 84a is housed in a space on one side of the partition plate 75a, and a signal line 77a from the ultrasonic transducer 72a is housed in the space on the other side. The signal line 77a passes through a dedicated space on one side of the partition plate 75a, forms a signal cable 48 together with other signal lines if necessary, and is connected to the main body 50.
[0037]
Returning to FIG. 1 again, the operation of the probe 40 having the above configuration on the living tissue 16 will be described. In FIG. 1, the probe 40 is first inserted into the trocar 20a. At the time of insertion, the operating portion 60, which is the rear end of the outer cylinder, is operated to set the separation angle of the two support portions 70 provided at the distal end of the probe 40 to the initial state and to "pull". Next, using an endoscope inserted into the trocar 20b, an approximate position of the gallbladder, which is the living tissue 16 in the body cavity 14, is specified. Then, while watching the endoscope, the two support portions 70 provided at the distal end of the probe 40 inserted into the trocar 20a are brought closer to the gallbladder, which is the living tissue 16. Then, by operating the operation unit 60, the separation angle of the two support units 70 is increased to “spread”, and the entire probe 40 is further pushed along the trocar 20a, so that the two support units 70 are the living tissue 16. Contact with gall bladder.
[0038]
In the drawing, the case where the separation angle is maximized, that is, the case where the two ultrasonic transducers 72 are "spread" to the same state as being arranged substantially on one plane is shown. Thus, when passing through the trocar, the two ultrasonic transducers are “pursed”, and when they pass through the trocar and are exposed in the body cavity, the separation angle is increased and “spread”, thereby making one ultrasonic The aperture for transmitting and receiving ultrasonic waves can be doubled as compared with the case where the vibrator is simply passed through the trocar. By increasing the number of supports provided at the tip of the probe, that is, the number of ultrasonic transducers, to the number that can pass through the trocar in the "pursed" state, the aperture for ultrasonic transmission and reception can be further widened. .
[0039]
FIG. 5 is a diagram illustrating an example of the probe 140 having three or four support portions. The probe 140 includes a housing 180 having three support portions 170a, 170b, and 170c at the tip, and an outer cylinder 186 slidable along the outer periphery of the housing 180. The three support portions 170a, 170b, 170c are rotatably engaged with rotating shafts 182a, 182b, 182c provided on the housing 180. Also, link support shafts 183a, 183b, 183c provided on the outer cylinder 186 and link support shafts 173a, 173b, 173c provided on the back surfaces 174a, 174b, 174c of the support surfaces of the support portions 170a, 170b, 170c, respectively. Are connected by link members 184a, 184b, and 184c, respectively.
[0040]
In the above configuration, by moving the outer cylinder 186 along the outer periphery of the housing 180, the support portions 170a, 170b, 170c are rotated around the rotation shafts 182a, 182b, 182c via the link members 184a, 184b, 184c. be able to. Therefore, the separation angles of the support portions 170a, 170b, 170c can be changed according to the operation amount of sliding the outer cylinder 186 along the housing 180.
[0041]
That is, the rear end of the outer cylinder 186 has a function as an operation unit, and the outer cylinder 186 and the link members 184a, 184b, 184c function as a variable mechanism that changes the separation angle according to the operation amount of the operation unit. Has functions. FIG. 5A shows a state in which the outer cylinder 186 is moved toward the support portions 170a, 170b, and 170c to reduce the separation angle and is "pulled", and FIG. It shows a state in which it is moved to increase the separation angle and “spread”.
[0042]
With the configuration similar to the above configuration, the number of support portions can be further increased to four, and the separation angles of the four support portions can be changed according to the operation amount of sliding the outer cylinder along the housing.
[0043]
FIG. 6 is a diagram illustrating an example of a probe 240 that accommodates a variable mechanism inside a housing without using an outer cylinder. The probe 240 includes a housing 280, and two support portions 270 a and 270 b are rotatably engaged with rotation shafts 282 a and 282 b provided on the housing 280, and inside the housing 280, the inner circumference of the housing 280 is provided. An inner cylinder 286 slidable along is disposed. The link support shafts 283a and 283b provided on the inner cylinder 286 and the link support shafts 273a and 273b provided on the support portions 270a and 270b are connected by link members 284a and 284b, respectively. It is desirable that the distance between each link support shaft 273a, 273b and each corresponding rotation shaft 282a, 282b be as far as possible. The length of the inner cylinder 286 is set so that the rear end of the inner cylinder 286 extends from the rear end of the trocar to the outside of the living body when the probe 240 is inserted into the trocar.
[0044]
In the above-described configuration, by moving the inner cylinder 286 along the inner periphery of the housing 280, the support portions 270a and 270b can be rotated around the rotation shafts 282a and 282b via the link members 284a and 284b. Therefore, the separation angle between the support portions 270a and 270b can be changed according to the operation amount of sliding the inner cylinder 286 along the housing 280.
[0045]
That is, the rear end of the inner cylinder 286 has a function as an operation unit, and the inner cylinder 286 and the link members 284a and 284b have a function as a variable mechanism that changes the separation angle according to the operation amount of the operation unit. Have. FIG. 6A shows a state in which the inner cylinder 286 is moved in a direction away from the support portions 270a and 270b to reduce the separation angle and is "pulled", and FIG. 6B shows a state in which the inner cylinder 286 is on the opposite side to FIG. To show the state where the angle of separation is increased to "spread".
[0046]
In FIG. 6, a seal member 290 can be attached to the distal end side of the probe 240. That is, since the variable mechanism is housed inside the housing 280, a material having elasticity and high mechanical strength, for example, a fluorine rubber or an EPDM (ethylene propylene diene monomer) material is used as the seal member 290, and The tip portion and the periphery of the rotation shafts 282a, 282b of the support portions 270a, 270b are covered and tightly sealed with a rubber band 292. This can prevent the living tissue in the body cavity from being contaminated by the variable mechanism, and also prevent the variable mechanism from being contaminated by the living tissue. Further, washing and sterilization after use of the probe are facilitated.
[0047]
Instead of the inner cylinder, two operating members may be provided inside the housing, link support shafts may be provided at the ends thereof, and connected to the link support shafts provided on the respective support portions via the link members. And the same operation as the probe of FIG. 6 can be obtained.
[0048]
FIG. 7 is a diagram illustrating a state in which an angle sensor is provided to detect a rotation angle of each support portion around a rotation axis. The probe 40 is the one described in FIG. In FIG. 7, small encoders are provided as angle sensors 90a and 90b on rotation shafts 82a and 82b in which two support portions 70a and 70b are rotatably engaged with a housing 80. The angle sensor 90a detects the rotation angle of the support portion 70a around the rotation axis 82a with respect to the housing 80, and similarly, the angle sensor 90b detects the rotation angle of the support portion 70b, and connects a signal line (not shown). The data is sent to the main unit via the main unit. The separation angle θab between the two support portions can be obtained from the rotation angle of each of the support portions 70a and 70b with respect to the housing 80.
[0049]
8 and 9 are diagrams illustrating examples of a small encoder as an angle sensor. In these figures, a cross-sectional view of the support portion 70a is shown in FIG. An example of a small encoder as the angle sensor 90a shown in FIG. 8 is an optical encoder. The optical encoder can be composed of, for example, a disc 92a with a slit fixed to a rotating shaft 82a provided in a housing, and a photo interrupter 94a fixed to an inner wall portion of the support 70a. The slit disc 92a has a plurality of slits cut along the circumferential direction of the disc, and the photo interrupter 94a has a light emitting unit on one side and a light receiving unit on the other side across the slit disc 92a. In this configuration, when the support portion 70a rotates around the rotation shaft 82a, the slit disk 92a rotates relatively to the photointerrupter 94a, and the rotation angle is determined by the slit formed in the disk. It can be detected by the number that crosses the photo interrupter 94a. A member in which the light-shielding portion and the light-transmitting portion are arranged regularly may be used instead of the disk with slits.
[0050]
An example of the encoder as the angle sensor 91a in FIG. 9 is a magnetic encoder. The magnetic encoder can be composed of, for example, a disk 96a in which a magnet chip is attached to a part of the circumference, and a magnetic detector 98a. The disk 96a is fixed to the rotating shaft 82a, and the magnetic detector 98a is fixed to the support 70a. In this configuration, when the support portion 70a rotates around the rotation shaft 82a, the disk 96a rotates relatively to the magnetic detector 98a, and the rotation angle is determined by the magnet chip attached to the disk 96a. And the magnetic detector 98a. For example, an MR (magnetic resistance) element or the like can be used as the magnetic detector.
[0051]
FIG. 10 is a block diagram of a signal processing system of the ultrasonic diagnostic apparatus 30 using a plurality of ultrasonic transducers. The ultrasonic diagnostic apparatus 30 includes two ultrasonic transducers 72a and 72b and angle sensors 90a and 90b in the probe 40. Each ultrasonic transducer and each angle sensor are connected to the main unit 50 by a signal cable.
[0052]
In the main unit 50, the transmission units 302a and 302b have a function of supplying a transmission signal delayed for each channel of the array transducer provided inside each of the ultrasonic transducers 72a and 72b. The receiving units 304a and 304b amplify the echo signals from the ultrasonic transducers 72a and 72b, perform processing such as phasing addition to adjust the phase difference between the received signals between the channels, and perform signal processing as a received signal. This is a circuit for outputting to 308a and 308b.
[0053]
The transmission / reception control unit 306 has a function of controlling the transmission units 302a and 302b and the reception units 304a and 304b. In addition, the transmitting and receiving directions of the ultrasonic waves of each of the ultrasonic transducers 72a and 72b can be controlled in accordance with the rotation angle of each support.
[0054]
FIG. 11 is a diagram illustrating a state in which control is performed to deflect the transmission / reception direction of the ultrasonic wave of each ultrasonic transducer. In the drawing, when the rotation angle of each of the support portions 70a and 70b is sufficiently large, the ultrasonic transmission and reception directions of the ultrasonic transducers 72a and 72b are set to the directions fa and fb perpendicular to the transmission and reception surface, and the ultrasonic transducers are arranged. A non-sensitive area X in which the transmission and reception of the ultrasonic wave is not performed is generated corresponding to the part that is not performed. Therefore, the transmission / reception direction of the ultrasonic wave of each of the ultrasonic transducers 72a and 72b is controlled to deflect it to fa 'and fb' toward the insensitive region X.
[0055]
As described above, when a plurality of supporting portions are combined, it is difficult to transmit and receive ultrasonic waves to and from a portion to be diagnosed from around the rotation axis depending on the separation angle, and the insensitive portion cannot form an ultrasonic image. In some cases, the area becomes an area, but the insensitive area can be eliminated by deflecting the transmission / reception direction of each ultrasonic transducer toward the insensitive area. Therefore, the insensitive region can be eliminated regardless of the separation angle, and a wide ultrasonic transmission / reception aperture can be secured.
[0056]
For example, when performing the B-mode signal processing, the signal processing units 308a and 308b extract the envelope amplitude of the echo signal based on the reception signals after the phasing addition output from the reception units 304a and 304b for the ultrasonic beam. It has a function of performing processes such as detection and logarithmic compression of the envelope amplitude signal. In addition to the B-mode signal processing, a function of Doppler signal processing can be included as necessary.
[0057]
The image processing unit 310 is connected to the signal processing units 308a and 308b, and has a function of forming a B-mode tomographic image by performing processing such as coordinate conversion and data interpolation on the B-mode signal processing output. The result of the image processing is output to the display unit 312.
[0058]
In the image processing, each received signal from each of the ultrasonic transducers 72a and 72b is subjected to signal processing, and image processing is performed to form a plurality of tomographic images. In addition, each received signal from each of the ultrasonic transducers 72a and 72b is A composite ultrasound image can be formed based on the signal. The direction of transmission and reception of ultrasonic waves by each ultrasonic transducer can be specified from the control signal of the transmission / reception control unit 306 and the rotation angle of each support unit output by each of the angle sensors 90a and 90b. Transmission and reception of the ultrasonic transducers are required, respectively, and by synthesizing the received signals, it is possible to form an image with less shadow on the diagnosis target.
[0059]
For example, referring back to FIG. 7, at the rotation angle of each support in this case, the observation position P of the diseased part 18 in the living tissue 16 is different from the transmission / reception direction fa of the ultrasonic transducer 72a of the support 70a. And the transmitting / receiving direction fb of the ultrasonic vibrator 72b of the support portion 70b intersects. That is, the observation position P can obtain information from the upper right in the figure by transmitting and receiving the ultrasonic wave from the ultrasonic transducer 72a, and can obtain information from the upper left by transmitting and receiving the ultrasonic wave from the ultrasonic transducer 72b. Information can be obtained. By processing the echo signals from these two directions and synthesizing an ultrasonic image in image formation, a high-quality image with few shadows at the observation position P can be obtained.
[0060]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to the ultrasonic diagnostic apparatus which concerns on this invention, in the ultrasonic diagnostic apparatus which uses an ultrasonic transducer inserted in a body cavity through a trocar, the opening of ultrasonic transmission / reception can be widened. ADVANTAGE OF THE INVENTION According to the ultrasonic diagnostic apparatus which concerns on this invention, the image quality of an ultrasonic image can be improved in the ultrasonic diagnostic apparatus which uses an ultrasonic transducer inserted in a body cavity through a trocar.
[Brief description of the drawings]
FIG. 1 is a diagram showing a state in which a living tissue in a body cavity of a living body is observed using an ultrasonic diagnostic apparatus according to an embodiment of the present invention.
FIG. 2 is a schematic diagram of a probe in the ultrasonic diagnostic apparatus according to the embodiment of the present invention.
FIG. 3 is a partial sectional view of a probe tip viewed from a side where a coil spring appears.
FIG. 4 is a cross-sectional view of the support section taken along line AA in FIG.
FIG. 5 is a diagram illustrating an example of a probe according to another embodiment.
FIG. 6 is a diagram illustrating an example of a probe according to another embodiment.
FIG. 7 is a diagram illustrating a state in which an angle sensor is provided to detect a rotation angle of each support around a rotation axis.
FIG. 8 is a diagram illustrating an example of an angle sensor.
FIG. 9 is a diagram illustrating an example of an angle sensor according to another embodiment.
FIG. 10 is a block diagram of a signal processing system of the ultrasonic diagnostic apparatus according to the embodiment of the present invention.
FIG. 11 is a diagram illustrating a state in which control is performed to deflect an ultrasonic transmission / reception direction of each ultrasonic transducer.
[Explanation of symbols]
Reference Signs List 10 living body, 12 abdominal wall, 14 body cavity, 16 living tissue, 18 affected part, 20, 20a, 20b, 20c trocar, 30 ultrasonic diagnostic apparatus, 40, 140, 240 probe, 48 signal cable, 50 body section, 60 operation section, 70, 70a, 70b, 170a, 170b, 170c, 270a, 270b Support, 72, 72a, 72b Ultrasonic transducer, 74a, 74b, 174a, 174b, 174c Back, 80, 180, 280 Housing, 82a, 82b, 182a, 182b, 182c, 270a, 270b Rotating shaft, 86, 186 outer cylinder, 90a, 90b, 91a Angle sensor, 184a, 184b, 184c, 284a, 284b Link member, 286 inner cylinder, 290 seal member, 302a, 302b Transmitter, 304a, 304b Receiver, 30 Reception control unit, 308a, 308b signal processing section, 310 image processing unit, 312 display unit.

Claims

In an ultrasonic diagnostic apparatus including a probe inserted into a body cavity of a living body through a trocar,
The probe is
An ultrasonic transducer for transmitting and receiving ultrasonic waves,
A plurality of support portions for supporting the ultrasonic vibrator on a support surface, wherein the plurality of support portions are exposed into the body cavity from the insertion end side of the trocar when a probe is inserted into the trocar, and spread apart and spread apart from each other. Diameter, a plurality of support portions facing the ultrasonic oscillator to the ultrasonic irradiation target,
An operation unit extending from the rear end side of the trocar to the outside of the living body when a probe is inserted into the trocar,
A variable mechanism that changes the separation amount of each of the support units according to the operation amount of the operation unit,
An ultrasonic diagnostic apparatus comprising:

The ultrasonic diagnostic apparatus according to claim 1,
Each of the support portions is rotatably engaged with a rotation shaft provided at the tip of the probe,
The ultrasonic diagnostic apparatus, wherein the variable mechanism changes a separation angle between the support units according to an operation amount of the operation unit.

The ultrasonic diagnostic apparatus according to claim 2,
The variable mechanism,
An outer cylinder having an inner diameter capable of accommodating the plurality of support portions,
A separating operation member that performs a separating operation of each of the support portions in cooperation with the outer cylinder;
Including
The ultrasonic diagnostic apparatus according to claim 1, wherein the separation angle is changed according to an accommodation amount of the plurality of support portions accommodated in the outer cylinder.

The ultrasonic diagnostic apparatus according to claim 3,
The ultrasonic diagnostic apparatus according to claim 1, wherein the separating operation member is an urging member that urges toward an end of the outer cylinder in a direction that maximizes a separating angle between the support portions.

The ultrasonic diagnostic apparatus according to claim 3,
The ultrasonic diagnostic apparatus, wherein the separating member is a link member that connects a back surface of the support surface of each of the support portions to the outer cylinder.

The ultrasonic diagnostic apparatus according to claim 2,
The variable mechanism,
An operating member for rotating the respective support portions engaged with the tip of the probe from inside the probe,
A link member that connects the operation member and the support portion,
An ultrasonic diagnostic apparatus comprising:

The ultrasonic diagnostic apparatus according to claim 6,
An ultrasonic diagnostic apparatus comprising a seal member mounted on a distal end side of the probe.

In an ultrasonic diagnostic apparatus including a probe inserted into a body cavity of a living body through a trocar, and a main body,
The probe is
An ultrasonic transducer for transmitting and receiving ultrasonic waves,
A plurality of support portions for supporting the ultrasonic vibrator on a support surface, wherein the plurality of support portions are exposed into the body cavity from the insertion end side of the trocar when a probe is inserted into the trocar, and spread apart and spread apart from each other. Diameter, a plurality of support portions facing the ultrasonic oscillator to the ultrasonic irradiation target,
An operation unit extending from the rear end side of the trocar to the outside of the living body when a probe is inserted into the trocar,
A variable mechanism that changes the separation amount of each of the support units according to the operation amount of the operation unit,
With
The main body is
A transmission and reception control unit that controls transmission and reception of the ultrasonic waves,
Based on each output signal of the plurality of ultrasound transducers, an image processing unit that forms a combined ultrasound image,
An ultrasonic diagnostic apparatus comprising:

The ultrasonic diagnostic apparatus according to claim 8,
Each of the support portions is rotatably engaged with a rotation shaft provided at the tip of the probe,
The variable mechanism is to change a separation angle between the support units according to an operation amount of the operation unit,
The ultrasonic diagnostic apparatus, wherein the transmission / reception control unit performs control to deflect the transmission / reception direction of the ultrasonic wave of each ultrasonic transducer toward an insensitive area formed according to the separation angle.

The ultrasonic diagnostic apparatus according to claim 8,
Each of the support portions is rotatably engaged with a rotation shaft provided at the tip of the probe,
The variable mechanism is to change the rotation angle of each of the support units according to the operation amount of the operation unit,
Including an angle sensor for detecting the rotation angle of each of the support portions,
The image processing unit,
Based on each rotation angle detected by the angle sensor, the transmission / reception direction of the ultrasonic wave of each of the ultrasonic transducers is specified, and based on reception signals from a plurality of directions with respect to the same observation position of the ultrasonic irradiation target, the synthesized ultrasonic An ultrasonic diagnostic apparatus for forming an ultrasonic image.