JP4574770B2 - Medical three-dimensional image display device - Google Patents

Description

従ってｆ（ｘ、ｙ、ｚ）を座標変換を行った結果ｆ（ｘ'、ｙ'、ｚ'）を前記（１）式に代入することにより、表示画像は回転する。ここでｎ＝（０，０，１）を考え、これを方向ベクトルとして定義すると、θ＝０，ψ＝０の場合は（２）式を適用しても変化せず、方向ベクトルの投影Ｐ（ｎ）＝（０，１）＝ｎ₀となるため、画像上側を向いていることが明らかである。しかしθ＝３０度、ψ＝３０度の場合、方向ベクトルｎ'＝（√（３）／４、−１／４、√（３）／２）となり、これをＰで平行投影するとＰ（ｎ'）＝（−√（３）／４、√（３）／２）＝ｎ_ｐとなるため、方向ベクトルは表示画像上で傾いてしまっている。これを補正するために投影した方向ベクトルと表示画像上の上方向とのなす角度ηは次のように求められる。
【００３６】
【数２】

ここでは内積演算を示しており、｜ｎ_０｜はベクトルのノルムを表す。ここで求めたηを元に作成した画像を回転させることにより、予め規定された方向ベクトルの方向は、表示画像上で常に上を向いているようになる。但しこのベクトルを通る直線上の１点から観察する場合に限りこの変換は適用できないので、その場合には特にこの変換はその前までの変換を行うこととする。
【００３７】
ここで図1を参照する。図1には本発明の医用三次元画像表示装置による画像表示の一つの例を示している。
【００３８】
図中の（ａ）は初期の観察状態を示しており、頭頂方向１は画面に対して上方向に向いて表示されている。この頭頂方向１に対して血管３、関心領域２が表示されている。操作者は観察方向４の角度から画面を観察しており、この状態において操作者は三次元画像表示における立体的な構造を把握することができる。
【００３９】
この（ａ）の表示状態から操作者が図示しない画像表示操作手段により画像表示を操作する。この場合においては（ｃ）に示すように回転などの操作を行ったとしても、その表示における頭頂方向１は画面の上方向に合致している。このため、操作者は常に頭頂方向１が画面に対して上方向に向いた表示画面を見ることになるので、三次元の立体的な構造の把握が容易に行える。
【００４０】
もちろん、この頭頂方向１を画面の上方向に向けること無く、画像表示操作にしたがって頭頂方向１を画面の上方向に合わせないで表示することもでき、（ｂ）に、その一つの表示例を示す。
【００４１】
また、頭頂方向１の表示方向を画面の上方向以外の所定の方向に向けて表示することもでき、これらの表示の選択を行うための図示しない切替スイッチを設けても良い。
【００４２】
＜実施の形態２＞
図２には本発明の実施の形態２による画像表示の一つの例を示している。
【００４３】
図示しない操作スイッチをオンにすると、観察対象となる血管７などを画像を表示しているフレームにスケール６が表示され、画像横方向はｘｙ面内の回転角を、画像縦方向は頭頂、足尾方向への回転角を示している。この時フレーム内の一点を図示しないマウスのような指示器でカーソル５を移動させて指示すると、その画像座標が取り込まれ、スケール６に従って実際の回転角に変換される。そしてその回転角に表示画像を一度に回転させる。そしてスイッチをオフにすると、スケール６が消え、例えば画像上でマウスを動かすとその移動距離と方向がそれぞれ回転角度と回転方向に変換され、画像の回転が実行される。
【００４４】
本実施の形態２では角度設定を画像の周りに表示したスケール６と画像内の座標によって実施しているが、本発明はこれにとらわれることなく、例えば別のウィンドウにグラフのようなものを表示しても良い。
【００４５】
また、図示しない操作スイッチをオフした後、相対的角度設定を行っているが、絶対的な角度設定を一度行えば、自動的に相対的角度設定に移行しても良い。
【００４６】
＜実施の形態３＞
任意の画像に対する三次元画像表示を表示していない状態で、表示命令を最初に受け取った場合、予め決められた複数方向への投影を作成し、その投影データのエネルギー（各画素の２乗和）を計算する。そしてこのエネルギーの中で最も低い値を示す方向を最初の表示方向として決定する。このようにして、例えば三次元立体表示された血管走向などにおいて、血管同士がもっとも重なり合うことが少ない方向からの画像表示を行うことができる。
【００４７】
＜実施の形態４＞
図３には本発明の実施の形態４における一つの表示例を示している。
【００４８】
医用三次元画像表示装置内に図示しないデータベースを構築し、そのデータベースはある事象に対する一定期間毎（例えば１週間とか１ヶ月、１年等）の観察角度の頻度を保存している。
【００４９】
この事象は例えば患者氏名、患者ＩＤ、症例名、検査時間、検査名、検査医師名、主治医名等の臨床データ１０として記憶されている。これらはあくまで事象の例として挙げられたものであり、それ以外の事象を導入しても良いし、ここに挙げられた事象を全て利用する必要もない。
【００５０】
観察角度は例えば一定間隔毎に設定され、例えば患者の正面から左右５度までで且つ上下５度までは同じ方向としてカウントされる。そして観察角度に対する各事象の頻度に関する関数を定義し（例えば各頻度の和）、その関数を計算し、その中で最も大きな値を示した観察角度を最も望ましい観察角度として決定する。
【００５１】
このようにすれば、過去に（ａ）にて示す三次元血管表示１１を観察していた場合、この図示された方向からの観察頻度が高ければ優先順位が上がってデータベースに記憶される。血管９において認められる関心領域８の表示角度も同時に記憶される。
【００５２】
臨床データ１０に基いて、三次元血管表示１１を後日におこなって血管９の観察をする場合は、（ｂ）に示すように（ａ）における表示角度と同一の角度で表示される。このため両画像データの比較を容易に行うことができ、たとえば（ａ）にて認められた関心領域８が（ｂ）においては消滅している様子を容易に把握できる。
【００５３】
＜実施の形態５＞
表示装置内に例えばニユートラルネットワークのような学習機能のあるアルゴリズムを構築し、このアルゴリズムに対し、例えば実施の形態４に示した事象を信号として与える。そして最終的に望ましい出力（観察角度）が得られた場合は、角度を決定した後、その位置で図示しない決定スイッチを押すことにより、その角度をネットワークにフィードバックして学習させる。最初から最適な画像が得られた場合は、その位置で決定スイッチを押すことにより、ネットワークにこの選択が正しかったことを示す。
【００５４】
なお、実施の形態３乃至５では、観察角度を一意に決定しているが、例えばＦＥＰ（Ｆｒｏｎｔ Ｅｎｄ Ｐｒｏｃｅｓｓｏｒ）の候補表示のように、幾つか可能性の高い順に候補を表示して、そこから操作者が選択できるようにしても良い。
【００５５】
＜実施の形態６＞
原点移動機能をオンにして、表示画像上で注目領域の該中心の１点を指定する。その１点の画像座標を読みとった後、その点を通りｙ軸に平行な直線を求める。その直線上を観察面から三次元画像領域をトレースし、最初に交わった対象表面と次の表面の三次元座標を求め、その中点を新たな原点として設定する。
【００５６】
従って回転、拡大、縮小処理によっては、この原点の表示位置は変化しない。ここでは原点を１回の指定で決定しているが、１回指定した後、観察角度を変化させた時にｙ軸に平行な直線を表示画像上に重ねて表示し、その線上でさらにもう１点指定することにより、最初の指定の時と同じようにもう１つの直線の式が算出され、その交点若しくはその直線が最も近づく点同士の中点を原点としても良い。この方法は手順としては増えるが、原点はこの方が安定して指定できる。
【００５７】
図４にこの表示例を示す。たとえば（ａ）にみられるように原点１４を血管１２および関心領域１２の近傍に設定して、この原点１４を表示操作の原点として行うことで、操作者は容易に三次元立体表示の立体構造を把握することができる。
【００５８】
また、（ｂ）に示すように、原点１４の位置を関心領域１３に設定することで関心領域１３を中心として表示操作を行え、また立体的な構造の把握も容易に行える。
【００５９】
また、原点中心とした回転、拡大、綽小のみについて説明しているが、注目領域のみの表示にも適用できる。原点が指定された後、原点を中心としたある範囲内のみを表示する。この時の表示範囲は、原点を中心とした円や立方体で定義される。円の半径や立方体の辺の長さは、表示画像上に重ねて表示され、そのワイヤーフレーム像のワイヤー部分をたとえばマウスカーソルなどにより引っ張ることにより領域を拡大、縮小することもできる。
【００６０】
以上述べたように、本発明の各実施の形態によれば、被検体の任意の一方向が常に画像上の任意の方向を向いているようにすることで、検査者が三次元構造を理解し易い画像を提供すると同時に、三次元構造を理解し易い方向の個人差に対応するために表示する方向を変更することができる。
【００６１】
また、注目領域の該中心を原点として指定した上で、原点を中心とした表示操作を行うことにより、例えば観察し易い方向を探すための回転処理を行った場合、注目領域を中心とした画像回転を行うため、注目領域は画像上で殆ど移動することなく回転させることができる。
【００６２】
このため観察者は視点を移動することも、また注目領域が画面からはみ出すことも防げ、さらに注目領域以外の領域を表示しないことにより、注目領域に他の部位が重なって観察し難いという事態を回避できる。
【００６３】
また医用の三次元画像では、最初に表示された角度から所望の角度を表示するまでに多くの表示操作を行う必要があったが、三次元画像に関連する臨床情報を基に検査者の期待する初期表示角度を決定することで表示操作を軽減することができる。
【００６４】
さらに表示角度設定手段として指示角度設定手段と任意角度設定手段を有し、まずは指示角度設定手段にて、望ましい観察角度周辺に一度の操作で移動し、そこから任意角度設定手段で最適な角度を細かく変化させながら探すことにより、操作者の省力化が実現できる。
【００６５】
なお、以上説明した実施の形態は、本発明の理解を容易にするために記載されたものであって、本発明を限定するために記載されたものではない。したがって、上記の実施の形態に開示された各要素は、本発明の技術的範囲に属する全ての設計変更や均等物をも含む趣旨である。
【００６６】
【発明の効果】
このように構成された本発明の医用三次元画像表示装置によれば、三次元構造を理解し易い画像を提供することができる
【図面の簡単な説明】
【図１】本発明の実施の形態１における一つの表示例を示す。
【図２】本発明の実施の形態２における一つの表示例を示す。
【図３】本発明の実施の形態４における一つの表示例を示す。
【図４】本発明の実施の形態６における一つの表示例を示す。
【符号の説明】
１…頭頂方向、２…関心領域、３…血管、４…観察方向、５…カーソル、６…スケール、７…血管、８…関心領域、９…血管、１０…臨床データ、１１…三次元血管表示、１２…血管、１３…関心領域、１４…原点[0001]
BACKGROUND OF THE INVENTION
The present invention particularly relates to a display image operation in a medical three-dimensional image display apparatus.
[0002]
[Prior art]
In a conventional medical three-dimensional image display device, rotation about the origin of display coordinates is performed in order to change the viewing direction of a display image. For this reason, for example, the direction of the top of the head may be directed to any direction in the vertical and horizontal directions of the image.
[0003]
Further, in the conventional medical 3D image display device, as an angle setting means for changing the viewing direction of the display image, for example, the displayed 3D image is rotated in the vertical and horizontal directions by moving an input device such as a mouse vertically and horizontally. I am letting. This rotation is a relative angle setting means for determining the change angle based on the moving distance of the mouse. In the medical three-dimensional image display device, the angle displayed first after the three-dimensional display instruction is determined in advance, and most of them display the front direction of the human body.
[0004]
[Problems to be solved by the invention]
Conventionally, however, these medical three-dimensional image display devices have been rotated around the origin in order to change the image viewing direction. For this reason, for example, the direction of the top of the head is directed to all directions of the top, bottom, left, and right of the image by rotation, so it may not be understood which direction the image is facing.
[0005]
This is the same as when viewing a three-dimensional image displayed by a conventional rotation directly on a monitor which is an image display device when tilting the head, for example, toward the top of the head, or observing a printed three-dimensional image. There has been a need to rotate the printed image so that the top of the head faces upward.
[0006]
As described above, the fact that a certain predetermined direction of the subject is always directed to a certain predetermined direction on the image often assists in grasping the three-dimensional structure of the imaged part. Can not. The display direction in which the three-dimensional structure can be easily grasped may vary depending on individual differences among operators.
[0012]
[Means for Solving the Problems]
In order to solve the above problems, in the present invention described in claim 1, a display unit capable of displaying a medical three-dimensional image is provided , and when changing the display direction of the medical three-dimensional image , any subject of the subject is displayed. In the medical three-dimensional image display device defined such that one direction faces a specific direction on the display screen of the display means ,
Specific direction changing means capable of arbitrarily setting and changing the specific direction;
By calculating an angle formed between the direction vector in one arbitrary direction and the direction vector in the specific direction changed by the specific direction changing unit, and rotating the medical three-dimensional image based on the angle, and characterized in that it comprises a display direction defining means for the arbitrary direction of the sample defines the display direction of the display screen of the changed the specific direction they are facing directly as said medical three-dimensional image of the display means A medical three-dimensional image display device is used as a solution.
[0015]
In the present invention described in claim 2, with a medical three-dimensional image display apparatus according to claim 1, characterized in that it comprises the operation select means capable of switching the operation or non-operation of the display direction provisions means Let it be a solution.
[0016]
Further, in the present invention according to claim 3, the arbitrary one direction is a parietal direction, and the solving means includes the medical three-dimensional image display device according to any one of claims 1 and 2. And
[0017]
According to a fourth aspect of the present invention, the medical three-dimensional image is a blood vessel image, and the medical three-dimensional image display device according to any one of claims 1 to 3 provides a solution. And
[0027]
According to the solution means according to the present invention configured as described above, it is easy for the examiner to understand the three-dimensional structure by making any one direction of the subject always face any direction on the image. At the same time as providing an image, the display direction can be changed to cope with individual differences in a direction in which the three-dimensional structure is easily understood.
[0032]
DETAILED DESCRIPTION OF THE INVENTION
In order to facilitate the explanation of the operation of the apparatus, a three-dimensional image is first defined as f (x, y, z). Here, the x axis indicates the right direction of the human body, the y axis indicates the front direction of the human body, and the z axis indicates the top direction of the human body. Similarly, the display image is g (u, v), the u axis is the horizontal axis of the image, and v is the vertical axis of the image. Further, P is expressed as follows as a display image creation process. Here, for easy understanding, P is considered as a parallel projection onto a plane parallel to the xz plane.
[0033]
g (u, v) = P {f (x, y, z)} (1)
Embodiments of the present invention will be described below with reference to the drawings.
[0034]
<Embodiment 1>
Generally, the change of the observation image of the image is configured by coordinate transformation and projection P expressed by the following equation.
[0035]
[Expression 1]

Therefore, the display image is rotated by substituting f (x ′, y ′, z ′) as a result of the coordinate transformation of f (x, y, z) into the equation (1). Here, n = (0, 0, 1) is considered, and this is defined as a direction vector. When θ = 0 and ψ = 0, there is no change even if the expression (2) is applied, and the projection P of the direction vector Since (n) = (0, 1) = n ₀ , it is clear that the image is directed upward. However, when θ = 30 degrees and ψ = 30 degrees, the direction vector n ′ = (√ (3) / 4, −1/4, √ (3) / 2) is obtained. Since ') = (− √ (3) / 4, √ (3) / 2) = _np , the direction vector is inclined on the display image. In order to correct this, an angle η formed by the projected direction vector and the upward direction on the display image is obtained as follows.
[0036]
[Expression 2]

Here, the inner product operation is shown, and | n ₀ | represents the norm of the vector. By rotating the image created based on η obtained here, the direction of the direction vector defined in advance is always directed upward on the display image. However, this conversion cannot be applied only when observing from one point on a straight line passing through this vector. In this case, this conversion is performed up to the previous conversion.
[0037]
Reference is now made to FIG. FIG. 1 shows an example of image display by the medical three-dimensional image display apparatus of the present invention.
[0038]
(A) in the figure shows an initial observation state, and the parietal direction 1 is displayed facing upward with respect to the screen. A blood vessel 3 and a region of interest 2 are displayed with respect to the parietal direction 1. The operator observes the screen from the angle of the observation direction 4, and in this state, the operator can grasp the three-dimensional structure in the three-dimensional image display.
[0039]
From the display state of (a), the operator operates image display by image display operation means (not shown). In this case, even if an operation such as rotation is performed as shown in (c), the parietal direction 1 in the display coincides with the upper direction of the screen. For this reason, since the operator always sees the display screen in which the top direction 1 is directed upward with respect to the screen, the operator can easily grasp the three-dimensional structure.
[0040]
Of course, it is also possible to display the parietal direction 1 without aligning it to the upper direction of the screen in accordance with the image display operation without directing the parietal direction 1 to the upper direction of the screen. Show.
[0041]
Further, the display direction of the parietal direction 1 can be displayed in a predetermined direction other than the upper direction of the screen, and a changeover switch (not shown) for selecting these displays may be provided.
[0042]
<Embodiment 2>
FIG. 2 shows an example of image display according to the second embodiment of the present invention.
[0043]
When an operation switch (not shown) is turned on, the scale 6 is displayed in a frame displaying an image of the blood vessel 7 to be observed, etc., the horizontal direction of the image is the rotation angle in the xy plane, and the vertical direction of the image is the top and the tail The angle of rotation in the direction is shown. At this time, when one point in the frame is indicated by moving the cursor 5 with an indicator such as a mouse (not shown), the image coordinates are taken in and converted into an actual rotation angle according to the scale 6. Then, the display image is rotated at a rotation angle at a time. When the switch is turned off, the scale 6 disappears. For example, when the mouse is moved on the image, the movement distance and direction are converted into the rotation angle and the rotation direction, respectively, and the image is rotated.
[0044]
In the second embodiment, the angle is set by the scale 6 displayed around the image and the coordinates in the image. However, the present invention is not limited to this, and a graph or the like is displayed in another window, for example. You may do it.
[0045]
In addition, the relative angle is set after the operation switch (not shown) is turned off. However, once the absolute angle is set, the relative angle may be automatically set.
[0046]
<Embodiment 3>
When a display command is received for the first time without displaying a 3D image display for an arbitrary image, a projection in a plurality of predetermined directions is created, and the energy of the projection data (the sum of squares of each pixel) ). And the direction which shows the lowest value in this energy is determined as the first display direction. In this way, for example, in the blood vessel strike displayed in a three-dimensional display, it is possible to display an image from the direction in which the blood vessels are least overlapped.
[0047]
<Embodiment 4>
FIG. 3 shows one display example in the fourth embodiment of the present invention.
[0048]
A database (not shown) is constructed in the medical three-dimensional image display device, and the database stores the frequency of observation angles for a certain period (for example, one week, one month, one year, etc.).
[0049]
This event is stored as clinical data 10 such as a patient name, patient ID, case name, examination time, examination name, examining doctor name, and attending doctor name. These are just examples of events, other events may be introduced, and it is not necessary to use all of the events listed here.
[0050]
The observation angle is set, for example, at regular intervals, and is counted as, for example, the same direction from the front of the patient up to 5 degrees to the left and right and up to 5 degrees. Then, a function relating to the frequency of each event with respect to the observation angle is defined (for example, the sum of the frequencies), the function is calculated, and the observation angle showing the largest value among them is determined as the most desirable observation angle.
[0051]
In this way, when the three-dimensional blood vessel display 11 shown in (a) has been observed in the past, if the observation frequency from the illustrated direction is high, the priority is increased and stored in the database. The display angle of the region of interest 8 recognized in the blood vessel 9 is also stored at the same time.
[0052]
When the three-dimensional blood vessel display 11 is performed at a later date based on the clinical data 10 to observe the blood vessel 9, it is displayed at the same angle as the display angle in (a) as shown in (b). For this reason, the comparison of both image data can be performed easily, for example, it can be easily grasped that the region of interest 8 recognized in (a) disappears in (b).
[0053]
<Embodiment 5>
For example, an algorithm having a learning function such as a neutral network is constructed in the display device, and for example, the event shown in the fourth embodiment is given as a signal to the algorithm. When a desired output (observation angle) is finally obtained, the angle is determined, and then a determination switch (not shown) is pressed at that position to feed back the angle to the network for learning. If the optimal image is obtained from the beginning, pressing the decision switch at that position indicates to the network that this selection was correct.
[0054]
In the third to fifth embodiments, the observation angle is uniquely determined. For example, candidates are displayed in order of high possibility, such as FEP (Front End Processor) candidate display. The operator may be able to select.
[0055]
<Embodiment 6>
The origin moving function is turned on and one point at the center of the attention area is designated on the display image. After reading the image coordinates of the one point, a straight line passing through the point and parallel to the y-axis is obtained. A three-dimensional image region is traced on the straight line from the observation surface, and the three-dimensional coordinates of the target surface and the next surface that intersect first are obtained, and the midpoint is set as a new origin.
[0056]
Therefore, the display position of the origin does not change depending on the rotation, enlargement, and reduction processing. Here, the origin is determined by one designation, but after designating once, when the observation angle is changed, a straight line parallel to the y-axis is superimposed on the display image, and another one on the line is displayed. By designating a point, another straight line expression is calculated in the same manner as in the first designation, and the intersection or the midpoint between the closest points of the straight line may be used as the origin. This method increases as a procedure, but the origin can be specified more stably.
[0057]
FIG. 4 shows an example of this display. For example, as shown in (a), the origin 14 is set in the vicinity of the blood vessel 12 and the region of interest 12, and the origin 14 is used as the origin of the display operation. Can be grasped.
[0058]
Also, as shown in (b), by setting the position of the origin 14 to the region of interest 13, display operation can be performed around the region of interest 13 and the three-dimensional structure can be easily grasped.
[0059]
In addition, only rotation, enlargement, and reduction with respect to the origin are described, but the present invention can also be applied to display only the attention area. After the origin is specified, only a certain range centered on the origin is displayed. The display range at this time is defined by a circle or a cube centered on the origin. The radius of the circle and the length of the side of the cube are displayed overlaid on the display image, and the area can be enlarged or reduced by pulling the wire portion of the wire frame image with, for example, a mouse cursor.
[0060]
As described above, according to each embodiment of the present invention, the examiner understands the three-dimensional structure by making an arbitrary direction of the subject always face an arbitrary direction on the image. It is possible to change the display direction in order to cope with individual differences in the direction in which the three-dimensional structure is easy to understand, while providing an easy-to-understand image.
[0061]
In addition, by designating the center of the attention area as the origin and performing a display operation centered on the origin, for example, when performing a rotation process to find a direction that is easy to observe, an image centered on the attention area Since the rotation is performed, the attention area can be rotated with little movement on the image.
[0062]
This prevents the observer from moving the viewpoint and preventing the region of interest from protruding from the screen, and by not displaying the region other than the region of interest, it is difficult to observe because other regions overlap the region of interest. Can be avoided.
[0063]
In medical 3D images, it was necessary to perform many display operations from the first displayed angle until the desired angle was displayed. However, based on clinical information related to 3D images, The display operation can be reduced by determining the initial display angle to be performed.
[0064]
In addition, the display angle setting means includes an instruction angle setting means and an arbitrary angle setting means. First, the instruction angle setting means moves around the desired observation angle by one operation, and from there, the optimum angle is set by the arbitrary angle setting means. By searching while making minute changes, it is possible to save labor for the operator.
[0065]
The embodiment described above is described in order to facilitate understanding of the present invention, and is not described in order to limit the present invention. Therefore, each element disclosed in the above embodiment includes all design changes and equivalents belonging to the technical scope of the present invention.
[0066]
【The invention's effect】
According to medical three-dimensional image display apparatus of the present invention configured as described above, BRIEF DESCRIPTION OF THE DRAWINGS Kyosu Hisage the likely image to understand the three-dimensional structure capable Rukoto
FIG. 1 shows one display example in Embodiment 1 of the present invention.
FIG. 2 shows one display example in Embodiment 2 of the present invention.
FIG. 3 shows one display example in Embodiment 4 of the present invention.
FIG. 4 shows one display example in Embodiment 6 of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Parietal direction, 2 ... Region of interest, 3 ... Blood vessel, 4 ... Observation direction, 5 ... Cursor, 6 ... Scale, 7 ... Blood vessel, 8 ... Region of interest, 9 ... Blood vessel, 10 ... Clinical data, 11 ... Three-dimensional blood vessel Display, 12 ... Blood vessel, 13 ... Region of interest, 14 ... Origin

Claims (4)

A display means capable of displaying a medical 3D image is provided , and when changing the display direction of the medical 3D image, any one direction of the subject seems to be directed to a specific direction on the display screen of the display means In the medical three-dimensional image display device prescribed in
Specific direction changing means capable of arbitrarily setting and changing the specific direction;
By calculating an angle formed between the direction vector in one arbitrary direction and the direction vector in the specific direction changed by the specific direction changing unit, and rotating the medical three-dimensional image based on the angle, and characterized in that it comprises a display direction defining means for the arbitrary direction of the sample defines the display direction of the display screen of the changed the specific direction they are facing directly as said medical three-dimensional image of the display means Medical three-dimensional image display device. Medical three-dimensional image display apparatus according to claim 1, characterized in that it comprises the operation select means capable of switching the operation or non-operation of the display direction provisions means. Wherein any one direction, medical three-dimensional image display apparatus according to any one of claims 1 or 2, characterized in that the top direction. The medical three-dimensional image display device according to any one of claims 1 to 3 , wherein the medical three-dimensional image is a blood vessel image.

Images