DE2819999C2 - Method and arrangement for the representation of electrical space curves and space images - Google Patents

Description

The invention relates to a method and an arrangement for displaying electrical space curves and spatial images, in particular from electrically reproduced ultrasound images, x-ray images or of vector loops commonly used in cardiology.

It is Z. B. known from cardiology, the cardiac action currents of a test subject each between to represent two electrodes separately and result from the three usual projections of the spatial Curve (frontal, saggital and horizontal) to get an idea of the spatial course of the curve. the Abilities of the people evaluating the various projections to understand the spatial course of the Presenting curves from the individual projections is very different because the clarity is right limited, is.

The invention is therefore based on the object of the course of space curves, be it z. B. off Ultrasound images, X-rays or vector loops in cardiology, completely clear and vivid and watch the space curves from all ropes and from any direction can.

This object is achieved by the method according to the invention in that according to the x-, y- and z-direction in its course over time of the action occurring coordinate streams are kept separate in an electronic memory available that transformed in a first computer x- , y- and z-coordinates of the space curve tilted by any angle λ and rotated by any angle β or of the spatial image of the currents of aclion are calculated and the transformed coordinates x, y and ζ are shown two-dimensionally on the screen of an oscilloscope and by tilting and rotating a spatial imagination is achieved.

According to an advantageous embodiment of the invention, the coordinates x, y and ζ of the space curve tilted by any angle α and rotated by any angle β or of the space image are sent to a second computer for calculating the coordinates of the central projections of the transformed space curve or the space image of two Supplied to eye points in order to display these central projections for each eye point separately in two images of a screen, which are perceived spatially by means of optics. A particular advantage is that the spatial images and spatial curves can be moved manually by setting the angles α and β separately and viewed from any side.

To identify the time sequence and the direction of travel of the spatial curve, time markers are shown in the form of lateral arrows pointing in the direction of the passage, the size of the teeth being dependent on the curve speed.

The arrangement for carrying out the method is characterized in that the electrodes of a test person or a test object are connected to a preamplifier, the outputs of which for the χ, y and z coordinates of the spatial curve via a memory with a first computer for determining the transformed coordinates x, y and ζ for the space curve tilted by an angle α and rotated by an angle β are connected and that the projections of the space curve can be displayed optionally in the planes xy, xzoderyz on the screen of an oscilloscope.

According to a further embodiment of the invention, the_first computer for the transformed coordinates ⁷ , y and ζ is followed by a second computer for determining the central projection coordinates xli. xre and y for two points of view of an observer for the separate display of the two central projections xli, y and xre, / side by side in two images on a screen for stereoscopic viewing by means of suitable optics.

It is advantageous and clear to make the input of the tilt angle α and the rotation angle β by means of associated control elements with a tiltable and rotatable control stick.

According to a special feature, the distance between the eye points and the mean distance is the Visual points from the spatial curve or the spatial image (viewing distance) can be set on the second computer.

The invention will now be based on an exemplary embodiment for the representation of in cardiology usual derivations of electrical action currents (vector loops) explained in detail. It shows

Fig. 1 is a block diagram of the stereokinetic vector cardioscope and

F i g. 2 Details of the time stamp.

From a test person 1 in a known manner bioelectrical signals of the heart activity by means of electrodes placed on the skin, eg. B. by means of the Frank network, derived and fed to a preamplifier 3, which amplifies the signals to a suitable size, e.g. ± 5 V. At the output of the preamplifier 3 are the coordinates of the integral vector loop to x- (from right to left), y- (from bottom to top) and z-direction (from back to front) are available in their time course and are stored in an electronic memory 5, 6, 7 in real time. The memory 5, 6, 7 is controlled by the control part 9 in five ways:

A: Running register

Fill Β- Ι χ

C: read continuously

D: I read χ

E test

At A (running register) the control generates a time axis in the time axis part 11 from η points. In the memory 5, 6, 7, η points are read, and the current data from the preamplifier 3 are stored at the (n + 1) th point. As a result, the memory 5, 6, 7 is completely filled after η has run through the time axis part 11, and it is kept up to date with each further run through the time axis part 11 by deleting the oldest information. If the new storage is omitted at the (n + \) ien point, the information remains fixed in the memory 5,6,7 during the previous η run. Any irregularities in the bioelectrical signals of the test person can thus be recorded and analyzed. At S (fill Ix), the π locations of the memory 5, 6, 7 are filled once with the x, y and z data synchronously with the η points of the z-axis. The filling time is real time.

At C (read continuously) the π memory locations of the memory are read cyclically, and what is read is fed to an oscilloscope 15 via the control part 9 and a line 13 and is displayed on the screen

ίο made visible In order to achieve a never-ending picture, reading takes place 2 ⁵ times faster than filling bites.

At D (I χ read) the η memory locations of the memory 5, 6, 7 are read once, and what is read is fed to an A7> writer 17 via the control part 9 and the line 13 and permanently recorded. In order to adapt to the limited writing speed of the A / y recorder 17, the reading of the memory 5,6,7 2 ⁷ times slower than the filling at B.

With E (test), writing and reading take place alternately in the rhythm of the individual points on the time axis exclusively from place 1 of the memory 5,6,7. Through this two necessary adjustments are possible:

1. Setting the preamplifier 3 to the necessary gain and setting the operating point.

2. Setting the cycle time of the control part 9 in order to match the length of the time axis bring with the cycle to be saved the

jo bioelectrical signals of test subject 1

(R-Zaeken trigger with lead time). To the memory 5, 6, 7 is a registration device 19, for. B. a magnetic tape recorder or a perforated tire puncher connected for documentation in order to be able to save the recorded A, y and z coordinates at any time for the purpose of further analysis. The arrows 21 and 22 drawn in the figure from the memory 5 for the ^ coordinates to the registration device 19 indicate the connection between the memory and the registration device; the memories 6 and 7 for the y and z coordinates are also connected to the recorder in a corresponding manner.

The A, y and z coordinates of the memories 5, 6, 7 are fed to a first computer 28 via lines 24, 25, 26. The time course of these x, y and z coordinates describes a curve in space. The three usual projections of this curve (frontal <= x / y projection; saggital = jVz projection; horizontal = A7z projection) define the spatial course. In order to be able to view the spatial course more clearly from any direction, the first computer 28 is suitable for the parallel projection of the spatial curve defined from x = f (t), y = f (l) and z = f (t) by tilting it around any desired direction Angle <x and turning around any angle β to calculate transformed coordinates a-, y and z. The result of these transformed coordinates is fed to the oscilloscope 15 via the lines 30 to 32 and can be followed immediately on the screen. The angles α and β can be entered very clearly into the first computer 28 (for parallel projection) via a control stick which can be tilted from front to back and vice versa () and rotatable about its axis in both directions (β). The manual movement of the

b5 joystick linked to visual observation of the screen makes it much easier to visualize the spatial curve or the spatial image. Since the space curve to be assessed is a cardiological

Seeing the vector loop is actually located in the thorax of a test subject is for the sake of the Correlation of the button of the control stick formed as a small bust. The sight of the bust in the tilted position and rotated state corresponds to the view of the space curve on the screen in the same state. The frontal, saggilian and horizontal projections can be felt when the control stick clicks into place.

A second computer 34 (for central projection) to which the transformed coordinates x, y and ζ are fed is provided for stereokinetic observation of the spatial curve or the spatial image. This second computer 34 allows the calculation of the coordinates for the central projection of the spatially moving system from two eye points. The visual point distance Aa and the observation distance Ba can be set using two actuators 36, 37. The second computer 34 determines the coordinates xli, xre and ^ ₁ which are used to display two separate images xli / y and xre / y on the oscilloscope screen. These two images are observed with stereoscopic optics, in that the left image (xli / y) is seen by the left eye and the right image (xre / y) is seen by the right eye of the observer, to whom the curve then appears three-dimensional. _

The images xli / y or xre / y can also be written one on top of the other on the x / y writer 17 on paper with green or red ink. Viewing with complementary colored glasses then also allows three-dimensional vision of the paper image (anaglyph method) if the x, y, z system has been rotated or tilted at will.

When viewing the spatial curve on the screen (operating mode C) either in parallel projection or in central projection, the curve is measured by a brightening circuit 39. The beginning of brightening and the duration of brightening can be set and read directly on a 10-turn potentiometer. The lead time is triggered by the beginning of the time axis, while the brightening time is triggered by the end of the lead time. These two times are ^2.5 times faster than real time. The lightening time can also be used as a pen-lift when registering on the x / y recorder 17 in order to only write certain details (e.g. P-loop, possibly on a larger scale). The triggering of the lead time then takes place from the start of operating mode D. The lead time and brightening time must then be switched over to 2 ⁷ times slower than real time.

When registering a projection of the space curve in the two-dimensional paper plane, the following is required:

1. a marking of the time sequence (time stamp) and

2. A recognition of the direction of travel of the curve.

Since the curve is retrieved from memory 5,6,7 and since the memory query can also run backwards in time, the following time and direction marking made:

A curve (Fig. 2) should run continuously from 7 to 15 (queried for example for χ and y from the to memory). _The order 7 - 12, 11, 10, 11, 12 ... 15 is written , 32,42 ...) repeated.

The realization of this course takes place according to the mathematical rule for the Coordinates z. B. from point 10. The coordinates are:

X \ 2 + Ay;) '\ ₂ ± Ax

The upper symbol applies to points on the port side, the lower symbol to points on the starboard ropes of the Curve.

The characteristics of this time stamp are:

1. Curve edge smooth on one side, no interruption of the curve.

2. The size of the time stamps automatically corresponds to the size of the loops written:

- Big loop - big speed -
large Ax or Ay - large point.

- small loop - small speed -
small Ax or Ay- * small point.

The implementation takes place electronically with analog technology using a sample and hold circuit. Using the example of the above point, the following sequence takes place:

Point address counter in SP

sample / hold

Ax, Ay

12 Π

ϊϋ

up

up

up

down

down

up

up

up

up

sample

sample

hold

hold

hold

hold

sample

sample

sample

0 0 0

getting bigger

get smaller

0 0

The x, y are added or subtracted from the current values of x, y as the difference between the values Abhold, yi2hoid.

The intervals between the time stamps (in operation D, read 1 χ) are ²⁷ times slower than real-time (operation mode D). The duration of a timestamp pulse is triggered when a switch is made from hold to sample.

Arbitrary projections according to time (routine derivations): While the vector loop is always written in the x / y-direction of two time-dependent coordinates, with a superimposed time stamp, in practical medicine all derivations used merely represent the projection of the vector loop onto one derivation direction - with time directly as an abcisse, ie only one coordinate in a certain direction is shown. The construction described here makes it possible to derive such arbitrary routine derivations from the vector loop stored in memory 5, 6, 7 by plotting more χ against y , but a direction (which can be determined by turning and tilting) against the time axis ZA.

1 sheet of drawings

Claims (8)

Patent claims: 1. A method for displaying electrical space curves and space images, in particular electrically reproduced ultrasound images, X-ray images or vector loops customary in cardiology, characterized in that the coordinates of the action currents occurring in their time course in an electronic one in the x, y and z directions Memory are kept separately available that_ in a first computer transformed x, y and z coordinates of the space curve tilted by any angle cn and rotated by any angle β or of the spatial image of the streams of action calculated and the transformed coordinates x, y and ζ displayed two-dimensionally on the screen of an oscilloscope and a spatial image is achieved by tilting and rotating. 2. The method according to claim 1, characterized in that the coordinates x, y and ζ of the by any angle a. tilted space curve rotated by any angle β or the space image are fed to a second computer for calculating the coordinates of the central projections of the transformed space curve or the space image of two eye points and that these central projections are shown separately for each eye point in two images on a screen and by means of a Optics are perceived spatially. 3. The method according to claims 1 and 2, characterized in that the spatial images and spatial curves are moved manually by separate setting of the angles m and β and viewed from any side. 4. The method according to claims 1 to 3, characterized in that to identify the temporal The sequence and the passage of the space curve time markers in the form of lateral Arrows pointing in the direction of passage are displayed, with the size of the teeth depends on the cornering speed. 5. Arrangement for carrying out the method according to claim 1, characterized in that the electrodes of a test person or a test object are connected to a preamplifier (3), the outputs of which for the x, y and z coordinates of the spatial curve each have a memory (SP) with a first computer (PP) are connected to the determination of the transformed coordinates x, y and ζ for the space curve tilted by an angle α and rotated by an angle β , and that the Projections of the space curve optionally in the Planes xy, xz or yz can be displayed on the screen of an oscilloscope. 6. Arrangement according to claim 5, characterized in that the first computer (PP) for the transformed coordinates Ar, y and ζ is followed by a second computer (ZP) jsur jirmittlung_der central projection coordinates xli, xre and y for two points of view of an observer for separate display of the two central projections (xli, ~ y) and (xre, ^ side by side in two images on one screen for stereoscopic viewing using suitable optics. 7. Arrangement according to claim 5, characterized in that the input of the tilt angle α and the Verdrehungswi'.ikels β takes place by means of associated control elements by a tiltable and rotatable joystick 8. Arrangement according to claim 6, characterized in that the distance between the eye points from each other and the mean distance of the eye points from the spatial curve or the spatial image (viewing distance) can be set on the second computer.