Procedure for an examination of objects by the means of ultrasound waves

Abstract

The invention describes a procedure for the examination of objects by the means of ultrasound waves whereby a volume-of-interest is scanned by a 3D-ultrasound-probe by moving a transmitter/receiver beam in a scan plane within selectable limits. This B-mode scan plane is also simultaneously moved in a direction across to this scan plane. The transmitting of sound pulses and acquiring the echo-signals is done more or less continuously during the movement in B-plane and across to it The echo-signals are stored in a volume memory on addresses which correspond to the spatial position of the echo-generating structure inside the object. These stored data-sets are evaluated by a 3D-processor and are represented on at least one display unit by different algorithms with selectable parameters. Important is that the acquisition and the representation is done continuously.

1. A method of examining an object by means of ultrasound waves, which comprises the steps of
 (a) scanning a volume of the object by the ultrasound waves emitted from a 3D-ultrasound probe designed to produce a B-mode image during the scanning while maintaining the probe stationary, 
 (b) moving a scanning plane in a transmitter/receiver unit in the stationary probe across the volume transversely to the scanning plane,
 (1) a volume-of-interest being selected by setting limits for the path of movement of the scanning plane, 
 
 (c) at least substantially continuously scanning the volume-of-interest by echo pulses generated and processed during the movement of the scanning plane, 
 (d) storing signals generated by the echo pulses in a correct position corresponding to the geometric location of the origin of the signals, 
 (e) evaluating the stored signals by a 3D-processor to produce the B-mode image, and 
 (f) displaying the image on a display unit. 
 
     
     
       2. The method of  claim 1 , wherein the transmitter/receiver unit is reciprocatingly moved in a forward and return movement across the volume, the signals during the return movement being generated at least close to the scanning traces during the forward movement. 
     
     
       3. The method of  claim 2 , wherein the series of echo pulses during the forward movement is reversed during the return movement whereby the B-mode image has the same spatial position during the return movement as during the forward movement. 
     
     
       4. The method of  claim 1 , wherein the signals are stored in a vector-oriented volume memory. 
     
     
       5. The method of  claim 1 , selectively matched to the object by a parameter selected from the group consisting of adjusting the scanning angle of the B-mode image, the swivelling angle for the volume scanning, the number of echo pulses forming the B-mode image, the sweeping speed of the canning, the maximum depth of the echo pulses, and the arbitrary plane from which the volume is illuminated. 
     
     
       6. The method of  claim 1 , comprising the further step of interpolating on the display unit between at least two sequentially produced images. 
     
     
       7. A method of examining an object, comprising:
 defining a scanning plane of a transmitter/receiver unit in a 3D-ultrasound probe:   continuously scanning a volume of the object with ultrasound waves emitted from the 3D-ultrasound probe to produce echo signals representative of multiple scans of the volume; and   moving the scanning plane of the transmitter/receiver unit transversely across the volume continuously, during the multiple scans while maintaining the 3D-ultrasound probe stationary with respect to the volume.   
     
     
       8. The method of claim 7, further comprising displaying at least first and second images associated with corresponding at least first and second scans of the volume based on echo signals generated while continuously scanning the volume. 
     
     
       9. The method of claim 7, wherein the ultrasound waves emitted from the 3D-ultrasound probe produce echo signals representative of a B-mode image. 
     
     
       10. The method of claim 7, wherein said moving step moves the scanning plane in forward and return directions transverse to the scanning plane to continuously scan the volume. 
     
     
       11. The method of claim 7, further comprising processing the echo signals during movement of the scanning plane in forward and return directions. 
     
     
       12. The method of claim 7, further comprising storing echo signals produced in response to the ultrasound waves emitted by the 3D-ultrasound probe, said echo signals being stored at memory locations corresponding to geometric locations in the volume, at which associated echo signals originated. 
     
     
       13. The method of claim 7, further comprising evaluating echo signals by a 3D-processor, said echo signals being generated in response to the ultrasound waves. 
     
     
       14. The method of claim 7, wherein said moving step further comprises reciprocatingly moving the transmitter/receiver unit in forward and return directions across the volume and receiving echo signals during movement of the transmitter/receiver unit in both of the forward and return directions. 
     
     
       15. The method of claim 7, further comprising reconstructing the echo signals in an arbitrary plane of the volume. 
     
     
       16. The method of claim 7, further comprising visualizing the echo signals in an arbitrary plane of the volume, the arbitrary plane being independent of a position and direction of the scanning plane of the transmitter/receiver unit. 
     
     
       17. The method of claim 7, further comprising visualizing movement, within the volume, of the object. 
     
     
       18. The method of claim 7, wherein said scanning, defining and moving steps are carried out continuously at a volume rate sufficiently high to visualize movement, within the volume, of the object on a display. 
     
     
       19. The method of claim 7, further comprising:
 selecting range limits for a range of the volume over which the scanning plane is moved, said range being less than a full size of the volume; and   limiting movement of the scanning plane to remain within said range limits.   
     
     
       20. The method of claim 7, further comprising:
 selecting size limits for a size of the scanning plane; and   limiting the size of the scanning plane to remain within said size limits.   
     
     
       21. The method of claim 7, wherein the volume is defined by outer size limits of the scanning plane and outer range limits of the movement of the scanning plane, further comprising limiting at least one of the defining, scanning and moving steps to a limited volume of interest smaller than at least one of said outer size and range limits. 
     
     
       22. The method of claim 7, wherein said moving step mechanically moves the transmitter/receiver unit within the 3D-ultrasound probe while the 3D-ultrasound probe remains stationary with respect to the volume. 
     
     
       23. The method of claim 7, wherein said moving step electronically moves the scanning plane while the transmitter/receiver unit and 3D-ultrasound probe remain stationary with respect to the volume. 
     
     
       24. The method of claim 7, wherein said moving step includes forward and return movement said method further comprising:
 generating scan lines during forward movement of the scanning plane at a first set of locations in the volume; and   generating scan lines during return movement of the scanning plane at a second set of locations in the volume, the first and second sets of locations being close to one another.   
     
     
       25. The method of claim 7, further comprising adjusting a size of the volume scanned by adjusting at least one of an angle of the scanning plane with respect to the volume, a swivel angle of the scan plane with respect to the volume, a number of echo pulses used to form each scan, a sweep speed of the scanning plane, a maximum depth of echo pulses within the volume and an arbitrary plane from the volume to be displayed. 
     
     
       26. The method of claim 7, further comprising storing the echo signals in a vector-oriented memory at locations corresponding to points in the volume at which the echo signals originate.