Apparatus for diagnosing vascular systems in organism

• US 5,357,550 A
• Filed: 09/09/1992
• Issued: 10/18/1994
• Est. Priority Date: 09/09/1991
• Status: Expired due to Term

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Asahina, Hiroshi, Nishiki, Masayuki
• Primary Examiner(s): Church, Craig E.
• Application Number:
  US07/942,272
• Time in Patent Office: 769 Days
• Field of Search: 378/99, 358/111, 128/653.1
• US Class Current: 378/98.5
• CPC Class Codes: A61B 6/481 involving the use of contrast agents
• CPC Class Codes: A61B 6/504 for diagnosis of blood vessels, e.g. by angiography
• CPC Class Codes: A61B 6/5247 combining images from an ionising-radiation diagnostic technique and a non-ionising radiation diagnostic technique, e.g. X-ray and ultrasound
• CPC Class Codes: A61B 8/12 in body cavities or body tracts, e.g. by using catheters catheters per se A61M25/00
• CPC Class Codes: A61B 8/5238 for combining image data of patient, e.g. merging several images from different acquisition modes into one image for image registration algorithms G06T7/30
• CPC Class Codes: G01P 5/001 Full-field flow measurement, e.g. determining flow velocity and direction in a whole region at the same time, flow visualisation
• CPC Class Codes: G01P 5/244 involving pulsed waves
• CPC Class Codes: G16H 30/20 for handling medical images, e.g. DICOM, HL7 or PACS
• CPC Class Codes: G16H 30/40 for processing medical images, e.g. editing
• CPC Class Codes: G16H 40/63 for local operation
• CPC Class Codes: G16H 50/20 for computer-aided diagnosis, e.g. based on medical expert systems
• CPC Class Codes: H05G 1/60 Circuit arrangements for obtaining a series of X-ray photographs or for X-ray cinematography

Abstract

An apparatus is specialized in diagnosing a vascular system in an organism. The diagnostic apparatus is preferable especially to inspection of a circulatory system such as a blood vessel. The inspection can be carried out by obtaining a longitudinal structual image of a lumen of the vascular system and a stenosis index of the lumen. In order to accomplish it, the apparatus comprises an element for fluorographing the vascular system by X-rays, an element for obtaining a plurality of fluoroscopic images based on the X-ray fluoroscopic image signals supplied, an element for ultrasonic probing which has an ultrasonic probe inserted into the vascular system with a catheter, an element for obtaining a plurality of tomographic images based on the ultrasonic tomographic image signals supplied, an element for determining structure of the vascular system based on the plurality of fluoroscopic images and the plurality of tomographic images, and an element for displaying the structure of the vascular system.

Claims

1. An apparatus for diagnosing a vascular system of an organism having a lumen in which an inner wall is formed therein, the vascular system including a blood vessel and the organism having a heart, the apparatus comprising:

means for fluorographing the vascular system to be diagnosed by X-rays, said X-rays being transmitted through the organism and converted into electrical image signals;

means for obtaining, in response to a synchronization signal, fluoroscopic two-dimensional image data in accordance with the image signals supplied by the X-ray fluorographing means;

means for probing the vascular system using ultrasonic signals, the ultrasonic probing means having an ultrasonic probe transferrably inserted into the lumen of the vascular system via a catheter incorporating the ultrasonic probe, the ultrasonic probe being able to obtain ultrasonic echoes representing ultrasonic tomographic images of the vascular system, and the ultrasonic echoes being converted into electrical image signals;

means for obtaining, in response to the synchronization signal, tomographic two-dimensional image data in accordance with the image signals supplied by the ultrasonic probing means;

means for determining a structure of the vascular system in accordance with the fluoroscopic two-dimensional image data and the tomographic two-dimensional image data;

means for displaying the structure of the vascular system;

means for monitoring an electrocardiograph signal representing a cardiac cycle of the heart of the organism; and

means for selecting a timing sequence having a constant interval in each of the cardiac cycles,

wherein each of the fluoroscopic image data obtaining means and the tomographic image data obtaining means comprises means for producing the synchronization signal which is synchronized with said timing sequence while the ultrasonic probe is transferred through the lumen of the vascular system.

2. The apparatus according to claim 1, wherein said structure determining means comprises means for searching transferred positions of the ultrasonic probe transferred through the vascular system for each of the fluoroscopic two-dimensional image data values, means for obtaining section size data of the lumen of the vascular system for each of the tomographic two-dimensional image data values, and means for forming structural data representing the vascular system in accordance with the transferred positions and the section size.

3. The apparatus according to claim 2, wherein said transferred position searching means comprises subtraction means for performing a subtraction pixel-by-pixel between a first fluoroscopic two-dimensional image data value and a subsequent fluoroscopic two-dimensional image data value.

4. The apparatus according to claim 3, wherein said transferred position searching means further comprises a comparison means for comparing subtraction results obtained by the subtraction means with a predetermined threshold level which corresponds to a noise level.

5. The apparatus according to claim 4, wherein said section size data obtaining means comprises an inner wall searching means for searching a position of the inner wall of the vascular system pixel line-by-pixel line for each of the tomographic two-dimensional image data values and a counting means for measuring a section size value of the lumen of the vascular system for each of the tomographic two-dimensional image data values by counting up a total pixel number limited by the inner wall.

6. The apparatus according to claim 3, wherein said structural data forming means comprises a distance calculation means for calculating a transferred distance of the ultrasonic probe transferred through the vascular system in accordance with the transferred positions, a ratio calculating means for calculating a ratio of the section size value between a first tomographic two-dimensional data value and a subsequent tomographic two-dimensional image data value, and a combining means for combining the transferred distance and the ratio into a two-dimensional structural image data value.

7. The apparatus according to claim 3, wherein said section size value is one of a section area and a diameter of the lumen of the vascular system.

8. The apparatus according to claim 7, wherein said combining means comprises means for combining the structural image data in accordance with two axes which are perpendicular to each other, one axis representing the transferred distance in a longitudinal direction of the lumen and the other axis representing the ratio at each position on the transferred position.

9. The apparatus according to claim 8, wherein said structural data forming means further comprises means for calculating a stenosis index of the lumen of the vascular system according to the section size value.

10. The apparatus according to claim 7, wherein said structural data forming means further comprises means for calculating a stenosis index of the lumen of the vascular system according to the section size value.

11. An apparatus for diagnosing a vascular system of an organism having a lumen in which an inner wall is formed therein, the vascular system including a blood vessel, the apparatus comprising:

means for fluorographing the vascular system to be diagnosed by X-rays, said X-rays being transmitted through the organism and converted into electrical image signals;

means for obtaining, in response to a synchronization signal, fluoroscopic two-dimensional image data in accordance with the image signals supplied by the X-ray fluorographing means;

means for probing the vascular system using ultrasonic signals, the ultrasonic probing means having an ultrasonic probe transferrably inserted into the lumen of the vascular system via a catheter incorporating the ultrasonic probe, the ultrasonic probe being able to obtain ultrasonic echoes representing ultrasonic tomographic images of the vascular system, and the ultrasonic echoes being converted to electrical image signals;

means for obtaining, in response to the synchronization signal, tomographic two-dimensional image data in accordance with the image signals supplied by the ultrasonic probing means;

means for determining a structure of the vascular system in accordance with the fluoroscopic two-dimensional image data and the tomographic two-dimensional image data;

first display means for displaying the structure of the vascular system;

first storage means for storing X-ray fluoroscopic image data representing the vascular system, the image data being prepared with contrast medium in accordance with the image signals supplied by the X-ray fluorographing means;

second display means for displaying an X-ray fluoroscopic image as a reference image in accordance with the image data stored in the first storage means;

means for pointing to a desired position along the vascular system shown in the reference image displayed by the second display means;

second storage means for storing transferred positions of the ultrasonic probe, the transferred positions being determined for each sampling period;

means for selecting a tomographic two-dimensional image data value from the tomographic two-dimensional image data values according to the position indicated by the pointing means; and

third display means for displaying the tomographic two-dimensional image data selected by the selecting means.

12. The apparatus according to claim 11, wherein said selecting means comprises means for determining the nearest tomographic two-dimensional image data value when the indicated position differs from each of the transferred positions of the ultrasonic probe.

13. The apparatus according to claim 11, wherein said pointing means comprises means for pointing to a single position as the desired position.

14. The apparatus according to claim 11, wherein said pointing means comprises means for pointing to a plurality of positions as the desired position.

15. The apparatus according to claim 11, wherein said pointing means is one of a light-pen, a touch-screen, a mouse, and a keyboard.

16. The apparatus according to claim 11, wherein each of said fluoroscopic image data obtaining means and said tomographic image data obtaining means comprises means for producing the synchronization signal at each predetermined sampling period while the ultrasonic probe is transferred through the lumen of the vascular system.

17. The apparatus according to claim 16, wherein said structural determining means comprises means for searching transferred positions of the ultrasonic probe transferred through the vascular system for each of the fluoroscopic two-dimensional image data values, means for obtaining section size data of the lumen of the vascular system for each of the tomographic two-dimensional image data values, and means for forming structural data of the vascular system in accordance with the transferred positions and the section size.

18. The apparatus according to claim 17, wherein said transferred position searching means comprises substraction means for performing a substraction pixel-by-pixel between a first fluoroscopic two-dimensional image data value and a subsequent fluoroscopic two-dimensional image data value.

19. The apparatus according to claim 18, wherein said transferred position searching means further comprises comparison means for comparing subtraction results obtained by the subtraction means with a predetermined threshold level which corresponds to a noise level.

20. The apparatus according to claim 17, wherein said section size data obtaining means comprises an inner wall searching means for searching a position of the inner wall of the vascular system pixel line-by-pixel line for each of the tomographic two-dimensional image data values and a counting means for measuring a section size value of the lumen of the vascular system for each of the tomographic two-dimensional image data values by counting up a total pixel number limited by the inner wall.

21. The apparatus according to claim 17, wherein said structural data forming means comprises a distance calculation means for calculating a transferred distance of the ultrasonic probe transferred through the vascular system in accordance with the transferred positions, a ratio calculating means for calculating a ratio of the section size value between a first tomographic two-dimensional image data value and a subsequent tomographic two-dimensional image data value, and a combining means for combining the transferred distance and the ratio into a two-dimensional structural image data value.

22. The apparatus according to claim 21, wherein said section size value is one of a section area and a diameter of the lumen of the vascular system.

23. The apparatus according to claim 22, wherein said combining means comprises means for combining the structural image data in accordance with two axes which are perpendicular to each other, one axis representing the transferred distance in a longitudinal direction of the lumen and the other axis representing the ratio at each position on the transferred distance.

24. The apparatus according to claim 21, wherein said structural data forming means further comprises means for calculating a stenosis index of the lumen of the vascular system according to the section size value.

25. An apparatus for diagnosing a vascular system of an organism having a lumen in which an inner wall is formed therein, the vascular system including a blood vessel, the apparatus comprising:

means for fluorographing the vascular system to be diagnosed by X-rays, said X-rays being transmitted through the organism and converted to electrical image signals;

means for obtaining, in response to a synchronization signal, fluoroscopic two-dimensional image data in accordance with the image signals supplied by the X-ray fluorographing means;

means for probing the vascular system using ultrasonic signals, the ultrasonic probing means comprising an ultrasonic probe transferrably inserted into the lumen of the vascular system via a catheter incorporating the ultrasonic probe, the ultrasonic probe being able to obtain ultrasonic echoes representing ultrasonic tomographic images of the vascular system, and the ultrasonic echoes being converted into electrical image signals;

means for obtaining, in response to the synchronization signal, tomographic two-dimensional image data in accordance with the image signals supplied by the ultrasonic probing means;

means for determining a structure of the vascular system in accordance with the fluoroscopic two-dimensional image data and the tomographic two-dimensional image data; and

means for displaying the structure of the vascular system.

26. The apparatus according to claim 25, wherein each of said fluoroscopic image data obtaining means and said tomographic image data obtaining means comprises means for producing the synchronization signal for each predetermined sampling period while the ultrasonic probe is transferred through the lumen of the vascular system.

27. The apparatus according to claim 26, wherein each of said fluoroscopic image data obtaining means and said tomographic image data obtaining means comprises memory means including a plurality of frame memories for storing the fluoroscopic and tomographic image data.

28. The apparatus according to claim 26, wherein said structure determining means comprises means for searching transferred positions of the ultrasonic probe transferred through the vascular system for each of the fluoroscopic two-dimensional image data values, means for obtaining section size data of the lumen of the vascular system for each of the plurality of tomographic two-dimensional image data values, and means for forming structural data representing the vascular system in accordance with the transferred positions and the section size.

29. The apparatus according to claim 28, wherein said transferred position searching means comprises subtraction means for performing a subtraction pixel-by-pixel between a first fluoroscopic two-dimensional image data value and a subsequent fluoroscopic two-dimensional image data value.

30. The apparatus according to claim 29, wherein said transferred position searching means further comprises comparison means for comparing subtraction results obtained by the subtraction means with a predetermined threshold value which corresponds to a noise level.

31. The apparatus according to claim 28, wherein said section size data obtaining means comprises an inner wall searching means for searching a position of the inner wall of the vascular system pixel line-by-pixel line for each of the tomographic two-dimensional image data values and a counting means for measuring a section size value of the lumen of the vascular system for each of the tomographic two-dimensional image data values by counting up a total pixel number limited by the inner wall.

32. The apparatus according to claim 31, wherein said structural data forming means comprises a distance calculation means for calculating a transferred distance of the ultrasonic probe transferred through the vascular system in accordance with the transferred positions, a ratio calculating means for calculating a ratio of the section size value between a first tomographic two-dimensional image data value and a subsequent tomographic two-dimensional image data value, and a combining means for combining the transferred distance and the ratio into a two-dimensional structural image data value.

33. The apparatus according to claim 32, wherein said section size value is one of a section area and a diameter of the lumen of the vascular system.

45. The apparatus according to claim 26, wherein said X-ray fluorographing means comprises an X-ray source irradiating the X-rays, an image intensifier converting the X-rays transmitted through the organism to fluorescent lights, and an X-ray TV camera converting the fluorescent lights to the electrical image signals.

46. The apparatus according to claim 32, wherein said combining means comprises means for combining the structural image data in accordance with two axes which are perpendicular to each other, one axis representing the transferred distance in a longitudinal direction of the lumen and the other axis representing the ratio at each position on the transferred distance.

47. The apparatus according to claim 31, wherein said structural data forming means further comprises means for calculating a stenosis index of the lumen of the vascular system in accordance with the section size value.

48. The apparatus according to claim 47, wherein said stenosis calculating means comprises means for determining a maximum value of the section size value as a non-illness portion of the vascular system and a minimum value of the section size value as an illness portion of the vascular system.

49. The apparatus according to claim 48, wherein said stenosis calculating means comprises means for calculating at least one of an index representing the stenosis with respect to a cross-sectional area of the lumen and an index representing the stenosis with respect to a diameter of the lumen.

50. The apparatus according to claim 47, wherein said structure displaying means has a mechanism displaying said stenosis index together with said structural image.

51. The apparatus according to claim 50, wherein said structure displaying means comprises a further mechanism displaying said fluoroscopic image obtained by said fluoroscopic image obtaining means.

34. An apparatus for diagnosing a vascular system of an organism having a lumen in which an inner wall is formed therein, the vascular system including a blood vessel, the apparatus comprising:

means for fluorographing the vascular system to be diagnosed by X-rays, said X-rays being transmitted through the organism and converted into electrical image signals;

means for obtaining, in response to a synchronization signal, fluoroscopic two-dimensional image data in accordance with the image signals supplied by the X-ray fluorographing means;

means for probing the vascular system using ultrasonic signals, the ultrasonic probing means having an ultrasonic probe transferrably inserted into the lumen of the vascular system via a catheter incorporating the ultrasonic probe, the ultrasonic probe being able to obtain ultrasonic echoes representing ultrasonic tomographic images of the vascular system, and the ultrasonic echoes being converted into electrical image signals;

means for obtaining, in response to the synchronization signal, tomographic two-dimensional image data in accordance with the image signals supplied by the ultrasonic probing means;

means for determining a structure of the vascular system in accordance with the fluoroscopic two-dimensional image data and the tomographic two-dimensional image data;

means for designating a diameter of the ultrasonic probe;

means for calculating an absolute cross-sectional area of the lumen and an absolute diameter of the lumen in accordance with data corresponding to the structure of the vascular system and the diameter of the ultrasonic probe; and

means for displaying the structure of the vascular system together with the absolute cross-sectional area of the lumen and the absolute diameter of the lumen.

35. The apparatus according to claim 34, wherein said absolute cross-sectional area and diameter calculating means comprise means for calculating a section area per pixel in accordance with the diameter of the ultrasonic probe and further comprise means for calculating the absolute cross-sectional area of the lumen and the absolute diameter of the lumen using the sectional area per pixel.

36. The apparatus according to claim 35, wherein each of said fluoroscopic image data obtaining means and said tomographic image data obtaining means comprises means for producing the synchronization signal for each predetermined sample period while the ultrasonic probe is transferred through the lumen of the vascular system.

37. The apparatus according to claim 36, wherein said structure determining means comprises means for searching transferred positions of the ultrasonic probe transferred through the vascular system for each of the fluoroscopic two-dimensional image data values, means for obtaining section size data of the lumen of the vascular system for each of the tomographic two-dimensional image data values, and means for forming structural data representing the vascular system in accordance with the transferred positions and the section size.

38. The apparatus according to claim 37, wherein said transferred position searching means comprises subtraction means for performing a subtraction pixel-by-pixel between a first fluoroscopic two-dimensional image data value and a subsequent fluoroscopic two-dimensional image data value.

39. The apparatus according to claim 38, wherein said transferred position searching means further comprises a comparison means for comparing subtraction results obtained by the substraction means with a predetermined threshold level which corresponds to a noise level.

40. The apparatus according to claim 37, wherein said section size data obtaining means comprises an inner wall searching means for searching a position of the inner wall of the vascular system pixel line-by-pixel line for each of the tomographic two-dimensional image data values and a counting means for measuring a section size value of the lumen of the vascular system for each of the tomographic two-dimensional image data values by counting up a total pixel number limited by the inner wall.

41. The apparatus according to claim 37, wherein said structural data forming means comprises a distance calculation means for calculating a transferred distance of the ultrasonic probe transferred through the vascular system in accordance with the transferred positions, a ratio calculating means for calculating a ratio of the section size value between a first tomographic two-dimensional image data value and a subsequent tomographic two-dimensional image data value, and a combining means for combining the transferred distance and the ratio into a two-dimensional structural image data value.

42. The apparatus according to claim 41, wherein said section size value is one of a section area and a diameter of the lumen of the vascular system.

43. The apparatus according to claim 42, wherein said combining means comprises means for combining the structural image data in accordance with two axes perpendicular to each other, one axis representing the transferred distance in a longitudinal direction of the lumen and the other axis representing the ratio at each position on the transferred distance.

44. The apparatus according to claim 41, wherein said structural data forming means further comprises means for calculating a stenosis index of the lumen of the vascular system in accordance with the section size value.