Deep penetration beamformed television

• US 6,368,276 B1
• Filed: 11/23/1999
• Issued: 04/09/2002
• Est. Priority Date: 11/23/1999
• Status: Expired due to Fees

• Current Assignee: Bullis, James K.
• Original Assignee: Bullis, James K.
• Inventors: Bullis, James K.
• Primary Examiner(s): Lateef, Marvin M.
• Assistant Examiner(s): Imam, Ali M.
• Application Number:
  US09/448,023
• Time in Patent Office: 868 Days
• Field of Search: 600/437-447, 600/407, 600/425, 600/473, 128/916, 348/128, 348/131, 356/612, 367/7, 367/11, 367/130, 736/20--27
• US Class Current: 600/437
• CPC Class Codes: A61B 8/00 Diagnosis using ultrasonic, sonic or infrasonic waves imaging of objects using sonar G01S15/00
• CPC Class Codes: A61B 8/483 involving the acquisition of a 3D volume of data
• CPC Class Codes: G01S 15/104 wherein the transmitted pulses use a frequency- or phase-modulated carrier wave
• CPC Class Codes: G01S 15/892 the array being curvilinear
• CPC Class Codes: G01S 15/8925 the array being a two-dimensional transducer configuration, i.e. matrix or orthogonal linear arrays
• CPC Class Codes: G01S 7/52026 Extracting wanted echo signals Doppler systems G01S15/50; Doppler short range imaging systems G01S15/8979
• CPC Class Codes: G01S 7/52046 Techniques for image enhancement involving transmitter or receiver image enhancement by image data processing G06T5/00
• CPC Class Codes: G01S 7/5209 using multibeam transmission
• CPC Class Codes: G10K 11/32 characterised by the shape of the source

Abstract

The invention is a new system for deep penetration medical imaging in a comprehensive medical system. Imaging is based on beamformed television methods that utilize orthogonal arrays to image three dimensions with high resolution. The comprehensive medical system is a flexible apparatus that includes detection, diagnostic, and treatment capabilities. Deep penetration operation in attenuating tissue is enhanced by semi-collimated beams which improve signal to noise ratio. The semi-collimated beams improve control of the field of view and simplify signal processing. Embodiments include additional features to enhance deep penetration imaging and make it practical.

Claims

1. A sensing system comprising

(a) two arrays of transducers, where an array is shaped and operated to form a semi-collimated beam segment, and said semi-collimated beam segment defines boundaries of a field of view in one dimension, and

(b) said two arrays are in approximate orthogonal arrangement to define said field of view in two dimensions and to resolve said field of view in two dimensions, and

(c) an array transmits coded signals that radiate through said field of view causing a plurality of coded, semi-collimated, transmit, beam segments to form in transmit regions of said field of view such that said coded signals excite respective said transmit regions, where said transmit regions are at different locations in said field of view, and

(d) objects in said transmit regions cause reflected signals, and

(e) reflected signals are received and processed to form code channels that respond to signals from respective said transmit regions.

2. A sensing system according to claim 1 and signal means to transmit a step chirp signal sequence, and signal means to receive and process reflected step chirp signals to resolve a dimension of said field of view.

3. A sensing system according to claim 1 and signal means to transmit a step chirp signal sequence and to receive and process reflected step chirp signals to resolve a dimension of said field of view, where a transmit event for each step of said step chirp signal sequence radiates a set of said coded signals, and each of said coded signal is a short tone, and signal means to arrange staggered transmission of short tones such that signal arrival times overlap in a sampling window and field of view is restricted.

4. A sensing system according to claim 1 and said coded, semi-collimated transmit, beam segments are pulsed, semi-collimated transmit beam segments, and said pulsed, semi-collimated transmit beam segments are sequential operations, and said code channels are a single channel that sequentially responds to signals from respective said transmit regions.

5. A sensing system according to claim 1 where said two arrays of transducers are formed from a mosaic of transducers that is alternately configured for transmitting and for receiving by operation of electric circuitry.

6. A sensing system according to claim 1 where said coded signals are adjusted in amplitude to compensate for variable attenuation effects.

7. A sensing system according to claim 1 and signal means for gated continuous wave operation, where said coded signals are gated continuous wave coded signals that are staggered in time to cause overlap in a sampling window in each period of a sequence of periods.

8. A sensing system according to claim 1 where said two arrays are transmit arrays and signals from said two arrays interact in human tissue to produce signals that are of frequency that is different from frequency of transmitted signals.

9. A sensing apparatus comprising:

(a) two arrays of transducers where an array is shaped and operated to form a semi-collimated beam segment, and a semi-collimated beam segment defines a field of view in one dimension, and

(b) said two arrays are arranged to define two dimensions of said field of view and to resolve two dimensions of said field of view, and

(c) where an array transmits signals that radiate through said field of view causing a plurality of coded, semi-collimated, transmit, beam segments to form in transmit regions of said field of view such that coded signals excite respective said regions, and reflected signals are received and processed to form code channels that respond to signals from respective said transmit regions, and

(d) signal means to transmit a step chirp signal sequence and to receive and process reflected step chirp signals to resolve a dimension of said field of view.

10. A sensing apparatus according to claim 9 where said two arrays of transducers are formed from a mosaic of transducers that is alternately configured for transmitting and for receiving semi-collimated beams by operation of electric circuitry such that array elements are configured to be uniform strips.

11. A sensing apparatus according to claim 9 where signals of said step chirp signal sequence are short tones, and signal means to process received said step chirp signals to resolve a dimension of said field of view such that field of view is restricted by a gating effect made possible by duration of said short tones.

12. A sensing apparatus according to claim 9 and signal means to vary amplitude of steps of said step chirp signal sequence to compensate for variable attenuation effects.

13. A sensing apparatus according to claim 9 where said two arrays are transmit arrays, and a transducer to receive diagnostic signals where said diagnostic signals have a frequency that is not a frequency of transmitted signals.

14. A sensing apparatus comprising:

(a) two arrays of transducers where an array is shaped and operated to form a beam segment, and said beam segment is focused in one dimension and wide in another dimension, where width of an array is sufficient such that width of said wide beam segment is defined by geometric rules, and

(b) said beam segment defines boundaries of a field of view in one dimension, and

(c) said two arrays are arranged to define boundaries of said field of view and to resolve said field of view in two dimensions, and

(d) signal means to form a plurality of receive beam segments in respective receive regions of said field of view and to form receive beam channels that respond to signals from respective said receive regions.

15. A sensing apparatus according to claim 14 where an array transmits coded signals that radiate through said field of view causing a plurality of coded, transmit, beam segments to form in regions of said field of view such that said coded signals excite respective said regions, and reflected signals are received and processed to form code channels that respond to signals from respective said regions.

16. A sensing apparatus according to claim 14 and signal means to transmit a step chirp signal sequence and to receive and process reflected step chirp signals to resolve a dimension of said field of view.

17. A sensing apparatus according to claim 14 and signal means to resolve a dimension of said field of view utilizing a pulse of short time duration.

18. An imaging system according to claim 14 where said two arrays of transducers are formed from a mosaic of transducers that is alternately configured for transmitting and for receiving by operation of electric circuitry.

19. A sensing apparatus according to claim 14 and harmonic signal processing.

20. A sensing apparatus according to claim 14 and apparatus to manipulate an array.

21. A sensing apparatus according to claim 14 where said semi-collimated beam segment is rectangularly collimated.

22. A sensing apparatus according to claim 14 where said semi-collimated beam segment is cylindrically collimated.

23. A sensing apparatus according to claim 14 and image processing that enables visual format imaging.

24. A sensing apparatus according to claim 14 and signal processing that enables slice format imaging.

25. A sensing apparatus according to claim 14 where elements in an array are sparsely spaced such that grating lobe effects occur and field of view boundaries suppress an effect of reflections from objects outside said field of view.

26. A sensing apparatus according to claim 14 and signal means to resolve a dimension of said field of view utilizing a pulse of short time duration and signal means to pre-distort a pulse to compensate for effects of attenuation.

27. A sensing apparatus according to claim 14 where beam segment formation is accomplished by a combination of shaping a radiating transducer array surface and adjusting time relationships of signals that drive transducer elements.

28. A sensing apparatus according to claim 14 where said arrays overlap.

29. A sensing apparatus according to claim 14 and signal means for gated continuous wave operation.

30. A sensing apparatus according to claim 14 and signal means for gated continuous wave operation and digital storage of coefficients to represent a continuous wave reference signal.

31. A sensing apparatus according to claim 14 and signal means for gated continuous wave operation with capability to discriminate in frequency of reflected signals to sense Doppler shift effects.

32. A sensing apparatus according to claim 14 and capability to acquire a three dimensional block of image signals, and signal means to arrange two dimensional display views that display image signals along arbitrary surfaces.

33. A sensing apparatus according to claim 14 and capability to acquire successive three dimensional blocks of image signals, and signal means to compare said three dimensional blocks to track development of disease.

34. A sensing apparatus according to claim 14 and a device to inject a contrast enhancing substance into a subject of examination.

35. An imaging system according to claim 14 and apparatus to guide surgical instruments.

36. An imaging system according to claim 14 and apparatus to guide injection instruments.