Ultrasound system for cerebral blood flow imaging and microbubble-enhanced blood clot lysis

• US 10,363,012 B2
• Filed: 03/24/2017
• Issued: 07/30/2019
• Est. Priority Date: 08/11/2006
• Status: Active Grant

• Current Assignee: Koninklijke Philips N.V.
• Original Assignee: Koninklijke Philips N.V.
• Inventors: Browning, Theodore J., Shi, William, Powers, Jeffry E., Averkiou, Michalakis, Gauthier, Thomas
• Primary Examiner(s): Hoffa, Angela M
• Application Number:
  US15/468,256
• Publication Number:
  US 20170196465A1
• Time in Patent Office: 858 Days
• CPC Class Codes: A61B 17/22004 using mechanical vibrations, e.g. ultrasonic shock waves A61B17/225 takes precedence
• CPC Class Codes: A61B 2017/22014 the ultrasound transducer being outside patient's body; with an ultrasound transmission member; with a wave guide; with a vibrated guide wire not applied in A61B17/22012
• CPC Class Codes: A61B 2090/502 Headgear, e.g. helmet, spectacles
• CPC Class Codes: A61B 5/02007 Evaluating blood vessel condition, e.g. elasticity, compliance
• CPC Class Codes: A61B 5/6814 Head
• CPC Class Codes: A61B 8/06 Measuring blood flow measuring volume flow in general G01F, e.g. G01F1/66, G01F1/72; measuring speed of fluids in general G01P5/00
• CPC Class Codes: A61B 8/08 Detecting organic movements or changes, e.g. tumours, cysts, swellings A61B8/02 - A61B8/06 take precedence
• CPC Class Codes: A61B 8/0808 for diagnosis of the brain
• CPC Class Codes: A61B 8/0816 using echo-encephalography
• CPC Class Codes: A61B 8/085 for locating body or organic structures, e.g. tumours, calculi, blood vessels, nodules
• CPC Class Codes: A61B 8/13 Tomography A61B8/10, A61B8/12 take precedence; tomography for radiation diagnosis A61B6/02
• CPC Class Codes: A61B 8/4227 characterised by straps, belts, cuffs or braces
• CPC Class Codes: A61B 8/4281 characterised by sound-transmitting media or devices for coupling the transducer to the tissue
• CPC Class Codes: A61B 8/481 involving the use of contrast agent, e.g. microbubbles introduced into the bloodstream analysis of echo signal exploiting properties of a contrast enhancer in devices for short-range imaging with acoustic waves G01S7/52039
• CPC Class Codes: A61B 8/483 involving the acquisition of a 3D volume of data
• CPC Class Codes: A61B 8/488 involving Doppler signals
• CPC Class Codes: A61N 2007/0021 Neural system treatment
• CPC Class Codes: A61N 2007/0039 using microbubbles
• CPC Class Codes: A61N 2007/0078 with multiple treatment transducers
• CPC Class Codes: A61N 2007/0082 Scanning transducers
• CPC Class Codes: A61N 2007/0095 : by modifying an excitation signal
• CPC Class Codes: A61N 7/00 : Ultrasound therapy lithotripsy A61B17/22, A61B17/225; massage using supersonic vibration A61H23/00 ; using ultrasound for introducing media into the body A61M37/0092
• CPC Class Codes: G01S 15/8981 : Discriminating between fixed and moving objects or between objects moving at different speeds, e.g. wall clutter filter
• CPC Class Codes: G01S 7/52041 : detecting modification of a contrast enhancer, e.g. detecting the destruction of a contrast agent by an acoustic wave, e.g. loss of correlation diagnostic techniques involving the use of contrast agents A61B8/481

Abstract

An ultrasonic diagnostic imaging system is described which utilizes one or more transducer arrays affixed to the head of a patient to diagnose and treat stroke victims. The transducer headset produces a two or three dimensional image of the vasculature inside the cranium, preferably assisted by a microbubble contrast agent. A vascular flow map is produced by the system which may be diagnosed for signs of a blood clot. If a blood clot is detected, a therapeutic beam is transmitted while the contrast agent is present to break up the blood clot by the disruption of microbubbles. The headset may also be used in a monitoring application to detect the recurrence of blood clots in a stroke victim.

Claims

1. A stroke therapy system for treating a cranial vascular obstruction comprising:

a transducer array headset adapted to maintain a first transducer array and a second ultrasonic transducer array,

wherein both the first transducer array and the second transducer array are in acoustic contact with a head of a subject,

wherein the first transducer array and the second transducer array are configured to transmit respective a first imaging beam and a second imaging beam to obtain imaging data of blood flow in the head of the subject;

an image processor coupled to the first transducer array and the second transducer array,

wherein the processor is configured to produce a first image and a second image from the imaging data of blood flow in the head of the subject of the respective first transducer array and the second transducer array,

wherein the first imaging beam and the second imaging beam are configured to obtain image data of a same region of the head from different sides of the head,

wherein the image processor is further configured to generate a fused image of the same region based on the image data from the first imaging beam and the second imaging beam;

an image display coupled to the image processor and configured to, responsive to user control, display at least one of the first image and the second image from the imaging data of blood flow in the head of the subject, and the fused image; and

a transmitter coupled to the first transducer array and the second transducer array and wherein the transmitter is configured to cause one or more of the first and the second transducer arrays to transmit a therapeutic beam and the first imaging beam and the second imaging beam over an image field, the first imaging beam and the second imaging beam exhibiting a first dimension in the head, and the therapeutic beam exhibiting a second dimension in the head,

wherein the second dimension of the therapeutic beam is less than the first dimension of the first imaging beam and the second imaging beam,

wherein the therapeutic beam is directed to a site of the cranial vascular obstruction and configured to treat the cranial vascular obstruction.

2. The stroke therapy system of claim 1, wherein the image processor comprises a Doppler processor,

wherein the Doppler processor is configured to produce at least one of colorflow Doppler images or power Doppler images.

3. The stroke therapy system of claim 1, wherein the therapeutic beam comprises an ultrasonic beam which is configured to disrupt microbubbles at the site of the cranial vascular obstruction.

4. The stroke therapy system of claim 1, wherein the transmitter is configured to cause the one or more of the first transducer array and the second transducer array to transmit a therapeutic beam within the limits for diagnostic ultrasound energy delivery to the subject.

5. The stroke therapy system of claim 1, wherein the transmitter is configured to apply at least one of pulse width modulated or duty cycle modulated signals to the first transducer array and the second transducer array.

6. The stroke therapy system of claim 1, wherein the transmitter is configured to cause the first transducer array and the second transducer array to transmit beams for at least one of Doppler or B mode imaging.

7. The stroke therapy system of claim 6, wherein the transmitter is configured to transmit imaging beams over an image field occupying a first spatial region in the head,

wherein the therapeutic beam is transmitted over a portion of the first spatial region.

8. The stroke therapy system of claim 7, wherein the first transducer array and the second transducer array each comprise a two dimensional array of transducer elements,

wherein the first spatial region is a volumetric region.

9. The stroke therapy system of claim 8, wherein the transducer array headset is configured to maintain the first two dimensional array in acoustic contact with one side of the head and the second two dimensional array in acoustic contact with the other side of the head.

10. The stroke therapy system of claim 9, wherein the first two dimensional array is configured to scan imaging beams over a majority of a cranial distance between the left side of the head and the center of the head;

and

wherein the second two dimensional array is configured to scan imaging beams over a majority of the cranial distance between the right side of the head and the center of the head.

11. A method for treating stroke comprising:

applying a headset containing first transducer array and the second transducer array to a head of a subject with the transducer arrays in acoustic contact with opposite sides of the head;

securing the headset to maintain the first transducer array and the seconds transducer array in acoustic contact with the head;

infusing the blood stream of the subject with microbubbles;

producing, based on an imaging ultrasound beam comprising a first dimension, a first ultrasound image and a second ultrasound image of cranial flow containing microbubbles using signals received from the first transducer array and the second of the transducer array, respectively;

detecting a stenosis by comparing the relative symmetry of the first ultrasound image and the second ultrasound image and locating an asymmetry; and

directing, to the microbubbles from at least one of the transducer arrays, a therapeutic ultrasound beam comprising a second dimension,

wherein the second dimension of the therapeutic beam is less than the first dimension of the imaging beam such that the therapeutic ultrasound beam is configured to dissolve a blood clot at the site of the stenosis.

12. The method of claim 11 wherein directing the therapeutic beam further comprises steering a pencil beam to microbubbles proximal to the stenosis.

13. The method of claim 11 wherein directing the therapeutic beam further comprises vibrating microbubbles proximal to the stenosis.

14. The method of claim 11 wherein directing the therapeutic beam further comprises breaking microbubbles proximal to the stenosis.

15. The method of claim 11, wherein directing the therapeutic ultrasound beam further comprises transmitting a therapeutic ultrasound beam to microbubbles proximal to the stenosis at an energy level which is within the limits for diagnostic ultrasound.

16. The method of claim 11, wherein applying the headset containing first transducer array and second transducer array comprises applying the headset containing a first two dimensional transducer array and a second two dimensional transducer array,

wherein producing the first ultrasound image and the second ultrasound image further comprises producing a first three dimensional ultrasound image and a second three dimensional ultrasound image.

17. The method of claim 11, further comprising producing, before infusing the blood stream of the subject with the microbubbles, the first and the second ultrasound images of the cranial flow from signals received from at least one of the first transducer array or the second transducer array.