Patent Description:
The documents <CIT>, <CIT>, <CIT> and <CIT> represent the technological background of the invention.

Ultrasound imaging, also known as sonography, is a medical imaging technique that employs high-frequency sound waves to view three-dimensional structures inside the body of a living being. Because ultrasound images are captured in real-time, ultrasound images also show movement of the the internal organs of the body as well as blood flowing through the blood vessels of the human body and the stiffness of tissue. Unlike x-ray imaging, ultrasound imaging does not involve ionizing radiation thereby allowing prolonged usage of ultrasound imaging without threatening tissue and internal organ damage from prolonged radiation exposure.

To acquire ultrasound imagery, during an ultrasound exam, a transducer, commonly referred to as a probe, is placed directly on the skin or inside a body opening. A thin layer of gel is applied to the skin so that the ultrasound waves are transmitted from the transducer through the medium of the gel into the body. The ultrasound image is produced based upon a measurement of the reflection of the ultrasound waves off the body structures. The strength of the ultrasound signal, measured as the amplitude of the detected sound wave reflection, and the time taken for the sound wave to travel through the body provide the information necessary to compute an image.

Compared to other prominent methods of medical imaging, ultrasound presents several advantages to the diagnostician and patient. First and foremost, ultrasound imaging provides images in real-time. As well, ultrasound imaging requires equipment that is portable and can be brought to the bedside of the patient. Further, as a practical matter, the ultrasound imaging equipment is substantially lower in cost than other medical imaging equipment, and as noted, does not use harmful ionizing radiation. Even still, the production of quality ultrasound images remains highly dependent upon a skilled operator.

In this regard, depending upon the portion of the body selected for imaging, the skilled operator must know where to initially place the ultrasound probe. Then, the skilled operator must know how to spatially orient the probe and finally, the skilled operator must know where to move the probe so as to acquire the desired imagery. Generally, the ultrasound operator is guided in the initial placement, orientation and movement of the probe based upon the visual feedback provided by the imagery produced during the ultrasound. Thus, essentially, the navigation of the probe is a manual process consisting of iterative trial and error. Plainly, then, the modern process of ultrasound navigation is not optimal.

Embodiments of the present invention address deficiencies of the art in respect to ultrasound probe navigation and provide a novel and non-obvious method, system and computer program product for the guided navigation of an ultrasound probe. In an embodiment of the invention, an ultrasound navigation assistance method according to claim <NUM> is disclosed.

In another embodiment of the invention, an ultrasound imaging data processing system according to claim <NUM> is disclosed.

Additional aspects of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The aspects of the invention will be realized and attained by means of the elements and combinations particularly pointed out in the appended claims.

The accompanying drawings, which are incorporated in and constitute part of this specification, illustrate embodiments of the invention and together with the description, serve to explain the principles of the invention. The embodiments illustrated herein are presently preferred, it being understood, however, that the invention is not limited to the precise arrangements and instrumentalities shown, wherein:.

Embodiments of the invention provide for guided navigation of an ultrasound probe. In accordance with an embodiment of the invention, an ultrasound probe is placed on the surface of a body. Then, imagery of a target organ of the body is acquired and a deviation of a contemporaneous pose of the ultrasound pose evident from the acquired image from an optimal pose for the target organ is presented to an end user operator of the ultrasound probe. For example, the deviation is presented visually in respect to a corresponding display, audibly by way of an audible guidance signal, or in the alterative, by way of the text to speech presentation of textual instructions, or haptically through the outer shell of the ultrasound probe.

In illustration, <FIG> is a pictorial illustration of a process for guided navigation of an ultrasound probe. As shown in <FIG>, an ultrasound probe <NUM> is placed upon an outer surface of a body <NUM> such as a human form. Imagery <NUM> of a target organ is acquired by the operator of the ultrasound probe <NUM> and the image <NUM> of the target organ is presented input to an estimator <NUM>, such as a neural network. The estimator <NUM> is trained based upon a set of training images <NUM> of one or more different target organs, each with a known probe pose deviation from the optimal probe pose so that the input of the contemporaneously acquired image <NUM> to the estimator <NUM> produces an output of a deviation <NUM> of the contemporaneous pose of the ultrasound probe <NUM> from an optimal pose of the ultrasound probe <NUM>.

Optionally, the ultrasound probe <NUM> acquires probe orientation and movement data <NUM> including magnetomic information 180A, gyroscopic information 180B and accelerometric information 180C indicating an orientation and movement of the ultrasound probe <NUM> so as to compute the change in the pose of the ultrasound probe <NUM>. Guided navigation logic <NUM> then processes the probe orientation and movement data <NUM> so as to better compute the deviation from the optimal pose <NUM> in consideration not only of the pose deviation <NUM> output by the estimator <NUM> in respect to the acquired image <NUM> but also in consideration of the change in the pose of the ultrasound probe <NUM> determined from the probe orientation and movement data <NUM>.

Guided navigation logic <NUM> then processes the pose deviation <NUM> of the ultrasound probe <NUM> and emits feedback <NUM> in the form of visual feedback such as a three-dimensionally rendered scene with the two probe models showing current and optimal probe poses with suggested maneuver; the amount of agreement between the current and optimal poses; or red, green or yellow colors indicating how large an adjustment of the orientation of the ultrasound probe <NUM> is required to approach the optimal pose, audible feedback such as a tone, or haptic feedback. In regard to the latter, in one aspect of the invention the ultrasound probe <NUM> may be caused to vibrate more intensely or with greater frequency responsive to the pose deviation <NUM>.

In respect to the former, in one aspect of the invention the ultrasound probe <NUM> may be caused to emit a sound that is more intense of a different tone when the ultrasound probe <NUM> based upon the magnitude of the pose deviation <NUM>. As well the ultrasound probe <NUM> may be caused to emit a short-duration sound such as a click or pop repeatedly with a frequency related to the magnitude of the pose deviation <NUM>. Alternatively, in another aspect of the invention the ultrasound probe <NUM> may be caused to vibrate more intensely or with greater frequency when the ultrasound probe <NUM> is moved in a compliant manner based upon a magnitude of the pose deviation <NUM>.

The process described in connection with <FIG> may be implemented in an ultrasound data processing system. In further illustration, <FIG> schematically illustrates an ultrasound data processing system configured for guided navigation of an ultrasound probe. The system includes an ultrasound probe <NUM> coupled to a host computing system <NUM> of one or more computers, each with memory and at least one processor. The ultrasound probe <NUM> is enabled to acquire ultrasound imagery by way of a transducer connected to beamformer circuitry in the host computing system <NUM>, and transmit the acquired ultrasound imagery to the beamformer circuitry of the host computing system <NUM> for display in a display of the host computing system <NUM> through an ultrasound user interface <NUM> provided in the memory of the host computing system <NUM>.

The ultrasound probe <NUM> includes an electromechanical vibration generator <NUM> such as a piezo actuator, and a tone generator <NUM>. The electromechanical vibration generator <NUM> may be driven in the ultrasound probe <NUM> to cause the ultrasound probe <NUM> to vibrate at a specific frequency and for a specific duration as directed by the host computing system <NUM>. As well, the tone generator <NUM> may be driven in the ultrasound probe <NUM> to cause the ultrasound probe <NUM> to emit an audible tone at a specific frequency and amplitude and for a specific duration as directed by the host computing system <NUM>. Optionally, the tone generator <NUM> may be disposed in the host computing system <NUM>.

An image data store <NUM> stores therein a multiplicity of different ultrasound images previously acquired in a controlled setting where the pose deviation of each image is known. The images of the image store <NUM> are provided as training images in training an estimator <NUM> such as a neural network providing decisioning of a deviation from an optimal probe pose relative to an input image of a target organ of a human form. In this regard, the estimator <NUM> includes a multiplicity of nodes processing different extracted features of an acquired image so as to decision a pose of the ultrasound probe providing a deviation of the decisioned pose from a known, optimal pose in imaging a target organ. In this regard, the pose can be represented mathematically in Euclidian space or any array of numbers.

Finally, a navigation assistance module <NUM> is coupled to the ultrasound user interface <NUM>. The navigation assistance module <NUM> includes program code that when executed in the memory of the host computing system <NUM> acquires a contemporaneous ultrasound image by the ultrasound probe <NUM> and processes the acquired ultrasound image in the host computing platform <NUM> utilizing the estimator <NUM>. The program code of the navigation assistance module <NUM> during execution in the memory of the host computing system <NUM> then receives with the assistance of the estimator <NUM> a computed deviation of a pose evident from the acquired image, from an optimal pose of the ultrasound probe <NUM>.

Optionally, the ultrasound probe <NUM> includes an inertial measurement unit <NUM>. The inertial measurement unit <NUM> includes each of a magnetometer 250A, a gyroscope 250B, and an accelerometer 250C. As such, data acquired by the inertial measurement unit <NUM> is translated in the host computing system <NUM> to estimate a change in pose for a given time interval, for instance by measuring linear acceleration and angular velocity of the probe <NUM>. This change in pose can be combined with an estimator-derived pose deviation to obtain a more precise pose estimate. One possible example includes the use of a Kalman filter.

For instance, algorithmically, the process utilizing the inertial measurement unit <NUM> to tune a determined deviation from the estimator <NUM> can be expressed as follows:.

In any event, based upon the computed deviation, the program code of the navigation assistance module <NUM> then determines corresponding feedback to be presented through the ultrasound probe <NUM>. For example, the program code of the navigation assistance module <NUM> may direct the tone generator <NUM> to emit a particular tone pattern of specific periodicity proportional or inversely proportional to a determined proximity of the ultrasound probe <NUM> to the optimal pose. As another example, the program code of the navigation assistance module <NUM> may direct the electromechanical vibration generator <NUM> of the ultrasound probe <NUM> to emit a particular vibration of specific intensity proportional or inversely proportional to a determined proximity of the ultrasound probe <NUM> to the optimal pose.

In yet further illustration of the operation of the navigation assistance module <NUM>, <FIG> is a flow chart depicting a process for guided navigation of an ultrasound probe. Beginning in block <NUM>, a target organ within the body is selected in a user interface to an ultrasound application visualizing ultrasound imagery acquired by the ultrasound probe. Subsequently, in block <NUM> an estimator such as a neural network pertaining to the target organ is loaded into memory of a computing system coupled to the ultrasound probe. In block <NUM>, a contemporaneous ultrasound imagery is acquired by the ultrasound probe and in block <NUM>, optionally, probe orientation and movement data is received from an inertial measurement unit of the ultrasound probe is acquired. In block <NUM>, the contemporaneous ultrasound imagery is processed in connection with to the estimator in the computing system.

In block <NUM>, a deviation of a pose of the ultrasound probe from an optimal pose that is evident from the acquired image is determined based upon the application of the estimator to the acquired image. Optionally, the probe orientation and movement data are used to further improve the accuracy of the determined pose deviation. In block <NUM>, corresponding feedback based upon the deviation is determined such as a graphical representation of the deviation, a particular strength of vibration as part of haptic feedback, or a particular tone of particular frequency, periodicity, amplitude or any combination thereof as part of audible feedback. In block <NUM>, then, the determined feedback is output by the computing system or the coupled ultrasound probe. Finally, in decision block <NUM>, the inertial measurement unit of the ultrasound probe indicates whether or not a threshold change in position or orientation has occurred with respect to the ultrasound probe. If so, or in case where an inertial measurement unit is not present or active, the process may then repeat through block <NUM>.

The present invention may be embodied within a system, a method, a computer program product or any combination thereof. The computer program product may include a computer readable storage medium or media having computer readable program instructions thereon for causing a processor to carry out aspects of the present invention.

Computer readable program instructions described herein can be downloaded to respective computing/processing devices from a computer readable storage medium or to an external computer or external storage device via a network.

Finally, the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

Claim 1:
An ultrasound navigation assistance method comprising:
acquiring an image (<NUM>) by an ultrasound probe (<NUM>; <NUM>) of a target organ of a body (<NUM>) (<NUM>);
processing the image in connection with an estimator (<NUM>; <NUM>) comprising a neural network, the estimator producing a deviation (<NUM>) of a contemporaneous pose indicative of an orientation of the ultrasound probe evident from the image from an optimal pose of the ultrasound probe for imaging the target organ (<NUM>);
wherein a change of pose obtained with an inertial measurement unit (<NUM>) is combined with a deviation produced by the estimator (<NUM>, <NUM>) using a Kalman filter, to tune the deviation produced by the estimator (<NUM>; <NUM>) and,
presenting the produced deviation to an end user operator of the ultrasound probe.