Ultrasound Sensor Tracking for 3D Instrument Localization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
During ultrasound-guided interventional procedures, such as prostate biopsies, the use of 2D ultrasound imaging leads to poor instrument contrast and positional errors due to the 'invisible tool' phenomenon, where needles are not accurately visualized in 3D space, complicating precise needle insertion.
Innovation Solution
A tracking device and method that utilize an ultrasound imaging device with an electronic processor to perform 2D ultrasound sweeps, detect signals from sensors on the interventional instrument, and transform these signals into 3D space information, allowing for accurate localization and display of the instrument's tip location and orientation on a 2D ultrasound image.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If 2D ultrasound imaging is used for live guidance, then the procedure speed and cost are improved, but instrument visibility and localization accuracy deteriorate due to the 'invisible tool' phenomenon
Solution Approach 1:
The patent introduces ultrasound sensors as intermediary elements attached to the interventional instrument. These sensors act as mediators that actively respond to ultrasound beams, generating detectable signals that enable precise localization of the instrument in 3D space. This resolves the contradiction by maintaining the simplicity and speed of 2D ultrasound imaging while adding sensors that provide the missing visibility and localization accuracy.
Solution Approach 2:
The patent replaces reliance on passive mechanical visualization of the instrument in 2D ultrasound images with an active acoustic signaling system. Instead of depending on the instrument's physical presence being visible in the ultrasound image, the system uses ultrasound sensors that emit acoustic signals in response to ultrasound beams, enabling electronic detection and tracking of the instrument's position and orientation.
2Measurement precision
If 3D ultrasound imaging equipment is used, then instrument visibility and 3D localization accuracy are improved, but the cost and device complexity increase
Solution Approach 1:
The patent extracts the essential function of 3D localization from complex 3D ultrasound imaging equipment and implements it through a simpler system. By attaching ultrasound sensors to the instrument and using 2D ultrasound sweeps to detect sensor responses, the system achieves 3D localization accuracy without requiring expensive and complex 3D ultrasound imaging hardware.
Solution Approach 2:
The patent creates a simplified copy of the 3D localization capability by using ultrasound sensors that respond to 2D ultrasound sweeps. Instead of implementing full 3D ultrasound imaging, the system uses the temporal and spatial patterns of sensor responses to 2D sweeps to reconstruct 3D position information, achieving the same localization goal with simpler equipment.
3Reliability
If ultrasound sensors are mounted on the interventional instrument, then instrument visibility is improved, but the device complexity and cost increase
Solution Approach 1:
The patent makes the ultrasound imaging device multi-functional by enabling it to perform both traditional 2D imaging and sensor detection for tracking. The same ultrasound beams used for imaging are also used to sonicate the sensors, and the same transducer array detects both tissue echoes and sensor responses. This eliminates the need for separate tracking hardware and reduces overall system complexity.
Solution Approach 2:
The ultrasound imaging device serves itself by using its own ultrasound beams to both image the tissue and detect the position of the instrument. The system leverages its existing capability to generate and detect ultrasound signals, applying the same functionality to track the instrument without requiring external or additional specialized hardware.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach provides accurate and reliable three-dimensional information about the interventional instrument during procedures without the need for costly 3D ultrasound imaging equipment, enhancing precision and reducing errors in needle placement.
Implementation Method 1
perform 2D ultrasound sweeps of a plurality of planes... detecting a signal emitted by each ultrasound sensor in response to the 2D ultrasound sweep
Implementation Method 2
the time interval between ultrasound pulse emission and the sensor response ('time of flight') enables localization of the sensor
Data Source
AI summary
An interventional instrument (30) having ultrasound sensors (S1, S2, S3, S4, . . . ) is tracked using an ultrasound imaging device (10) that acquires and displays a 2D ultrasound image of a visualization plane (18), and performs 2D ultrasound sweeps for a range of plane angles (θ) obtained by rotating the ultrasound probe (12) and encompassing the visualization plane angle. For each ultrasound sensor, an optimal plane is found based on its emitted signal strength over the range of plane angles, and the ultrasound sensor is located in its optimal plane by analyzing the sensor signal as a function of the timing of the beams fired by the ultrasound probe. These locations in their respective optimal planes are transformed to a 3D reference space using a transform (42) parameterized by plane angle, and a visual indicator is displayed of spatial information (T, L) for the interventional instrument generated from the locations of the one or more ultrasound sensors in the 3D reference space.