Shear Wave Vibro-Elastography Abdominal Ribcage Obstruction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing medical imaging techniques face challenges in performing effective shear-wave elastography on deep tissues, particularly in the abdomen, due to the obstruction caused by the ribcage, which hinders consistent shear wave transmission and accurate measurement of mechanical properties of organs like the liver.
Innovation Solution
The development of an apparatus and method that includes an external vibrator with a patient-contacting member and multiple exciters to generate and control shear waves, coupled with an ultrasound imaging system and data processor to optimize shear wave direction and minimize vibrational nodes, allowing for deep and consistent shear wave transmission through the ribcage, enabling accurate measurement of mechanical properties like Young's modulus and viscosity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Length of stationary object
If traditional ultrasound imaging techniques are used for deep abdominal tissues, then the imaging depth is limited, but the ribcage obstructs the imaging field and prevents consistent shear wave transmission
Solution Approach 1:
The patent introduces an intermediary medium (coupling gel or fluid) between the ultrasound transducer and the patient's skin to facilitate shear wave transmission through the ribcage. This intermediary compensates for the obstructive effect of ribs by providing a continuous medium for wave propagation, enabling deeper tissue imaging while maintaining consistent shear wave transmission.
Solution Approach 2:
The patent employs multiple exciters arranged in specific spatial configurations (e.g., arrays of vibrators) to generate shear waves from multiple directions and dimensions. This multi-dimensional approach allows the shear waves to propagate through the ribcage by exploiting alternative pathways, overcoming the obstruction and enabling imaging at greater depths.
2Reliability
If multiple exciters are used to generate shear waves, then shear wave transmission consistency is improved, but the device complexity increases
Solution Approach 1:
The patent divides the excitation system into multiple independent exciters (vibrators) that can be individually controlled and positioned. Each exciter operates as a separate unit, allowing the system to achieve consistent shear wave transmission through distributed excitation while maintaining modular simplicity. The segmentation enables reliable wave generation without requiring a monolithic complex device.
Solution Approach 2:
The patent designs the exciters to be multifunctional, serving both as shear wave generators and as positioning references. The same mechanical components that generate vibration also provide structural support and spatial orientation, reducing the need for separate control mechanisms and simplifying the overall device architecture while maintaining transmission consistency.
3Measurement precision
If shear waves are transmitted through the ribcage, then deep tissue mechanical properties can be measured, but vibrational nodes are created that interfere with measurement accuracy
Solution Approach 1:
The patent employs dynamic control of the exciter frequencies and phases to actively manage vibrational node formation. By continuously adjusting the excitation parameters in response to real-time feedback from tissue response measurements, the system can shift or eliminate nodes that would otherwise interfere with accurate mechanical property measurement, maintaining high measurement precision despite wave transmission through the ribcage.
Solution Approach 2:
The patent implements a feedback mechanism where the measured tissue response is used to adjust the exciter parameters. The system monitors the generated shear waves and their interaction with tissue, identifying vibrational nodes through the returned signal characteristics. This feedback information is then used to modify excitation frequencies or phases to minimize node formation in the region of interest, ensuring accurate mechanical property measurements.
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 solution enables the effective measurement of mechanical properties of abdominal organs by ensuring consistent shear wave transmission and optimizing wave direction, overcoming the limitations of traditional methods and providing reliable elastography images.
Implementation Method 1
an external vibrator comprising a generally flat, stiff, patient-contacting member dimensioned to support at least a portion of the back of a patient, at least one exciter coupled to drive vibration of the patient-contacting member
Implementation Method 2
an ultrasound imaging system comprising an ultrasound transducer, driving circuits operative to drive the ultrasound transducer to transmit ultrasound pulses and to receive ultrasound echo signals
Implementation Method 3
a data processor configured to process the ultrasound echo signals to detect and measure motions corresponding to shear waves generated by the external vibrator
Data Source
Figure 1
Figure 2
Figure 3A~3B
AI summary
A system useful for performing ultrasound elastography of organs such as the liver allows efficient and robust data acquisition. The system may be applied to perform real-time, non- invasive ultrasound imaging of the liver in humans. Steady-state, shear wave absolute elastography is used to measure the Young's modulus of the liver tissue. This method involves the use of an external exciter or vibrator to shake the tissue and generate a shear wave. Accurate placement of an ultrasound transducer facilitates measurement of the tissue motion due to the shear wave. The stiffness of tissues in the region being imaged may be computed from the measured tissue motions. The following innovations address both vibrator and transducer placement, as well as some specific methods to ensure adequate wave propagation, in order to obtain accurate and consistent measurements.