Lamb Wave Pressure Estimation for Non-Invasive Biological Compartments

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current methods for measuring pressure in biological compartments, such as the bladder, are invasive and lack a mechanistic understanding of how elastic wave speed relates to pressure, leading to the need for a non-invasive and accurate estimation method.

Innovation Solution

A system and method using Lamb wave acoustoelastic analysis with spherical pressure-vessel analysis to determine pressure from ultrasonically measured Lamb wave speed, incorporating finite deformation and wave dispersion, allowing for non-invasive pressure estimation in biological compartments.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If invasive pressure measurement procedures are used, then measurement precision is improved, but patient comfort and morbidity worsen

Engineering Contradiction:
Improvepressure measurement accuracyVSAvoidpatient discomfort and morbidity
Core Design Contradiction:
Measurement precisionVSObject-affected harmful factors

Solution Approach 1:

The patent replaces the mechanical invasive catheter-based pressure measurement system with an acoustic wave-based non-invasive measurement system. Lamb waves are generated in the tissue wall and their propagation characteristics are used to infer internal fluid pressure without mechanical intrusion into the biological compartment.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent introduces tissue wall as an intermediary medium that transmits acoustic information from the internal fluid pressure to external sensors. The Lamb waves propagate through the tissue wall, carrying encoded pressure information that can be decoded externally without direct contact with the internal fluid.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Ease of operation

If empirical correlations are used for pressure estimation, then ease of operation is improved, but measurement precision deteriorates due to lack of mechanistic understanding

Engineering Contradiction:
Improvesimplicity of pressure estimationVSAvoidaccuracy of pressure estimation
Core Design Contradiction:
Ease of operationVSMeasurement precision

Solution Approach 1:

The patent changes the approach from using simple empirical correlations to incorporating multiple physical parameters including wave dispersion effects, tissue wall thickness, and acoustoelastic properties. This multi-parameter approach maintains operational simplicity while significantly improving measurement precision through a mechanistic understanding of wave-pressure relationships.

Inventive Principle:
Principle #35Parameter changes

3Object-affected harmful factors

If conventional wave-based elastographic techniques are used, then non-invasive assessment is achieved, but measurement precision is insufficient due to lack of comprehensive mechanical analysis

Engineering Contradiction:
ImproveinvasivenessVSAvoidaccuracy of pressure inference
Core Design Contradiction:
Object-affected harmful factorsVSMeasurement precision

Solution Approach 1:

The patent applies composite analysis by combining acoustoelastic wave propagation theory with hyperelastic solid mechanics and pressure-vessel analysis. This composite theoretical framework integrates multiple physical disciplines to achieve accurate non-invasive pressure measurement that accounts for the complex mechanical behavior of biological tissues under finite deformation.

Inventive Principle:
Principle #40Composite materials

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

Provides accurate and non-invasive pressure estimation in biological compartments, achieving greater accuracy than conventional methods by accounting for compartment characteristics and adapting analysis to individual variations.

Implementation Method 1

with a transducer, generating Lamb waves in a tissue wall of the tissue volume using radiation force

Methodology Applied
Scientific EffectAcoustic radiation force: Acoustic Radiation Pressure

Implementation Method 2

forming ultrasonic echo data by detecting ultrasonic energy reflected by multiple locations along the tissue volume

Methodology Applied
Scientific EffectUltrasonic reflection: Reflection

Data Source

PatentEP4362811B1System and method for non-invasive determination of pressure in a biological compartment
Publication Date: 2026.02.25 MAYO FOUNDATION FOR MEDICAL EDUCATION & RESEARCH
  • EP4362811B1 patent drawingFigure 1
  • EP4362811B1 patent drawingFigure 2
  • EP4362811B1 patent drawingFigure 3

AI summary

Systems and methods are provided for a mechanical analysis for determining a kinetic value, such as pressure, from ultrasonically measured Lamb wave speed in a pressurized biological compartment. Acoustoelastic analysis of Lamb waves may be used to determine pressure in a biological compartment, such as with a spherical pressure-vessel analysis. Non-invasive pressure estimation is provided in biological compartments which is relevant to a range of biological structures.