Organ Deformation Estimation from Intraoperative Point Clouds

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Laparoscopic surgeries face challenges in accurately estimating organ deformations due to insufflation gas pressure and mobilization techniques, which current methods like biomechanical modeling and intraoperative imaging require additional steps or knowledge of organ parameters, leading to inaccurate registration results.

Innovation Solution

A method using intraoperative image data to calculate point clouds and classify unmoving points, estimating partial deformations by analyzing geometric feature vectors and difference vectors without additional imaging techniques or organ-specific parameters, facilitated by a medical imaging system with a processor and optional neural networks.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If biomechanical modeling based on finite element method is used to simulate deformations, then deformation prediction capability is improved, but additional knowledge of organ parameters (stiffness) is required which may not be available

Engineering Contradiction:

Improvedeformation prediction accuracyVSAvoidrequirement for organ parameter knowledge

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The system uses the organ's own visual features (geometric feature vectors) captured in intraoperative images to estimate deformation, without requiring external parameter inputs. The unmoving points on the organ surface serve as self-referential markers that automatically provide the necessary reference information for deformation calculation.

Inventive Principle:

Principle #25Self-service

Solution Approach 2:

The patent introduces unmoving points as intermediary reference elements on the organ surface. These points act as mediators between the deformed and undeformed states, allowing deformation estimation without direct measurement of organ mechanical properties.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Measurement precision

If intraoperative imaging techniques such as CT fluoroscopy are used to model deformation, then deformation accuracy is improved, but additional surgical steps (fiducial markers) and specialized equipment are required

Engineering Contradiction:

Improvedeformation modeling accuracyVSAvoidsurgical procedure simplicity

Core Design Contradiction:

Measurement precisionVSEase of operation

Solution Approach 1:

The system utilizes the organ's inherent visual features in standard laparoscopic images to estimate deformation, eliminating the need for additional fiducial markers or specialized imaging equipment. The geometric feature vectors extracted from routine intraoperative images serve as self-sufficient reference data.

Inventive Principle:

Principle #25Self-service

Solution Approach 2:

The patent extracts only the necessary visual information (geometric feature vectors of unmoving points) from standard intraoperative images, separating the deformation estimation function from the need for specialized imaging modalities or additional surgical preparation steps.

Inventive Principle:

Principle #2Taking out (Extraction)

3Loss of information

If preoperative image data is registered with intraoperative image data, then navigation information is improved, but registration accuracy deteriorates due to organ deformation from insufflation gas and mobilization

Engineering Contradiction:

Improvenavigation information qualityVSAvoidregistration accuracy

Core Design Contradiction:

Loss of informationVSMeasurement precision

Solution Approach 1:

The system performs preliminary identification and tracking of unmoving points on the organ surface during the deformation process. By establishing these reference points before registration and maintaining their identification through the deformation, the system enables accurate post-deformation registration without requiring re-acquisition of reference data.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent implements a dynamic approach where the geometric feature vectors of unmoving points are tracked through the deformation process. The system adapts to the changing organ shape by continuously monitoring which points remain unmoved, allowing the registration process to account for non-rigid deformation while maintaining reference point validity.

Inventive Principle:

Principle #15Dynamics

Data Source

PatentUS12488457B2Method of operating a medical imaging system, method of simulating a partial deformation of a three-dimensional model of an organ, medical imaging system and software program product

Publication Date: 2025.12.02 OLYMPUS CORPORATION(JP)

AI summary

A method of estimating a partial deformation of an organ in which point clouds are calculated from intraoperative image data captured before and after a partial deformation motion of an organ. Geometric feature vectors are assigned to unmoving points, whose position does not change due to the partial deformation motion. Difference vectors indicating the change of the geometric feature vectors due to a change of position of moving in proximity to the unmoving points are utilized to estimate the partial deformation motion of the organ.