3D Image Calibrator for Automated Surgical Registration

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current surgical navigation systems require complex calibration processes that depend on 3D imaging device parameters, making intraoperative 3D image registration challenging and difficult to implement.

Innovation Solution

A calibrator for 3D image registration system comprising a flat or arc-shaped calibrator plane with marked points, connected to a surgical robotic arm, which allows for automatic intraoperative 3D image registration without relying on 3D imaging device parameters, using a spatial measurement device and trackers to identify and match geometric features.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If traditional image registration methods using fluoroscopy images or contour matching are used, then 3D image registration can be achieved, but the process requires complex calibration depending on 3D imaging device parameters and manual intervention

Engineering Contradiction:
Improveimage registration precisionVSAvoidcalibration process complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent introduces a calibrator as an intermediary object with known geometric features (marked points on a plane) that mediates between the 3D imaging device and the surgical robot. The calibrator provides a common reference framework that both systems can identify, eliminating the need for complex direct calibration between them. The calibrator's marked points serve as intermediate reference markers that simplify the coordinate system transformation process.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent uses a simplified 2D representation (marked points on the calibrator plane) to copy and represent the essential geometric information needed for registration, rather than directly processing complex 3D imaging device parameters or fluoroscopy images. This copying approach reduces the complexity of the calibration process while maintaining registration precision.

Inventive Principle:
Principle #26Copying

2Measurement precision

If fluoroscopy images from multiple angles are used for registration, then registration accuracy can be improved, but the process requires matching contours or edges using special algorithms and increases time consumption

Engineering Contradiction:
Improveregistration accuracyVSAvoidregistration time
Core Design Contradiction:
Measurement precisionVSLoss of time

Solution Approach 1:

The patent uses marked points with distinct visual characteristics (analogous to color changes) on the calibrator that are easily identifiable by both the 3D imaging device and the spatial measurement device. These marked points provide clear, unambiguous reference features that can be automatically detected and matched, eliminating the need for complex contour or edge matching algorithms and reducing registration time.

Inventive Principle:
Principle #32Color changes

Solution Approach 2:

Instead of processing complex fluoroscopy images and matching contours, the patent copies the essential registration information into simple marked point positions on the calibrator. This copied representation is much easier and faster to process automatically, significantly reducing registration time while maintaining accuracy.

Inventive Principle:
Principle #26Copying

3Measurement precision

If preoperative 3D images with markers are used for registration, then accurate coordinate transformation can be achieved, but the method requires special markers attached to the patient and complex pairing processes during surgery

Engineering Contradiction:
Improvecoordinate transformation precisionVSAvoidsurgery process simplicity
Core Design Contradiction:
Measurement precisionVSEase of operation

Solution Approach 1:

The calibrator serves as an intermediary that eliminates the need for attaching markers to the patient. The calibrator is attached to the surgical robot instead, and its marked points provide the reference framework for coordinate transformation. This intermediary approach simplifies the surgical process by removing the complex step of patient marker attachment and pairing.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

Instead of attaching markers to the patient and using them as the reference framework, the patent inverts the approach by attaching the calibrator with marked points to the surgical robot. This inversion simplifies the process by making the robot the reference carrier rather than the patient, eliminating the need for patient marker attachment and making the system easier to operate.

Inventive Principle:
Principle #13The other way round (Inversion)

4Ease of operation

If automatic intraoperative 3D image registration is implemented without 3D imaging device parameters, then ease of operation is improved, but measurement precision may be compromised

Engineering Contradiction:
Improveregistration process automationVSAvoidimage registration precision
Core Design Contradiction:
Ease of operationVSMeasurement precision

Solution Approach 1:

The calibrator with its precisely manufactured marked points serves as an intermediary reference standard that enables automatic registration without compromising precision. The known geometric relationships between the marked points on the calibrator provide a reliable reference framework that both the 3D imaging device and spatial measurement device can use for accurate coordinate transformation, even without direct access to 3D imaging device parameters.

Inventive Principle:
Principle #24Intermediary (Mediator)

Data Source

PatentEP3254621B13D image special calibrator, surgical localizing system and method
Publication Date: 2020.07.22 BEIJING TINAVI MEDICAL TECH
  • EP3254621B1 patent drawingFigure 1~2
  • EP3254621B1 patent drawingFigure 3

AI summary

The present invention relates to a calibrator for 3D image, a surgical positioning system, and a positioning method. The calibrator for 3D image includes a calibrator plane and a calibrator handle. The calibrator plane is flat or arc-shaped, and at least four marked points to be identified by a 3D imaging device are arranged on the calibrator plane. One end of the calibrator handle is fixedly connected to the calibrator plane, and the other end of the calibrator is provided with a connector for connecting to a surgical robotic arm.