Magnetic Marker for Surgical Tissue Localization

Solution Overview

Problem

Current radioactive localization techniques for breast cancer surgery are underutilized due to laborious implementation and limited accessibility of medical radioisotopes, leading to unnecessary pain, logistical challenges, and inaccuracy, with a high reoperation rate, while existing magnetic markers introduce a foreign body that may interfere with future procedures or take long to absorb.

Innovation Solution

A magnetic marker system comprising a casing with multiple, high-susceptibility ferromagnetic elements of predetermined size and shape, introduced only after tissue removal confirmation, optimized for detectability with a magnetometer, and designed for non-bioabsorbability to maintain signal consistency and precision, using a hollow needle for placement.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If a magnetic marker is placed directly after biopsy sample removal, then the tissue for surgery can be located by magnetic detection, but the magnetic marker remains in the body as a foreign body that may interfere with future procedures or induce unwanted side effects

Engineering Contradiction:

Improvelocalization accuracyVSAvoidforeign body interference

Core Design Contradiction:

Measurement precisionVSObject-affected harmful factors

Solution Approach 1:

The magnetic marker is placed at the biopsy site immediately after biopsy sample removal, before final pathology confirmation. This preliminary action ensures the marker is already in position when surgery is needed, eliminating the need for re-introduction while the pathology analysis determines whether surgery is required

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The magnetic marker is removed from the body after surgery is completed, since it has served its localization purpose. This extraction eliminates the foreign body from the patient, preventing long-term interference with future diagnostic procedures while maintaining the benefits of accurate localization during the surgical process

Inventive Principle:

Principle #2Taking out (Extraction)

2Measurement precision

If a magnetic marker is placed directly after biopsy, then localization is ready for surgery, but the marker may be present in the body for a long time before absorption

Engineering Contradiction:

Improvelocalization accuracyVSAvoidmarker retention time

Core Design Contradiction:

Measurement precisionVSDuration of action of stationary object

Solution Approach 1:

The magnetic marker is placed at the biopsy site immediately after biopsy sample removal, before final pathology confirmation. This preliminary action ensures the marker is already in position when surgery is needed, eliminating the need for re-introduction while the pathology analysis determines whether surgery is required

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The magnetic marker is removed from the body after surgery is completed, since it has served its localization purpose. This extraction eliminates the foreign body from the patient, preventing long-term interference with future diagnostic procedures while maintaining the benefits of accurate localization during the surgical process

Inventive Principle:

Principle #2Taking out (Extraction)

3Measurement precision

If multiple magnetic elements are used in the marker, then detectability with magnetometer is improved, but the device complexity increases

Engineering Contradiction:

ImprovedetectabilityVSAvoidmarker structure

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The magnetic marker is divided into multiple discrete magnetic elements (typically 2-5 elements) arranged in a linear configuration within the marker housing. This segmentation increases the overall magnetic signal detectability by the magnetometer while maintaining a simple, manufacturable structure that can be produced using conventional techniques

Inventive Principle:

Principle #1Segmentation

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

The magnetic marker system enhances surgical precision by providing accurate localization with reduced reoperation rates and minimizing foreign body interference, maintaining signal consistency over time, and allowing for precise tumor removal while sparing normal tissue.

Implementation Method 1

the magnetic marker comprises a casing and a multiple, preferably two to five, magnetic elements arranged in a row in the casing. The magnetic elements of the invention are bodies of ferromagnetic material having a predetermined size and shape.

Methodology Applied

Scientific EffectFerromagnetism: Ferromagnetism

Implementation Method 2

The magnetic elements are unmagnetized, but have a high magnetic susceptibility. This means that the magnetic elements show a relatively large magnetization in the presence of an externally applied magnetic field.

Methodology Applied

Scientific EffectMagnetization: Magnetic Field

Data Source

PatentUS11937909B2Magnetic marker, location detection system, introducer and method

Publication Date: 2024.03.26 SIRIUS MEDICAL SYST BV

AI summary

A magnetic marker for use in locating tissue for surgery includes a casing and two to five magnetic elements arranged in a row. The two or more magnetic elements are separated from each other by an isolating material. The magnetic marker may be non-bio-absorbable. This means that the magnetic marker is invariable as it does not decay over time. This invariability ensures that on the basis of the signal measured by a magnetometer device a distance between a probe of the magnetometer device and the magnetic marker can be determined.