Twisted Microprobe with Central Support for Deep Brain Stimulation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current deep brain stimulation microprobes face challenges in achieving a balance between small diameter for minimally invasive implantation, navigability through the cerebral venous network, and the ability to support a high number of independently programmable electrodes for precise stimulation, while avoiding neurological damage and side effects.

Innovation Solution

A microprobe with a twisted structure of up to 100 insulated wires, each with a diameter of less than 0.5 mm, and a central support structure that allows for elastic deformation and MRI protection, enabling precise stimulation and long-term implantation with multiple electrodes oriented in various directions.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If the probe diameter is reduced to less than 1.5 French (0.5 mm) for minimally invasive implantation, then neurological damage is reduced and navigability is improved, but the structural rigidity is compromised making it difficult to place and transmit rotational movements

Engineering Contradiction:
Improveneurological damageVSAvoidtorsional rigidity
Core Design Contradiction:
Object-affected harmful factorsVSStrength

Solution Approach 1:

The probe employs a composite structure combining a flexible polymer jacket (elastomer or thermoplastic) with embedded conductive wires and a central support element. This composite design allows the probe to maintain sufficient torsional rigidity for placement and stimulation while keeping the overall diameter under 1.5 French to minimize neurological damage during implantation.

Inventive Principle:
Principle #40Composite materials

Solution Approach 2:

The probe structure implements local quality variations through a tapered configuration where the distal tip has a smaller diameter than the proximal portion. This allows the tip to be sufficiently flexible for navigating the venous network while the proximal portion maintains structural integrity for transmitting rotational movements and providing torsional rigidity when needed.

Inventive Principle:
Principle #3Local quality

2Ease of operation

If the probe is made more flexible to improve navigability through the venous network, then insertion is easier, but the ability to transmit rotational movements and maintain structural integrity is lost

Engineering Contradiction:
ImprovenavigabilityVSAvoidstructural integrity
Core Design Contradiction:
Ease of operationVSStrength

Solution Approach 1:

The probe features a tapered structure with a distal tip diameter smaller than the proximal portion, creating local quality variations. The distal tip is more flexible for navigating the venous network, while the proximal portion maintains structural integrity for transmitting rotational movements and providing torsional rigidity when needed.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The composite construction with polymer jacket, conductive wires, and central support element allows different regions of the probe to have different mechanical properties. The flexible polymer enables navigability while the embedded structure maintains structural integrity for functional operations.

Inventive Principle:
Principle #40Composite materials

3Measurement precision

If the number of independently programmable electrodes is increased to at least 8 (preferably 20 to 100) for precise stimulation, then stimulation precision is improved, but the probe diameter increases and traumatic effect is amplified

Engineering Contradiction:
Improvestimulation precisionVSAvoidtraumatic effect
Core Design Contradiction:
Measurement precisionVSObject-affected harmful factors

Solution Approach 1:

The probe divides the stimulation function into multiple segmented conductive wires (at least 8, preferably 20 to 100) that are independently programmable. Each wire can be selectively activated to stimulate specific target areas, enabling precise multipoint stimulation while keeping each individual conductor thin to minimize overall probe diameter and traumatic effect.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The probe arranges conductors in a three-dimensional configuration within the polymer jacket, allowing multiple independently programmable electrodes to be positioned at different spatial locations and orientations. This dimensional arrangement enables precise stimulation of deep brain structures without requiring a proportionally large probe diameter.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

4Object-affected harmful factors

If the electrode surface area is reduced to minimize psychiatric side effects, then stimulation safety is improved, but the stimulation effectiveness may be compromised

Engineering Contradiction:
Improvepsychiatric side effectsVSAvoidstimulation effectiveness
Core Design Contradiction:
Object-affected harmful factorsVSPower

Solution Approach 1:

The probe segments the total stimulation function across multiple thin conductive wires, each with small surface area. By distributing the stimulation load across at least 8 (preferably 20 to 100) independent electrodes, the system achieves effective stimulation through distributed low-power contacts, minimizing psychiatric side effects while maintaining therapeutic effectiveness.

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 microprobe achieves precise stimulation of deep brain areas with reduced neurological risk, improved navigability, and long-term biostability, while maintaining a small diameter compatible with interventional neuroradiology catheters, allowing for effective treatment of conditions like Parkinson's disease and epilepsy.

Implementation Method 1

a plurality of at least eight individually insulated conducting wires twisted together, each conducting wire comprising: an electrically conductive core microcable, suitable for being connected in its proximal part to a pole of a generator of an active implantable medical device

Methodology Applied
Scientific EffectElectrical conduction: Conduction (electrical)

Implementation Method 2

a central support structure in the form of a surface of revolution, this central support structure being devoid of i) a conducting wire and ii) a central light

Methodology Applied
Scientific EffectElastic deformation: Elasticity

Data Source

PatentEP3058983B1Detection/stimulation microprobe, in particular for multipoint neuromodulation of the central nervous system
Publication Date: 2021.10.13 SORIN CRM
  • EP3058983B1 patent drawingFigure 1~3d
  • EP3058983B1 patent drawingFigure 4~7
  • EP3058983B1 patent drawingFigure 8

AI summary

This microprobe (10), with an overall diameter of less than 1.5 French (0.5 mm), comprises a plurality of at least eight individually insulated conducting wires (14, 14') twisted together. Each conducting wire includes an electrically conductive microcore cable and an insulating layer (18) surrounding the core cable and having at least one bare area (38, 38') to form a sensing/stimulation electrode for the microprobe. The microprobe further comprises a central support structure (12) in the form of a surface of revolution, devoid of conducting wire and a central lumen. The conducting wires (14, 14') are configured in one or more layers of twisted peripheral conducting wires, carried by the central support structure (12) and circumferentially distributed thereon.