Expandable Vaso-occlusive Device with Pushable Coil Core
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current vaso-occlusive devices for treating aneurysms are difficult to position and remove, and they pose a risk of migration and harm due to their small size and limited expandability, making them ineffective for larger aneurysms and requiring longer, more complex procedures.
Innovation Solution
Development of pushable and retrievable vaso-occlusive devices with a soft, expandable braid and a coil, where the braid is attached at one end to the coil, allowing for a longer, more expandable structure that can be inserted and retrieved through a catheter, and the use of deployment tools to prevent structural failure and facilitate deployment and retrieval.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Length of moving object
If small coils are used to fill aneurysms, then the device can be pushed through the catheter, but the device has limited expandability and is difficult to position and remove
Solution Approach 1:
The device is divided into two functional segments: a pushable metal coil core and an expandable braided tubular member. The coil provides the necessary pushability through the catheter, while the braid provides expandability and anchoring. This segmentation allows each component to optimize its function without compromising the other.
Solution Approach 2:
The braided tubular member transitions from a compressed state during delivery to an expanded state at the deployment site. This dynamic transformation allows the device to be pushed through the catheter in a compact form and then expand to a larger diameter for effective aneurysm filling and anchoring, eliminating positioning and migration issues.
2Quantity of substance
If small and thin coils are used, then the device can be delivered through the catheter, but the procedure requires more coils and longer time
Solution Approach 1:
Multiple functions are merged into a single device: the metal coil provides both the delivery mechanism and structural core, while the braided tubular member provides expandability, anchoring, and filling capability. This combination eliminates the need to deploy multiple separate coils, reducing both the quantity of devices required and the procedure time.
Solution Approach 2:
The device parameters are optimized to allow a single device to replace multiple traditional coils. The braided member's expandability parameter allows it to achieve sufficient volume filling in one deployment, whereas traditional non-expandable coils would require multiple deployments to achieve the same effect.
3Volume of moving object
If long braided members are used, then the device has greater expandability for larger aneurysms, but the device becomes difficult to push and retrieve
Solution Approach 1:
The device separates the pushability function (metal coil core) from the expandability function (braided tubular member). The coil's rigid structure provides the necessary pushability through the catheter, while the braid's flexible structure provides expandability. This segmentation allows long braided members to be delivered without compromising pushability.
Solution Approach 2:
The braided tubular member acts as a flexible shell that can be compressed during delivery and then expanded at the target site. This flexible structure allows the device to navigate through the catheter in a compact form and then expand to a large volume for treating larger aneurysms, maintaining both pushability and expandability.
4Stability of the object's composition
If the braided member is attached at both ends to the coil, then the structure is stable, but the device becomes difficult to push and retrieve
Solution Approach 1:
The distal attachment is removed, leaving only the proximal attachment between the coil and braided member. This extraction of the distal attachment point maintains sufficient structural stability for aneurysm filling while dramatically improving pushability and retrievability by eliminating the constraint that would prevent device movement through the catheter.
Solution Approach 2:
The device transitions from a constrained state during delivery to a stable deployed state. During delivery, the single proximal attachment allows the braid to move freely over the coil, enabling easy pushability. After deployment, the braid expands and becomes stabilized by friction and anchoring mechanisms, providing sufficient stability for aneurysm filling without requiring distal attachment.
Data Source
AI summary
Vaso-occlusive apparatuses, including implants, and methods of using them to treat aneurysms. For example, described herein are expandable vaso-occlusive implants that include one or more soft and expandable braided member coupled to a pushable member such as a coil that maybe inserted and retrieved from within an aneurism using a delivery catheter. In particular, the expandable implants described herein are configured to allow relatively soft and elongate implants to be pushed out of a cannula without binding up within the cannula.