Multi-Lumen Injector for Implantable Fluid Exchange and Leak Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for exchanging fluids in implantable devices, particularly those implanted in the eye, face challenges such as inefficient fluid mixing, device damage, leakage, and difficulty in alignment, which can lead to suboptimal therapeutic delivery and increased invasiveness.
Innovation Solution
An elongate structure with multiple openings and a distal tip is used to penetrate the implantable device, allowing for efficient fluid exchange by separating therapeutic and implantable device fluids, while a sheath and tapered portion maintain barrier integrity and prevent leakage, coupled with a receiver container to collect samples for analysis.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If a needle is used to inject therapeutic fluid into the implantable device, then the therapeutic fluid can be delivered to the device, but the needle may damage the implantable device septum with repeated injections
Solution Approach 1:
The injector apparatus is divided into a reusable outer body and a disposable needle assembly. The needle can be replaced after a certain number of uses while the main injector body remains intact, allowing frequent fluid exchanges without repeatedly damaging the implantable device septum.
Solution Approach 2:
The needle is designed as a disposable component that is replaced after limited use. This eliminates the cumulative damage to the device septum that would occur with repeated needle injections, while the reusable injector body maintains long-term functionality.
2Productivity
If high pressure is applied to the implantable device chamber to provide clinically acceptable fluid exchange time, then fluid exchange speed is improved, but fluid leakage may occur from the device or injector apparatus
Solution Approach 1:
A seal is formed between the injector apparatus and implantable device before high pressure is applied. The needle penetrates the septum and creates a sealed connection in advance, preventing fluid leakage when pressure is subsequently applied to accelerate fluid exchange.
Solution Approach 2:
The sealing mechanism is prepared and engaged before pressure application to cushion against the harmful effect of leakage. The seal compensates for potential pressure-induced gaps, ensuring contained fluid exchange even at high pressures.
3Weight of moving object
If the refill port of the implanted device is made small to decrease interference with vision, then visual interference is reduced, but alignment of the injection apparatus with the refill port becomes more difficult
Solution Approach 1:
The injector apparatus incorporates asymmetric alignment features such as a flat side or directional indicator on the needle assembly that corresponds to asymmetric features on the refill port. This asymmetric design provides tactile and visual guidance for proper orientation, making alignment easier despite the small port size.
Solution Approach 2:
An alignment guide or indicator structure serves as an intermediary between the injector apparatus and the small refill port. This intermediary provides tactile feedback or visual markers that facilitate precise alignment without requiring the port itself to be larger.
4Device complexity
If a single lumen needle is used for fluid injection, then the device structure is simple, but the therapeutic fluid may mix with existing device fluid resulting in suboptimal therapeutic delivery
Solution Approach 1:
The needle is divided into multiple lumens, with separate channels for withdrawing device fluid and injecting therapeutic fluid. This segmentation prevents mixing of the two fluids during the exchange process, ensuring precise therapeutic delivery while maintaining a relatively simple overall structure.
Solution Approach 2:
The multi-lumen needle performs multiple functions simultaneously: fluid withdrawal, fluid injection, and fluid separation. This multi-functionality achieves precise fluid exchange without requiring separate devices for each function, balancing complexity with performance.
Data Source
Figure 1~2
Figure 3A~3B
Figure 4
AI summary
An injector apparatus comprises an elongate structure having one or more openings positionable near a penetrable barrier of an implantable device so as to receive fluid of the implantable device. The apparatus comprises a needle and a sheath extending over at least a portion of the needle. The elongate structure may comprise a distal tip to penetrate tissue and the penetrable barrier, and a distal opening near the tip to release therapeutic fluid into the implantable chamber. In many embodiments the distal tip, the distal opening, and the plurality of openings are separated from a stop that engages a tissue of the patient and limit penetration depth such that the distal opening and the plurality of openings are located along an axis of the implantable device to increase an efficiency of the exchange.