Stimulus-Responsive Hydrogel Tear Duct Occlusion With Easy Removal
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Punctal plugs used for occluding tear ducts suffer from issues such as extrusion, migration, and difficulty in removal, leading to high replacement rates and patient discomfort, with little innovation in the product category over the past 20 years.
Innovation Solution
Hydrogels composed of binary copolymers, specifically comprising C1-C4 N-alkyl acrylamides and C5-C18 alkyl acrylates or methacrylates, which can be formulated to undergo controlled changes in material properties in response to environmental stimuli, allowing for precise occlusion and removal from tear ducts.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Duration of action of stationary object
If pre-molded silicone plugs are used for permanent treatment, then durability is improved, but fit and comfort deteriorate leading to extrusion
Solution Approach 1:
The plug material transitions from rigid silicone to a hydrogel composition that changes its physical parameters (viscoelasticity, swelling ratio) in response to physiological stimuli. The hydrogel swells to achieve optimal fit within the tear duct and can be removed by changing its physical state, resolving the contradiction between durability and fit.
Solution Approach 2:
The invention uses a composite hydrogel material combining multiple polymers (polyacrylamide, polyalkyl acrylate, and crosslinking agents) to achieve both durability and adaptability. This composite structure provides mechanical strength while allowing swelling and shape change to improve fit and comfort.
2Ease of operation
If collagen plugs are used for temporary treatment, then comfort is improved, but duration of action deteriorates requiring frequent replacement
Solution Approach 1:
The hydrogel plug maintains comfort through its soft, gel-like consistency while extending duration of action by utilizing controlled swelling and gradual degradation. The material can be adjusted to last from weeks to months depending on formulation, providing both comfort and extended wear time.
3Duration of action of stationary object
If plugs are designed for permanent insertion, then durability is improved, but removal difficulty worsens requiring surgical intervention
Solution Approach 1:
The hydrogel plug is designed with reversible physical changes - it can be removed by changing its physical state through exposure to specific solutions or temperature changes. This allows the plug to be easily removed without surgical intervention while maintaining permanent treatment capabilities when needed.
4Ease of manufacture
If standard silicone plugs are used, then manufacturing simplicity is improved, but reliability deteriorates due to migration and extrusion
Solution Approach 1:
The hydrogel material changes its physical parameters (viscoelasticity, surface properties) in response to physiological stimuli, creating a dynamic interface with the tear duct. This reduces migration and extrusion by allowing the material to adapt to dimensional changes in the duct while maintaining secure positioning.
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 hydrogels provide a solution for effective and controlled occlusion of tear ducts, reducing extrusion and migration rates, and enabling easy removal, thus improving patient comfort and reducing clinical visits for replacement.
Implementation Method 1
The copolymer is used to engineer precise behaviors in stimulus responsive polymers such that they undergo a controlled change in material properties, behavior, or structure upon a selected environmental stimulus
Data Source
AI summary
Described herein are hydrogels composed of binary copolymers. In one aspect, the copolymer comprises at least one residue from (a) an acrylamide selected from the group consisting of a C1-C4 N-alkyl acrylamide, a C1-C4 N,N-dialkyl acrylamide, and a combination thereof and (b) an alkyl acrylate selected from the group consisting of a C5-C18 alkyl acrylate, a C5-C18 alkyl methacrylate, and a combination thereof, wherein the alkyl acrylate is at most 3 weight percent of the copolymer. The hydrogels can be used to occlude a duct or channel in a subject. For example, the hydrogels can occlude a tear duct, which has numerous medical benefits as described herein.