Intraocular Lens Injection Plunger Asperities Prevent Lens Breakage

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing IOL injection instruments face issues with the deformation and breakage of intraocular lenses during insertion due to insufficient folding and the risk of the plunger contacting the lens, leading to complications such as postoperative astigmatism and increased surgical time.

Innovation Solution

The design incorporates a plunger with a tip portion featuring a curved surface and asperities to prevent the lens from slipping into gaps and to maintain contact with the lens edge, ensuring proper folding and insertion without deformation or breakage, while the asperities provide friction to restrain the lens from entering the gap between the plunger and the injector wall.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Length of moving object

If the front opening of the injector is made small to minimize incision size, then the incision diameter is reduced, but the rear support part may be caught between the front opening and plunger causing breakage

Engineering Contradiction:
Improveincision diameterVSAvoidrisk of support part breakage
Core Design Contradiction:
Length of moving objectVSReliability

Solution Approach 1:

The patent applies preliminary action by forming a gap between the plunger front end and injection part inner wall surface before the support part reaches this region. The gap is pre-formed at a position where the optical part is likely to contact the plunger, allowing the support part to pass through safely without being caught between components during the injection process

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The gap acts as an intermediary space that mediates between the plunger and injection part inner wall. This intermediate space prevents direct contact and potential pinching of the support part, allowing smooth passage while maintaining the small incision size requirement

Inventive Principle:
Principle #24Intermediary (Mediator)

2Force

If the optical part is pushed strongly by the plunger to ensure injection, then the injection force is sufficient, but the optical part may deform or slip into the gap between plunger and injection part wall

Engineering Contradiction:
Improvepushing forceVSAvoidoptical part deformation
Core Design Contradiction:
ForceVSManufacturing precision

Solution Approach 1:

The patent applies beforehand cushioning by creating a gap between the plunger front end and the injection part inner wall surface. This gap serves as a cushioning space that prevents the optical part from slipping into the gap between plunger and wall during strong pushing, while still allowing sufficient injection force to be applied

Inventive Principle:
Principle #11Beforehand cushioning (Prior cushioning)

Solution Approach 2:

The patent converts the potential harmful effect of strong pushing (which could cause deformation or slippage) into a beneficial outcome by pre-forming a gap. The gap absorbs the excess force and prevents damage, transforming what could be a harmful situation into a safe and effective injection process

Inventive Principle:
Principle #22Blessing in disguise (Convert harm into benefit)

3Productivity

If the plunger contacts the optical part directly to push it forward, then the pushing action is direct and effective, but the optical part may be broken or the plunger may further get onto the optical part

Engineering Contradiction:
Improveinjection efficiencyVSAvoidrisk of optical part breakage
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The gap between the plunger front end and injection part inner wall surface serves as an intermediary space that prevents direct harmful contact between the plunger and optical part. This intermediary gap allows the plunger to push the optical part forward effectively while preventing the optical part from slipping into dangerous gaps or being pinched

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent applies preliminary action by pre-forming the gap at a position where the optical part is likely to contact the plunger during injection. This preliminary preparation prevents breakage before it can occur, maintaining injection efficiency while ensuring safety

Inventive Principle:
Principle #10Preliminary action

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

This configuration allows for safe and effective insertion of the intraocular lens, reducing the risk of breakage and postoperative complications, and minimizing surgical time by ensuring proper positioning of the lens within the eye.

Implementation Method 1

the asperities provide friction to restrain the lens from entering the gap between the plunger and the injector wall

Methodology Applied
Scientific EffectFriction: Friction

Data Source

PatentEP2364673B1Intraocular lens injection instrument
Publication Date: 2015.12.02 NIDEK CO LTD
  • EP2364673B1 patent drawingFigure 1~2B
  • EP2364673B1 patent drawingFigure 3A~3B
  • EP2364673B1 patent drawingFigure 4A

AI summary

An intraocular lens injection instrument (10) for injecting an intraocular lens (IOL) (1, 1a) including an optical part (2) and support parts (3) into an eye by folding the IOL, comprises: a cylindrical body part (30) provided, at its front end, with an injection tubular part (20) configured to inject the IOL into the eye through an incision formed in the eye and including a setting part (22) in which the IOL is to be set; and a plunger (40, 40b-40e) for pushing the IOL out of the injection tubular part, the plunger being placed in the cylinder body part to be movable in an axial direction of the cylinder body part and having a tip portion (44), characterized by a part of an outer peripheral region of the plunger is formed with asperities (RF, RF2-RF6, G) to generate a predetermined frictional force by contact with the IOL, the predetermined frictional force being larger than a frictional force generated in the other part of the outer peripheral region of the plunger by contact with the IOL.