Back-Loaded IOL Cartridge Haptic Orientation and Registration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional intraocular lens (IOL) cartridges face challenges in controlling the orientation and passage of IOLs, leading to potential damage and misalignment during insertion, due to difficulties in engaging the push-rod and managing the deformation of the optic and haptics within the cartridge.
Innovation Solution
The design includes a proximal opening with a peripheral slot that guides the leading haptic and deforms it across the optic, ensuring proper orientation and deformation within a holding area, and an asymmetrically located cutout for secure registration with the handpiece, allowing controlled passage through a hollow interior that narrows to facilitate folding and minimize push-rod contact.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Length of moving object
If the IOL is rolled inside the injection tube, then the IOL can be delivered through a small incision, but the orientation of the optic and haptic portions becomes difficult to control
Solution Approach 1:
The cartridge is divided into distinct functional zones: a load chamber for initial IOL placement, a peripheral slot for guiding the leading haptic, and a holding area for maintaining orientation during delivery. This segmentation allows each zone to perform its specific function, ensuring both compact delivery and precise orientation control.
Solution Approach 2:
The peripheral slot acts as an intermediary structure between the load chamber and the holding area. It specifically guides the leading haptic through a controlled path, ensuring proper orientation while allowing the optic to follow naturally. This intermediary element solves the orientation control problem without requiring complex active control mechanisms.
2Productivity
If force is applied to push the IOL through the injection tube, then the IOL can be delivered into the eye, but the push-rod may slip under or over the IOL or damage the optic
Solution Approach 1:
The peripheral slot is pre-configured to engage with the leading haptic before the push-rod applies force. This preliminary engagement ensures that when pushing begins, the IOL is already oriented correctly and the push-rod contacts the IOL at the proper position, preventing slippage and damage while maintaining efficient delivery.
3Ease of operation
If the proximal opening is made large to facilitate IOL insertion, then insertion is easier, but the IOL cannot be properly guided and deformed
Solution Approach 1:
The cartridge interior is segmented into a load chamber with a relatively large opening for easy insertion, followed by a peripheral slot that guides the leading haptic, and finally a holding area that maintains deformation. This segmentation allows the opening to be large for ease of operation while subsequent structures provide the necessary guidance and deformation control.
Data Source
AI summary
A rear-loaded injector cartridge for an intraocular lens (IOL) having a proximal opening that provides a haptic slot. The haptic slot receives a leading haptic of an IOL loaded therein, and temporarily retains the leading haptic while the optic of the IOL is inserted into a holding area of the cartridge. As the optic passes by, the leading haptic folds over the top of the optic, on its anterior side. The length of the haptic retention slot is sufficient to maintain the leading haptic in its anteriorly folded position while the IOL remains in holding area, typically while the cartridge is mated with a handpiece of the injector. The cartridge also has a rear or proximal cut out which advantageously keys with a similarly-sized rail on the handpiece so that the cartridge cannot be inserted in the wrong way.