Phacoemulsification Tip Geometry for Lateral Displacement Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Phacoemulsification tips experience significant lateral displacement during ultrasonic torsional vibration, which can lead to inefficiencies and complications during cataract removal procedures, as existing tip geometries do not effectively minimize shaft displacement while maximizing distal end point displacement.
Innovation Solution
A phacoemulsification tip with a shaft and cutting edge portion featuring at least two bends, configured to achieve lateral displacement along its length that is less than 5% to 25% of the distal end point displacement, optimized through geometric modeling and physical testing to reduce shaft displacement while increasing twisting vibrations at the distal end point.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional tip geometries are used during ultrasonic torsional vibration, then the distal end point achieves sufficient displacement for lens emulsification, but the shaft experiences significant lateral displacement causing inefficiencies and complications
Solution Approach 1:
The tip is segmented into distinct geometric zones including a shaft portion, a transition zone with first and second bends, and a distal cutting portion. This segmentation allows each zone to serve different functions: the shaft provides structural support while the bends act as compliance elements that isolate lateral displacement, and the distal portion maintains high displacement amplitude for effective lens emulsification.
Solution Approach 2:
Different portions of the tip are given different geometric properties optimized for their specific functions. The shaft has a geometry optimized for minimal lateral displacement, while the distal end maintains geometry optimized for maximum displacement amplitude. The transition zone with controlled bends provides localized flexibility to decouple the motion characteristics of different segments.
2Productivity
If tip geometry is optimized to maximize distal end point displacement, then lens emulsification efficiency improves, but shaft lateral displacement increases causing complications
Solution Approach 1:
The first and second bends in the transition zone serve as intermediary elements that decouple the motion between the shaft and distal end point. These bends act as compliance features that allow the distal portion to achieve high displacement amplitudes for effective lens emulsification while isolating the shaft from excessive lateral displacement that would cause surgical complications.
Solution Approach 2:
The tip geometry introduces dimensional complexity through three-dimensional bending in the transition zone. Rather than a simple linear structure, the first and second bends create a spatial configuration that selectively transmits and amplifies distal end motion while filtering out harmful lateral shaft displacement, effectively using geometric dimensioning to resolve the contradiction.
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 optimized tip geometry reduces lateral displacement along the shaft, enhancing the precision and efficiency of cataract removal by maximizing twisting vibrations at the distal end point, thereby improving the phacoemulsification process.
Implementation Method 1
a thin phacoemulsification tip may be inserted into the diseased lens and vibrated ultrasonically
Data Source
AI summary
In various embodiments, a phacoemulsification tip may include a shaft and a cutting edge portion having at least a first and second bend. The geometry of the tip may be configured to result in a lateral displacement (ux), perpendicular to the shaft during torsional vibration of the tip at frequencies between 10 kHz and 60 kHz, of less than approximately 5% to 25% (e.g., 15%) of the lateral displacement at the distal end point of the tip throughout a portion of the shaft extending from the end of a conical portion of the tip through to the first bend in the cutting edge portion of the tip. Software and/or physical modeling may be used to determine the tip geometry.