Phacoemulsification Needle Off-Axis Tip Torsional Wobble
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing phacoemulsification needles designed for longitudinal handpieces do not produce effective results when used with torsional handpieces, as they lack sufficient eccentric motion or 'wobble' necessary for efficient emulsification.
Innovation Solution
A phacoemulsification needle with a straight tip formed off-axis relative to the needle body, featuring an asymmetric configuration and a central aspiration passageway with a cross-sectional shape different from the needle body, enhances eccentric motion and torsional efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a traditional phacoemulsification needle with a straight tip aligned with the needle body axis is used, then the needle is compatible with longitudinal handpieces and has simple manufacturing, but it does not produce sufficient eccentric motion or 'wobble' when used with torsional handpieces, resulting in ineffective emulsification
Solution Approach 1:
The needle tip is deliberately positioned off-axis relative to the needle body axis, creating an asymmetric configuration. This asymmetry generates eccentric motion or 'wobble' during torsional oscillation, enabling effective emulsification with torsional handpieces while maintaining compatibility with longitudinal handpieces
2Productivity
If the needle tip is formed off-axis to create eccentric motion, then torsional emulsification efficiency is improved, but the manufacturing complexity increases due to asymmetric configuration
Solution Approach 1:
The off-axis tip configuration is manufactured using precision techniques such as swaging, crimping, or forming processes that can create the asymmetric geometry in a single step or integrated process, minimizing additional manufacturing complexity while achieving the required eccentric motion
3Productivity
If the aspiration passageway cross-sectional shape is made different from the needle body cross-section, then fluid dynamics and aspiration efficiency are improved, but manufacturing precision requirements increase
Solution Approach 1:
The aspiration passageway is given a different cross-sectional shape (e.g., oval or rectangular) compared to the needle body (e.g., circular) to optimize fluid dynamics and aspiration efficiency in the critical region where debris removal occurs, while the rest of the needle maintains a simpler geometry for ease of manufacture
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 off-axis tip design improves phacoemulsification results by creating sufficient 'wobble' during torsional motion, enhancing the efficiency of the needle when used with non-longitudinal handpieces, such as those providing rotational or torsional oscillation.
Implementation Method 1
Electrical energy is applied to vibrate the needle at ultrasonic frequencies in order to fragment the diseased lens into small enough particles
Implementation Method 2
handpieces that provide torsional oscillation of the phacoemulsification tip at frequencies of about 32,000 cycles/second
Data Source
AI summary
A phacoemulsification needle has a polygonally-shaped tip with an axis that is offset from the axis of the needle body. The material forming the tip is non-uniformly distributed, adding to the motion of the tip when it is vibrated torsionally. In one embodiment, the tip has tip wall segments of varying thicknesses. In another embodiment, the tip has a series of external ribs formed on the tip wall segments, on the wall segment, at the apex where adjacent wall segments meet, or both.