Abstract
Purpose :
A relatively large size aspiration tubing in fluidics pack could result in increased flow during cataract surgery when using Venturi mode in a gravity-based phacoemulsification system, causing chamber instability and compromising the balance of holdability and followability. New fluidics packs using small-bore, dual-durometer aspiration tubing were constructed. This study will evaluate aspiration flow of the newly constructed fluidics packs with a new phacoemulsification machine in Venturi mode in a laboratory setup.
Methods :
The inner layer of the aspiration tubing of the new fluidics packs uses a stiffer material with a smaller inner diameter than existing products, while the outer layer is soft and maintains flexibility. These packs were tested with a Phaco handpiece and three different Phaco tips (19, 20, and 21 Gauges) in a newly available phacoemulsification machine set to Venturi mode, along with existing packs as the control arm. A glass beaker filled with deionized (DI) water was placed on a weight scale with water level started for each test run at the same height as the vacuum sensor in the Phaco machine. The Phaco tip was submerged in the DI water and the Venturi vacuum was applied for 15 seconds. The loss of the water in the beaker was measured for calculation of the aspiration flow rate with Venturi vacuum ranging from 100 to 600 mmHg in 100 mmHg step. Additionally, the effect of viscous fluid (a water/glycerin mixture) on the aspiration flow rate was also investigated with the 20 Gauge Phaco tip.
Results :
The relationship between the aspiration flow and vacuum was nonlinear. The new fluidics packs produced smaller aspiration flow rates than the existing packs, with a 20% reduction for the 20 Gauge Phaco tip configuration. The differences were statistically significant (p < 0.01). At least 30% higher vacuum can be used with the new fluidics packs to achieve the same flow rate compared to the existing packs. Using viscous fluid also lowered the flow rate further.
Conclusions :
In laboratory test, new fluidics packs with small-bore, dual-durometer aspiration tubing produced markedly smaller aspiration flow rates compared to the existing packs at the same vacuum settings in Venturi mode. The use of the new fluidics packs provides a better flow and vacuum control for improved chamber stability and a more balanced followability and holdability during phacoemulsification.
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.