Posters

Percent aqueous volume loss associated with post occlusion break surge in 4 phacoemulsification/aspiration systems

Poster Details

First Author: D. Fanney UNITED STATES

Co Author(s):    K. Miller   C. Aravena   A. Thorne   D. Dyk           

Abstract Details

Purpose:

To evaluate the percent aqueous volume loss associated with occlusion break surge in 4 current-generation phacoemulsification/aspiration (PEA) systems under varying vacuum limits and target intraocular pressures

Setting:

University of California - Los Angeles (UCLA) and Alcon Laboratories Lake Forest, CA

Methods:

A test apparatus eye model with a piston controlled by 3 springs calibrated to mimic the compliance of the normal human eye was used to model the anterior chamber. The PEA systems tested included the Alcon Centurion, AMO Signature White Star, DORC EVA, and B&L Stellaris PC. Occlusion breaks were initiated at vacuum limits of 200, 300, 400, 500, and 600 mmHg using a target intraocular pressure of 55 mmHg. The percent aqueous volume loss at each occlusion break was calculated using an average phakic eye volume of 250 µL.

Results:

Occlusion break surge volumes varied from 16 to175 µL. The test apparatus eye model collapsed at just above 500 mmHg on the DORC machine and above 350 mmHg using the B&L machine. Higher vacuum limits could not be tested. The corresponding percent aqueous volume losses ranged from 6.5 to 70%. The magnitude of the occlusion break surge response increased with each 100-mmHg increment in vacuum limit. The Alcon Centurion had the lowest surge response across all vacuum limits.

Conclusions:

Post occlusion break surge volumes vary greatly among the different PEA systems due to variable intrinsic compliance. Severe chamber shallowing may occur using some systems if occlusion is broken at a high vacuum limit.

Financial Disclosure:

One or more of the authors is employed by a forNONEprofit company with an interest in the subject of the presentation, One or more of the authors research is funded, fully or partially, by a company producing, developing or supplying the product or procedure presented