ArticleEffect of hydrodynamic parameters on corneal endothelial cell loss after phacoemulsificationBaradaran-Rafii, Alireza MD; Rahmati-Kamel, Mohsen MD; Eslani, Medi MD∗; Kiavash, Victoria MD; Karimian, Farid MD Author Information Form the Department of Ophthalmology and Ophthalmic Research Center, Labbafinejad Medical Center, Shahid Beheshti University (MC) (Baradaran-Rafii, Rahmati-Kamel, Kiavash, Karimian) and School of Medicine, Medical Sciences/University of Tehran (Eslani), Tehran, Iran ∗Corresponding author: Medi Eslani, MD, Labbafinejad Medical Center, Boostan 9 Street, Pasdaran Avenue, Tehran 16666, Iran. E-mail: [email protected] Submitted: November 10, 2008. Final revision submitted: December 17, 2008. Accepted: December 17, 2008. No author has a financial or proprietary interest in any material or method mentioned. SymbolFirst author:Symbol: No Caption available.Alireza Baradaran-Rafii, MD Labbafinejad Medical Center, Shahid Beheshti University (MC), Tehran, Iran Journal of Cataract & Refractive Surgery: April 2009 - Volume 35 - Issue 4 - p 732-737 doi: 10.1016/j.jcrs.2008.12.017 Buy Metrics Abstract PURPOSE: To evaluate the effect of power, vacuum, and flow rate on endothelial cell loss after phacoemulsification. SETTING: Labbafinejad Medical Center Medical Center, Tehran, Iran. METHODS: In a prospective randomized clinical trial, phacoemulsification was performed in 2 groups (high vacuum and low vacuum) with 3+ nuclear sclerosis. The stop-and-chop technique was used with the Sovereign machine. Machine parameters during the chop stage were vacuum 400 mm Hg in the high-vacuum group and 200 mm Hg in the low-vacuum group and flow rate, 40 cc/min and 20 cc/min, respectively. Endothelial cell density preoperatively before and 1, 6, and 12 weeks postoperatively were compared. RESULTS: Each group comprised 30 eyes. The mean US power was 9.2% ± 4.3% (SD) in the low-vacuum group and 13.1% ± 4.6% in the high-vacuum group (P = .001) and the mean phaco time, 1.28 ± 1.0 minutes and 0.88 ± 0.6 minutes, respectively (P = .04). Total US energy and total fluid consumed were similar between groups. After 12 weeks, the mean endothelial cell loss was 9.0% ± 4.0% in the low-vacuum group and 9.6% ± 4.6% in the high-vacuum group (P = .6). There was a relationship between total US energy and endothelial loss (P<.001); however, total fluid volume was not a significant predictor (P = .19). CONCLUSIONS: Vacuum level did not have a significant effect on total US energy or total fluid consumed during phacoemulsification. There was a strong relationship between total US energy and endothelial cell loss but not between total infused fluid and endothelial cell loss. © 2009 by Lippincott Williams & Wilkins, Inc.