Corneal Endothelium Evaluation After Phacoemulsification With Continuous Anterior Chamber Infusion

Abstract
To determine if the use of continuous anterior chamber infusion (CACI) during conventional phacoemulsification can damage the corneal structure by adding an additional hydrodynamic stress to the corneal endothelium intraoperatively and to use this option routinely in small-incision phacoemulsification to soften its learning curve. We performed a prospective, interventional, case series of patients with cataract who underwent phacoemulsification. Patients were previously classified into 2 groups based on whether CACI was used (group 2) intraoperatively or not (group 1). Pachymetry and endothelial cell (EC) density were evaluated before and after surgery, and data were compared between the 2 groups. Eyes with values of EC density less than 1000 cells/mm or showing previous corneal structural alterations were excluded from the study. Sixty-seven eyes were included in our study from September 2002 to January 2003. Group 1 included 31 eyes (mean pachymetry 520.4 microm and EC density 2883), and group 2 included 36 eyes (mean pachymetry 519.0 and EC density 2627). Multivariate analysis of postoperative data following a multiple regression model showed an increase in pachymetry for both groups at 24 hours after surgery that progressively diminished until the last visit 4 weeks postoperatively, and no statistically significant differences were found between the groups. EC density displayed an abrupt loss for both groups, especially for group 2, that reached statistical significance at day 7 after surgery (P = 0.020). EC density experienced an increase for both groups in follow-up visits, and it was not statistically different at last postoperative control (P = 0.361). : The trend in modern cataract surgery is to reduce postoperative ocular trauma, and this can be achieved by small-incision phacoemulsification. But it requires a learning curve that we believe can be softened by using some surgical maneuvers such as continuous anterior chamber infusion, which minimizes the risk for anterior chamber collapse during the intervention. Comparing postoperative pachymetry and EC density between group 1 and 2, we found that the use of CACI does not add any additional damage to corneal structures because the initial statistically significant EC loss at day 7 postoperatively has a prompt recovery in subsequent visits, and then the EC loss remains similar in both groups. Transition from conventional to bimanual phacoemulsification can be simplified by using CACI, and it does not increase postoperative corneal damage.