Association of Cumulative Dissipated Energy and Postoperative Foveal Thickness among Patients with Age-related Cataract who Underwent Uncomplicated Phacoemulsification
Joel M. Perez, MD, Manuel Benjamin B. Ibanez IV, MD, Sherman O. Valero, MD
Purpose/Objective:
Cumulative dissipated energy (CDE) is a phacoemulsi cation unit parameter designed to monitor the amount of energy delivered during phacoemulsi cation. Studies have already shown that lower CDE levels have better surgical outcomes, speci cally in corneal recovery. However, few literature exists regarding the correlation between CDE and foveal thickness.
Methods:
In this prospective study, subjects with agerelated cataract underwent cataract surgery by phaco emulsi cation. Central sub eld thickness (CST), cube volume (CV), and cube average thickness (CAT) of the macula were measured by spectraldomain optical coherence tomography (OCT) at three separate timepoints: preoperative, 1 day, and 14 days after cataract surgery. To determine the correlation between parameters, Pearson’s correlation coef cients and degree of association, and coef cient of determination (r2) were used.
Results:
One hundred eyes from 93 subjects were analysed. Preoperatively, mean CST was 247.71 ± 21.44 μm, CV was 9.38 ± 0.82 mm3, and CAT was 262.94 ± 22.15 μm. At 12.42 + 11.05 of mean CDE exposure, the fovea increased in thickness in all measured parameters. The relationship between CDE and the change in foveal thickness values from baseline to postoperative Day 1 and Day 14 were examined. The correlation coef cients obtained for CST, CV, and CAT had low association to CDE. Furthermore, only the correlation coef cients of the difference between baseline and Day 1 of CST, and the difference between baseline and Day 14 observations of CV were signi cant (0.279 and -0.206, p=0.005 and p=0.040, respectively) but still with a low degree of association.
Conclusion:
There is a low, signi cant, direct association of the difference of CST on Day 1 from baseline with CDE, and a low, signi cant, indirect association of the difference of CV on Day 14 from baseline with CDE after routine phacoemulsi cation.
Keywords: Phacoemulsi cation, Cumulative dissipated energy, Foveal thickness, OCT, Age-related cataract, Macular edema