Corneal densitometry and its association with cumulative dissipated energy after phacoemulsification

To evaluate corneal densitometry after cataract surgery and its association with cumulative dissipated energy (CDE). Ninety-nine eyes of 74 patients who underwent uncomplicated phacoemulsification with intraocular lens (IOL) implantation surgery were included in this retrospective study. Examinations were conducted at baseline and 1 and 3 months after phacoemulsification. Corneal densitometry (CD) and 10-mm corneal volume (CV) measurements were obtained from corneal topography (Pentacam, Oculus, Wetzlar, Germany). The mean CV values increased significantly at the 1 and 3 months after surgery compared to baseline value (p<0.05). The mean CD values increased significantly at 1 month after surgery compared to baseline level for total diameter and all corneal annular zones except zone 2 and zone 3 in the anterior corneal layer (p<0.05). There was a positive correlation between CDE and the change in CD values in zone 3, zone 4 and total diameter in both the anterior and central corneal layers from baseline to 1 month after surgery (r=0.221, r=0.235, r=0.224, r=0.203, r=0.246, r=0.224; for all p<0.05, respectively). Corneal densitometry increased at different depths and layers of the cornea at 1 month after surgery, but returned to baseline values at 3 months after surgery. No correlation was found between CDE and change in CV values from baseline to 1 and 3 months after surgery. There was a positive correlation between CDE and the change in CD values in the peripheral 6-12 mm zone and total diameter within the anterior and central layers of cornea. The lack of endothelial cell count was a significant limitation of our study and limits the ability to differentiate between transient corneal edema and permanent endothelial cell loss as possible causes of postoperative densitometric changes.