Viscoat versus Visthesia during phacoemulsification cataract surgery: corneal and foveal changes

Abstract

BackgroundOphthalmic viscosurgical devices (OVDs) are widely used in phacoemulsification cataract surgery to maintain adequate intraocular space, stabilize ocular tissue during the operation and decrease the possible damage of the corneal endothelium. Our study has the purpose to compare the corneal and foveal changes of Viscoat and Visthesia in patients undergoing uneventful phacoemulsification cataract surgery.MethodsParticipants in our study were 77 consecutive patients, who were randomized into two groups based on type of OVD used during phacoemulsification: Viscoat or Visthesia. All patients underwent a complete ophthalmological examination i.e., measurement of best corrected visual acuity (BCVA) by means of Snellen charts, intraocular pressure examination by Goldmann tonometry, slit lamp examination, fundus examination, optical coherence tomography, specular microscopy and ultrasound pachymetry preoperatively and at three time points postoperatively (day 3, 15, 28 postoperatively). The differences in baseline characteristics, as well as in outcomes between the two groups were compared by Mann-Whitney-Wilcoxon test and Student's t-test, as appropriate.ResultsIntraoperatively, there was no statistically significant difference in the duration of the ultrasound application between the two groups, while Viscoat group needed more time for the operation performance. It is also worthy to mention that Visthesia group exhibited less intense pain than patients in Viscoat group. Postoperatively, there was a statistically significant difference in central corneal thickness, endothelial cell count and macular thickness between the two groups, but BCVA (logMAR) did not differ between the two groups.ConclusionsOur study suggests that Viscoat is more safe and protective for the corneal endothelium during uneventful phacoemulsification cataract surgery, while Visthesia is in superior position regarding intraoperative pain. Patients of both groups acquired excellent visual acuity postoperative. Finally, this is the first study comparing OVDs in terms of macular thickness, finding that Visthesia cause a greater increase in macular thickness postoperatively than Viscoat, although it reaches normal ranges in both groups.

Prospective Randomized Study Comparing Combined Phaco-ExPress and Phacotrabeculectomy in Open Angle Glaucoma Treatment: 12-Month Follow-Up

“…Such a difference between the findings may result from the fact that, in our case, the impact of the operation combined with simultaneous phacoemulsification is taken into account. Damage to endothelial cells after cataract surgery itself is documented [ 30 – 35 ]. Inasmuch as the impact of glaucoma shunts on the cornea has been fairly well studied, there are no long-lasting and repeatable findings on other operating techniques.…”

Changes in corneal endothelium cell characteristics after cataract surgery with and without use of viscoelastic substances during intraocular lens implantation

“…At least one former publication reported a significant impact of different OVDs on foveal thickness after phacoemulsification and IOL implantation. 29 …”

Advances in cataract surgery

“…Another more recently developed device combines a cohesive OVD and ancillary lidocaine. Recent studies continue to demonstrate varying results as one study found a significantly higher mean ECL in patients receiving the combination device (9.60%) compared with those receiving lower viscosity dispersives (1.24%) during phacoemulsification, while another study found no significant difference between the two groups (11.8 and 9.1%, respectively) [50,51]. One study concluded that ECL rates with the combination device were comparable to those reported for similar OVDs, whereas another study found significantly higher ECL with the combination device when compared with the use of a dispersive OVD at the beginning of surgery and a cohesive OVD prior to intraocular implantation [48,49].…”