Abstract
Purpose: :
VisthesiaTM is an ophthalmic viscosurgical device (OVD) which has 1% lidocaine and 1.5% sodium hyaluronate and topical 3% sodium hyaluronate with 2% lidocaine for corneal anesthesia. This technique of anesthesia is known as viscoanesthesia. The aim of the study was to evaluate the anesthetic effect and security of this OVD in cataract phacoemulsification.
Methods: :
Prospective, longitudinal, experimental, group randomized study performed at Ophthalmology Institute "Fundación Conde de Valenciana" in Mexico City. A total of 32 eyes with related aged cataract were included in two groups: viscoanesthesia with 1% lidocaine/1.5% sodium hyaluronate viscoelastic (VisthesiaTM, N=16) vs.peribulbar block anesthesia with 2%lidocaine/0.75% bupivacaine and a 1.6% sodium hyaluronate viscoelastic (Amvisc plus TM,N=16). Two surgeons realized all surgeries. Endothelial cell counts were measured at baseline and 30 days postoperatively. Pain was subjectively evaluated by patients using a visual analog pain scale (0-10).
Results: :
Kolmogorov-Smirnov showed a normal distribution of pre- and intraoperative variables of the study. All surgeries were uneventful with no intraoperative complications, only one patient of peribulbar block group had a hemorrhage in the site of application. Patients receiving viscoanesthesia had a mean pain score of 1.50±1.6 (0 to 5) compared to 1.56±2.5 (0 to 9) for patients receiving peribulbar block (p=0.405). Postoperatively endothelial cell loss at 1 month was greater for patients receiving VisthesiaTM (12.5%, endothelial count preoperatively 2741±332 mm2 and postoperatively 2399±402 mm2, p<0.05) than for those receiving the 1.6% sodium hyaluronate viscoelastic (1.4%, endothelial count preoperatively 2578±346 mm2 and postoperatively 2541 ±834 mm2, p>0.05).The surgeons reported a better ocular control with the use of peribulbar block.
Conclusions: :
The results from the visual analog pain scale were comparable between groups, showing that Viscoanesthesia provides similar pain relief to peribulbar block. Specular microscopy performed at 30 days postoperatively showed a significant loss of endothelial cells in viscoanesthesia group compared with control group. We need more patients and a long term follow up to verify this results, previous studies have shown controversial results.
Clinical Trial: :
Conde de Valenciana, CC-026-2011
Keywords: cataract • treatment outcomes of cataract surgery • drug toxicity/drug effects