Comparison of 2% and 3% sodium hyaluronate in phacoemulsification surgery

Erkan Tırak: Comparison of 2% and 3% Sodium Hyaluronate in Phacoemulsification Surgery. Medical Specialty Thesis, Bolu, 2009. Taking into consideration the various rheologic properties, different VEMs are currently preferred by surgeons in cataract surgery. Not many studies comparing the different concentrations of VEMs are found in the literature. Regarding this, we aimed to evaluate the efficacy and complications of 2% and 3% concentrations of sodium hyaluronate during and in the early postoperative period of phacoemulsification surgery.Fifty cases known to have no ophthalmological and/or systemic disease were included in the study. Two groups of 25 patients were formed according to 3% VEM (Group 1) and 2% VEM (Group 2) usage in phacoemulsification surgery. During surgery, surgeon evaluated passage of VEM from the cannula, escape of VEM from the anterior chamber, pupil dilatation during capsulorhexis, need of removal of VEM before hydrodissection, visualization during surgery, presence of iris prolapse or iris damage, and ease of VEM aspiration. At the 6th and 24th postoperative hours, two groups were compared for biomicroscopic examination, intraocular pressure, necessity of antiglaucomatous medication or removal of anterior chamber fluid through the corneal incision for intraocular pressure control, EFT, corneal edema, and central corneal thickness.It was observed that although passage of 3% VEM in Group 1 was more difficult compared to 2% in Group 2 at a statistically significant level (p<0.01), it escaped less at a statistically significant level (p<0.01) from the anterior chamber. For those patients with medium or poor pupil size, it permitted satisfactory pupil dilatation for capsulorhexis at a statistically significant level (p<0.05); and statistically significant less iris damage occurred (p<0.05). In the 2% VEM group, removal of VEM before hydrodissection was less necessary at a statistically significant level (p<0.05). No statistically significant difference was observed between the two groups for iris prolapse (p>0.05), ease of aspiration (p>0.05), and visualization during surgery (p>0.05). There was no statistically significant difference between the EFT of two groups. At the 6th and 24th postoperative hours, biomicroscopic examination revealed that the corneal edema (p<0.02, p=0.02, respectively) and the central corneal thickness were less in Group 1 at a statistically significant level (p<0.05, p=0.05, respectively). On the other hand, intraocular pressure levels at the 6th and 24th hours were significantly higher (p<0.01, p<0.01, respectively) in the 3% VEM group than in the 2% VEM group, and the necessity of antiglaucomatous medication (p<0.02, p=0.02, respectively) and removal of fluid through anterior chamber (p<0.01, p=0.01, respectively) for reduction of intraocular pressure was higher at a statistically significant level.In conclusion, in cataract surgery, although 3% VEM causes higher early postoperative intraocular pressure, it was observed to be more advantageous over 2% VEM since it provides a more stable anterior chamber, safer capsulorhexis, better endothelium protection, and less risk of complication.Key Words: Viscoelastic material, Sodium Hyaluronate, Phacoemulsification.