Abstract
Purpose: :
Fluid gas exchange is one of the useful techniques for vitreous surgery. However in case of the eye inserted intraocular lens (IOL), condensation is occurred at posterior surface of IOL after fluid to gas exchange and it interfere the visibility of operation field. The purpose of this study is analysis of the frequency and size of condensation using different materials of IOL in vitro.
Methods: :
To develop condensations reproducibly, precisely model-eye was prepared. The environment of model eye cavity was set to 35degree, 97% humidity and 30mmHg intraocular pressure. PMMA (UV-60SB: HOYA), silicone (AQ110: Canon) and acrylic (VA-70AD: HOYA) IOLs were prepared. To analyze the characteristics of each material, contact angles were measured (Drop Master DM500: Kyowa Interface Science) before the experiments. Each IOL was fixed to an anterior chamber in the model eye, and then condensations were caused with dropping 25 degrees distilled water on the anterior surface of IOL. The 10 water drops from each IOL were randomly chosen and size of condensation was measured and averaged. And also the frequency of condensation was contained in unit area (500µ square) which was chosen randomly. Tukey-Kramer was used for statistical analysis.
Results: :
Contact angles of IOL were 74.6 ° in PMMA, 85.7 ° in acrylic and 112.8 ° in silicon respectively. The sizes of condensation were 177 ± 30µm in PMMA, 140 ± 21µm in acrylic and 91 ± 11µm in silicon. The frequencies of condensation were 11.8 ± 1.6 in PMMA, 17.4 ± 2.8 in acrylic and 28.6 ± 2.1 in silicone. The frequency was statistically significant high in silicone IOL (P< .01).
Conclusions: :
The size and frequency of condensation is different dependent with each IOL. The differences of contact angle may cause these different frequency and form of condensations.
Keywords: intraocular lens • vitreoretinal surgery