Session Title: Cataract II
Session Date/Time: Saturday 16/02/2013 | 08:30-11:00
Paper Time: 09:05
Venue: Hall 1
First Author: : P.Chaniecki POLAND
Co Author(s): : E. Stodolak Zych M. Rekas
Purpose:
To evaluate durability of different (hydrophobic and hydrophilic based materials) intraocular lenses (IOL), which were immersed in BSS solution. The degradation process was monitored by assessing changes in wet-ability of the IOL surface (contact angle measurement) and their surface free energy (ITF).
Setting:
Department of Opthalmology, 5th Military Hospital with Policlinic, Krakow, Poland. AGH - University of Science and Technology, Faculty of Materials Science and Ceramics, Department of Biomaterials, Krakow, Poland. Department of Ophthalmology, Military Institute of Medicine, Warsaw, Poland.
Methods:
Single IOL was incubated in BSS solution at 80°C. The degradation time (28 days) was calculated using equations presented in the literature [ISO 11979-5:2006 Ophthalmic implants – intraocular lenses – part 5]. The time corresponded to IOL changes taking place approximately after 5 years in in vivo conditions. Progress in degradation of the single IOL was observed by physicochemical methods. Surface state of the materials was characterised by the dynamic method of wetting angle determination (DSA 10 apparatus, Kruss, Germany). As measurement liquid ultra high quality (UHQ) water was used. Free surface energy was determined by Owens-Wendt method using double distilled UHQ water and Diiodomethane (Aldrich Chemical Co.). Surface microstructure was observed using an optical microscope (Nicon ZT400).
Results:
After 28 days of incubation most of the IOLs (8 types) had hydrophobic or hydrophilic surface. Only IOL covered with heparine (PolyLens BioVue) showed more hydrophobic properties. The surface free energy confirmed this observation i.e. dispersion component was much higher. These same effects i.e. decreased dispersion compound after 5 years of degradation was observed in the case of IOL with mixed hydrophobic and hydrophilic surface (CT-Zeiss). It suggested, that proteins and cells did not prefer surface with higher dispersion compound i.e. more hydrophilic. Glistening was observed in all examined IOLs.
Conclusions:
The presented method can be used for approximation of the degradation behaviour of IOLs. The results showed that all materials changed in in vitro conditions. Smaller effects of degradation were found in IOLs made of polymer which the surface showed mixed hydrophilic/hydrophobic characteristics or IOLs covered by heparine.
Financial Disclosure:
None
