Surface Of Acrylic Intraocular Lenses Research Articles

Studying the Interaction of Viteral Substitutes with the Surface of Acrylic Intraocular Lenses

Purpose of the study: In vitro to study the degree of adhesion of vitreous substitutes, such as silicone oil of various viscosities and perfluorodecalin (PFOS), to hydrophobic acrylic polymer IOLs and evaluate the interaction of vitreous substitutes with the model MIOL-Soft-23 in the clinic. Material and methods. IOLs of the model MIOL-Soft-23 were taken for the experiment. MIOL-Soft-23 are included in the RPR-20 set. IOL of the model MIOL-Soft-23 is made by photopolymerization from a biocompatible spatially cross-linked hydrophobic acrylic polymer based on oligomers and monomers of the methacrylic series with filters in the ultraviolet region of the spectrum from 19 to 23 D. For the experiment, silicone oils of different viscosities were taken: RS-OIL 2000 (Alchimia), SIL-5000-S (DORC), Oxane 5700 (Bausch & Lomb), PFOS (perfluorodecalin) Dk-line (Bausch & Lomb). Also, saline sodium chloride 0.9 % (Solofarm) was used. Results. Revealed a decrease in the degree of silicone adhesion to the surface of acrylic hydrophobic IOLs as the temperature rises, not less than 1.5 %. The absence of dependence of the degree of adhesion on the degree of viscosity of silicone oil was confirmed, which corresponds to the literature data. For the first time, the average percentage of adhesion of perfluorodecalin to the IOL surface data were obtained, in particular, the MIOL-Soft-23 model. The range of values ranged from 0.7 to 7.2 %. The average coverage percentage is 1.9 ± 1.3 % (exposure at 37 ± 1 °C for up to 14 days) and 3.4 ± 1.5 % (exposure at room temperature for up to 14 days). This confirms the need for careful intraoperative monitoring of the completeness of removal of PFOS droplets from the IOL surface. Conclusion. The presence of the risk of adhesion of residual drops of silicone oil and PFOS to the surface of the IOL necessitates careful intraoperative control of the completeness of the removal of vitreous body substitutes, as well as further search for the best ways to eliminate this complication. The conducted complex of studies makes it possible to recommend the use of IOL model MIOL-Soft-23 in complicated cases of vitreal surgery.

Effect of ophthalmic solution components on acrylic intraocular lenses

To investigate the effect of ophthalmic solution components on the surface of acrylic intraocular lenses (IOLs). Department of Opthalmology, Showa University School of Medicine. Measurement of the contact angles of ophthalmic solutions on 3 acrylic IOLs was performed. The solutions were diclofenac sodium (Diclod), bromfenac sodium (Bronuck), betamethasone phosphate (Rinderon), dibekacin sulfate (Panimycin), polysorbate 80 (Tween 20), benzalkonium chloride, chlorobutanol, methylparahydroxybenzoate, and propylparahydroxybenzoate. The IOLs were incubated at 35 degrees C for 2 weeks in undiluted ophthalmic solutions and in 1:10 dilutions of ophthalmic solution components. The IOLs were sectioned and observed by scanning electron microscopy. The contact angle of Diclod and Bronuck solutions was the smallest. The contact angle of Rinderon and Panimycin was similar to that of distilled water. Scanning electron microscopy examination of IOLs incubated in ophthalmic solution components showed intralenticular changes. The IOLs immersed in ophthalmic solutions did not show any change, even after extended incubation. The chemical components of ophthalmic solutions, such as surfactants and solvents, permeate acrylic IOLs, suggesting the potential for long-term adverse effects of eyedrops in pseudophakic eyes.

Active oxygen processing for acrylic intraocular lenses to prevent posterior capsule opacification

To evaluate active oxygen processing on the surface of acrylic intraocular lenses (IOLs) to prevent secondary posterior capsule opacification (PCO). Department of Ophthalmology, Dokkyo Medical University School of Medicine, Mibu City, Tochigi, Japan. Acrylic IOLs were prepared, and ultraviolet (UV)/ozone (UV/O3) or argon plasma was irradiated to the surface of the IOLs. Elemental analysis (electron spectroscopy for chemical analysis [ESCA]) of the IOL surfaces was performed to confirm surface modification. Changes produced by UV/O3 or argon plasma treatment were examined for fibronectin and lens epithelial cell (LEC) adhesion. To evaluate the PCO prevention by treated IOLs, 8-week-old albino rabbits were used. The rabbit eyes randomly had phacoemulcification and implantation of 3 different IOLs: the UV/O3-treated IOLs, argon plasma-treated IOLs, and the control IOLs. After 2 weeks, the rabbits were killed and their globes were dissected and fixed using formaldehyde 10%. The PCO was observed using light microscopy (DX51, ORIMPUS) after hematoxylin and eosin staining. Comparison of IOL surface composition by ESCA showed an increase in nitrogen content and hydroxyl substitute and carboxyl substitute groups on surfaces of treated IOLs. The fibronectin adhesion and the LEC adhesion on the UV/O3-treated and argon plasma-treated samples were increased. In the untreated group, there was statistically significant inhibition of PCO formation in the UV/O3-treated and argon plasma-treated groups. Active oxygen processing and argon plasma irradiation on the surface of IOLs was effective in preventing secondary PCO after cataract surgery.

In vitro study of antibiotic effect on bacterial adherence to acrylic intraocular lenses

Implantation of artificial intraocular lenses into the eye during ophthalmic surgical procedures ensures an unliving surface on which bacterial pathogens may attach and form biofilms. Despite antibiotic treatment bacteria growing in biofilms might cause inflammation and serious complications. In this study the adhesive ability of 7 Staphylococcus aureus and 11 coagulase-negative Staphylococcus (CNS) strains to the surface of acrylic intraocular lenses had been examined by the ultrasonic method. In untreated cases adhesion of the S. aureus and CNS strains did not differ significantly. We could not demonstrate significant differences between the adhesive ability of the standard strains and the clinical isolates. In this study a single – 60 min long – antibiotic (ciprofloxacin and tobramycin) treatment had been applied, that correlate well with the single or intermittant antibiotic prophylaxis of patients. Ciprofloxacin administration was able to reduce significantly the number of attached cells on the surface of acrylic lenses both in the case of S. aureus and CNS strains. Dependence of the effect from concentration could also be demonstrated. Tobramycin treatment was able to inhibit significantly the attachment of S. aureus cells. Despite the debate on antibiotic prophylaxis we presented in our experiments that a single antibiotic administration can decrease the attachment of bacterial cells to the surface of acrylic intraocular lenses, and might be effective in the prevention of postoperative endophthalmitis, that is a rare but serious complication of ophthalmic surgery.

Light Scattering Observed on the Surface of Acrylic Intraocular Lenses Ten Years after Implantation

To report the long-term status of acrylic intra-ocular lenses. We describe two cases of increased light scattering on the surface of acrylic intraocular lenses ten years after implantation. The scattering was non-symptomatic and visual acuity was normal. Biomicroscopy and a Scheimpflug photography system showed that the scattering apparently derived from the anterior surface of the lens, but no deposit or membranous structure was observed on the lens surface. Surface scattering from acrylic intra-ocular lenses is a new finding in long-term observations. A possible etiology may be structural changes of the internal polymer.

Effect of Aminoglycosides (Sub-MICs) on Adherence of Coagulase-Negative Staphylococci to Intraocular Lens Surface

The authors evaluated the in vitro effects of subinhibitory concentrations (sub-MICs) of aminoglycosides (gentamicin, netilmicin and tobramycin) on the adherence of coagulase-negative staphylococcus to intraocular lens (PMMA, acrylic and heparin) surface. The five strains of coagulase-negative Staphylococcus epidermidis used (S. epidermidis IMe7, IMe11, IMe27, IMe29 and IMe31) were tested for their ability to produce slime. The minimum inhibitory concentrations (MIC) indicated high susceptibility in vitro to the antibiotics and homogeneous values. The adhesion tests without antibiotics (K1, K2 and K3) for every time considered (30 min, 60 min and 180 min) and for all examined strains showed more constant adhesive activity on the surface of acrylic intraocular lens (IOLs) than on the surface of heparin IOLs. The aminoglycosides tested were able to reduce adhesivity by coagulase-negative S. epidermidis slime to the IOL surfaces, even at sub-MICs. The documentation obtained by scanning electron microscope shows the growth of a strain of S. epidermidis IMe11 after 180 minutes of contact which remains adherent to the surface of the acrylic IOLs.