Optical and material analysis of opacified hydrophilic intraocular lenses after explantation: a laboratory study

Background: The opacification of hydrophilic intraocular lenses (IOLs) is a very rare complication in terms of absolute numbers. We report on the analyses of opacified Euromaxx ALI313Y and ALI313 IOLs (Argonoptics, Germany) using light and scanning electron microscopy, X-ray spectroscopy and optical bench analysis. Methods: Opacified Euromaxx ALI313Y and ALI313 IOLs were explanted after patients presented with a decrease in visual acuity. The explants were sent to our laboratory and examined using light and scanning electron microscopy. The composition of the deposits was analysed using X-ray spectroscopy. The optical quality of the intraocular lens (IOL) was assessed using the OptiSpheric IOL PRO optical bench (Trioptics GmbH Wedel, Germany). Modulation transfer function (MTF) was measured at all spatial frequencies and United States Air Force (USAF) 1951 resolution target pictures were documented. Results: Macroscopically, the entire optic was opacified in all IOLs. Light and scanning electron microscopy revealed numerous fine, granular, crystalline-like deposits, which were always distributed in a line parallel to the anterior and posterior surfaces of the IOLs. X-ray spectroscopy could prove the deposits consisted of Calcium and Phosphate. Measurements in the optical bench showed deterioration of MTF values at all spatial frequencies and the USAF target pictures demonstrated a significant reduction of brightness as well as resolution with the opacified IOLs. Conclusions: The calcification of hydrophilic IOLs only occurs rarely. The exact chemical composition of the deposits can be assessed by means of X-ray spectroscopy. Optical quality analysis of the explanted Euromaxx ALI313Y and ALI313 IOLs showed significant reduction of MTF values, which was confirmed by USAF target pictures

In vitro optical quality measurements of three intraocular lens models having identical platform

Background: With recent advances in technology and introduction of new intraocular lens (IOL) models, surgeons today have the opportunity to choose from various optical designs, which can influence the postoperative quality of vision. In our laboratory study, we compared the optical quality of three different IOLs that use the identical platform and are produced by the same manufacturer. The study included two diffractive multifocal IOLs, a bifocal and a trifocal one, as well as a monofocal IOL. Methods: Three IOL models: monofocal CT ASPHINA 409 M, diffractive bifocal AT LISA 809 M, and diffractive trifocal AT LISA Tri 839MP (Carl Zeiss Meditec AG, Germany) were assessed for optical quality by measuring modulation transfer function (MTF) and Strehl Ratio (SR) values at pupil sizes of 3.0 and 4.5 mm on the OptiSpheric® IOL PRO (Trioptics GmbH, Germany). The United States Air Force (USAF) Target images were also recorded to comfirm the optical performance qualitatively. Results: For far focus at 50 lp/mm and 3.0 mm pupil size, MTF value of the monofocal lens (MTF = 0.798) was 1.8-fold and 2.1-fold better than the bifocal (MTF = 0.446) and the trifocal (MTF = 0.382) IOLs, respectively. For near focus, bifocal IOL (MTF = 0.265) was 1.4-fold better than trifocal IOL (MTF = 0.187), while for intermediate focus, the trifocal IOL (MTF = 0.148) was 1.7-fold better than the bifocal IOL (MTF = 0.086). For the same pupil size, total sum of light loss amounted to 5.2% for the monofocal, 16.0% for the bifocal and 6.0% for the trifocal IOL. For a larger pupil, the amount of light loss increased significantly for the multifocal IOLs. Conclusions: The monofocal IOL performed the best for far, the bifocal IOL for near and the trifocal IOL for intermediate focus. While the monofocal IOL created the least amount of light loss for both pupil sizes, the trifocal IOL created less than half the amount of light loss than the bifocal IOL for small pupil. For large pupil, however, less light scatter was observed for the bifocal than the trifocal IOL

Hydrophilic intraocular lens opacification after posterior lamellar keratoplasty - a material analysis with special reference to optical quality assessment

Background: Laboratory analysis and optical quality assessment of explanted hydrophilic intraocular lenses (IOLs) with clinically significant opacification after posterior lamellar keratoplasty (DMEK and DSAEK). Methods: Thirteen opacified IOLs after posterior lamellar keratoplasty, 8 after descemet stripping automated endothelial keratoplasty (DSAEK), 3 after descemet membrane endothelial keratoplasty (DMEK) and 2 after both DSAEK and DMEK were analysed in our laboratory. Analyses included optical bench assessment for optical quality, light microscopy, scanning electron microscopy (SEM) and energy dispersive X-Ray spectroscopy (EDS). Results: In all IOLs the opacification was caused by a thin layer of calciumphosphate that had accumulated underneath the anterior optical surface of the IOLs in the area spared by the pupil/anterior capsulorhexis. The calcifications lead to a significant deterioration of the modulation transfer function across all spatial frequencies of the affected IOLs. Conclusions: The instillation of exogenous material such as air or gas into the anterior chamber increases the risk for opacification of hydrophilic IOLs irrespective of the manufacturer or the exact composition of the hydrophilic lens material. It is recommended to avoid the use of hydrophilic acrylic IOLs in patients with endothelial dystrophy that will likely require procedures involving the intracameral instillation of air or gas, such as DMEK or DS(A)EK

In vitro comparative optical bench analysis of a spherical and aspheric optic design of the same IOL model

Background: To analyse objective optical properties of the spherical and aspheric design of the same intraocular lens (IOL) model using optical bench analysis. Methods: This study entailed a comparative analysis of 10 spherical C-flex 570 C and 10 aspheric C-flex 970 C IOLs (Rayner Intraocular Lenses Ltd., Hove, UK) of 26 diopters [D] using an optical bench (OptiSpheric, Trioptics, Germany). In all lenses, we evaluated the modulation transfer function (MTF) at 50 lp/mm and 100 lp/mm and the Strehl Ratio using a 3-mm (photopic) and 4.5-mm (mesopic) aperture. Results: At 50 lp/mm, the MTF values were 0.713/0.805 (C-flex 570 C/C-flex 970 C) for a 3-mm aperture and 0.294/0.591 for a 4.5-mm aperture. At 100 lp/mm, the MTF values were 0.524/0.634 for a 3-mm aperture and 0.198/0.344 for a 4.5-mm aperture. The Strehl Ratio was 0.806/0.925 and 0.237/0.479 for a 3-mm and 4.5-mm aperture respectively. A Mann–Whitney U test revealed all intergroup differences to be statistically significant (p < 0.01). Conclusion: The aspheric IOL design achieved higher MTF values than the spherical design of the same IOL for both apertures. Moreover, the differences between the two designs of the IOL were more prominent for larger apertures. This suggests that the evaluated IOL provides enhanced optical quality to patients with larger pupils or working under mesopic conditions

Injectable 0.19-mg fluocinolone acetonide intravitreal implant for the treatment of non-infectious uveitic macular edema

Background: A retrospective observational clinical study to evaluate the safety and effectiveness of the injectable 0.19-mg fluocinolone acetonide intravitreal implant (ILUVIEN) in the treatment of non-infectious uveitic macular edema. Results: Data are presented from eight patients (11 eyes) with non-infectious uveitic macular edema who were treated with a 0.19-mg fluocinolone acetonide implant. Nine out of 11 eyes were pseudophakic prior to implantation of fluocinolone acetonide implant, and both phakic eyes required cataract surgery during the follow-up period (the median follow-up was 19 months; range, 8–42 months). Effectiveness and safety were assessed from changes in central retinal thickness (measured using spectral domain optical coherence tomography), corrected distance visual acuity, uveitic activity, and intraocular pressure. The main outcome measures were changes in central retinal thickness, corrected distance visual acuity, uveitic activity, and intraocular pressure. In 11/11 eyes, central retinal thickness improved between months 1 and 3. The mean maximum decrease of central retinal thickness throughout the follow-up period was 168 ± 202 μm (± standard deviation). Nine out of 11 eyes showed an improvement in corrected distance visual acuity (between + 1 and + 8 lines), and 2/11 eyes lost corrected distance visual acuity (− 1 and − 3 lines, respectively). Nine out of 11 eyes presented with inactive inflammation during the follow-up period, and in 1/11 eyes, there was a relapse at month 42. Four out of 11 eyes presented with a relapse of macular edema between months 3 and 8. The mean increase in intraocular pressure was 2.1 ± 4.7 mmHg. Nine eyes were pseudophakic prior to implantation of the injectable fluocinolone acetonide intravitreal implant. Both phakic patients developed a cataract that was treated with cataract surgery in the follow-up period. Conclusions: In this small case series with long-term follow-up, treatment of non-infectious uveitic macular edema with the injectable fluocinolone acetonide implant was associated with improved central retinal thickness and corrected distance visual acuity and a manageable safety profile. The advantage of this device is the long-term drug release and the fact that it can be injected into the vitreous as a minor surgical procedure, which is in contrast to other treatment options

High order aberration and straylight evaluation after cataract surgery with implantation of an aspheric, aberration correcting monofocal intraocular lens

<b>AIM:</b>To evaluate the quality of vision in respect to high order aberrations and straylight perception after implantation of an aspheric, aberration correcting, monofocal intraocular lens (IOL).<b>METHODS:</b>Twenty-one patients (34 eyes) aged 50 to 83y underwent cataract surgery with implantation of an aspheric, aberration correcting IOL (Tecnis ZCB00, Abbott Medical Optics). Three months after surgery they were examined for uncorrected (UDVA) and corrected distance visual acuity (CDVA), contrast sensitivity (CS) under photopic and mesopic conditions with and without glare source, ocular high order aberrations (HOA, Zywave II) and retinal straylight (C-Quant).<b>RESULTS:</b>Postoperatively, patients achieved a postoperative CDVA of 0.0 logMAR or better in 97.1% of eyes. Mean values of high order abberations were +0.02±0.27 (primary coma components) and -0.04±0.16 (spherical aberration term). Straylight values of the C-Quant were 1.35±0.44 log which is within normal range of age matched phakic patients. The CS measurements under mesopic and photopic conditions in combination with and without glare did not show any statistical significance in the patient group observed (<i>P</i>≥0.28).<b>CONCLUSION:</b>The implantation of an aspherical aberration correcting monofocal IOL after cataract surgery resulted in very low residual higher order aberration (HOA) and normal straylight

Metabolic syndrome negatively impacts early patency of saphenous vein grafts

Background Coronary artery bypass grafting has been performed for a long period utilizing saphenous vein grafts, the fate of which might be crucial to prognosis following the operation. Metabolic syndrome, on the other hand, has become an increasingly important part of cardiovascular practice. We examined whether there was any negative effect of metabolic syndrome on saphenous vein graft patency in a relatively short term (<= 5 years)

In-vitro glistening formation in six different foldable hydrophobic intraocular lenses

Background!#!Glistenings describe small, refractile microvacuoles that may arise within the intraocular lens (IOL) material and reduce the patients' quality of vision. Lenses composed of hydrophobic acrylic material are particularly affected by glistening formation. In this study, we compared the tendency of glistening formation in six different types of hydrophobic acrylic intraocular lenses (IOLs).!##!Methods!#!We used a well-established accelerated laboratory method to develop glistenings in the following IOLs: Vivinex XY1 (Hoya), AcrySof SN60WF (Alcon), Tecnis ZCB00 (AMO), Avansee PN6A (Kowa), Aktis SP NS-60YG (Nidek), and CT Lucia 601P (Zeiss). IOLs were first immersed in saline at 45 °C for 24 h and then at 37 °C for 2.5 h in a water bath. Microvacuole (MV) density and size (Miyata grading) were documented and calculated using an image analysis program.!##!Results!#!The mean glistening density [MV/mm!##!Conclusions!#!While all tested IOLs showed glistenings with the accelerated laboratory method, the Aktis and SN60WF showed the highest microvacuole density, followed by the CT Lucia. In comparison, the Vivinex, Tecnis, and Avansee IOLs showed far fewer number of glistenings

Acute heart failure with accompanying chronic obstructive pulmonary disease Should we focus on beta blockers?

Background. Acute heart failure (AHF) with systolic dysfunction is associated with increased morbidity and mortality, and optimal therapy is not well established, despite the findings of evidence-based medicine. Beta blockers provide a mortality and morbidity benefit in patients with chronic systolic HF, and are currently indicated in all stages of patients with systolic HF. We evaluated therapies before discharge, in particular beta blockers, in patients hospitalized with AHF with and without accompanying chronic obstructive pulmonary disease (COPD)