Early intraocular lens explantations: 10-year database analysis.

BACKGROUND: The aim of this study was to analyze the causes and characteristics of IOL explantation within the first year after primary implantation. METHODS: In this retrospective, cross sectional database study, a database consisting of over 2500 IOL explants sent from 199 national and international doctors over the past 10 years was analyzed. All IOLs explanted within the first year after implantation were included in this analysis. Explants with insufficient information as well as phakic and Add-on IOLs were excluded. Main outcome measures were the reason for explantation, the time between implantation and explantation, as well as IOLs' and patients' characteristics. Additionally, the explanted IOLs were microscopically and histologically analyzed, as required. RESULTS: Of all explanted IOLs from the database, 1.9% (n = 50) were explanted within the first year after implantation. The most frequent reasons for early IOL explantation were IOL dislocation (32%), visual intolerance (26%), opacification (20%), and intraoperative complications (16%). The time between implantation and explantation was the shortest in cases with intraoperative complications (1.5 ± 3.1 days), followed by IOL dislocation (90.9 ± 103.9 days), visual intolerance (98.3 ± 86.5 days), opacifications (253.5 ± 124.0 days) and other indications (249.7 ± 124.0 days). Calcification of hydrophilic IOLs was the main type of opacification (80%). Notably, seven IOLs required immediate intraoperative exchange due to an intraoperative crack in the optic or a torn off haptic. CONCLUSION: Indications for early IOL explantation were IOL dislocation, visual intolerance, opacification, and intraoperative complications. Especially intraoperative damages to the IOL and early calcification show a potential for improvement of affected IOLs and implantation systems.

The Development and Status of Eye Banking with Special Focus on the Commitment of LIONS Clubs. / Entwicklung und Stand des Hornhautbankings unter besonderer Berücksichtigung des Engagements von LIONS Clubs.

BACKGROUND: Ever since the first successful keratoplasty in 1905, there has been a need to store corneas for transplantation. R. Townley Paton founded the first eye bank in New York in 1944. With Helen Keller's call in 1925 for LIONS to "constitute themselves Knights of the Blind in the crusade against darkness", LIONS Clubs International has become involved in the establishment of eye banks worldwide. This paper presents the development of eye banking in general and with special attention to the support offered by LIONS Clubs. METHODS: Selective literature search through PubMed, Google Scholar and Google in close cooperation with the LIONS Eye Banks already established in Germany, LIONS Clubs International (USA) and the Julius Hirschberg Society (Austria). Analysis focused on the founding processes of 6 German eye banks and their current services. RESULTS: Filatov was the first to keep donor eyes in a cool, moist container for a few days. In 1973, Summerlin et al described the technique of organ culture for donor corneas, and McCarey & Kaufman described a liquid storage medium in 1974. LIONS Clubs International and their organisational structure first supported an eye bank in the US in 1952, outside America in Hong Kong in 1962 and in Germany in 1969. Funding is provided across all levels of LIONS as network support and material resources. In general, staff funding is not provided. Of the 88 eye banks operating worldwide today, 44 are called LIONS Eye Banks. 6 of the current 26 eye banks in Germany are operating under LIONS sponsorship and run by departments of ophthalmology at university medical centres. Although the number of transplants has increased in recent years due to new surgical techniques, the number of patients waiting for donor tissue is also growing as a result of the broadening indication. CONCLUSIONS: Even today, the availability of donor corneas limits patient care. Eye banks help to meet the need for donor corneas. However, the techniques and technical equipment of eye banks must undergo continuous improvement. The local, national and international network of LIONS Clubs can assist in establishing these in order to facilitate legal requirements and structural developments. This support frequently lasts for many years, often triggers additional public commitment and is thus also a supporting element for the future development of eye banking in Germany.

[In Vitro Evaluation of the Optical Quality of Segmental Refractive Multifocal Intraocular Lenses]. / In-vitro-Untersuchung zur optischen Qualität segmental refraktiver multifokaler Intraokularlinsen.

OBJECTIVES: In customised patient care, it is important to know the optical quality of different intraocular lenses (IOL). In this study, the optical quality of three segmental intraocular lenses were compared. MATERIALS AND METHODS: The LENTIS Comfort LS-313 MF15, LENTIS Mplus X LS-313 MF30 and LENTIS High Add IOL LS-313 MF80 (Oculentis, Berlin, Germany) with a far power of + 21 D were analysed at the optical bench OptiSpheric IOL PRO (Trioptics GmbH, Wedel, Germany). The lenses have almost the same optical design but differ in the power of the near segment. The MF15 has a + 1.5 D addition to improve vision in intermediate distances, the MF30 has a near addition of + 3 D and the MF80 has a near addition of + 8 D. The modulation transfer function area (MTFa) and the Strehl ratio were examined for apertures of 3 mm (photopic) and 4.5 mm (mesopic). RESULTS: The MTFa values for the far focus are 33.34/30.80/51.53 (MF15/MF30/MF80) with an aperture of 3 mm and 25.38/22.52/43.15 for 4.5 mm. The MTFa values for the intermediate focus are 29.85/16.21/6.25 for a 3 mm aperture and 23.92/8.05/3.08 for 4.5 mm. The MTFa values for the near focus are 9.75/21.49/33.12 for an aperture of 3 mm and 4.95/22.70/31.68 for 4.5 mm. The Strehl ratio of the far focus is 0.34/0.30/0.52 for an aperture of 3 mm and 0.24/0.22/0.43 for 4.5 mm. For the intermediate focus, the Strehl ratio is 0.30/0.17/0.07 for an aperture of 3 mm and 0.24/0.08/0.03 for 4.5 mm. The Strehl ratio of the near focus is 0.10/0.22/0.33 for an aperture of 3 mm and 0.05/0.23/0.32 for 4.5 mm. CONCLUSION: We confirmed that the addition influences the optical quality of segmental bifocal intraocular lenses. For the far focus, the results of the MF15 and MF30 are similar. In intermediate distances, the MF15 achieves the best results. For near distances, the MF30 achieves better optical values than the MF15. The lens MF80, which has been designed for patients with maculopathies, achieves good results for far and near distances.

[Comparison of Long-term Results with Small Incision Refractive Lenticule Extraction (ReLEX SMILE) vs. Femto-LASIK]. / Vergleich der Langzeitergebnisse bei Small Incision Refractive Lenticule Extraction (ReLEx SMILE) und Femto-LASIK.

AIM: Our aim was to retrospectively compare ReLEx Smile to femtosecondlaser-assisted LASIK (FsLASIK, femto-LASIK) in terms of safety, efficacy, stability as well as intraoperative complications. Comparable studies only show the results over the course of 3 years, making our data the first to examine longer term results. MATERIALS/METHODS: To accomplish this, we compared 404 eyes after FsLASIK (Mel 80, Carl Zeiss Meditec) and 1192 eyes after ReLEx SMILE (VisuMax, Carl Zeiss Meditec). We collected patients' data at 6 months, 1 year, 2 years and 5 years after refractive surgery. RESULTS: Five years postoperatively, the 2 methods showed equally good results in all investigated parameters. Over the course of these 5 years, the ReLEx SMILE achieved significantly better results for safety (p < 0.05) after 6 months, 1 year and 2 years. The results for visual acuity were significantly better for ReLEx SMILE after 1, 2 and 3 years. The predictability of both methods was consistently good over the entire period of time and intraoperative complications were equally low. CONCLUSION: After retrospective analysis of the visual outcomes of our patients up to 5 years after surgery, the ReLEx SMILE method turned out to be at least as safe and efficient as the FsLASIK. The stability of the refractive outcome was equally good with the 2 methods. Due to the high level of satisfaction experienced by the patients, high patient comfort intra- and postoperatively, absence of dry eyes, and the absence of flap complications, ReLEx SMILE has replaced the FsLASIK in our daily practice and become our method of choice for corneal refractive surgery when it comes to the correction of myopia and myopic astigmatism.

[Impact of Near Addition on the Optical Quality of Diffractive Multifocal Intraocular Lenses - a Laboratory Study Using an Optical Bench]. / Auswirkungen der Nahaddition auf die optische Qualität von diffraktiven multifokalen Intraokularlinsen ­ eine Laborstudie an der optischen Bank.

Purpose To analyse the optical quality of diffractive multifocal intraocular lenses (IOLs) with different near additions in a laboratory study. Methods We analysed the AcrySof® IQ ReSTOR® + 2.5 D SV25T0 (Alcon Laboratories inc., Fort Worth, USA), the AcrySof® IQ ReSTOR® + 3.0 D SN6AD1 (Alcon, USA) and the TECNIS® ZMA00 and ZMB00 (Abbott Medical Optics, USA) with a power of 21D for the distance, using the OptiSpheric® IOL PRO optical bench (TRIOPTICS, Wedel, Germany). The lenses have a similar optical design but different near additions: The ReSTOR + 2.5 D has a near addition of + 2.5 D, the ReSTOR + 3.0 D has a near addition of + 3.0 D and both TECNIS IOLs have a near addition of + 4.0 D. We evaluated the modulation transfer function area (MTFA) and the Strehl ratio. Additionally the optical qualities of the IOL were compared using USAF (United States Air Force)-Target pictures. Results The MTFA at the far focus (ReSTOR + 2.5 D/ReSTOR + 3.0 D/TECNIS) was 47.85/42.06/33.57. The MTFA was 11.05/9.54/8.60 for intermediate distances. MTFA at the near focus was 20.11/29.50/33.39. The Strehl ratio was 0.48/0.42/0.29 at the far focus, 0.11/0.10/0.09 at the intermediate focus and 0.20/0.30/0.34 at the near focus. The USAF Target pictures correlated with these measurements. Conclusion At the near focus, the TECNIS ZMA00 and ZMB00 performed the best, while the ReSTOR + 2.5 D performed the worst. At the intermediate distance, all IOLs achieved similar results. At the far focus, the ReSTOR + 2.5 D performed the best. Surgeons can choose the right IOL for the patients' individual needs, because a broad range of near additions in diffractive multifocal IOLs is available these days.

Distribution of pseudoexfoliation material on anterior segment structures in human autopsy eyes after cataract surgery with intraocular lens implantation.

The purpose of the study was to evaluate the distribution and amount of pseudoexfoliation material (PXM) on anterior segment structures in pseudophakic human autopsy eyes with pseudoexfoliation (PEX) syndrome and to study its impact on fixation and decentration of posterior chamber intraocular lenses (IOLs). Sixteen human autopsy eyes (donor age [mean ± SD] 77.5 ± 8.6 years; range, 70-90 years) with history of cataract surgery and PEX syndrome were analyzed for distribution and accumulation of PXM on structures of the anterior segment by light microscopy. Quantitative IOL decentration measurements were performed using the Miyake-Apple posterior view technique. All 16 eyes displayed IOLs which were either fixed symmetrically in the capsular bag (n = 8) or asymmetrically with one haptic in the sulcus and one in the bag (n = 7) or at the pars plicata of the ciliary body (n = 1). In the majority, PXM was found around the pars plicata (average grade: 1.6 ± 0.53 µm) and the lens capsule (average grade: 1.05 ± 0.46 µm). Minor amounts were detected at the pars plana and the trabecular meshwork. IOL decentration measurements ranged from 0.51 ± 0.35 (symmetrical-fixation) to 0.61 ± 0.43 mm (asymmetrical-fixation). There was only a weak statistically not significant correlation in regard to the amount of PXM and IOL decentration and between PXM distribution and the IOL fixation site. PXM contributes to weakening of the suspensory apparatus of the crystalline lens. Although PXM induced tissue alterations predispose for a broad spectrum of intra- and postoperative complications, the amount and distribution of PXM on different anterior segment structures showed only a weak correlation to IOL decentration or fixation location.

Evaluation of Parameters and Nozzle Tip Damage after Clinical Use of Three Hydrophilic Intraocular Lens Injector Models.

Purpose: To assess the nozzle tip damage and the parameters of three different hydrophilic intraocular lens (IOL) injector models. Methods: After routine cataract surgeries at the University Eye Hospital Heidelberg, all the used IOL injectors were collected from the operating room and sent to our laboratory. Nozzle tip damage was assessed under a microscope and graded as follows: no damage (grade 0), slight scratches (1), deep scratches (2), extensions (3), cracks (4), and bursts (5). Each damage grade was assigned a score from 0 to 5, and the total damage score for each injector system was calculated and compared. Nozzle tip parameters (diameters and areas), plunger tip parameters, and tip angles were also measured in each model. Results: The damage scores were (median, Q3-Q1): 1 (1-1) for Accuject, 1 (1-1) for Bluemixs, and 1 (1-1) for RayOne. There was no statistically significant difference in the damage scores between the study groups (P > 0.05). The outer cross-sectional vertical and horizontal diameters were 1.69 and 1.69 mm for Accuject, 1.69 and 1.69 mm for Bluemixs, and 1.70 and 1.71 mm for RayOne. Plunger tip areas were 0.78 mm2 for Accjuect, 0.74 mm2 for Bluemixs, and 0.43 mm2 for RayOne. Plunger tip area/inner cross-sectional area of the nozzle tip (%) was 31.2% for RayOne, 66.7% for Accuject, and 63.8% for Bluemixs. The tip angles for three injector models were 56° (Accuject), 56° (Bluemixs), and 44° (RayOne). Conclusions: All the injector models showed mild to moderate damage to the nozzle tip after IOL implantation, even with smaller diameter tips. RayOne resulted in the lowest ratio between plunger tip area and inner cross-sectional area of the nozzle tip and a better distribution of damage categories than the other two groups. All three injector models had relatively small tip parameters. If smaller incisions are required in certain patients, smaller tip parameters should be considered.

Forward Light Scattering of the Vitreous Gel After Enzymatic Aging: An In Vitro Model to Study Vitreous Opacification.

Purpose: Symptomatic vitreous opacifications, so-called floaters, are difficult to objectively assess majorly limiting the possibility of in vitro studies. Forward light scattering was found previously to be increased in eyes with symptomatic floaters. Using an objective setup to measure forward light scattering, we studied the effects of enzymatically digesting the components of the vitreous body on straylight to develop an in vitro model of vitreous opacifications. Methods: Fifty-seven porcine vitreous bodies were digested using hyaluronidase, collagenase, trypsin, and bromelain, as well as using a combination of hyaluronidase + collagenase and hyaluronidase + bromelain. A modified C-Quant setup was used to objectively assess forward light scattering. Results: Depletion of hyaluronic acid majorly increased vitreous straylight (mean increase 34.4 deg2/sr; P = 0.01), whereas primarily digesting the vitreous gel with collagenase or trypsin did not significantly affect straylight. When collagenase or bromelain is applied in hyaluronic acid depleted vitreous gels, the increase in forward light scattering is reversed partially. Conclusions: The age-related loss of hyaluronic acid primarily drives the increase in vitreous gel straylight induced by conglomerates of collagen. This process can be reversed partially by digesting collagen. This in vitro model allows the objective quantification and statistical comparison of straylight burden caused by vitreous opacities and, thus, can serve as a first testing ground for pharmacological therapies, as demonstrated with bromelain.

Viscoelastic, Optical, and Surgical Properties of Vitreous Body Replacement Hydrogels After Aging Compared to Porcine Vitreous Bodies And Silicone Oils.

Purpose: First- (monomers), second- (pre-gelated), and third- (in situ gelating after injection) generation hydrogels were previously introduced to replace the vitreous body after vitrectomy surgery. In this study, we evaluated the surgical, optical, and viscoelastic properties of vitreous body replacement hydrogels before and after an accelerated aging protocol previously applied to intraocular implants. Methods: Measurements of injection force, removal speed using a clinically established vitrectomy setup, as well as evaluation of forward light scattering and viscoelastic properties before and after an accelerated aging protocol were conducted. Results were compared to porcine and human vitreous bodies, as well as currently clinically applied lighter- and heavier-than-water silicone oils. Results: Removal speed of all tested hydrogels is substantially lower than the removal speed of porcine vitreous body (0.2 g/min vs. 2.7 g/min for the best performing hydrogel and porcine vitreous body, respectively). Forward light scattering in second-generation vitreous body replacement hydrogels was higher after the aging process than the straylight of the average 70-year-old vitreous body (9.4 vs. 5.5 deg2/sr, respectively). The viscoelastic properties of all hydrogels did not change in a clinically meaningful manner; however, trends toward greater stiffness and greater elasticity after aging were apparent. Conclusions: This study demonstrates surgical weaknesses of the hydrogels that need to be addressed before clinical use, especially low removal speed. Pre-linked hydrogels (second-generation) showed inferior performance regarding surgical properties compared to in situ gelating hydrogels (third-generation). Translational Relevance: This study highlights possible pitfalls regarding surgical and optical properties when applying vitreous replacement hydrogels clinically.

Functional and Morphological Responses to Fluocinolone Acetonide 0.19 mg in Noninfectious Uveitic Macular Edema Evaluated as the Area-Under-the-Curve.

Purpose: This study investigated the impact of baseline clinical and optical coherence tomography (OCT) factors on the response to a 0.19-mg fluocinolone acetonide (FAc) implant in patients with noninfectious uveitic macular edema evaluated by the area under the curve over 24 months. Methods: A retrospective study was conducted of eyes of patients with noninfectious uveitic macular edema undergoing FAc treatment, with follow-up from baseline to 24 months. The area under the curve (AUC) of best-corrected visual acuity (BCVA) and the central macular thickness (CMT) were calculated using the trapezoidal rule. Clinical and OCT data at the time of FAc administration were collected, and associations with AUC of BCVA and CMT changes were investigated. Results: Twenty-three patients were enrolled. BCVA and CMT significantly improved after FAc implantation (P < 0.05). AUCBCVA and AUCCMT were 0.41 ± 0.33 logarithm of minimal angle of resolution/6 months and 320.15 ± 321.64 µm/6 months, respectively. Better baseline BCVA (coefficient [coef.] = 0.83, P < 0.001) and macular thickness reduction after FAc administration (coef. = -0.0001, P < 0.05) were associated with better BCVA after FAc treatment. In contrast, baseline OCT biomarkers such as ellipsoid zone reflectivity and choroidal vascularity index, sex, or disease duration before FAc injection showed no correlation with AUCBCVA and AUCCMT (P > 0.05). The younger the patient at the time of FAc injection, the greater the reduction in CMT (coef. = 1.76, P < 0.05). Conclusions: Among all clinical and morphological baseline factors, Baseline BCVA was the strongest predictor for AUCBCVA, while no association with baseline OCT features was observed. Overall, improvement of BCVA and CMT after FAc injection was maintained over 24 months. This study is registered in the German Clinical Trials Register under the DRKS-ID: DRKS00024399.

Comparison of a Presbyopia-Correcting Supplementary Intraocular Lens Combination and a Capsular-Bag Lens: An In Vitro Study.

We evaluated the optical quality of two approaches to trifocality: polypseudophakia versus monopseudophakia. The combination (polypseudophakia) of a monofocal Basis Z B1AWY0 and AddOn Trifocal A4DW0M intraocular lens (IOL) was compared to using one Basis Z Trifocal B1EWYN IOL, all from 1stQ GmbH. In both approaches, we measured modulation transfer function (MTF) and Strehl Ratio (SR) values at 3.0 and 4.5 mm pupil sizes. We determined the through-focus (TF) MTF at 25, 50 and 100 lp/mm for the 3 mm aperture. United States Air Force (USAF) target images were recorded. MTF measurement of the trifocal lens and the combined monofocal and trifocal AddOn IOL showed good performance at the far and near focus for the 3 mm aperture. For the 4.5 mm aperture the MTF improved for the far focus but decreased for the intermediate and near focus. TF MTF showed better contrast at the far focus for the polypseudophakic setup but at the expense of the efficiency at the near focus. However, the USAF chart images revealed only minimal differences between both approaches. The optical quality of the polypseudophakic approach was not affected by the presence of two IOLs instead of one and proved to be comparable with the performance of one capsular-bag-fixated trifocal IOL. Differences between the single vs. two-lens approach seen in the TF MTF analysis could be attributed to the optical design that varied between the trifocal models.

Late central graft detachment due to double endothelial layer after repeat Descemet membrane endothelial keratoplasty.

Purpose: To report late central graft detachment after repeat Descemet membrane endothelial keratoplasty (DMEK) without visual reduction. Observations: A 71-year-old patient with Fuchs' endothelial corneal dystrophy received a DMEK in his left eye. At 11 month post-operatively, a subtotal graft detachment was noted. Due to increasing corneal edema with vision loss, the first DMEK was removed and a repeat-DMEK was performed. At four months post repeat-DMEK, the graft was fully adherent to the posterior stroma. There was no significant corneal edema, and the best corrected visual acuity was 20/25. At 16-months after repeat-DMEK, a central graft detachment was noted, but there was no concurrent corneal edema or any loss of visual acuity. The mean density of the central endothelial cells was measured at 842 cells/mm2. Given the lack of corneal edema, visual reduction or subjective visual complaint, the graft detachment was followed-up for up to 20-months post repeat-DMEK with no further intervention, where the central cornea remained clear. Conclusions and Importance: To our knowledge, this is the first report of a central repeat-DMEK graft detachment that occurred 16 months after surgery despite initial attachment. Interestingly, there was no concurrent corneal edema or vision reduction. We describe a potential mechanism for clear central cornea in the presence of a central graft detachment after repeat-DMEK.

Impact of Lens Opacity on Optical Coherence Tomography Angiography Metrics.

PURPOSE: To evaluate the impact of lens opacity on the reliability of optical coherence tomography angiography metrics and to find a vessel caliber threshold that is reproducible in cataract patients. METHODS: A prospective cohort study of 31 patients, examining one eye per patient, by applying 3 × 3 mm macular optical coherence tomography angiography before (18.94 ± 12.22 days) and 3 months (111 ± 23.45 days) after uncomplicated cataract surgery. We extracted superficial (SVC) and deep vascular plexuses (DVC) for further analysis and evaluated changes in image contrast, vessel metrics (perfusion density, flow deficit and vessel-diameter index) and foveal avascular area (FAZ). RESULTS: After surgery, the blood flow signal in smaller capillaries was enhanced as image contrast improved. Signal strength correlated to average lens density defined by objective measurement in Scheimpflug images (Pearson's r: -.40, p: .027) and to flow deficit (r= -.70, p < .001). Perfusion density correlated to the signal strength index (r = .70, p < .001). Vessel metrics and FAZ area, except for FAZ area in DVC, were significantly different after cataract surgery, but the mean change was approximately 3-6%. A stepwise approach in extracting vessels according to their pixel caliber showed a threshold of > 6 pixels caliber (∼20-30 µm) was comparable before and after lens removal. CONCLUSION: In patients with cataract, OCTA vessel metrics should be interpreted with caution. In addition to signal strength, contrast and pixel properties can serve as supplementary quality metrics to improve the interpretation of OCTA metrics. Vessels with ∼20-30 µm in caliber seem to be reproducible.

[Hydrophobic surface properties of hydrophilic acrylic lenses do not protect against calcification]. / Hydrophobe Oberflächeneigenschaften hydrophiler Acryllinsen schützen nicht vor Kalzifikation.

BACKGROUND: Opacification through calcification of hydrophilic acrylic intraocular lenses is a serious complication of cataract surgery, which usually results in explantation of the lens. In the process of calcification, the intraocular lens material plays a crucial role: calcification only occurs in hydrophilic acrylic lenses. Hydrophobic acrylic lenses show no crystal formation within the polymer. Hydrophilic acrylic lenses from some manufacturers have hydrophobic surface properties. The question arises as to what influence these surface properties have on the risk of calcification. OBJECTIVE: The present study investigated whether the hydrophobic surface properties of hydrophilic acrylic lenses can prevent calcification. MATERIAL AND METHODS: Using an electrophoretic in vitro model of calcification, two hydrophilic lenses with hydrophobic surface properties were compared to two hydrophilic lenses and a hydrophobic negative control to determine the risk of calcification. The lenses were then analyzed by optical microscopy, Alizarin Red and Von Kossa staining, scanning electron microscopy (SEM) and energy dispersive X­ray spectroscopy (EDX). RESULTS: All four hydrophilic lens models showed calcification within the polymer. No difference was found between the hydrophilic lenses and the hydrophilic lenses with hydrophobic surface properties in terms of crystal formation. The hydrophobic negative control showed no calcification. CONCLUSION: The investigation conducted in this study under standardized conditions could show that hydrophobic surface properties of hydrophilic acrylic lenses do not protect against calcium phosphate crystal formation within the polymer. There also is a risk of calcification in these lens models.