Proportion and risk factors of epiretinal membrane in residents of Brussels with versus without diabetes mellitus.

PURPOSE: To compare the proportion of epiretinal membrane (ERM) between individuals with diabetes mellitus (DM) and without DM, who live in Brussels, to investigate possible risk factors for ERM formation and to compare the results with the ones of large population studies. METHODS: Participants were divided into two groups; 99 patients with DM (group A) and 103 individuals without DM (group B). All participants underwent an undilated 7-field color fundus photography and a spectral domain optical coherence tomography (SD-OCT). Age, gender, race, type of diabetes, duration of medical treatment of diabetes, HbA1C rate, smoking, previous cataract surgery and educational level were investigated as possible risk factors. RESULTS: Epiretinal membrane was detected in 17.2% of group A and in 11.7% of group B participants. The difference is not statistically significant (χ2 (1) = 1.252, p = 0.263). The proportion of ERM was significantly associated with age in both groups (p = .009 and p < .001 respectively), as well as with smoking (p = .023) and previous cataract surgery (p = .028) in patients with DM. CONCLUSION: There is no statistically significant difference of ERM proportion between the two groups of the study. Age was recognized as a risk factor for both groups, while smoking and previous cataract surgery were identified as predictors only for diabetics.

Current Developments in the Management of Amblyopia with the Use of Perceptual Learning Techniques.

Background and Objectives: Amblyopia is a neurodevelopmental disorder caused by interocular suppression of visual input, affecting visual acuity, stereopsis, contrast sensitivity, and other visual functions. Conventional treatment comprises occlusion of the sound eye. In recent years, novel therapies that deploy perceptual learning (PL) principles have been introduced. The purpose of this study is to assess the latest scientific data on this topic. Materials and Methods: For this purpose, we conducted a literature search for relevant studies published during the previous 4 years (2020-2023). Results: A plethora of visual perceptual learning protocols have been recently developed. Dichoptic video games, contrast rebalanced movies, and online perceptual training platforms are the main formats. Perceptual learning activates neuroplasticity, overcomes interocular suppression, and improves the visual impairments induced by amblyopia. Conclusions: This novel treatment is effective in both children and adults, as well as in patients non-responding to patching.

Clinical variations and therapeutic challenges in the management of symptomatic retinal artery macroaneurysm: a tertiary center experience.

PURPOSE: To find out clinical characteristics, therapeutic options, and visual outcome in symptomatic retinal artery macroaneurysm (RAMA) patients. METHOD: Newly diagnosed cases of symptomatic RAMA from January 2015 to December 2019 were included. Fifteen eyes of 15 patients with mean age 62.46 years ± 14.89 (SD) fulfilled the inclusion criteria. RESULT: Hypertension was present in 66.6% of the patients, and the commonest site was superotemporal (12 eyes, 80%). The most commonly employed treatment was Nd: Yag laser hyaloidotomy in 4 eyes (26.6%). Other treatments were intravitreal bevacizumab in 3 eyes (20%), focal laser with intravitreal bevacizumab in 3 eyes (20%), PPV with focal laser (13.3%) in 2, focal laser only in one (6.6%), PPV with focal and intravitreal bevacizumab in one (6.6%). The mean best-corrected visual acuity (BCVA) at baseline was 1.35 ± 0.84 LogMAR, which improved to 0.39 ± 0.53 LogMAR at the last follow-up. Presenting VA 0.77 (±0.40) improved to 0.20 (±0.17) p value (0.180) in intravitreal bevacizumab only group, 1.29 (±0.35) to 0.75 (±0.15) p value 0.66 in Nd: Yag laser group, 2.67 (±0.58) to 0.46 (±0.28) p value 0.019 in PPV group and did not improve in combined anti-VEGF and focal laser group due to dense hard exudates at the fovea in one and persistent cystoid macular edema in another case. CONCLUSION: With regard to its presentation, which can vary tremendously, there are no approved guidelines for its treatment. The present study reinforces the need for a treatment guideline development. Customization of treatment should be considered depending on the clinical presentation of each case.

Outcomes of toric IOL implantation guided by iris-registered femtosecond laser capsulotomy markings.

PURPOSE: To assess the accuracy and stability of iris-registered femtosecond laser-assisted anterior capsule axis markings (compensating cyclotorsion) along with refractive and visual outcomes after toric IOL implantation. METHODS: This prospective case series included eyes with visually significant cataracts and regular corneal astigmatism ranging from 1.25D to 4.0D, which received FLACS and toric IOL implantation, at The Eye Institute of West Florida, Largo, Florida, USA. Preoperative iris registration was used in conjunction with a femtosecond laser platform to create cyclotorsion corrected axis marks at the capsulotomy edge to facilitate toric IOL axial alignment. Patients were examined one, seven and thirty days after surgery to assess capsulotomy marks axis, toric IOL axis along with visual and refractive outcomes. RESULTS: Eighteen eyes of 13 patients aged 74.35 ± 8.65 years were included. Mean pre-op CDVA was 0.24 ± 0.16 LogMAR, while mean post-op UDVA was 0.09 ± 0.09 LogMAR. Mean pre-op corneal astigmatism was 1.85 ± 0.41 D, decreasing to 0.24 ± 0.41 D of refractive astigmatism postoperatively (p < 0.001). The capsular toric axis markings were visible in 100% of eyes throughout the follow-up; the mean difference between intended capsulotomy mark axis and measured capsulotomy mark axis was 1.6°, 1.7° and 1.3 o at the 1, 7 and 30 day intervals (p > 0.05), respectively. No capsule-related or any other type of complications was noted. CONCLUSIONS: Iris-registered femtosecond laser-assisted anterior capsule axis markings are safe and may be considered as an alternative option to the known axis marking techniques for toric IOL axial alignment at the time of cataract surgery.

Ease of Hydrodissection during Phacoemulsification: A Comparison between Patients with and Those without Exfoliation Syndrome.

BACKGROUND: Exfoliation syndrome (XFS), which is associated with increased surgical complications during phacoemulsification, has a relatively high incidence in Greece. Multiannual surgical experience in XFS patients has led to the clinical observation that hydrodissection occurs more easily in XFS patients. OBJECTIVE: To compare the ease of hydrodissection between cataract patients with and those without XFS. METHODS: One hundred and fifteen patients with senile cataract were included in the study. Forty-two of them had XFS. All patients underwent uneventful phacoemulsification by the same surgeon. For hydrodissection, three 1-mL insulin syringes were filled with 0.5 mL balanced salt solution (BSS). Sequentially, each one was quickly and continuously injected underneath the 3, 6, and 9 o'clock positions of the anterior lens capsule. If lens mobilization was achieved with this procedure, hydrodissection was characterized as "easy." RESULTS: The two groups were matched for age, gender, the biomicroscopic type of cataract, and the presence of diabetes mellitus. Glaucoma occurred more often among the XFS patients (p = 0.002). In 39 of the 42 exfoliation patients (92.8%), "easy" hydrodissection was recorded. In the control group, the corresponding number was 47 out of 73 (64.3%). The two groups differed significantly (p = 0.001). CONCLUSIONS: Hydrodissection was more easily performed on the XFS patients than on the controls. This finding could be related to the extensive ultrastructural subepithelial alterations of the anterior lens capsule in XFS, as recently described in electron microscopy studies. We suggest that less BSS can be used for hydrodissection in XFS patients during phacoemulsification.

Severe Abnormalities of Lens Epithelial Cells in Exfoliation Syndrome: A Transmission Electron Microscopy Study of Patients with Age-Related Cataract.

Background and objectives: The aim of this study was to examine via electron microscopy the lens epithelial cells in age-related cataracts and compare the findings between patients with and without exfoliation syndrome, in the Greek population. Materials and Methods: Twenty-one patients with age-related cataracts, older than 60 years, were included in the study. Eleven of them also suffered from exfoliation syndrome. Anterior lens capsules, obtained during phacoemulsification, were examined with a transmission electron microscope. Results: In all cases, ultrastructural features of diffuse intracellular and extracellular oedema were noticed to a varying degree and transparent vacuoles were detected. Often, there was more than one layer of cells, giving the impression that healthier cells tried to cover neighboring cells presenting extensive damage. Commonly, cells lost their regular shape and appeared with expanded nuclei carrying dense granules. Apoptotic cells were also detected. The epithelial cells frequently were completely destroyed or absent, exhibiting loose connections amongst them or with the basement membrane. In exfoliation syndrome (XFS) patients the alterations were more severe. Additionally, the lens epithelial cells (LECs) apical cell membrane appeared with varying distances from the basement membrane, due to different cell "heights", creating an irregular margin of the epithelium (p<0.05). Conclusion: Transmission electron microscope (TEM) examination revealed ultrastructural abnormalities in all patients' lens epithelia, more extended and more frequently observed in XFS group. In all cases, the lesions were comparable to those described in severe pathologies, all of which were excluded from the study. Environmental factors such as increased ultraviolet B (UVB) radiation exposure in Mediterranean countries, genetic factors, epigenetic factors, or all of them, could contribute to these alterations. Further epidemiological and molecular biology research is needed, so as to justify these results.

Transmission electron microscopy study of undescribed material at the anterior lens capsule in exfoliation syndrome.

PURPOSE: In the present study, we aimed to examine the anterior lens capsule using transmission electron microscopy (TEM) and compare the findings in patients with and without exfoliation syndrome (XFS). METHODS: Eighteen patients with senile cataract, including 10 with XFS, were included. Anterior capsule specimens were obtained from patients during phacoemulsification through continuous curvilinear capsulorrhexis, and were examined via TEM. RESULTS: In the XFS group, in addition to the typical fibrillar material above the basement membrane of the lens capsule, another unknown, microgranular, electron-dense, unbound material was observed beneath the lens epithelium. Larger formations appeared to detach from the surface of the epithelial cells, and oval or crescent-shaped structures of an electron-denser material were less commonly observed on the apical side of the epithelium. Membranous structures were occasionally attached to epithelial cells that often exhibited thicker or ruptured cell membranes on their apical-free side, along with deposits of electron-dense material. Degenerative lesions of various severities were observed at the epithelium in both groups. CONCLUSION: The anterior lens capsule epithelium in patients with XFS exhibits a highly irregular and rough margin on its free side, with unbound material over its membrane, which probably contributes to loose contact with the underlying lens and leads to different clinical behaviors in XFS eyes during cataract surgery.

Outcomes of switching treatment to aflibercept in patients with macular oedema secondary to central retinal vein occlusion refractory to ranibizumab.

PURPOSE: To assess the treatment outcome of switching from ranibizumab to aflibercept intravitreal injections in patients with macular oedema secondary to central retinal vein occlusion (CRVO). METHODS: A prospective interventional study was conducted in a tertiary retina service in Leicester Royal Infirmary, UK, where patients with CRVO and associated macular oedema were recruited. First-line treatment involved three monthly ranibizumab injections. Non-responders were defined as patients who despite a minimum of three consecutive injections had persistent intraretinal fluid one month after the last injection. In these cases, a treatment change to aflibercept injections on a per-needed basis was decided. Best-corrected visual acuity (BCVA) and central retinal thickness (CRT) were measured before and after switching of treatment. Follow-up period lasted for a minimum of 24 weeks after switching. RESULTS: Twenty-nine eyes of 29 patients with refractory macular oedema secondary to CRVO were included. All eyes had an average of 4.5 ranibizumab intravitreal injections in a mean period of 6 months without reduction in intraretinal fluid and/or no visual acuity gain. A significant decrease in mean CRT from 633.67 ± 242.42 to 234.62 ± 78.28 µm and improvement in mean BCVA from 1.34 ± 0.66 log MAR to 0.91 ± 0.73 log MAR were noticed after switching treatment to aflibercept. The average number of aflibercept injections needed for oedema resolution was 2.19. CONCLUSIONS: Aflibercept is an effective alternative treatment for macular oedema secondary to CRVO refractory to ranibizumab. Good anatomical and functional result can be achieved with few injections. The maintenance of these results after 6 months is yet to be investigated.

24-month clinical outcomes of a treat-and-extend regimen with ranibizumab for wet age-related macular degeneration in a real life setting.

BACKGROUND: To evaluate the clinical effectiveness and analyze the outcomes of a treat-and-extend (T&E) treatment regimen with ranibizumab for wet age-related macular degeneration (ARMD) in real life clinical settings over the first 2 years (24 months) of treatment. METHODS: Retrospective analysis of visual acuity, spectral domain optical coherence tomography (SD-OCT) parameters and treatment burden data of 56 eyes of 54 unselected treatment naive patients diagnosed with exudative ARMD. Monthly injections were offered until no signs of disease activity such as intra-retinal (IRF) or sub-retinal fluid (SRF) were evident on SD-OCT, followed by a gradual extension of the treatment interval by 2 weeks until a maximum of 12 weeks. RESULTS: The study met its main objective, demonstrating a mean best-corrected visual acuity gain of 8.3 letters (mean 68.8 ± 11) at month 12 and 5.2 letters (mean 65.7 ± 12.3) at 24 months compared to baseline (mean 60.5 ± 8.9). Anatomical improvement was also documented with a mean reduction of central retinal thickness by 139.7 µm at 24 months (244.9 ± 48.3) compared to baseline (384.6 ± 154.9). Forty-seven eyes (83.9% N = 56) gained vision or preserved baseline vision with 23 eyes (41.1%) gaining 10 letters or more at month 12. Out of the 46 eyes that completed 24 months of treatment and monitoring, 27 (58.7% N = 46) kept a BCVA above baseline with 18 of those (39% N = 46) maintaining a 10-letter gain throughout the 24 months. Six eyes (13% N = 46) lost more than 10 letters by month 24. The mean number of injections was 12.1 ± 2.8 over the 24-month period. Twenty-seven eyes (55.1% N = 56) achieved a treatment interval of 10 weeks or more at month 12, while the respective number at month 24 was 20 eyes (43.4% N = 46) in addition though to four more patients (8.7% N = 46) who were not receiving injections at month 24 since they were placed on a Monitor & Extend regime. CONCLUSIONS: This is the first UK real-life study of a T&E treatment protocol with ranibizumab for exudative ARMD in a 24-month period and suggests that such a regimen is clinically effective and can achieve favourable outcomes with a significant reduction of the treatment burden compared to monthly PRN.

Incremental and decremental L- and M-cone driven ERG responses: II. Sawtooth stimulation.

L- and M-cone driven on- and off- ERG responses and their interactions were examined using full field stimuli with sawtooth temporal profiles. The effects of temporal frequency and contrast were studied. ERG recordings were obtained from 21 trichromatic, 1 protanopic, and 1 deuteranopic subjects. ERGs to L-cone increments and decrements resembled those to M-cone decrements and increments, respectively (i.e., of the opposite polarity). Temporal frequency and contrast had little effect on the implicit times. All response components varied linearly with contrast. When stimulated simultaneously, the responsivities of most components were larger for counterphase than for inphase modulation. The retinal processing leading to an ERG response is reversed for L- and M-cone driven responses.

Measurements of elastic modulus for human anterior lens capsule with atomic force microscopy: the effect of loading force.

The purpose of the study was to appraise the effect of loading force magnitude on the determination of the elastic modulus of the anterior lens capsule through atomic force microscopy. Four human anterior lens capsules taken during phacoemulsification cataract surgery were studied, free of epithelial cells, with atomic force microscopy. For the experiment, five different indentation loading forces were applied to near areas of the specimen. Experimental data was exported and analyzed according to the Hertz model to obtain the Young's modulus with regards to the elastic behavior of the material. Force-distance curves were acquired by applying a load of 2, 5, 10, 20 and 30 nN. When examining the results it was evident that determination of Young's modulus of the anterior lens capsule is dependent on the loading force concerning the examined range. Loading forces of 10 and 20 nN led to results without significant difference (p > 0.05) and more reproducible (coefficients of variation 12.4 and 11.7 %, respectively).

ZEPTO-assisted pseudophakic capsulotomy: Precision pulse technology for management of capsular contraction syndrome.

We describe a novel technique that uses precision pulse capsulotomy (PPC) to perform a secondary capsulotomy for the management of anterior capsule contraction syndrome (ACCS), a condition that comprises a late complication after cataract surgery and intraocular lens (IOL) implantation. Micropulse secondary capsulotomy offers a controlled and safe approach for patients with severe anterior capsule contraction syndrome and may be considered as an alternative surgical technique.

Cataract surgery using two 3D visualization systems: Complication rates, surgical duration & comparison with traditional microscopes.

PURPOSE: To compare the complication rates and surgical duration of cataract surgery using two 3D visualization systems and a traditional binocular microscope among experienced and inexperienced surgeons. METHODS: This retrospective case series included 571 eyes that received cataract surgery using either heads up cataract surgery, via a 3D head mounted system (N = 148-Group 1) or a 3D display screen (N = 338 eyes-Group 2), or traditional binocular microscope (N = 85 eyes-Group 3). The surgical records of consecutive patients who underwent cataract surgery by two groups of surgeons (experienced and inexperienced) were reviewed. Patients in all groups received either femtosecond laser assisted cataract surgery (FLACS) or traditional phacoemulsification. Complication rate, as well as duration of cataract surgery were evaluated between all three visualization approaches, between experienced and inexperienced surgeons. RESULTS: There was no statistically significant difference in duration of surgery between all 3 visualization approaches for both experienced and inexperienced surgeons (p < 0.05). Furthermore, the type of surgical technique (manual or FLACS) did not affect the surgical duration for both experienced and inexperienced surgeons (p < 0.05). No intraoperative complications were demonstrated in the current cohort. CONCLUSIONS: The implementation of heads up-3D visualization either through a screen or a head mounted platform for cataract surgery seems to offer similar safety and efficiency as the traditional binocular microscope, and both experienced and inexperienced surgeons demonstrate the same outcomes in terms of safety and efficiency.

Binocularity enhances visual acuity of eyes implanted with multifocal intraocular lenses.

PURPOSE: To investigate the effect of binocularity on long-term visual acuity in patients who have undergone bilateral implantation of a presbyopia-correcting diffractive multifocal intraocular lens (IOL). METHODS: Twenty patients (9 men and 11 women) with an average age of 70 ± 7 years (range: 56 to 78 years) underwent bilateral implantation of a diffractive multifocal IOL (AcrySof IQ ReSTOR IOL, SN60D3; Alcon Laboratories, Inc., Fort Worth, TX). Uncorrected visual acuity was measured monocularly and binocularly on average 26 ± 6 months following implantation in the second eye (range: 17 to 40 months) using the University of Crete European-wide modified Early Treatment Diabetic Retinopathy Study charts at the following distances: (1) 4 m, uncorrected distance visual acuity (UDVA), (2) 66 cm, uncorrected intermediate visual acuity (UIVA), and (3) 33 cm, uncorrected near visual (UNVA). RESULTS: Mean ± standard deviation UDVA was 0.07 ± 0.10 and 0.21 ± 0.12 logMAR (20/23 and 20/32 Snellen) in the better and worse eye, respectively, improving to 0.00 ± 0.09 logMAR (20/20 Snellen) binocularly. Mean ± standard deviation UIVA was 0.18 ± 0.14 and 0.32 ± 0.15 logMAR (20/30 and 20/42 Snellen) in the better and worse eye, respectively, improving to 0.08 ± 0.15 logMAR (20/24 Snellen) binocularly. Mean ± standard deviation UNVA was 0.20 ± 0.09 and 0.32 ± 0.12 logMAR (20/32 and 20/42 Snellen) in the better and worse eye, respectively, improving to 0.11 ± 0.10 logMAR (20/26 Snellen) binocularly. Binocular summation, defined as the difference between the binocular and better eye visual acuity, was found to be statistically significant at all distances: 0.07 ± 0.05 logMAR at 4 m, 0.10 ± 0.11 logMAR at 66 cm, and 0.09 ± 0.08 logMAR at 33 cm. CONCLUSIONS: The results confirm that there is substantial benefit of binocular vision in individuals with bilateral multifocal IOL implantation in terms of increased visual acuity. This effect is evident at all distances.

Time-dependent morphological alterations and viability of cultured human trabecular cells after exposure to Trypan blue.

BACKGROUND: To determine the time-dependent toxicity of Trypan blue at 0.06% concentration in cultured human trabecular meshwork cells. METHODS: Human trabecular meshwork cells cultured in vitro were exposed to Trypan blue and acute toxicity was evaluated. Cells were exposed for 5, 30, 60 s and for 5, 15, 30, 60 min to a commercially available Trypan blue preparation (Vision Blue; DORC International Zuidland, The Netherlands). Morphology was observed by phase-contrast microscopy and cell viability was measured using Hoechst 33342 (Intergen; Purchase, NY, USA) and propidium iodide assays to determine the percentage of living and dead cells. RESULTS: Morphological changes occurred mainly after 5 min of exposure to Trypan blue. Viability was 96.0% ± 3.6%, 94.8% ± 3.5% and 92.5% ± 4.4% after 5, 30 and 60 s of exposure, respectively; a significant toxic effect of Trypan blue was observed after 5, 15, 30 and 60 min of exposure with a viability of 85.0% ± 3.7%, 77.0% ± 6.7%, 70.8% ± 5.9% and 68.3% ± 8.7%, respectively. CONCLUSIONS: Trypan blue is not toxic, in terms of cell viability, over an exposure time of up to 60 s; however, further exposure results in a gradual increase in damage of cultured human trabecular meshwork cells.

Human anterior lens capsule serving as a substrate for human trabecular meshwork cells cultivation.

To investigate if human anterior lens capsule is a suitable substrate for the culture of primary human trabecular meshwork (HTM) cells. Trabecular meshwork cells derived from four human donors were seeded on anterior lens capsules that were prepared from the lenses of donor eyes. Cell morphology and viability were examined at 1, 3, 5 and 7 days. Cell viability was measured based on a two-colour fluorescence assay (membrane-impermeable propidium iodide and membrane permeable Hoechst 33342). Immunocytochemistry studied Zonula occludens-1 (ZO-1), vimentin, tissue transglutaminase (tTgase) and Na(+)/K(+)-adenosine triphosphatase (Na(+)/K(+)-ATPase). Morphology of the cultivated cells followed a typical model while their viability was > 95% in all cases. ZO-1 was found at the cell boundaries of the HTM-AC complex. Vimentin was located at the lateral membranes of the HTM cells. Na(+)/K(+)-ATPase was found at the basolateral membrane of the HTM cells. tTgase was also identified. Anterior lens capsule can be considered as a suitable alternative substrate for cultivation of HTM cells and assist the expansion of existing knowledge about glaucoma pathophysiology and therapy.

Imaging characteristics of delayed surface calcification in hydrophilic intraocular lens models.

We report two cases of opacified explanted intraocular lenses (IOL).The first lens was explanted from a cataract patient, then treated in vitro with trypsin/ethylene-diamine-tetra-acetic acid. The second hydrophilic acrylic IOL was explanted from a patient who had undergone sulphur hexafluoride (SF6) gas endotamponade surgery to repair a retinal detachment.

Interleukin-6 and matrix metalloproteinase expression in the subretinal fluid during proliferative vitreoretinopathy: correlation with extent, duration of RRD and PVR grade.

PURPOSE: To investigate interleukin (IL)-6 protein levels in the subretinal fluid (SRF) of patients with rhegmatogenous retinal detachment (RRD) complicated by proliferative vitreoretinopathy (PVR); to correlate the IL-6 levels with matrix metalloproteinases (MMP)-1, -2, -3, -8, -9 and tissue inhibitor of metalloproteinases (TIMP)-1 with respect to RRD extent, duration and PVR grade. METHODS: Thirty-one SRF samples from 31 eyes of 31 patients with RRD complicated with PVR and five SRF samples from five eyes of five patients suffering from RRD not complicated with PVR were collected during treatment by scleral buckling. Enzyme-Linked Immunosorbent Assay was employed for the measurement of IL-6, MMP-1, -3, -8 and TIMP-1 levels while the enzymatic activity of MMP-2 and MMP-9 was assessed by gelatin zymography. RESULTS: Protein levels of IL-6 (p=0.050), MMP-1 (p=0.001), MMP-3 (p=0.005), MMP-8 (p=0.003), TIMP-1 (p=0.001) as well as enzymatic activity of proMMP-2 (p=0.001), MMP-2 (p=0.023) and MMP-9 (p=0.015), were significantly higher in the SRF of PVR patients compared to controls. IL-6 levels correlated significantly with TIMP-1 (r=0.528, p=0.035). Regarding clinical parameters of the detachment, IL-6 levels correlated with RRD extent (r=0.592, p=0.016), but not with RRD duration (p=0.857) and PVR grade (p=0.594). Regression analysis revealed positive correlations between IL-6 and MMP-2. CONCLUSIONS: There was a significant correlation between IL-6 and TIMP-1 levels in the SRF of PVR patients. The findings of this study are in agreement with relevant studies concerning IL-6 involvement in the modulation of MMP expression and are indicative of IL-6 and MMP activity during PVR, mainly that of MMP-2 and TIMP-1.