OphthalMimic: A new alternative apparatus without animal tissue for the evaluation of topical ophthalmic drug products.

The necessity of animal-free performance tests for novel ophthalmic formulation screening is challenging. For this, we developed and validated a new device to simulate the dynamics and physical-chemical barriers of the eye for in vitro performance tests of topic ophthalmic formulations. The OphthalMimic is a 3D-printed device with an artificial lacrimal flow, a cul-de-sac area, a support base, and a simulated cornea comprised of a polymeric membrane containing poly-vinyl alcohol 10 % (w/v), gelatin 2.5 % (w/v), and different proportions of mucin and poloxamer, i.e., 1:1 (M1), 1:2 (M2), and 2:1 (M3) w/v, respectively. The support base is designed to move between 0° and 50° to replicate the movement of an eyelid. We challenged the model by testing the residence performance of poloxamer®407 16 % and poloxamer®407 16 % + chitosan 1 % (PLX16CS10) gels containing fluconazole. The test was conducted with a simulated tear flow of 1.0 mL.min-1 for 5 min. The OphthalMimic successfully distinguished PLX16 and PLX16C10 formulations based on their fluconazole drainage (M1: 65 ± 14 % and 27 ± 10 %; M2: 58 ± 6 % and 38 ± 9 %; M3: 56 ± 5 % and 38 ± 18 %). In conclusion, the OphthalMimic is a promising tool for comparing the animal-free performance of ophthalmic formulations.

Terson Syndrome - Clinical Presentation, Management, and Visual Outcomes in a Tertiary Centre.

Purpose: The purpose of this study was to characterize the clinical presentation, management strategy and visual outcomes of patients diagnosed with Terson syndrome and followed in a tertiary centre in Portugal. Patients and Methods: A single-centre retrospective study was performed, based on the survey review of the medical records of every consecutive patient diagnosed with Terson syndrome and followed from January 2018 to August 2021. The change in best-corrected visual acuity (BCVA) from baseline to the final evaluation was the primary outcome. Results: Fifteen eyes from 8 patients (50% female) were included. The mean age at diagnosis was 55±7 years. The neurological event was traumatic brain injury in 37.5% (n=3) and subarachnoid haemorrhage in 62.5% of the patients (n=5). Bilateral intraocular haemorrhage occurred in 875% (n=7) of the patients. Vitreous and preretinal haemorrhages occurred each in 66.7% (n=10), intraretinal in 30% (n=3) and subretinal in 13.3% (n=2) of the eyes. In 40% of the eyes (n=6), spontaneous resolution of intraocular haemorrhage occurred, while PPV was performed in the remaining 60% (n=9). Ocular haemorrhage detection occurred 58.47 ± 40.94 days after the neurological event (range 11 to 121 days). Baseline BCVA was 1.11 ± 1.01 logMAR and improved to 0.32 ± 0.69 logMAR in the follow-up period (p=0.004). A positive correlation was found between initial and final BCVA (Spearman's rho = 0.643, p=0.01). Baseline BCVA of eyes undergoing PPV was lower than of those conservatively managed (1.84±0.72 vs 0.20±0.28 logMAR, p<0.001). However, there were no statistically significant differences in final BCVA after surgery or observation (0.56 ± 0.90 vs 0.04 ± 0.04 logMAR, p=0.149). Longer periods between the neurological and the ophthalmological diagnosis were correlated with worse final BCVA (Spearman's rho = 0.688, p=0.005). Conclusion: Terson syndrome is a potential cause of irreversible visual loss. Diagnosis delay may affect visual prognosis. PPV is indicated when intraocular haemorrhage is dense and does not resolve spontaneously or when visual acuity at presentation is low, allowing for good visual outcomes with minimal complications.

Intravitreal Fluocinolone Acetonide Implant (FAc, 0.19 mg, ILUVIEN®) in the Treatment of Patients with Recurrent Cystoid Macular Edema After Pars Plana Vitrectomy.

INTRODUCTION: Postoperative cystoid macular edema (PCME) is a complication of several ocular procedures, including pars plana vitrectomy (PPV), due to the activation of the inflammatory cascade. The purpose of this case series is to evaluate the effectiveness and safety of fluocinolone acetonide intravitreal implant (FAc, 0.2 µg/day; ILUVIEN®) in the treatment of refractory PCME after successful PPV. METHODS: This retrospective observational case series includes consecutive eyes of patients with recurrent PCME after PPV and treated with a single FAc implant at Centro Hospitalar Universitário de São João, Porto, Portugal. Previous treatments, best-corrected visual acuity (BCVA, ETDRS letters), central macular thickness (CMT, µm), intraocular pressure (IOP, mmHg), and IOP-lowering medication needed were recorded at baseline and during follow-up. Total macular edema resolution was defined as CMT less than 300 µm or a reduction of greater than 20%, and partial macular edema resolution was defined as a reduction of greater than 10%. RESULTS: Nine eyes from nine patients were included. Before FAc implant, all eyes received intravitreal short-action corticosteroids (triamcinolone and dexamethasone implant), with a good response but relapse 1-5 months later. At baseline, BCVA was 55.0 ± 10.6 letters, CMT was 514.9 ± 165.6 µm, and IOP was 15.4 ± 2.4 mmHg with four eyes under IOP-lowering medication. After FAc implant, all eyes achieved edema resolution (eight total and one partial) with a peak gain of 17.2 letters and a maximum decrease of 208.2 µm in CMT. During follow-up (44.0 ± 14.8 months), 66.7% of the eyes kept their macula dry and three showed recurrence after 11, 14, and 28 months, respectively. The maximum IOP registered was 17.0 ± 6.0 mmHg. IOP-lowering regimen was increased in one eye and two additional eyes started hypotensive drops. CONCLUSION: FAc implant can be considered a therapeutic alternative in PCME refractory to other therapies in vitrectomized eyes, reducing the need for repeated treatments.

Gut microbiota and age-related macular degeneration: A growing partnership.

Age-related macular degeneration (AMD) is a leading cause of severe, irreversible vision impairment in developed countries, and its prevalence is rising all over the world, increasing sharply with age. AMD represents an acquired degeneration of the retina that causes significant central visual impairment through a combination of noneovascular and neovascular derangement. The main risk factors for the development of advanced AMD are increasing age, genetic factors, and cigarette smoking; however, the exact pathophysiology of AMD is yet relatively poorly understood. In recent years, the gut microbiota has been intensively studied and linked to several pathologic processes, including ocular diseases. In this sense, the aim of this review is to gather published evidence about the relationship between gut microbiota and AMD.

Scleral Fixation of Akreos AO60 Intraocular Lens Using Gore-Tex Suture: An Eye on Visual Outcomes and Postoperative Complications.

PURPOSE: "In-the-bag" placement of an IOL is the Holy Grail for any cataract surgeon. However, in the absence of capsular integrity, alternative surgical options to place the IOL must be sought. We aim to report the clinical outcomes and safety profile of scleral-fixated Akreos AO60 intraocular lens implantation using Gore-Tex suture, combined with pars plana vitrectomy. METHODS: This is a single-center, retrospective case series descriptive study. Electronic clinical records of all patients subjected to scleral fixation of a Bausch and Lomb Akreos AO60 IOL combined with pars plana vitrectomy, between April 1, 2017, and August 1, 2021, were reviewed. Data concerning age, sex, laterality, past ophthalmological history, pre- and postoperative best-available visual acuity, surgical indication, and intra- and postoperative complications were collected. Measured outcomes were the differences in best-available visual acuity and frequency of postoperative complications. RESULTS: A total of 37 eyes (20 right eyes and 17 left eyes) from 36 patients (16 females and 20 males) were included in the statistical analysis. The mean age at time of surgery was 72.0 ± 12.4 years. The mean follow-up period was 548.9 days (range 39-1564 days). Globally, the mean best-available logMAR visual acuity improved from 1.61 preoperatively (0.025 decimal equivalent) to 0.57 postoperatively (0.3 decimal equivalent), this difference being statistically significant (P < 0.001). Indications for surgery included aphakia due to complicated cataract surgery (24.3%; n = 9); subluxated IOL due to closed trauma (21.6%; n = 8); PEX-related subluxated IOL (16.2%; n = 6); non-traumatic, non-PEX-related subluxated IOL (18.9%; n = 7); subluxated crystalline lens due to closed trauma (8.1%; n = 3); aphakia due to open-globe injury (5.4%; n = 2); silicone-induced IOL opacification (2.7%; n = 1); and aphakia post-endophthalmitis (2.7%; n = 1). Postoperative complications included transient ocular hypertension (27.0%; n = 10), transient corneal edema (18.9%; n = 7), cystoid macular edema (18.9%, n = 7), self-limited hypotension (5.4%, n = 2), self-limited vitreous hemorrhage (2.7%, n = 1), central retinal vein occlusion (2.7%, n = 1), late retinal detachment (2.7%, n = 1), and Akreos IOL opacification (2.7%, n = 1). No suture-related complications were observed. CONCLUSION: There was a statistically significant improvement in visual acuity after scleral fixation of Akreos AO60 intraocular lens using Gore-Tex suture, with no suture-related problems recorded. This procedure seems to be a valuable alternative for posterior chamber IOL placement when secondary IOL implantation is required.

Corneal structure and endothelial morphological changes after uneventful phacoemulsification in type 2 diabetic and nondiabetic patients / Alterações da estrutura e endotélio da cornea após facoemulsificação sem complicações em pacientes diabéticos tipo 2 e não diabéticos

ABSTRACT Purpose: The aim of this study was to compare corneal structure and endothelial morphological changes after uneventful phacoemulsification cataract surgery between type 2 diabetic and nondiabetic patients and to determine the preoperative and intraoperative factors that may predict greater endothelial cell density loss. Methods: Forty-five diabetic pa­tients (45 eyes) and 43 controls (43 eyes) with age-related cataract were enrolled in this prospective observational study. Corneal (thickness and volume) and anterior segment parameters were measured by Scheimpflug tomography; endothelial cell density and morphology (coefficient of variation of cell size, hexagonal cells) were recorded using noncontact specular microscopy. Patients were evaluated preoperatively and at one and six months after surgery. Univariate and multivariate linear regression analyses were performed to evaluate the relationship between demographic, clinical, ocular, and intraoperative parameters and postoperative endothelial cell density changes at six months. Results: Significant postoperative endothelial cell loss occurred one month after surgery in both groups (p<0.001), which remained stable until month 6; there were no differences between patients with and without diabetes mellitus at any time point. The mean postoperative central corneal thickness at one and six months did not change significantly from the mean preoperative value in either group (p>0.05). Multivariate linear regression analysis showed that older age (p=0.042) and higher cataract grades (p=0.001) were significantly associated with greater endothelial cell density reduction at six-month follow-up. Conclusion: This study showed that older age and denser cataracts might be associated with greater endothelial cell density reduction after cataract surgery. Other factors, such as diabetes mellitus and preoperative anterior segment parameters, did not influence postoperative changes in endothelial cell density.

RESUMO Objetivo: Comparar a estrutura da córnea e as alterações mor­fológicas endoteliais após cirurgia de catarata por facoemulsificação sem intercorrências entre pacientes com diabetes mellitus tipo 2 e não diabéticos; e determinar quais fatores pré e intra-operatórios relacionados com a maior redução da densidade celular endotelial. Métodos: Quarenta e cinco diabéticos (45 olhos) e 43 (43 olhos) controlos com catarata relacionada à idade foram incluídos neste estudo observacional prospectivo. Os parâmetros da córnea (espessura e volume) e do segmento anterior foram medidos pela tomografia Scheimpflug; a densidade e morfologia celular endotelial (coeficiente de variação do tamanho das células, células hexagonais) foram registrados usando microscopia especular não contato. Os pacientes foram avaliados no pré-operatório, 1 e 6 meses após a cirurgia. Foi realizada uma análise de regressão linear uni e multivariada para avaliar a relação entre os parâmetros demográficos, clínicos, oculares e intra-operatórios com a redução da densidade celular endotelial aos 6 meses. Resultados: Nos dois grupos houve uma perda significativa de células endoteliais ao 1º mês pós-ope­ratório (p<0,001), que permaneceu estável até ao 6º mês; sem diferenças estatisticas entre os grupos diabetes mellitus e não diabetes mellitus em qualquer avaliação. A espessura média da córnea no pós-operatório central aos 1 e 6 meses não mudou significativamente em relação ao valor médio pré-operatório nos dois grupos (p>0.05). A análise de regressão multivariada linear mostrou que a idade avançada (p=0.042) e os graus mais elevados de catarata (p=0.001) foram significativamente associados à maior redução densidade celular endotelial aos 6 meses de seguimento. Conclusão: Este estudo mostrou que a idade avançada e as cataratas mais densas podem predispor a uma maior redução densidade celular endotelial após a cirurgia de catarata. Outros fatores, como diabetes mellitus e parâmetros pré-operatórios do segmento anterior, não influenciaram significativamente as alterações pós-operatórias da densidade celular endotelial.

Corneal structure and endothelial morphological changes after uneventful phacoemulsification in type 2 diabetic and nondiabetic patients.

PURPOSE: The aim of this study was to compare corneal structure and endothelial morphological changes after uneventful phacoemulsification cataract surgery between type 2 diabetic and nondiabetic patients and to determine the preoperative and intraoperative factors that may predict greater endothelial cell density loss. METHODS: Forty-five diabetic pa-tients (45 eyes) and 43 controls (43 eyes) with age-related cataract were enrolled in this prospective observational study. Corneal (thickness and volume) and anterior segment parameters were measured by Scheimpflug tomography; endothelial cell density and morphology (coefficient of variation of cell size, hexagonal cells) were recorded using noncontact specular microscopy. Patients were evaluated preoperatively and at one and six months after surgery. Univariate and multivariate linear regression analyses were performed to evaluate the relationship between demographic, clinical, ocular, and intraoperative parameters and postoperative endothelial cell density changes at six months. RESULTS: Significant postoperative endothelial cell loss occurred one month after surgery in both groups (p<0.001), which remained stable until month 6; there were no differences between patients with and without diabetes mellitus at any time point. The mean postoperative central corneal thickness at one and six months did not change significantly from the mean preoperative value in either group (p>0.05). Multivariate linear regression analysis showed that older age (p=0.042) and higher cataract grades (p=0.001) were significantly associated with greater endothelial cell density reduction at six-month follow-up. CONCLUSION: This study showed that older age and denser cataracts might be associated with greater endothelial cell density reduction after cataract surgery. Other factors, such as diabetes mellitus and preoperative anterior segment parameters, did not influence postoperative changes in endothelial cell density.

Endophthalmitis following Intravitreal Injection, Cataract Surgery, and Vitrectomy: Clinical Features and Visual Outcomes.

PURPOSE: To describe and compare the clinical features and visual outcomes of endophthalmitis following intravitreal injections (IVI), cataract surgery, and pars plana vitrectomy (PPV). METHODS: This is a single-centre, retrospective study. All included patients had acute postoperative endophthalmitis secondary to one of these three procedures. Visual acuity (VA), comorbidities, time to presentation, and treatment were assessed. The primary outcome was visual outcome. A poor outcome was considered if final VA was worse than or equal to counting fingers (CF) and a good outcome was classified as VA better than CF. RESULTS: Over 12 years, a total of 61 patients were included. Twenty-seven cases were post-cataract endophthalmitis; twenty-five were post-IVI and nine post-PPV. Endophthalmitis post-PPV had a worse visual outcome (88.9% of patients with VA worse than or equal to CF 95% CI 51.3 to 100.0%) than endophthalmitis following cataract surgery (25.9% of patients with VA worse than or equal to CF 95% CI 11.0 to 39.9%) and the IVI subgroup (44.0% of VA worse than or equal to CF 95% CI 24.0 to 67.0%) (p=0.001 and p=0.047). There were no significant differences in the proportion of patients with a poor visual outcome between endophthalmitis following cataract surgery and IVI (p=0.171). CONCLUSIONS: The number of patients with poor visual outcomes following acute endophthalmitis was similar in endophthalmitis following IVI and cataract surgery, but better than endophthalmitis following vitrectomy.

Macular Changes in a Mucopolysaccharidosis Type I Patient with Earlier Systemic Therapies.

PURPOSE: To describe retinal findings in a patient with mucopolysaccharidosis type I (MPS I) that underwent an early treatment with hematopoietic stem cell transplantation (HSCT) and enzyme replacement therapy (ERT). Case Report. We describe a case of a 12-year-old female with a biochemical and genetic diagnosis of MPS I. She underwent HSCT and ERT on the first year of life. The visual acuity was 5/10 in both eyes and she had bilateral grade 2 corneal haze. Spectral domain optical coherence tomography (SD-OCT) revealed thickening of the external limiting membrane (ELM) at the fovea. In the parafoveal and perifoveal regions, SD-OCT displayed a loss of the interdigitation, ellipsoid, and myoid zones and of the ELM accompanied by progressive thinning of the outer nuclear layer. Fundus infrared imaging revealed a hyperreflective ring centred on the fovea and hyporeflective areas in temporal parafoveal regions in both eyes. En face OCT imaging revealed two hyperreflective rings on the outer retinal level. CONCLUSION: This patient developed macular changes with foveal deposition of hyperreflective material and parafoveal thinning, despite early systemic treatment. Systemic therapies can provide an increase in life expectancy and stabilize visual acuity and corneal clouding, although their effect on retinal degeneration is unknown.

Long-term progression of geographic atrophy in age-related macular degeneration does the phakic status matter?

PURPOSE: To assess the long-term risk of geographic atrophy (GA) progression after cataract surgery. METHODS: Subjects with GA secondary to AMD followed for at least 1 year with fundus autofluorescence imaging and with at least two visits at our centre were included. Patients with wet AMD, disciform scar, past history of intravitreal injections or laser treatment, other maculopathies and with poor quality images were excluded. GA area at baseline and at follow-up visit was measured. Three study groups were defined according to their phakic status: (A) pseudophakia, (B) phakic and (C) phacoemulsification surgery performed during the study. Differences of GA area progression were compared between these study groups. In addition, comparison between GA progression rate in group (C) before and after the surgery was performed. The enlargement rate (ER) was calculated for lesion size after transforming the measurements to the square-root scale. RESULTS: A total of 92 eyes of 92 patients were enrolled. Median follow-up time was 4 [1-10] years. Regarding the eye's phakic status, 29 (31.5%) were pseudophakic and 63 (68.5%) were phakic; of these, 22 underwent phacoemulsification during the study. Overall, the median baseline and follow-up area of GA were 1.42 [0.04-32.10] mm2 and 6.48 [0.25-47.40] mm2, respectively. The ER was similar between phakic and pseudophakic eyes (0.18 [0.01-1.03] vs 0.15 [0.01-0.65] mm/year, p = 0.62). In patients that underwent cataract surgery during the study, the GA ER remained stable (0.13 [0.01-0.92] vs 0.14 [0.01-0.63] mm/year, p = 0.43). CONCLUSION: These results suggest that cataract surgery does not increase the risk of pre-existing GA progression. Therefore, cataract surgery seems safe and a potential therapeutic weapon to improve visual acuity and consequently quality of life in GA patients.

Off-Label Use of 0.19 mg Fluocinolone Acetonide Intravitreal Implant: A Systematic Review.

Corticosteroids are used in a variety of ophthalmological diseases. One challenge faced by ophthalmologists is to deliver corticosteroids to the posterior segment of the eye with efficacy and safety. Sustained-release corticosteroid implants may be the answer to this problem. The 0.19 mg fluocinolone acetonide (FAc) implant (Iluvien®) releases FAc for 36 months, and it is approved for the treatment of diabetic macular edema (DME) and noninfectious uveitis. We decided to do a systematic review to acknowledge in which other diseases FAc implant is being used off-label. A literature search was performed in the following three electronic databases: PubMed, Scopus, and Web of Science (from January 1st, 2000, to September 20th, 2020), using the following query: ("Fluocinolone Acetonide" OR Iluvien®) AND ("eye" OR "ocular" OR "intravitreal)." A total of 11 papers were included, and the use of FAc implant was analyzed in the following diseases: radiation-induced maculopathy (RM); paraneoplastic visual syndromes (melanoma-associated retinopathy (MAR) and cancer-associated retinopathy (CAR)); Sjogren's syndrome-related keratopathy; retinal vein occlusion (RVO); cystoid macular edema (CME); diabetic retinal neurodegeneration (DRN); and retinitis pigmentosa (RP). FAc implant may be a potential treatment for these diseases; however, the level of scientific evidence of the included studies in this review is limited. Further studies with larger cohorts and longer follow-ups are needed to validate this data.

Predicting retinal pigment epithelium remodelling and its functional impact.

PURPOSE: To identify predictive factors for RPE tear remodelling and its correlation with functional and morphological outcomes. METHODS: Retrospective longitudinal study of patients with retinal pigment epithelium (RPE) tears secondary to age-related macular degeneration (AMD). Imaging was performed using spectral-domain optical coherence tomography (SD-OCT) and fundus autofluorescence (FAF). RPE layer integrity in the RPE-denuded area was examined with SD-OCT, and variation in the RPE-denuded homogeneous hypofluorescent area was examined with FAF over time for each case (eye). Patients were divided in two groups, according to the presence (Rem) or absence (No Rem) of evidence of RPE tear remodelling. Data were collected at three different time points: at baseline (at diagnosis of exudative AMD), at RPE tear diagnosis, and at the last available follow-up. Using SD-OCT, the following parameters were evaluated: type of CNV, type of PED and its dimensions, presence of subretinal (SRF) or intraretinal (IRF) fluid, central retinal thickness (CRT), presence and location of hyperreflective dots, and dimension and location of RPE tear. RESULTS: This study included 32 eyes from 31 patients (19 female and 12 male), with RPE tears secondary to AMD. RPE remodelling after tear development was evident in 17 (53.1%) eyes after 7 [1-59] months. Anatomical recovery was associated with a younger age at RPE tear diagnosis (73 ± 7 vs. 81 ± 7 years old, p=0.01), smaller and narrower retinal pigment epithelial detachment (PED) at tear diagnosis (height 369 vs. 602 µm, p=0.02; width 2379 vs. 3378 µm, p=0.04), and the presence of SRF at tear diagnosis (94% vs. 53%, p=0.02). After adjusting for other covariates, a younger age at RPE tear diagnosis maintained significant association with RPE tear remodelling. RPE tear remodelling did not correlate with a better visual outcome at last follow-up (43 ± 22.8 vs. 34 ± 23.8 ETDRS letters, p=0.30). Final VA was directly proportional to VA at tear diagnosis (r= 0.654; p<0.001) and correlated negatively with PED width at tear diagnosis (r = -0.388; p=0.03). CONCLUSION: RPE remodelling was evident in half of our sample and was associated with a younger age, smaller and narrower PED at RPE tear diagnosis, and presence of SRF also at tear diagnosis. Nevertheless, this structural recovery did not result in a better functional outcome.

Gastric Bypass Improves Microvascular Perfusion in Patients with Obesity.

PURPOSE: Basic science research has shown that obesity is associated with microvascular endothelial dysfunction. However, whether bariatric surgery impacts the microvascular networks has yet to be explored. This study sought to evaluate the impact of gastric bypass in the retinal microvasculature. METHODS: Patients with obesity (BMI ≥ 35 kg/m2) scheduled to gastric bypass were consecutively recruited and included in the study. Patients were evaluated before surgery and 6-12 months after the intervention. Macular microvascular properties were evaluated using optical coherence tomography (OCT) angiography. Foveal avascular zone area, perimeter, circularity, and foveal and perifoveal vascular density (in both superficial and deep vascular plexus) were computed. RESULTS: In total, 40 eyes from 20 patients were included (30% male, mean BMI 43.4 ± 4.5 kg/m2 (range 35.7-51.4). From these, 45% were diabetic before bariatric surgery. After surgery, there was a significant increase in foveal avascular zone circularity (from 0.85 ± 0.09 to 0.92 ± 0.07, p = 0.001) and vascular density in perifoveal deep vascular plexus (from 0.69 ± 0.12 to 0.73 ± 0.12; p = 0.04), whereas foveal avascular zone perimeter decreased (from 2.34 ± 0.37 to 2.20 ± 0.35 mm, p = 0.007). Preoperative diabetic status was not a predictor of microvascular retinal changes after bariatric surgery. However, after multivariate adjustments, the increased drop in HbA1c after the surgery remained associated with the increase in perifoveal vascular density in the deep vascular plexus (B = 0.05; 95% CI 0.05-0.10; p = 0.03). CONCLUSIONS: Gastric bypass improves retinal microvascular perfusion as demonstrated by the increased parafoveal vascular density in the deep vascular plexus, increased foveal avascular zone circularity, and decreased foveal avascular zone perimeter.

Incidence of endophthalmitis after intravitreal injection with and without topical antibiotic prophylaxis.

PURPOSE: The purpose was to compare the incidence of endophthalmitis after intravitreal injection with and without topical antibiotic prophylaxis. METHODS: This is a single-center, retrospective case-control study. All patients treated with intravitreal injection of ranibizumab, bevacizumab, aflibercept, or corticosteroids for a variety of retinal vascular diseases between 1 October 2014 and 30 November 2018 were included. The total number of patients and injections were determined from a review of billing code and practice management records. Endophthalmitis cases were determined from billing records and then confirmed with chart review. A 24-month period when topical antibiotics were prescribed after intravitreal injection was compared with a 24-month period when topical antibiotics were not prescribed. RESULTS: Between 1 October 2014 and 30 November 2018, a total of 33,515 intravitreal injections were performed and 13 cases of post-intravitreal injection endophthalmitis were identified (incidence rate of 0.0388%; 95% confidence interval, 0.0217%-0.0644%) or approximately 1 case for every 2578 intravitreal injections. Between 1 October 2014 and 31 October 2016, while topical antibiotic prophylaxis was used postoperatively, 14,828 intravitreal injections were performed and 5 cases of endophthalmitis were reported (0.0337%; 95% confidence interval, 0.0129%-0.0739%). Between 1 November 2016 and 30 November 2018, while no prophylaxis was used, 18,687 intravitreal injections were performed and 8 cases of endophthalmitis were identified (0.0428%; 95% confidence interval, 0.0202%-0.0808%). There were no statistical differences in the incidence rates between the two groups (p = 0.675). CONCLUSION: The incidence rate of endophthalmitis in the group with topical antibiotic prophylaxis after intravitreal injection was similar to the group with no prophylaxis. Changing the current clinical practice to no antibiotic prophylaxis had no effect on the incidence of endophthalmitis.

Baseline visual acuity and interdigitation zone as predictors in idiopathic epiretinal membranes: A retrospective cohort study.

OBJECTIVE: Determine which functional and anatomical characteristics may be predictors of final visual acuity in patients with idiopathic ERM (iERM) submitted to pars plana vitrectomy (PPV) with ERM and internal and internal limiting membrane (ILM) peeling. DESIGN: Retrospective cohort study. SUBJECTS: Patients with iERM submitted to PPV between 2016 and 2017. METHODS: Data regarding the best-corrected visual acuity (BCVA) and the characteristics of the retinal layers observed in SD-OCT were collected preoperatively and until 12 months postoperatively. Central macular thickness (CMT), disorganization of the retinal inner layers (DRIL), outer nuclear layer (ONL) thickness, integrity of subfoveal external limiting membrane (ELM), ellipsoid zone (EZ), and interdigitation zone (IZ) were evaluated. RESULTS: A total of 128 eyes with iERM from 121 patients were included. BCVA improved significantly (p < 0.001). Significant improvement of BCVA, CMT, DRIL, ONL, ELM, and EZ were obtained. The final IZ was not different from baseline until the end of the study. A significant correlation was observed between the baseline BCVA, EZ, IZ, and the postoperative BCVA (p < 0.001). However, only the baseline BCVA and the integrity of the subfoveal baseline IZ were predictive factors for final BCVA (p < 0.005 and p < 0.001, respectively). CONCLUSION: PPV provides a significant improvement of BCVA and retinal anatomy recovery in iERM eyes. Baseline IZ didn't change during the 12 months following surgery. Baseline BCVA and subfoveal IZ at baseline were prognostic factors for the final BCVA.

IMPLICATIONS OF THE MORPHOLOGIC PATTERNS OF TYPE 1 MACULAR NEOVASCULARIZATION ON MACULAR ATROPHY GROWTH ON PATIENTS UNDER ANTI-VASCULAR ENDOTHELIAL GROWTH FACTOR TREATMENT.

PURPOSE: To evaluate the correspondence between macular atrophy (MA) progression and Type 1 macular neovascularization morphology during long-term anti-vascular endothelial growth factor treatment for exudative neovascular age-related macular degeneration. METHODS: Retrospective review of consecutive patients with complete retinal pigment epithelium and outer retina atrophy overlying or in the proximity of macular neovascularization. The assessment of MA was based on spectral domain optical coherence tomography, en-face near infra-red imaging and fundus autofluorescence. Macular neovascularization blood flow morphology was evaluated by swept-source optical coherence tomography-angiography. Qualitative features were categorized per ETDRS sector as: immature, mature; and hypermature pattern. An automatic analysis was designed in MATLAB coding language to compute MA per ETDRS. Measurements were compared between the baseline and the last follow-up visit. RESULTS: Twenty eyes from 20 patients were included; the mean age was 85.4 (8.3) years. The median follow-up was 1.85 (1.0-2.4) years and the median anti-vascular endothelial growth factor injection rate during follow-up was 4.0 (2.0-5.0) injections/year. During follow-up, sectors with persistence of an immature blood flow pattern had a lower MA growth rate than sectors with mature macular neovascularization flow patterns (P = 0.001). CONCLUSION: The presence of an immature blood flow pattern on optical coherence tomography-angiography is associated with a lower progression rate of MA.

Evaluation of the different thresholding strategies for quantifying choriocapillaris using optical coherence tomography angiography.

BACKGROUND: In this paper, we evaluate the different thresholding strategies that have been used for the quantification of the choriocapillaris (CC) and explore their repeatability and the interchangeability of the measurements resulting from its application. METHODS: Observational study. Eighteen eyes from nine healthy volunteers aged >18 years were imaged four consecutive times with a SD-OCTA system (Heidelberg Engineering, Germany) using a 10°×10° high-resolution protocol centered on the fovea. Projection artifacts were removed, and the CC was bracketed between 10 and 30 µm below Bruch's membrane. For the quantification of CC, we used four flow deficits (FD) parameters: FD number, mean FD size, total FD area and FD density. We performed a systematic review of literature to collect the thresholding methods that have been used for the quantification of CC. The CC quantification parameters were then evaluated after applying each of the thresholding strategies. Intraclass correlation coefficient (ICC) and Pearson's correlation analysis were used to compare the repeatability and interchangeability among the different thresholding strategies for quantifying the CC. RESULTS: A total of 72 optical coherence tomography angiography (OCTA) examinations were considered. The systematic review allowed us to conclude that three local thresholding strategies (Phansalkar, mean and Niblack) and three global thresholding strategies (mean, default, Otsu) have been used for CC quantification. These strategies were evaluated in our observational study. We found a high agreement within the same method in the quantification of FD number, mean FD size, total FD area and FD density but a poor agreement with different strategies. Local strategies achieved a significantly superior ICC than global ones in CC quantification. CONCLUSIONS: In conclusion, the interchangeability of the CC quantification using different thresholding strategies is low, and direct comparisons should not be performed. Local thresholding strategies are significantly superior to global ones for quantifying CC and should be preferred. There is an unmet need for a uniform strategy to quantify CC in future studies.

Bariatric Surgery Induces Retinal Thickening Without Affecting the Retinal Nerve Fiber Layer Independent of Diabetic Status.

PURPOSE: Obese patients have neurodegeneration of the optic nerve demonstrated by decreased peripapillary nerve fiber layer. Whether bariatric surgery reverses this neurodegenerative process has not been explored. We aimed to evaluate the impact of bariatric surgery in the structure of the retina and optic nerve. METHODS: Multicentric observational study. Obese patients scheduled for bariatric surgery were consecutively recruited and included in the study and evaluated before and 6-12 months after the intervention. The retinal structure was evaluated as retinal thickness in the different retinal layers in the foveal, perifoveal, and parafoveal regions using optical coherence tomography. Choroidal thickness and optic nerve retinal nerve fiber layer thickness were also evaluated. RESULTS: Eighty eyes from 40 participants were included. Globally, we found a significant thickening of the retina after bariatric surgery (foveal: 273.5 (21.5) µm vs 280.0 (28.8) µm, p < 0.001; parafoveal 332.4 ± 17.8 µm vs 336.6 ± 15.9 µm, p = 0.003; perifoveal: 293.4 ± 13.8 µm vs 295.7 ± 14.9 µm; p = 0.001), whereas no significant differences were found for the ganglion cell layer, choroid, or peripapillary nerve fiber layer thickness. The retinal thickening was confined to inner retinal layers and was independent of the diabetic status of the patients. After multivariate adjustment, HbA1c variation, preoperative C-peptide, preoperative hypertension, preoperative OSA, and preoperative LDL and TG levels seem to be clinical predictors of retinal thickening. CONCLUSIONS: We found a significant thickening of the retina after bariatric surgery that was independent of the diabetic status. The thickening was confined to inner retinal layers and may represent and improve perfusion. The peripapillary nerve fiber layer remained unchanged after the surgery.

SARS-COV-2 in Ophthalmology: Current Evidence and Standards for Clinical Practice.

INTRODUCTION: COVID-19 is caused by the coronavirus SARS-CoV-2. Ocular manifestations have been reported including conjunctivitis and retinal changes. Therefore, it is of the utmost importance to clarify eye involvement in COVID-19 in order to help with its diagnosis and to further prevent its transmission. The purpose of this review is to describe the structure and transmission of SARS-CoV-2, reported ocular findings and protection strategies for ophthalmologists. MATERIAL AND METHODS: Literature search on PubMed for relevant articles using the keywords 'COVID-19', 'coronavirus', and 'SARS-CoV-2' in conjunction with 'ophthalmology' and 'eye'. Moreover, official recommendations of ophthalmological societies were reviewed. RESULTS: Although the conjunctiva is directly exposed to extraocular pathogens, and the mucosa of the ocular surface and upper respiratory tract are connected by the nasolacrimal duct, the eye is rarely involved in human SARS-CoV-2 infection and the SARS-CoV-2 RNA positive rate by RT-PCR test in tears and conjunctival secretions from patients with COVID-19 is also extremely low. DISCUSSION: The eye can be affected by SARS-CoV-2, which is supported by some reports of conjunctivitis and retinal changes, but its role in the spread of the disease is still unknown. CONCLUSION: Given the current scarce evidence, more research is needed to clarify the relationship between SARS-CoV-2 and the eye.

Introdução: COVID-19 é o nome atribuído à doença causada pelo novo coronavírus - SARS-CoV-2. Esta infeção rapidamente atingiu uma disseminação mundial, face ao aumento da globalização e adaptação do vírus a ambientes distintos. Foram descritas manifestações oftalmológicas em doentes com COVID-19, nomeadamente, conjuntivite e alterações retinianas. Assim, é fundamental esclarecer o envolvimento ocular na COVID-19, contribuindo para o seu diagnóstico precoce e limitando a sua transmissão. O objetivo desta revisão é descrever a estrutura e o modo de transmissão do SARS-CoV-2, assim como manifestações oculares reportadas e estratégias de proteção para oftalmologistas. Material e Métodos: Revisão dos artigos relevantes publicados na PubMed usando as palavras-chave 'COVID-19', 'coronavirus' e 'SARS-CoV-2' em associação com as palavras 'ophthalmology' e 'eye'. Além disso, foi feita uma revisão das recomendações oficiais de várias sociedades oftalmológicas a nível mundial. Resultados: Apesar da conjuntiva estar diretamente exposta a patógenos exógenos, e da mucosa da superfície ocular e do trato respiratório superior estarem conectados pelo canal nasolacrimal, o olho raramente parece ser afetado pelo SARS-CoV-2. A infeção por SARS-CoV-2 e a taxa de positividade para a pesquisa do RNA do SARS-CoV-2 pelo teste de RT-PCR em lágrimas e secreções conjuntivais de pacientes com COVID-19 também são extremamente baixas. Discussão: O olho pode ser afetado pelo SARS-CoV-2, dada a descrição de casos de conjuntivite e alterações retinianas, mas o seu papel na disseminação da doença ainda é desconhecido. Conclusão: Dada a escassa evidência atual, são necessários mais estudos para esclarecer a relação entre o SARS-CoV-2 e o globo ocular.