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- Influence of functional variations in genes of neurotrophins and neurotransmitter systems on the development of retinopathy of prematurityPublication . Fevereiro-Martins, Mariza; Santos, Ana Carolina; Marques-Neves, Carlos; Guimarães, Hercília; Bicho, ManuelRetinal neurodevelopment, vascularization, homeostasis, and stress response are influenced by factors such as nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), tyrosine hydroxylase (TH), and erythropoietin (EPO). As retinopathy of prematurity (ROP) is a neurovascular retinal disease, this study analyzed the contributions of NGF (rs6330), BDNF (rs7934165), TH (rs10770141), and EPO (rs507392) genetic functional polymorphisms to the modulation of hematological and biochemical parameters of the first week of life and their association with ROP development. A multicenter cohort of 396 preterm infants (gestational age < 32 weeks or birth weight < 1500 g) was genotyped using MicroChip DNA and iPlex MassARRAY® platform. Multivariate regression followed univariate assessment of ROP risk factors. NGF (GG) genotype was associated with a higher ROP risk (OR = 1.79), which increased further (OR = 2.38) when epistatic interactions with TH (allele C) and BDNF (allele G) were present. Significant circulating biomarker differences, including bilirubin, erythrocytes, monocytes, neutrophils, lymphocytes, and platelet markers, were found between ROP and non-ROP groups, with variations depending on the polymorphism. These findings suggest that NGF (rs6330) and its interactions with related genes contribute to ROP risk, providing valuable insights into the genetic and biological mechanisms underlying the disease and identifying potential predictive biomarkers.
- Relationship between intraocular pressure and anterior lamina cribrosa depth : a cross-sectional observational study in a healthy Portuguese populationPublication . Sousa, David Cordeiro; Leal, Ines; Marques-Neves, Carlos; Pinto, Filomena; Pinto, LuisPurpose: To investigate the association between anterior lamina cribrosa depth (ALCD), determined with enhanced depth imaging spectral-domain optical coherence tomography (EDI-OCT), and intraocular pressure (IOP) in a healthy Portuguese population. Methods: In this cross-sectional observational study conducted between January and July 2015, 2 optic nerve head (ONH)-centered EDI-OCT cross-scans were performed and ALCD was defined as the perpendicular distance between the line connecting both edges of Bruch's membrane opening and the anterior border of the lamina cribrosa at the maximum depth point. A multivariate regression model was performed to assess the association of IOP and ALCD. Results: The studied population included 59 subjects (35 women) with a mean age of 61.7 ± 15.1 years. Mean vertical and horizontal maximum ALCD was 444.5 ± 92.2 μm and 427.6 ± 82.7 μm, respectively. When controlling for age and spherical equivalent, maximum vertical and horizontal ALCD were positively correlated with intraocular pressure (R2>0.20) by 8.58 μm (95% confidence interval [CI] 2.80-14.36 μm; p<0.01) and 8.25 μm (95% CI 2.71-13.78 μm; p<0.01) per mm Hg of IOP, respectively. Conclusions: Our sample of healthy subjects presented a statistically significant positive correlation between IOP and ALCD when controlling for possible confounding factors. These results may trigger further studies to better elucidate the role of IOP in the morphologic and functional dynamics of the ONH.
- Asymptomatic chronic red eye: a surgical technique case reportPublication . Matos, Diogo Bernardo; Guerra, Paulo; José, Patrícia; Ferreira, Rui; Quintas, Ana; Marques-Neves, CarlosIntroduction and importance: Ocular Surface Squamous-cell Neoplasia (OSSN) is an infrequent diagnosis whose clinical suspicion assumes great importance and should not be overlooked. The following case-report aims to describe the diagnosis and treatment of a patient with OSSN whose complaints were mild in comparison to the severity of the disease. The chosen surgical technique was paramount for a disease-free outcome while minimizing the scarring effects of surgical removal. Case presentation: Patient presented mild discomfort right eye and painless persistent hyperaemia. Slit-lamp observation showed a clear diagnosis and lesion's extent evaluated through multimodal imaging. After surgical excision the patient underwent topical ocular treatment with mitomycin-C for a higher margin of safety even before the pathology results were available. Discussion: Ancillary exam technology improvement has allowed a higher margin of safety while determining the extent of OSSN lesions. In the absence of clear diagnostic criteria and guidelines, clinical reasoning and OSSN awareness are critical for timely diagnosis and treatment, as several treatment options are available, allowing an increasing number of patients to be treated non-invasively. In this case-report, we highlight the importance of early-recognition and the reasoning for choosing a combined treatment option with a higher margin of safety. Conclusion: Early recognition and prompt treatment of OSSN lesions is of paramount importance to avoid ocular invasiveness and potentially preclude both ocular and systemic complication. The choice of a combined surgical and medical approach may provide a higher margin of safety for suitable cases. This patient is currently disease-free at 6-month follow-up.
- Retropupillary iris claw intraocular lens implantation in aphakia for dislocated intraocular lensPublication . Faria, Mun Yueh; Ferreira, Nuno Pinto; Pinto, Joana Medeiros; Sousa, David Cordeiro; Leal, Ines; Neto, Eliana; Marques-Neves, CarlosBackground: Nowadays, dislocated intraocular lenses (IOLs) and inadequate capsular support are becoming a challenge for every ophthalmic surgeon. Explantation of dislocated IOL and iris claw IOL (ICIOL) are the techniques that have been used in our ophthalmic department. The aim of this study is to report our technique for retropupillar ICIOL. Methods: This study is a retrospective case series. A total of 105 eyes with dislocated IOL from the patients at the Department of Ophthalmology in Santa Maria Hospital, a tertiary reference hospital in Lisbon, Portugal, from January 2012 until January 2016, had been analyzed. Of these 105 eyes, 66 eyes had dislocated one-piece IOL and 39 eyes had dislocated three-piece IOL. The latter underwent iris suture of the same IOL and were excluded from this study. The remaining 66 eyes with dislocated one-piece IOL underwent pars plana vitrectomy, that is, explantation of dislocated IOL through corneal incision and an implantation of retropupillary ICIOL. Operative data and postoperative outcomes included best corrected visual acuity, IOL position, intraocular pressure, pigment dispersion, clinical signs of endothelial cell loss, and anterior chamber depth. Results: The mean follow-up was 23 months (range: 6–48 months). The mean preoperative best corrected visual acuity was 1.260±0.771 logMAR, and postoperative best corrected visual acuity was 0.352±0.400 logMAR units. Mean vision gain was 0.909 logMar units. The patients had the following complications: 1) retinal detachment was found in one patient, 2) corneal edema was found in three patients, 3) high intraocular pressure was observed in twelve patients, 4) subluxation of the IOL was observed in one patient, and 5) macular edema was found in three eyes. Conclusion: The results demonstrate that retropupillary ICIOL is an easy and effective method for the correction of aphakia in patients not receiving capsule support. The safety of this procedure must be interpreted in the context of a surgery usually indicated in complicated cases.
- A non-infectious uveitis multidisciplinary clinic in a tertiary referral center: clinical impact and added valuePublication . Leal, Ines; Romão, Vasco C.; Sousa Mano, Sofia; Khmelinskii, Nikita; Campanilho-Marques, Raquel; Ponte, Cristina; Macieira, Carla; Oliveira Ramos, Filipa; Vieira De Sousa, Elsa Cristina; Rosa, Carlos Miranda; Rodrigues, Walter; Pinto, Luis; Marques-Neves, Carlos; Fonseca, João EuricoNon-infectious uveitis (NIU) is a group of sight-threatening diseases that generates significant burden for the healthcare systems due to its adverse outcomes, irreversible structural complications in the eye with loss of visual function, limited clinical expertise and low-grade evidence for best practice. The usefulness of multidisciplinary care, specifically close collaboration between Rheumatologists and Ophthalmologists in NIU, has been emphasized in the literature. In this paper, the assessment tools and protocols used in our clinic are depicted and an overview of our activity with a brief description of the patients included in our registry, between 2018 and 2020 is provided. The cohort of 290 patients assessed in our NIU clinic, their demographics, sources of referral, details about immunosuppression treatment, and internal and external collaborations is described. This experience-based manuscript aims to describe the general functioning of our multidisciplinary NIU clinic, highlighting the benefits and drawbacks of multidisciplinary team management in patients with NIU, ultimately initiating a dialogue on what an NIU clinic should be and providing information for newly NIU clinics start-up. In conclusion, establishing a standardized and multidisciplinary clinic in NIU allows to systematically observe and follow-up this infrequent disease at a tertiary hospital level, thus improving quality of care delivery and research avenues.
- Retinopathy of prematurity: a review of pathophysiology and signaling pathwaysPublication . Fevereiro-Martins, Mariza; Marques-Neves, Carlos; Guimarães, Hercília; Bicho, ManuelRetinopathy of prematurity (ROP) is a vasoproliferative disorder of the retina and a leading cause of visual impairment and childhood blindness worldwide. The disease is characterized by an early stage of retinal microvascular degeneration, followed by neovascularization that can lead to subsequent retinal detachment and permanent visual loss. Several factors play a key role during the different pathological stages of the disease. Oxidative and nitrosative stress and inflammatory processes are important contributors to the early stage of ROP. Nitric oxide synthase and arginase play important roles in ischemia/reperfusion-induced neurovascular degeneration. Destructive neovascularization is driven by mediators of the hypoxia-inducible factor pathway, such as vascular endothelial growth factor and metabolic factors (succinate). The extracellular matrix is involved in hypoxia-induced retinal neovascularization. Vasorepulsive molecules (semaphorin 3A) intervene preventing the revascularization of the avascular zone. This review focuses on current concepts about signaling pathways and their mediators, involved in the pathogenesis of ROP, highlighting new potentially preventive and therapeutic modalities. A better understanding of the intricate molecular mechanisms underlying the pathogenesis of ROP should allow the development of more effective and targeted therapeutic agents to reduce aberrant vasoproliferation and facilitate physiological retinal vascular development.
- Tubulointerstitial nephritis and uveitis TINU syndrome : a reviewPublication . Amaro, David; Carreño, Ester; Steeples, Laura R.; Oliveira Ramos, Filipa; Marques-Neves, Carlos; Leal, InesInflammation of renal interstitium and uveal tissue establishes the two components of tubulointerstitial nephritis and uveitis (TINU) syndrome. Although believed to occur more frequently in young females, a broad spectrum of patients can be affected. Both renal and eye disease can be asymptomatic and may not manifest simultaneously, having independent progressions. Renal disease manifests as acute kidney injury and may cause permanent renal impairment. Eye inflammation can manifest in different anatomical forms, most commonly as bilateral anterior uveitis and may progress to a chronic course. TINU syndrome accounts for approximately 1%–2% of uveitis in tertiary referral centres. A literature review covering the clinical features, pathogenesis, diagnosis and treatment is presented.
- A protocol to evaluate retinal vascular response using optical coherence tomography angiographyPublication . Sousa, David Cordeiro; Leal, Ines; Moreira, Susana; Vale, Sónia do; Silva-Herdade, Ana S.; Aguiar, Patrício; Dionísio, Patrícia; Pinto, Luis; Castanho, Miguel A. R. B.; Marques-Neves, CarlosIntroduction: Optical coherence tomography angiography (OCT-A) is a novel diagnostic tool with increasing applications in ophthalmology clinics that provides non-invasive high-resolution imaging of the retinal microvasculature. Our aim is to report in detail an experimental protocol for analyzing both vasodilatory and vasoconstriction retinal vascular responses with the available OCT-A technology. Methods: A commercial OCT-A device was used (AngioVue®, Optovue, CA, United States), and all examinations were performed by an experienced technician using the standard protocol for macular examination. Two standardized tests were applied: (i) the hypoxia challenge test (HCT) and (ii) the handgrip test, in order to induce a vasodilatory and vasoconstriction response, respectively. OCT-A was performed at baseline conditions and during the stress test. Macular parafoveal vessel density of the superficial and deep plexuses was assessed from the en face angiograms. Statistical analysis was performed using STATA v14.1 and p < 0.05 was considered for statistical significance. Results: Twenty-four eyes of 24 healthy subjects (10 male) were studied. Mean age was 31.8 ± 8.2 years (range, 18–57 years). Mean parafoveal vessel density in the superficial plexus increased from 54.7 ± 2.6 in baseline conditions to 56.0 ± 2.0 in hypoxia (p < 0.01). Mean parafoveal vessel density in the deep plexuses also increased, from 60.4 ± 2.2 at baseline to 61.5 ± 2.1 during hypoxia (p < 0.01). The OCT-A during the handgrip test revealed a decrease in vessel density in both superficial (55.5 ± 2.6 to 53.7 ± 2.9, p < 0.001) and deep (60.2 ± 1.8 to 56.7 ± 2.8, p < 0.001) parafoveal plexuses. Discussion: In this work, we detail a simple, non-invasive, safe, and non-costly protocol to assess a central nervous system vascular response (i.e., the retinal circulation) using OCT-A technology. A vasodilatory response and a vasoconstriction response were observed in two physiologic conditions—mild hypoxia and isometric exercise, respectively. This protocol constitutes a new way of studying retinal vascular changes that may be applied in health and disease of multiple medical fields.
- Retinal vascular reactivity in type 1 diabetes patients without retinopathy using optical coherence tomography angiographyPublication . Sousa, David Cordeiro; Leal, Ines; Moreira, Susana; Vale, Sónia do; Silva-Herdade, Ana S.; Aguiar, Patrício; Dionísio, Patrícia; Pinto, Luis; Castanho, Miguel A. R. B.; Marques-Neves, CarlosPurpose: We hypothesize that patients with type 1 diabetes (T1D) may have abnormal retinal vascular responses before diabetic retinopathy (DR) is clinically evident. Optical coherence tomography angiography (OCTA) was used to dynamically assess the retinal microvasculature of diabetic patients with no clinically visible retinopathy. Methods: Controlled nonrandomized interventional study. The studied population included 48 eyes of 24 T1D patients and 24 demographically similar healthy volunteers. A commercial OCTA device (AngioVue) was used, and two tests were applied: (1) the hypoxia challenge test (HCT) and (2) the handgrip test to induce a vasodilatory or vasoconstrictive response, respectively. The HCT is a standardized test that creates a mild hypoxic environment equivalent to a flight cabin. The handgrip test (i.e., isometric exercise) induces a sympathetic autonomic response. Changes in the parafoveal superficial and deep capillary plexuses in both tests were compared in each group. Systemic cardiovascular responses were also comparatively evaluated. Results: In the control cohort, the vessel density of the median parafoveal superficial and deep plexuses increased during hypoxia (F1,23 = 15.69, P < 0.001 and F1,23 = 16.26, P < 0.001, respectively). In the T1D group, this physiological response was not observed in either the superficial or the deep retinal plexuses. Isometric exercise elicited a significant decrease in vessel density in both superficial and deep plexuses in the control group (F1,23 = 27.37, P < 0.0001 and F1,23 = 27.90, P < 0.0001, respectively). In the T1D group, this response was noted only in the deep plexus (F1,23 = 11.04, P < 0.01). Conclusions: Our work suggests there is an early impairment of the physiological retinal vascular response in patients with T1D without clinical diabetic retinopathy.
- Retinopathy of prematurity: contribution of inflammatory and genetic factorsPublication . Fevereiro-Martins, Mariza; Guimarães, Hercília; Marques Neves, Carlos; Bicho, ManuelRetinopathy of prematurity (ROP) is a retinal vasoproliferative disorder that represents an important cause of childhood visual impairment and blindness. Although oxidative stress has long been implicated in ROP etiology, other prenatal and perinatal factors are also involved. This review focuses on current research involving inflammation and genetic factors in the pathogenesis of ROP. Increasing evidence suggests that perinatal inflammation or infection contributes to ROP pathogenesis. Cytokines and chemokines with a fundamental role in inflammatory responses and that significantly contributing to angiogenesis are analyzed. Microglia cells, the retinal-resident macrophages, are crucial for retinal homeostasis, however, under sustained pathological stimuli release exaggerated amounts of inflammatory mediators and can promote pathological neovascularization. Current modulation of angiogenic cytokines, such as treatment with antibodies to vascular endothelial growth factor (anti-VEGF), has shown efficacy in the treatment of ocular neovascularization; however, some patients are refractory to anti-VEGF agents, suggesting that other angiogenic or anti-angiogenic cytokines need to be identified. Much evidence suggests that genetic factors contribute to the phenotypic variability of ROP. Several studies have implicated the involvement of candidate genes from different signaling pathways in the development of ROP. However, a genetic component with a major impact on ROP has not yet been discovered. Most studies have limitations and did not replicate results. Future research involving bioinformatics, genomics, and proteomics may contribute to finding more genes associated with ROP and may allow discovering better solutions in the management and treatment of ROP.