Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 738
Filter
1.
Br J Ophthalmol ; 2024 Jul 31.
Article in English | MEDLINE | ID: mdl-39089845

ABSTRACT

AIM: Routine alcohol testing of practicing physicians remains controversial since there are no uniform guidelines or legal regulations in the medical field. Our aim was to quantitatively study the acute and next-morning effects of breath alcohol concentration (BAC)-adjusted alcohol intake on overall simulated surgical performance and microtremor among senior vitreoretinal surgeons. METHODS: This prospective cohort study included 11 vitreoretinal surgeons (>10 years practice). Surgical performance was first assessed using the Eyesi surgical simulator following same-day alcohol consumption producing a BAC reading of 0.06%-0.10% (low-dose), followed by 0.11%-0.15% (high-dose). Dexterity was then evaluated after a 'night out' producing a high-dose BAC combined with a night's sleep. Changes in the total score (0-700, worst-best) and tremor (0-100, best-worst) were measured. RESULTS: Surgeon performance declined after high-dose alcohol compared with low-dose alcohol (-8.60±10.77 vs -1.21±7.71, p=0.04, respectively). The performance during hangover was similar to low-dose alcohol (-1.76±14.47 vs -1.21±7.71, p=1.00, respectively). The performance during hangover tended to be better than after high-dose alcohol (-1.76±14.47 vs -8.60±10.77, p=0.09, respectively). Tremor increased during hangover compared with low-dose alcohol (7.33±21.65 vs -10.31±10.73, p=0.03, respectively). A trend toward greater tremor during hangover occurred compared with high-dose alcohol (7.33±21.65 vs -4.12±17.17, p=0.08, respectively). CONCLUSION: Alcohol-related decline in simulated surgical dexterity among senior vitreoretinal surgeons was dose-dependent. Dexterity improved the following morning but remained comparable to after low-dose alcohol ingestion. Tremor increased during hangover compared with same-day intoxication. Further studies are needed to investigate extrapolations of these data to a real surgical environment regarding patient safety and surgeon performance.

2.
Proc Biol Sci ; 291(2027): 20241388, 2024 Jul.
Article in English | MEDLINE | ID: mdl-39079666

ABSTRACT

Photoreceptor oil droplets (ODs) are spherical organelles placed most commonly within the inner segment of the cone photoreceptors. Comprising neutral lipids, ODs can be either non-pigmented or pigmented and have been considered optically functional in various studies. Among living amphibians, ODs were only reported to occur in frogs and toads (Anura), while they are absent in salamanders and caecilians. Nonetheless, the limited understanding of their taxonomic distribution in anurans impedes a comprehensive assessment of their evolution and relationship with visual ecology. We studied the retinae of 134 anuran species, extending the knowledge of the distribution of ODs to 46 of the 58 currently recognized families, and providing a new perspective on this group that complements the available information from other vertebrates. The occurrence of ODs in anurans shows a strong phylogenetic signal, and our findings revealed that ODs evolved at least six times during the evolutionary history of the group, independently from other vertebrates. Although no evident correlation was found between OD occurrence, adult habits and diel activity, it is inferred that each independent origin involves distinct scenarios in the evolution of ODs concerning photic habits. Furthermore, our results revealed significant differences in the size of the ODs between nocturnal and arrhythmic anurans relative to the length of the cones' outer segment.


Subject(s)
Anura , Biological Evolution , Phylogeny , Animals , Anura/physiology , Lipid Droplets , Bufonidae/physiology , Photoreceptor Cells, Vertebrate/physiology
3.
BMJ Open Ophthalmol ; 9(1)2024 Jul 23.
Article in English | MEDLINE | ID: mdl-39043575

ABSTRACT

OBJECTIVE: To evaluate the efficacy and safety of faricimab compared with other anti-vascular endothelial growth factor (anti-VEGF) agents in treating neovascular age-related macular degeneration (nAMD) patients. METHODS AND ANALYSIS: A systematic review (SR) was conducted up to January 2023. Network meta-analyses (NMA) were performed, including sensitivity and subgroup analyses for naïve population. Outcomes included changes in visual acuity (Early Treatment of Diabetic Retinopathy Study [ETDRS] letters), anatomical changes, frequency of injections and adverse events. The Cochrane Collaboration guidelines and the Confidence in Network Meta-Analysis framework were used for the SR and the certainty of evidence, respectively. RESULTS: From 4128 identified records through electronic databases and complementary searches, 63 randomised controlled trials (RCTs) met the eligibility criteria, with 42 included in the NMA. Faricimab showed a significant reduction in the number of annual injections compared with most fixed and flexible anti-VEGF treatment regimens, while showing no statistically significant differences in visual acuity through ETDRS letter gain, demonstrating a comparable efficacy. Retinal thickness results showed comparable efficacy to other anti-VEGF agents, and inferior only to brolucizumab. Results also showed that more patients treated with faricimab were free from post-treatment retinal fluid compared with aflibercept every 8 weeks, and both ranibizumab and bevacizumab, in the fixed and pro re nata (PRN) assessed schedules. Faricimab showed a comparable safety profile regarding the risk of ocular adverse events and serious ocular adverse events (SOAE), except for the comparison with brolucizumab quarterly, in which faricimab showed a significant reduction for SOAE risk. CONCLUSION: Faricimab showed a comparable clinical benefit in efficacy and safety outcomes, with a reduction in annual injections compared with fixed and flexible anti-VEGF drug regimens, representing a valuable treatment option for nAMD patients. PROSPERO REGISTRATION NUMBER: CRD42023394226.


Subject(s)
Angiogenesis Inhibitors , Intravitreal Injections , Network Meta-Analysis , Vascular Endothelial Growth Factor A , Visual Acuity , Wet Macular Degeneration , Humans , Angiogenesis Inhibitors/therapeutic use , Angiogenesis Inhibitors/adverse effects , Angiogenesis Inhibitors/administration & dosage , Visual Acuity/drug effects , Wet Macular Degeneration/drug therapy , Wet Macular Degeneration/physiopathology , Vascular Endothelial Growth Factor A/antagonists & inhibitors , Treatment Outcome , Antibodies, Monoclonal, Humanized/therapeutic use , Antibodies, Monoclonal, Humanized/adverse effects , Antibodies, Monoclonal, Humanized/administration & dosage
4.
Cir Cir ; 92(3): 324-330, 2024.
Article in English | MEDLINE | ID: mdl-38862104

ABSTRACT

OBJECTIVE: The objective of the study is to compare the optic coherence tomography (OCT) parameters of the healthy and affected sides of patients with idiopathic sudden sensorineural hearing loss (ISSNHL) and to investigate the relationships between these and the improvement in hearing levels. METHODS: A bilateral eye evaluation of patients diagnosed with ISSNHL was performed with OCT. The ganglion cell complex (GCC) and retina nerve fiber layer (RNFL) thickness values were recorded and the differences between the two eyes were examined. RESULTS: An evaluation was made of 39 patients with a mean age of 44.82 ± 14.90 years. The RNFL thickness of the eyes was determined to be mean 89.87 ± 3.65 µm on the affected side and 103.87 ± 3.98 µm on the healthy control side (p = 0.0001). The mean GCC was determined to be mean 90.46 ± 3.49 µm on the affected side and 103.77 ± 3.96 µm on the healthy control side (p = 0.0001). CONCLUSIONS: A statistically significant difference was observed between the healthy and affected eyes of patients with ISSNHL with respect to mean GCC and mean RNFL thickness. OCT could be a useful technique for measuring this neural degeneration.


OBJETIVO: Comparar e investigar los parámetros de la tomografía de coherencia óptica (OCT) de los lados sanos y afectados de pacientes con pérdida auditiva neurosensorial súbita idiopática (PANSI). MÉTODO: La evaluación ocular bilateral de los pacientes diagnosticados con PANSI se realizó con OCT. Se registraron los valores de espesor del complejo de células ganglionares (CCG) y de la capa de fibras nerviosas de la retina (CFNR), y se examinaron las diferencias entre los dos ojos. RESULTADOS: Se evaluaron 39 pacientes, con una edad media de 44.82 ± 14.90 años. Se determinó que el grosor de la CFNR de los ojos era una media de 89.87 ± 3.65 µm en el lado afectado y 103.87 ± 3.98 µm en el lado de control sano (p = 0.0001). Se determinó que el CCG medio era 90.46 ± 3.49 µm en el lado afectado y 103.77 ± 3.96 µm en el lado de control sano (p = 0.0001). CONCLUSIONES: Se encontró una diferencia estadísticamente significativa entre los ojos sanos y afectados de pacientes con PANSI con respecto al CCG medio y al espesor medio de la CFNR. La OCT podría ser una técnica útil para medir esta degeneración neuronal.


Subject(s)
Axons , Nerve Fibers , Tomography, Optical Coherence , Humans , Tomography, Optical Coherence/methods , Adult , Female , Male , Nerve Fibers/pathology , Middle Aged , Axons/pathology , Retinal Ganglion Cells/pathology , Hearing Loss, Sensorineural/diagnostic imaging , Hearing Loss, Sudden/diagnostic imaging , Young Adult
5.
Int J Retina Vitreous ; 10(1): 43, 2024 Jun 14.
Article in English | MEDLINE | ID: mdl-38877585

ABSTRACT

BACKGROUND: Diabetic retinopathy (DR) stands as the foremost cause of preventable blindness in adults. Despite efforts to expand DR screening coverage in the Brazilian public healthcare system, challenges persist due to various factors including social, medical, and financial constraints. Our objective was to evaluate the quality of images obtained with the AirDoc, a novel device, compared to Eyer portable camera which has already been clinically validated. METHODS: Images were captured by two portable retinal devices: AirDoc and Eyer. The included patients had their fundus images obtained in a screening program conducted in Blumenau, Santa Catarina. Two retina specialists independently assessed image's quality. A comparison was performed between both devices regarding image quality and the presence of artifacts. RESULTS: The analysis included 129 patients (mean age of 61 years), with 29 (43.28%) male and an average disease duration of 11.1 ± 8 years. In Ardoc, 21 (16.28%) images were classified as poor quality, with 88 (68%) presenting artifacts; in Eyer, 4 (3.1%) images were classified as poor quality, with 94 (72.87%) presenting artifacts. CONCLUSIONS: Although both Eyer and AirDoc devices show potential as screening tools, the AirDoc images displayed higher rates of ungradable and low-quality images, that may directly affect the DR and DME grading. We must acknowledge the limitations of our study, including the relatively small sample size. Therefore, the interpretations of our analyses should be approached with caution, and further investigations with larger patient cohorts are warranted to validate our findings.

6.
BMJ Case Rep ; 17(5)2024 May 08.
Article in English | MEDLINE | ID: mdl-38719246

ABSTRACT

Cutis marmorata telangiectatica congenita is a rare congenital vascular malformation characterised by cutaneous vascular abnormalities, typically diagnosed at birth or in the early postnatal period. Although typically benign, this disease is associated with other systemic abnormalities, including rare ocular alterations, such as congenital glaucoma, cataracts and retinopathy.This manuscript describes a female infant, who presented with generalised livedo reticularis, a band of alopecia and cutaneous atrophy in the temporal region above the coronal suture. The patient was diagnosed with cutis marmorata telangiectatica congenita by a paediatrician, and an ophthalmological evaluation was requested. A funduscopy examination in both eyes showed temporal and superior retina with avascular areas with new vessels, venous dilations and shunts, and no retinal detachments. Given these findings, we performed retinal photocoagulation laser treatment with excellent results.This case report highlights the importance of early ophthalmological evaluation of children with this disease to prevent secondary complications, such as vitreous haemorrhage and tractional retinal detachment.


Subject(s)
Livedo Reticularis , Skin Diseases, Vascular , Telangiectasis , Humans , Female , Telangiectasis/congenital , Telangiectasis/complications , Telangiectasis/diagnosis , Skin Diseases, Vascular/diagnosis , Skin Diseases, Vascular/complications , Infant , Laser Coagulation/methods , Retinal Vessels/abnormalities , Retinal Vessels/diagnostic imaging , Retina/abnormalities , Retina/diagnostic imaging
7.
Ophthalmol Sci ; 4(4): 100481, 2024.
Article in English | MEDLINE | ID: mdl-38694494

ABSTRACT

Purpose: To evaluate the performance of artificial intelligence (AI) systems embedded in a mobile, handheld retinal camera, with a single retinal image protocol, in detecting both diabetic retinopathy (DR) and more-than-mild diabetic retinopathy (mtmDR). Design: Multicenter cross-sectional diagnostic study, conducted at 3 diabetes care and eye care facilities. Participants: A total of 327 individuals with diabetes mellitus (type 1 or type 2) underwent a retinal imaging protocol enabling expert reading and automated analysis. Methods: Participants underwent fundus photographs using a portable retinal camera (Phelcom Eyer). The captured images were automatically analyzed by deep learning algorithms retinal alteration score (RAS) and diabetic retinopathy alteration score (DRAS), consisting of convolutional neural networks trained on EyePACS data sets and fine-tuned using data sets of portable device fundus images. The ground truth was the classification of DR corresponding to adjudicated expert reading, performed by 3 certified ophthalmologists. Main Outcome Measures: Primary outcome measures included the sensitivity and specificity of the AI system in detecting DR and/or mtmDR using a single-field, macula-centered fundus photograph for each eye, compared with a rigorous clinical reference standard comprising the reading center grading of 2-field imaging protocol using the International Classification of Diabetic Retinopathy severity scale. Results: Of 327 analyzed patients (mean age, 57.0 ± 16.8 years; mean diabetes duration, 16.3 ± 9.7 years), 307 completed the study protocol. Sensitivity and specificity of the AI system were high in detecting any DR with DRAS (sensitivity, 90.48% [95% confidence interval (CI), 84.99%-94.46%]; specificity, 90.65% [95% CI, 84.54%-94.93%]) and mtmDR with the combination of RAS and DRAS (sensitivity, 90.23% [95% CI, 83.87%-94.69%]; specificity, 85.06% [95% CI, 78.88%-90.00%]). The area under the receiver operating characteristic curve was 0.95 for any DR and 0.89 for mtmDR. Conclusions: This study showed a high accuracy for the detection of DR in different levels of severity with a single retinal photo per eye in an all-in-one solution, composed of a portable retinal camera powered by AI. Such a strategy holds great potential for increasing coverage rates of screening programs, contributing to prevention of avoidable blindness. Financial Disclosures: F.K.M. is a medical consultant for Phelcom Technologies. J.A.S. is Chief Executive Officer and proprietary of Phelcom Technologies. D.L. is Chief Technology Officer and proprietary of Phelcom Technologies. P.V.P. is an employee at Phelcom Technologies.

8.
Front Cell Neurosci ; 18: 1343745, 2024.
Article in English | MEDLINE | ID: mdl-38572071

ABSTRACT

Introduction: Platelet-activating factor (PAF), PAF receptor (PAFR), and PAF- synthesis/degradation systems are involved in essential CNS processes such as neuroblast proliferation, differentiation, migration, and synaptic modulation. The retina is an important central nervous system (CNS) tissue for visual information processing. During retinal development, the balance between Retinal Progenitor Cell (RPC) proliferation and differentiation is crucial for proper cell determination and retinogenesis. Despite its importance in retinal development, the effects of PAFR deletion on RPC dynamics are still unknown. Methods: We compared PAFR knockout mice (PAFR-/-) retinal postnatal development proliferation and differentiation aspects with control animals. Electrophysiological responses were analyzed by electroretinography (ERG). Results and discussion: In this study, we demonstrate that PAFR-/- mice increased proliferation during postnatal retinogenesis and altered the expression of specific differentiation markers. The retinas of postnatal PAFR-/- animals decreased neuronal differentiation and synaptic transmission markers, leading to differential responses to light stimuli measured by ERG. Our findings suggest that PAFR signaling plays a critical role in regulating postnatal RPC cell differentiation dynamics during retinal development, cell organization, and neuronal circuitry formation.

9.
Antioxidants (Basel) ; 13(3)2024 Mar 18.
Article in English | MEDLINE | ID: mdl-38539895

ABSTRACT

Visible light refers to the frequencies within the electromagnetic spectrum that humans can see, encompassing radiation with wavelengths falling between 380 nm to 760 nm. The energy of a single photon increases with its frequency. In the retina, photoreceptor cells contain light-sensitive pigments that absorb light and convert it into electrical stimuli through a process known as phototransduction. However, since the absorption spectrum of photoreceptors closely aligns with blue light (ranging from 400 to 500 nm), exposure to high light intensities or continuous illumination can result in oxidative stress within these cells, leading to a loss of their functionality. Apart from photoreceptor cells, the retina also houses photosensitive ganglion cells, known as intrinsically photosensitive retinal ganglion cells (ipRGCs). These cells relay information to the suprachiasmatic nucleus in the brain, playing a crucial role in modulating melatonin secretion, which in turn helps in synchronizing the body's circadian rhythms and responses to seasonal changes. Both, ipRGCs and skin possess a peak sensitivity to blue wavelengths, rendering them particularly susceptible to the effects of excessive blue light exposure. This study delves into the consequences of excessive illumination and/or prolonged exposure to blue light on retinal function and explores its implications for human health.

10.
medRxiv ; 2024 Jan 23.
Article in English | MEDLINE | ID: mdl-38343827

ABSTRACT

Introduction: The Brazilian Multilabel Ophthalmological Dataset (BRSET) addresses the scarcity of publicly available ophthalmological datasets in Latin America. BRSET comprises 16,266 color fundus retinal photos from 8,524 Brazilian patients, aiming to enhance data representativeness, serving as a research and teaching tool. It contains sociodemographic information, enabling investigations into differential model performance across demographic groups. Methods: Data from three São Paulo outpatient centers yielded demographic and medical information from electronic records, including nationality, age, sex, clinical history, insulin use, and duration of diabetes diagnosis. A retinal specialist labeled images for anatomical features (optic disc, blood vessels, macula), quality control (focus, illumination, image field, artifacts), and pathologies (e.g., diabetic retinopathy). Diabetic retinopathy was graded using International Clinic Diabetic Retinopathy and Scottish Diabetic Retinopathy Grading. Validation used Dino V2 Base for feature extraction, with 70% training and 30% testing subsets. Support Vector Machines (SVM) and Logistic Regression (LR) were employed with weighted training. Performance metrics included area under the receiver operating curve (AUC) and Macro F1-score. Results: BRSET comprises 65.1% Canon CR2 and 34.9% Nikon NF5050 images. 61.8% of the patients are female, and the average age is 57.6 years. Diabetic retinopathy affected 15.8% of patients, across a spectrum of disease severity. Anatomically, 20.2% showed abnormal optic discs, 4.9% abnormal blood vessels, and 28.8% abnormal macula. Models were trained on BRSET in three prediction tasks: "diabetes diagnosis"; "sex classification"; and "diabetic retinopathy diagnosis". Discussion: BRSET is the first multilabel ophthalmological dataset in Brazil and Latin America. It provides an opportunity for investigating model biases by evaluating performance across demographic groups. The model performance of three prediction tasks demonstrates the value of the dataset for external validation and for teaching medical computer vision to learners in Latin America using locally relevant data sources.

11.
Stem Cell Rev Rep ; 20(3): 722-737, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38319527

ABSTRACT

Inherited and non-inherited retinopathies can affect distinct cell types, leading to progressive cell death and visual loss. In the last years, new approaches have indicated exciting opportunities to treat retinopathies. Cell therapy in retinitis pigmentosa, age-related macular disease, and glaucoma have yielded encouraging results in rodents and humans. The first two diseases mainly impact the photoreceptors and the retinal pigmented epithelium, while glaucoma primarily affects the ganglion cell layer. Induced pluripotent stem cells and multipotent stem cells can be differentiated in vitro to obtain specific cell types for use in transplant as well as to assess the impact of candidate molecules aimed at treating retinal degeneration. Moreover, stem cell therapy is presented in combination with newly developed methods, such as gene editing, Müller cells dedifferentiation, sheet & drug delivery, virus-like particles, optogenetics, and 3D bioprinting. This review describes the recent advances in this field, by presenting an updated panel based on cell transplants and related therapies to treat retinopathies.


Subject(s)
Bioprinting , Glaucoma , Hematopoietic Stem Cell Transplantation , Retinal Degeneration , Humans , Gene Editing/methods , Retinal Degeneration/genetics , Retinal Degeneration/therapy , Stem Cell Transplantation/methods
12.
Int J Retina Vitreous ; 10(1): 24, 2024 Feb 29.
Article in English | MEDLINE | ID: mdl-38424619

ABSTRACT

BACKGROUND: To verify the correlation between retinal sensitivity (RS) assessed by the microperimetry (MP) and optical coherence tomography (OCT) parameters measured in eyes submitted to pars-plana vitrectomy (PPV) for idiopathic epiretinal membrane (ERM) treatment. METHODS: 43 patients underwent PPV. Best-corrected visual acuity (BCVA) and OCT imaging were acquired preoperatively and 6 months after surgery. The RS values were recorded 6 months after the surgery. Total macular thickness (TMT) measurements and OCT-evaluated structural findings were also analyzed. The MP examination tested 44 points, with direct topographic correspondence with the OCT-ETDRS map. Correlations between BCVA, RS, and OCT parameters were assessed. RESULTS: TMT measurements in patients were significantly thicker preoperatively and reduced after surgery. All patients demonstrated BCVA improvements after surgery. The RS parameters after surgery were significantly lower in patients. For OCT structural analyses, patients with lower RS at the fovea correlated with the preexisting disorganization of retinal inner layers (DRIL). In addition, lower RS values were associated with DRIL, outer retinal changes (ORC), and intraretinal microcysts after surgery. CONCLUSIONS: The RS values after surgery were significantly lower when compared to controls. The DRIL presence before and after surgery, and microcysts and ORC after surgery were related to worse visual outcomes.

13.
Photodiagnosis Photodyn Ther ; 45: 103965, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38218571

ABSTRACT

Retinal lesions, including cotton-wool exudates, microbleeds, vascular occlusions and vasculitis, occur in a minority of Coronavirus Disease-19 (COVID-19) patients. Retinal assessments using retinography can help document these lesions. The objective of this work was to identify retinal changes in patients admitted to the ward with a positive Real Time Quantitative Polymerase Chain Reaction (RT-qPCR) exam for COVID-19. A cross-sectional, observational study was carried out of patients with mild and moderate symptoms admitted to the Hospital de Base in São José do Rio Preto. The Eyer® portable retinal camera (Phelcom® Technologies) was used to evaluate 30 male and 21 female patients. The ages ranged from 21 to 83 years (mean: 47 years). Systemic arterial hypertension was identified in 21 (41.2 %) and diabetes mellitus in 12 (23.5 %) patients. Six (11.7 %) reported worsening visual acuity, however, none of these patients had ocular findings to justify this complaint. Ten patients (19.6 %) had intraretinal hemorrhages; one (1.9 %) had cotton-wool exudates and seven (13.7 %) had dilations of veins. Thirteen patients (25.4 %) had vascular tortuosity and six (11.7 %) had pathological arteriovenous crossings. Portable retinography is useful to evaluate patients admitted to isolation wards due to COVID-19. It is important to remember that some of the patients investigated had comorbidities like diabetic maculopathy and systemic arterial hypertension. Hence, some care should be taken in attributing these observations uniquely to COVID-19 infection.


Subject(s)
COVID-19 , Hypertension , Photochemotherapy , Humans , Female , Male , Young Adult , Adult , Middle Aged , Aged , Aged, 80 and over , Cross-Sectional Studies , Photochemotherapy/methods , Photosensitizing Agents , Hospitals
14.
Int J Mol Sci ; 25(2)2024 Jan 17.
Article in English | MEDLINE | ID: mdl-38256192

ABSTRACT

The retina is the sensory tissue responsible for the first stages of visual processing, with a conserved anatomy and functional architecture among vertebrates. To date, retinal eye diseases, such as diabetic retinopathy, age-related macular degeneration, retinitis pigmentosa, glaucoma, and others, affect nearly 170 million people worldwide, resulting in vision loss and blindness. To tackle retinal disorders, the developing retina has been explored as a versatile model to study intercellular signaling, as it presents a broad neurochemical repertoire that has been approached in the last decades in terms of signaling and diseases. Retina, dissociated and arranged as typical cultures, as mixed or neuron- and glia-enriched, and/or organized as neurospheres and/or as organoids, are valuable to understand both neuronal and glial compartments, which have contributed to revealing roles and mechanisms between transmitter systems as well as antioxidants, trophic factors, and extracellular matrix proteins. Overall, contributions in understanding neurogenesis, tissue development, differentiation, connectivity, plasticity, and cell death are widely described. A complete access to the genome of several vertebrates, as well as the recent transcriptome at the single cell level at different stages of development, also anticipates future advances in providing cues to target blinding diseases or retinal dysfunctions.


Subject(s)
Retinal Diseases , Animals , Humans , Blindness , Health Status , Neuroglia , Neurons , Retina
15.
Mov Disord ; 39(1): 203-209, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38037516

ABSTRACT

BACKGROUND: ATXN2 is the causative gene of spinocerebellar ataxia type 2 (SCA2) and has been implicated in glaucoma pathogenesis. Therefore, studying ocular changes in SCA2 could uncover clinically relevant changes. OBJECTIVE: The aim was to investigate optic disc and retinal architecture in SCA2. METHODS: We evaluated 14 patients with SCA2 and 26 controls who underwent intraocular pressure measurement, fundoscopy, and macular and peripapillary spectral domain optical coherence tomography (SD-OCT). We compared SD-OCT measurements in SCA2 and controls, and the frequency of glaucomatous changes among SCA2, controls, and 76 patients with other SCAs (types 1, 3, 6, and 7). RESULTS: The macula, peripapillary retinal nerve fiber and inner plexiform layers were thinner in SCA2 than in controls. Increased cup-to-disc ratio was more frequent in SCA2 than in controls and other SCAs. CONCLUSIONS: Ocular changes are part of SCA2 phenotype. Future studies should further investigate retinal and optic nerve architecture in this disorder.


Subject(s)
Macula Lutea , Optic Disk , Humans , Optic Disk/pathology , Retinal Ganglion Cells/pathology , Retina/diagnostic imaging , Retina/pathology , Macula Lutea/pathology , Tomography, Optical Coherence/methods
16.
Exp Eye Res ; 238: 109745, 2024 01.
Article in English | MEDLINE | ID: mdl-38043763

ABSTRACT

The epiretinal membrane is a fibrocontractile tissue that forms on the inner surface of the retina, causing visual impairment ranging from mild to severe, and even retinal detachment. Müller glial cells actively participate in the formation of this membrane. Current research is constantly seeking for new therapeutic approaches that aim to prevent or treat cellular dysfunctions involved in the progression of this common fibrosis condition. The Rho GTPases signaling pathway regulates several processes associated with the epiretinal membrane, such as cell proliferation, migration, and contraction. Rho kinase (ROCK), an effector of the RhoA GTPase, is an interesting potential therapeutic target. This study aimed to evaluate the effects of a ROCK inhibitor (Y27632) on human Müller cells viability, growth, cytoskeletal organization, expression of extracellular matrix components, myofibroblast differentiation, migration, and contractility. Müller cells of the MIO-M1 lineage were cultured and treated for different periods with the inhibitor. Viability was evaluated by MTT assay and trypan blue exclusion method, and growth was evaluated by growth curve and BrdU incorporation assay. The actin cytoskeleton was stained with fluorescent phalloidin, intermediate filaments and microtubules were analyzed with immunofluorescence for vimentin and α-tubulin. Gene and protein expression of collagens I and V, laminin and fibronectin were evaluated by rt-PCR and immunofluorescence. Chemotactic and spontaneous cell migration were studied by transwell assay and time-lapse observation of live cells, respectively. Cell contractility was assessed by collagen gel contraction assay. The results showed that ROCK inhibition by Y27632 did not affect cell viability, but decreased cell growth and proliferation after 72 h. There was a change in cell morphology and organization of F-actin, with a reduction in the cell body, disappearance of stress fibers and formation of long, branched cell extensions. Microtubules and vimentin filaments were also affected, possibly because of F-actin alterations. The inhibitor also reduced gene expression and immunoreactivity of smooth muscle α-actin, a marker of myofibroblasts. The expression of extracellular matrix components was not affected by the inhibitor. Chemotactic cell migration showed no significant changes, while cell contractility was substantially reduced. No spontaneous migration of MIO-M1 cells was observed. In conclusion, pharmacological inhibition of ROCK in Müller cells could be a potentially promising approach to treat epiretinal membranes by preventing cell proliferation, contractility and transdifferentiation, without affecting cell viability.


Subject(s)
Epiretinal Membrane , rho-Associated Kinases , Humans , Actins/metabolism , Ependymoglial Cells/metabolism , Vimentin/metabolism , Cell Survival , Epiretinal Membrane/metabolism , Cells, Cultured , Extracellular Matrix/metabolism
17.
Eur J Ophthalmol ; 34(1): NP84-NP89, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37246399

ABSTRACT

PURPOSE: To report the use of intravitreal triamcinolone to treat macular edema associated with isolated perifoveal exudative vascular anomalous complex (PVAC) and resembling lesion (PVAC-RL). METHODS: In this case series, three diabetic patients (3 eyes) with PVAC-RLs and one healthy patient (1 eye) with PVAC lesion associated with cystic spaces underwent three intravitreal injections of aflibercept before switching to one intravitreal triamcinolone injection in each patient. RESULTS: Macular edema improved from 297.5 ± 8.10 µm, at baseline, to 269.2 ± 8.89 µm, after triamcinolone; whereas visual acuity improved from 20/38 to 20/26 (ETDRS). CONCLUSION: PVAC and PVAC-RL are rare and often misdiagnosed lesions that may be associated with decreased vision. Our outcomes suggest that intravitreal injection of triamcinolone may be an effective and affordable treatment for PVAC and PVAC-RL with intraretinal fluid.


Subject(s)
Diabetic Retinopathy , Macular Edema , Humans , Triamcinolone , Macular Edema/diagnosis , Macular Edema/drug therapy , Macular Edema/etiology , Diabetic Retinopathy/diagnosis , Diabetic Retinopathy/drug therapy , Glucocorticoids , Intravitreal Injections , Triamcinolone Acetonide
18.
Eur J Ophthalmol ; 34(2): NP68-NP72, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37671424

ABSTRACT

PURPOSE: To report a case of exudative perifoveal exudative vascular anomalous complex (ePVAC) in a Brazilian healthy patient that underwent a complete resolution after aflibercept intravitreal injections. CASE DESCRIPTION: A 41-year-old healthy Brazilian man complained of acute central vision loss in his right eye (RE). Fundus examination showed a perifoveal hemorrhagic aneurysmal lesion, accompanied by several hard exudates in RE. On fluorescein angiography, these abnormalities showed a progressive hyperfluorescence with surrounding leakage. Optical coherence tomography (OCT) revealed a deep, perifoveal hyporeflective cystic space with a hyperreflective wall and hyperreflective material inside of fibrin-like aspect. Around this aneurism, intraretinal hyporeflective spaces suggestive of exudation were detected. Nor pathological flow signal, or telangiectatic dilations were evidenced on OCT-angiography. Therefore, a diagnosis of exudative ePVAC in RE was hypothesized. After an initial observation, the patient underwent three monthly aflibercept intravitreal injections (0.05 ml/2 mg), with a significative anatomical and functional improvement after two weeks from first dose. On last follow-up at five months from baseline, patient experienced no evidence of new exudation and a stable visual acuity. DISCUSSION: Placental growth factor (PlGF) may impact on pericytes' dropout, and thus on ePVAC development. In contrast to the other anti-VEGF drugs, aflibercept is the only molecule contrasting PlGF. Therefore, aflibercept would act on ePVAC not as an anti-VEGF drug, but rather as an anti-PlGF one. CONCLUSION: This report encouraged the use of aflibercept as a therapeutic option for ePVAC. Further studies are required to confirm our result and the impact of PlGF on ePVAC pathogenesis.


Subject(s)
Receptors, Vascular Endothelial Growth Factor , Vascular Malformations , Male , Humans , Female , Adult , Intravitreal Injections , Brazil , Placenta Growth Factor/therapeutic use , Receptors, Vascular Endothelial Growth Factor/therapeutic use , Recombinant Fusion Proteins/therapeutic use , Fluorescein Angiography/methods , Vascular Malformations/diagnosis , Vascular Malformations/drug therapy , Tomography, Optical Coherence/methods , Angiogenesis Inhibitors/therapeutic use
20.
Arq. neuropsiquiatr ; Arq. neuropsiquiatr;82(4): s00441786022, 2024. graf
Article in English | LILACS-Express | LILACS | ID: biblio-1557136

ABSTRACT

Abstract Henrik and Torsten Sjögren (/'ogrƏn/ or SHOH-grƏn) were two Swedish physicians living in the same period, but completely unrelated, except for their notable contributions to Medicine. The first one described keratoconjunctivitis sicca, afterward called Sjögren's syndrome, and a fishing net aspect retinal pigmentation affecting visual acuity, nowadays known as Sjögren reticular dystrophy. The last one contributed to the understanding of Spielmeyer-Sjögren disease, Marinesco-Sjögren, and Sjögren-Larsson syndromes, all related to genetic disorders and neurological symptoms. In this paper, we aim to describe each disorder, in order to avoid any misunderstanding in diagnosis and for historical record.


Resumo Henrik e Torsten Sjögren (/'ogrƏn/ or SHOH-grƏn) foram dois médicos suecos que viveram na mesma época, mas não tinham nenhuma relação entre si, exceto por suas notáveis contribuições à medicina. O primeiro descreveu a ceratoconjuntivite sicca, posteriormente chamada de síndrome de Sjögren, e uma pigmentação da retina com aspecto de rede de pesca que afeta a acuidade visual, hoje conhecida como distrofia reticular de Sjögren. O último contribuiu para a compreensão da doença de Spielmeyer-Sjögren, das síndromes de Marinesco-Sjögren e Sjögren-Larsson, todas relacionadas a distúrbios genéticos e sintomas neurológicos. Neste artigo, pretendemos descrever cada desordem, a fim de evitar qualquer mal-entendido no diagnóstico e para registro histórico.

SELECTION OF CITATIONS
SEARCH DETAIL