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1.
Int J Mol Sci ; 22(17)2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34502541

RESUMO

Inhibitor of DNA binding (Id) genes comprise a family of four helix-loop-helix (HLH) transcriptional inhibitors. Our earlier studies revealed a role for ID2 within the circadian system, contributing to input, output, and core clock function through its interaction with CLOCK and BMAL1. Here, we explore the contribution of ID4 to the circadian system using a targeted disruption of the Id4 gene. Attributes of the circadian clock were assessed by monitoring the locomotor activity of Id4-/- mice, and they revealed disturbances in its operation. Id4-mutant mice expressed a shorter circadian period length, attenuated phase shifts in responses to continuous and discrete photic cues, and an advanced phase angle of entrainment under a 12:12 light:dark cycle and under short and long photoperiods. To understand the basis for these properties, suprachiasmatic nucleus (SCN) and retinal structures were examined. Anatomical analysis reveals a smaller Id4-/- SCN in the width dimension, which is a finding consistent with its smaller brain. As a result of this feature, anterograde tracing in Id4-/- mice revealed retinal afferents innovate a disproportionally larger SCN area. The Id4-/- photic entrainment responses are unlikely to be due to an impaired function of the retinal pathways since Id4-/- retinal anatomy and function tested by pupillometry were similar to wild-type mice. Furthermore, these circadian characteristics are opposite to those exhibited by the Id2-/- mouse, suggesting an opposing influence of the ID4 protein within the circadian system; or, the absence of ID4 results in changes in the expression or activity of other members of the Id gene family. Expression analysis of the Id genes within the Id4-/- SCN revealed a time-of-day specific elevated Id1. It is plausible that the increased Id1 and/or absence of ID4 result in changes in interactions with bHLH canonical clock components or with targets upstream and/or downstream of the clock, thereby resulting in abnormal properties of the circadian clock and its entrainment.


Assuntos
Relógios Circadianos/genética , Proteínas Inibidoras de Diferenciação/genética , Proteínas Circadianas Period/genética , Fotoperíodo , Retina/metabolismo , Núcleo Supraquiasmático/metabolismo , Animais , Ritmo Circadiano , Expressão Gênica , Proteínas Inibidoras de Diferenciação/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Atividade Motora/genética , Atividade Motora/fisiologia , Proteínas Circadianas Period/metabolismo , Retina/anatomia & histologia , Núcleo Supraquiasmático/anatomia & histologia
2.
Malawi Med J ; 33(1): 15-20, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-34422229

RESUMO

Purpose: To evaluate the clinical and socio-demographic profile of patients living with glaucoma and receiving care in a tertiary eye center in Zimbabwe. Method: A hospital-based retrospective study of clinical records of glaucoma patients from January 2014 to December 2018. The study involved collating demographic information of patients, visual acuities, (VA) intraocular pressure, (IOP), cup-to-disc ratios, (CDRs), average retinal nerve fibers thickness, (RNFL), cup volume, cup-to-disc area, vertical cup-to-disc ratio, (VCDR), rim area, disc area, glaucoma hemifield test, visual field indices and the management of glaucoma. Results: Nine thousand one hundred and eighty-five (9,185) folders were retrieved. Out of these, 432 (4.7%) qualified for the study and were analyzed. There were 267 (61.8%) males and 165 (38.2%) females. The mean age (± Standard deviation, SD) of the patients was 62.66 ± 15.94 years, (range 10 - 110 years). The means visual acuity (VA): OD =1.30 ± 1.06 Logarithm of the Minimum Angle of Resolution, (logMAR), OS = 1.33 ± 1.06 logMAR; IOP: OD = 29.51 ± 12.89 mmHg, OS: 29.17 ± 12.59 mmHg; CDRs: OD = 0.91 ± 0.14 D, OS = 0.92 ± 0.14 D; and the average RNFL thickness was 72.76 ± 18.26 µm and 71.24 ± 23.17 µm in the right and left eye respectively. The mainstay of treatment was medication only. Conclusion: There were more males than females receiving glaucoma care at the tertiary level. Glaucoma cases included juveniles but the mean age was mostly the elderly. It was characterized by high IOPs, large CDRs, and thin RNFL suggestive of late presentation.


Assuntos
Glaucoma/diagnóstico , Glaucoma/epidemiologia , Encaminhamento e Consulta/estatística & dados numéricos , Adolescente , Adulto , Grupo com Ancestrais do Continente Africano , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Glaucoma/terapia , Glaucoma de Ângulo Aberto/epidemiologia , Humanos , Pressão Intraocular/fisiologia , Masculino , Pessoa de Meia-Idade , Fibras Nervosas/patologia , Retina/anatomia & histologia , Estudos Retrospectivos , Fatores Socioeconômicos , Campos Visuais/fisiologia , Adulto Jovem , Zimbábue/epidemiologia
3.
J Vet Sci ; 22(5): e65, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34423602

RESUMO

BACKGROUND: To assess the normal retina of the pigeon eye using spectral domain optical coherence tomography (SD-OCT) and establish a normative reference. METHODS: Twelve eyes of six ophthalmologically normal pigeons (Columba livia) were included. SD-OCT images were taken with dilated pupils under sedation. Four meridians, including the fovea, optic disc, red field, and yellow field, were obtained in each eye. The layers, including full thickness (FT), ganglion cell complex (GCC), thickness from the retinal pigmented epithelium to the outer nuclear layer (RPE-ONL), and from the retinal pigmented epithelium to the inner nuclear layer (RPE-INL), were manually measured. RESULTS: The average FT values were significantly different among the four meridians (p < 0.05), with the optic disc meridian being the thickest (294.0 ± 13.9 µm). The average GCC was thickest in the optic disc (105.3 ± 27.1 µm) and thinnest in the fovea meridian (42.8 ± 15.3 µm). The average RPE-INL of the fovea meridian (165.5 ± 18.3 µm) was significantly thicker than that of the other meridians (p < 0.05). The average RPE-ONL of the fovea, optic disc, yellow field, and red field were 91.2 ± 5.2 µm, 87.7 ± 5.3 µm, 87.6 ± 6.5 µm, and 91.4 ± 3.9 µm, respectively. RPE-INL and RPE-ONL thickness of the red field meridian did not change significantly with measurement location (p > 0.05). CONCLUSIONS: Measured data could be used as normative references for diagnosing pigeon retinopathies and further research on avian fundus structure.


Assuntos
Columbidae/anatomia & histologia , Retina/anatomia & histologia , Tomografia de Coerência Óptica/veterinária , Animais , Columbidae/fisiologia , Valores de Referência , Retina/fisiologia , Epitélio Pigmentado da Retina/anatomia & histologia , Epitélio Pigmentado da Retina/fisiologia
4.
Curr Opin Ophthalmol ; 32(5): 489-493, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34231528

RESUMO

PURPOSE OF REVIEW: Classically, ROP has been considered a neonatal disease only; however, pediatric ophthalmologists and retinal specialists worldwide are recently facing a new paradigm shift. retinopathy of prematurity (ROP) is now considered a lifelong disease that extends well into adulthood. The purpose of this review is to describe the adult ROP anatomy and discuss the late sequelae and management of this disease. RECENT FINDINGS: Neonatal ROP treatments affect both anterior and posterior segment anatomy. Anterior segment changes secondary to inflammation and posterior ciliary nerve ablation range from acute to chronic pathology, including cataract, secondary glaucoma, and corneal decompensation. Persistent avascular retina can be present in previously treated Type 1 ROP eyes after anti-vascular endothelial growth factor or in 'normal' untreated eyes that did not previously meet Type 1 ROP criteria. Persistent avascular retina is associated with lattice-like changes, retinal tears, and detachments. The location and extent of the ridge, posterior hyaloidal contraction and adhesion, and persistent avascular retina all contribute to a spectrum of findings ranging from reactivation of neovascularization, tractional, rhegmatogenous, or exudative detachments. SUMMARY: Understanding Adult ROP anatomy is critical in identification of retinal pathology and treatment choice. ROP patients require lifelong monitoring.


Assuntos
Retina/patologia , Retinopatia da Prematuridade , Adulto , Progressão da Doença , Humanos , Lactente , Recém-Nascido , Fotocoagulação a Laser/efeitos adversos , Retina/anatomia & histologia , Retina/efeitos dos fármacos , Retina/cirurgia , Retinopatia da Prematuridade/diagnóstico , Retinopatia da Prematuridade/patologia , Retinopatia da Prematuridade/terapia
5.
J Sci Med Sport ; 24(11): 1100-1104, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33824079

RESUMO

OBJECTIVES: To collect information about the retinal blood flow variations and other choroidal and retinal parameters during a prolonged effort such as marathon running. DESIGN: Non-randomized prospective cohort study. METHODS: Patients were recruited through an information campaign at the Rothschild Foundation Hospital (Paris, France). A first visit (V1) was planned in the month before the marathon. All participants underwent blood pressure measurement, fundus photography, spectral domain-optical coherence tomography (SD-OCT) and OCT-angiography (OCT-A). A second visit (V2) was scheduled within one hour of crossing the finish line. The same tests were repeated, using the same equipment. RESULTS: Of the 31 runners who were included, 29 finished the marathon and attended V2. At baseline, various ophthalmological abnormalities were found in 45.2% of the 58 eyes, among which almost a third concerned the optic nerve and a quarter the pachychoroid spectrum. A significant decrease in retinal vascular plexus density was found between V1 and V2 (p<0.01). While median macular and retinal nerve fiber layer (RNFL) thicknesses significantly increased after the marathon (p<0.01), median choroidal thickness significantly decreased (p<0.01). Both systolic and diastolic blood pressures significantly decreased (p<0.01 and p=0.021 respectively). CONCLUSIONS: Prolonged physical effort impacts the structure and vascularization of the retina and the choroid. Hypoxia and dehydration due to such an effort may induce a low ocular blood flow rate resulting in a choroidal thinning, contrasting with a transient subclinical ischemic edema of the inner retina and optic nerve head. CLINICAL TRIAL REGISTRATION NUMBER: NCT03864380.


Assuntos
Corioide/irrigação sanguínea , Corrida de Maratona/fisiologia , Fluxo Sanguíneo Regional , Retina/fisiologia , Corioide/diagnóstico por imagem , Desidratação/fisiopatologia , Humanos , Fibras Nervosas/fisiologia , Projetos Piloto , Estudos Prospectivos , Sistema Renina-Angiotensina/fisiologia , Retina/anatomia & histologia , Retina/diagnóstico por imagem , Tomografia de Coerência Óptica
6.
Exp Eye Res ; 203: 108394, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33310058

RESUMO

Micro-CT visualization allows reconstruction of eye structures with the resolution of light microscopy and estimation of tissue densities. Moreover, this method excludes damaging procedures and allows further histological staining due to the similar steps in the beginning. We have shown the feasibility of the lab-based micro-CT machine usage for visualization of clinically important compartments of human eye such as trabecular outflow pathway, retina, iris and ciliary body after pre-treatment with iodine in ethanol. We also identified the challenges of applying this contrasting technique to lens, cornea, and retina and proposed alternative staining methods for these tissues. Thereby this work provides a starting point for other studies for imaging of human eyes in normal and pathological conditions using lab-based micro-CT systems.


Assuntos
Enucleação Ocular , Olho/anatomia & histologia , Olho/diagnóstico por imagem , Microtomografia por Raio-X , Câmara Anterior/anatomia & histologia , Câmara Anterior/diagnóstico por imagem , Segmento Anterior do Olho/anatomia & histologia , Segmento Anterior do Olho/diagnóstico por imagem , Estudos de Viabilidade , Humanos , Imageamento Tridimensional , Cristalino/anatomia & histologia , Cristalino/diagnóstico por imagem , Retina/anatomia & histologia , Retina/diagnóstico por imagem
7.
Int J Mol Sci ; 21(21)2020 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-33182490

RESUMO

The retinal pigment epithelium (RPE) is located between the neuroretina and the choroid, and plays a critical role in vision. RPE cells internalise outer segments (OS) from overlying photoreceptors in the daily photoreceptor renewal. Changes to RPE structure are linked with age and retinopathy, which has been described in the past by conventional 2D electron microscopy. We used serial block face scanning electron microscopy (SBF-SEM) to reconstruct RPE cells from the central mouse retina. Three-dimensional-reconstructed OS revealed the RPE to support large numbers of photoreceptors (90-216 per RPE cell). Larger bi-nucleate RPE maintained more photoreceptors, although their cytoplasmic volume was comparable to smaller mono-nucleate RPE supporting fewer photoreceptors. Scrutiny of RPE microvilli and interdigitating OS revealed the angle and surface area of contact between RPE and photoreceptors. Bi-nucleate RPE contained more mitochondria compared to mono-nucleate RPE. Furthermore, bi-nucleate cells contained larger sub-RPE spaces, supporting a likely association with disease. Use of perfusion-fixed tissues ensured the highest possible standard of preservation, providing novel insights into the 3D RPE architecture and changes linked with retinopathy. This study serves as a benchmark for comparing retinal tissues from donor eyes with age-related macular degeneration (AMD) and other retinopathies.


Assuntos
Células Epiteliais/citologia , Retina/anatomia & histologia , Epitélio Pigmentado da Retina/anatomia & histologia , Animais , Corioide/citologia , Corioide/metabolismo , Células Epiteliais/metabolismo , Feminino , Angiofluoresceinografia/métodos , Degeneração Macular/metabolismo , Degeneração Macular/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Mitocôndrias/fisiologia , Retina/citologia , Retina/metabolismo , Células Fotorreceptoras Retinianas Cones/citologia , Células Fotorreceptoras Retinianas Cones/metabolismo , Epitélio Pigmentado da Retina/citologia , Epitélio Pigmentado da Retina/metabolismo , Pigmentos da Retina/metabolismo , Tomografia de Coerência Óptica/métodos
8.
PLoS One ; 15(10): e0239719, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33002017

RESUMO

In the present study, we investigated the topographical distribution of ganglion cells and displaced amacrine cells in the retina of the collared peccary (Pecari tajacu), a diurnal neotropical mammal of the suborder Suina (Order Artiodactyla) widely distributed across central and mainly South America. Retinas were prepared and processed following the Nissl staining method. The number and distribution of retinal ganglion cells and displaced amacrine cells were determined in six flat-mounted retinas from three animals. The average density of ganglion cells was 351.822 ± 31.434 GC/mm2. The peccary shows a well-developed visual streak. The average peak density was 6,767 GC/mm2 and located within the visual range and displaced temporally as an area temporalis. Displaced amacrine cells have an average density of 300 DAC/mm2, but the density was not homogeneous along the retina, closer to the center of the retina the number of cells decreases and when approaching the periphery the density increases, in addition, amacrine cells do not form retinal specialization like ganglion cells. Outside the area temporalis, amacrine cells reach up to 80% in the ganglion cell layer. However, in the region of the area temporalis, the proportion of amacrine cells drops to 32%. Thus, three retinal specializations were found in peccary's retina by ganglion cells: visual streak, area temporalis and dorsotemporal extension. The topography of the ganglion cells layer in the retina of the peccary resembles other species of Order Artiodactyla already described and is directly related to its evolutionary history and ecology of the species.


Assuntos
Células Amácrinas/ultraestrutura , Artiodáctilos/anatomia & histologia , Retina/anatomia & histologia , Células Ganglionares da Retina/ultraestrutura , Animais , Contagem de Células , Masculino
9.
Artigo em Inglês | MEDLINE | ID: mdl-32887214

RESUMO

In early and intermediate age related macular degeneration (ARMD), visual acuity alone has failed to explain the complete variation of vision. The aim of the present study was to determine correlation between different visual functions and retinal morphology in eyes with early and intermediate ARMD. In this single center cross sectional study, patients diagnosed as early or intermediate ARMD in at least one eye were recruited. Visual functions measured were best- corrected distance visual acuity (DVA), near vision acuity (NVA), reading speed (RS), and contrast sensitivity (CS). Parameters such as thickness (RT) and volume (RV) of the retina, outer retinal layer thickness (ORLT) and volume (ORLV), outer nuclear layer thickness (ONLT) and volume (ONLV), retinal pigment epithelium layer-Bruch's membrane complex thickness (RPET) and volume (RPEV) were assessed employing semi-auto segmentation method of Spectralis optical coherence tomography (OCT). Twenty-six eyes were evaluated. DVA, CS, and RS showed significantly good correlation with RPET, ONLT, and ONLV, whereas NVA showed good correlation with ONLV and RPET. The present study concluded that RS, CS, NVA, and DVA represent the morphological alteration in early stages and should be tested in clinical settings. ONLT, ONLV, and RPET morphological parameters can be employed as important biomarkers in diagnosis of early to intermediate ARMD.


Assuntos
Degeneração Macular , Retina , Acuidade Visual , Idoso , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Retina/anatomia & histologia , Tomografia de Coerência Óptica
10.
J Neurosci ; 40(42): 8055-8069, 2020 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-32948676

RESUMO

Members of the arrestin superfamily have great propensity of self-association, but the physiological significance of this phenomenon is unclear. To determine the biological role of visual arrestin-1 oligomerization in rod photoreceptors, we expressed mutant arrestin-1 with severely impaired self-association in mouse rods and analyzed mice of both sexes. We show that the oligomerization-deficient mutant is capable of quenching rhodopsin signaling normally, as judged by electroretinography and single-cell recording. Like wild type, mutant arrestin-1 is largely excluded from the outer segments in the dark, proving that the normal intracellular localization is not due the size exclusion of arrestin-1 oligomers. In contrast to wild type, supraphysiological expression of the mutant causes shortening of the outer segments and photoreceptor death. Thus, oligomerization reduces the cytotoxicity of arrestin-1 monomer, ensuring long-term photoreceptor survival.SIGNIFICANCE STATEMENT Visual arrestin-1 forms dimers and tetramers. The biological role of its oligomerization is unclear. To test the role of arrestin-1 self-association, we expressed oligomerization-deficient mutant in arrestin-1 knock-out mice. The mutant quenches light-induced rhodopsin signaling like wild type, demonstrating that in vivo monomeric arrestin-1 is necessary and sufficient for this function. In rods, arrestin-1 moves from the inner segments and cell bodies in the dark to the outer segments in the light. Nonoligomerizing mutant undergoes the same translocation, demonstrating that the size of the oligomers is not the reason for arrestin-1 exclusion from the outer segments in the dark. High expression of oligomerization-deficient arrestin-1 resulted in rod death. Thus, oligomerization reduces the cytotoxicity of high levels of arrestin-1 monomer.


Assuntos
Arrestinas/metabolismo , Arrestinas/fisiologia , Adaptação Ocular , Animais , Arrestinas/genética , Sobrevivência Celular , Eletrorretinografia , Feminino , Transdução de Sinal Luminoso , Masculino , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Mutação/genética , Retina/anatomia & histologia , Retina/crescimento & desenvolvimento , Células Fotorreceptoras Retinianas Bastonetes/metabolismo , Rodopsina/fisiologia
11.
Middle East Afr J Ophthalmol ; 27(2): 100-104, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32874042

RESUMO

PURPOSE: The aim of this study is to evaluate the short anatomical and visual outcomes of scleral buckling surgery in relation to the pattern of presentation of rhegmatogenous retinal detachment (RRD) in the presence of different situations and risk factors. METHODS: A total of 206 eyes of 203 patients who underwent scleral buckling surgery for RRD were evaluated in this retrospective study. Information retrieved included patient demographics, duration of symptoms, and presenting vision, lens status, site of a retinal break, extent of retinal detachment, the involvement of the fellow eye, macular involvement, presence of lattice degeneration, and associated refractive errors. Postoperative retinal reattachment, postoperative visual acuity, the need for further surgical intervention, intraoperative, and postoperative complications were also evaluated. Proportions and percentages were used to analyze data. RESULTS: Primary anatomical reattachment was seen in 172 eyes (83.5%) after the complete resolution of the tamponade used. The mean best-corrected visual acuity improved from 2.81 logarithms of the minimum angle of resolution (LogMar) preoperatively to 1.21 LogMar postoperatively, the most important factors that appeared statistically significantly affecting the anatomic and visual outcome were the duration of macular detachment (P = 0.036), the status of the lens; phakic eyes gave better visual outcome than aphakic and pseudophakic eyes (P < 0.05). CONCLUSION: Scleral buckling procedure showed high structural and visual success rates, improvement of visual acuity was found to correlate well with the shorter duration of macular detachment and pseudophakic eyes. We believe that scleral buckling, when done appropriately in the appropriate cases, gives the maximum visual outcome with the least cost and need for consecutive procedures.


Assuntos
Retina/anatomia & histologia , Descolamento Retiniano/cirurgia , Recurvamento da Esclera/métodos , Acuidade Visual/fisiologia , Adulto , Idoso , Tamponamento Interno , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Descolamento Retiniano/fisiopatologia , Estudos Retrospectivos , Resultado do Tratamento , Vitrectomia/métodos
12.
Vet Ophthalmol ; 23(5): 863-871, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32741065

RESUMO

OBJECTIVE: To provide images of the anterior and posterior structures of the gecko eye using spectral domain optical coherence tomography (SD-OCT). ANIMALS AND PROCEDURES: Eight ophthalmologically normal Tokay geckos (Gekko gecko) were used. The nose-cloaca distance and body weight were measured for each gecko. Tomographic images were obtained using SD-OCT without the use of anesthetic or mydriatic agents. The central corneal thickness (CCT), the anterior chamber depth (ACD), and the length of the conus papillaris (CP) were manually measured using OCT images. The thickness of the retinal nerve fiber layer (RNFL) around the CP and the retinal thickness in all four quadrants (superior, nasal, inferior, and temporal areas) were automatically measured using the OCT software program. RESULTS: The mean values of the nose-cloaca distance and body weight were 13.8 ± 0.9 cm and 41.3 ± 9.0 g, respectively. The mean values of CCT, ACD, and CP length were 177.6 ± 20.9 µm, 1205.0 ± 79.9 µm, and 1546.4 ± 208.8 µm, respectively. The mean value of RNFL thickness was 52.0 ± 8.2 µm, and the superior region was the thickest. The mean value of total retinal thickness was 202.5 ± 9.4 µm, and the temporal region was the thickest. CONCLUSIONS: Tomographic images of the anterior and posterior segments of the living gecko eye could be obtained using the OCT unit. Multiple retinal layers and anatomical features of the CP were identified.


Assuntos
Lagartos/anatomia & histologia , Retina/anatomia & histologia , Animais , Valores de Referência , Tomografia de Coerência Óptica/veterinária
13.
Folia Med (Plovdiv) ; 62(2): 338-344, 2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32666742

RESUMO

AIM: To measure the macular thickness, macular volume and peripapillary retinal nerve fiber layer (RNFL) in healthy Caucasian chil-dren using spectral domain optical coherence tomography (SDOCT) and analyze the correlation of these values with age, refraction, and biometric measurements. MATERIALS AND METHODS: In this cross-sectional study, we recruited 270 healthy children (150 female and 120 male) aged 6 to 17 years with no ocular abnormalities. All children underwent a detailed eye examination. The measurements were obtained using a SDOCT device (SOCT Copernicus REVO). Main outcome measures were macular thickness, macular volume and RNFL thickness. Their correlations with age, refractive error, anterior chamber depth (ACD) and axial length (AL) was analyzed. Right eyes of all subjects were selected for analysis. RESULTS: In this study group (mean age 10.70±2.82 years), the average peripapillary RNFL thickness was 117.11±9.15 µm, the central macular thickness was 232.10±15.81 µm, the average macular thickness was 286.70±9.82 µm, and the average macular volume was 8.01±0.28 mm³. The average values for the biometric data were: axial length - 23.16±0.94 mm, anterior chamber depth - 3.64±0.26 mm, the spherical equivalent (SE) value - +0.81±0.58 diopter. Central macular thickness, inner macular thickness (superior, inferior, nasal, temporal quadrants) values, total macular thickness and macular volume were significantly higher in males than in females. We found a positive correlation between central macular thickness, inner nasal macular thickness, outer inferior macular thickness values, and age. Also, we found a significant correlation between the average macular thickness values and the average macular volume values (p<0.0001). RNFL measurements did not correlate with age (p=0.199). Almost all macular parameters were consistently positively cor-related with SE. A significant correlation was also found between the central macular thickness, inner inferior macular thickness, inner nasal macular thickness and the ACD. We found a significant correlation between the average macular thickness, macular volume, inner superior macular thickness, outer macular thickness (superior, inferior, nasal, temporal quadrants) values and the AL. CONCLUSION: This study found normal reference ranges for RNFL and macular parameters measured by SOCT Copernicus REVO in healthy Caucasian children aged 6-17 years. This normative values could be very useful in early diagnosing and monitoring of optic neuropathy, glaucoma and macular diseases in childhood.


Assuntos
Axônios , Macula Lutea/diagnóstico por imagem , Fibras Nervosas Amielínicas , Células Ganglionares da Retina , Tomografia de Coerência Óptica , Adolescente , Criança , Feminino , Humanos , Macula Lutea/anatomia & histologia , Masculino , Tamanho do Órgão , Valores de Referência , Retina/anatomia & histologia , Retina/diagnóstico por imagem
14.
Med Sci (Paris) ; 36(6-7): 594-599, 2020.
Artigo em Francês | MEDLINE | ID: mdl-32614310

RESUMO

The neuroretina is a functional unit of the central nervous system that converts a light signal into a nerve impulse. Of neuroectodermal origin, derived from the diencephalon, the neuroretina is a layered tissue composed of six types of neuronal cells (two types of photoreceptors: cones and rods, horizontal, bipolar, amacrine and ganglion cells) and three types of glial cells (Müller glial cells, astrocytes and microglial cells). The neuroretina lays on the retinal pigmentary epithelium, that together form the retina. The existence of the internal and external blood-retinal barriers and intra-retinal junctions reflects the fineness of regulation of the retinal exchanges with the circulation and within the retina itself. The central zone of the human retina, which is highly specialized for visual acuity, has anatomical specificities. Recent imaging methods make it possible now to enrich our knowledge of the anatomical and functional characteristics of the retina, which are still imperfectly described.


Assuntos
Retina/anatomia & histologia , Animais , Corioide/irrigação sanguínea , Corioide/citologia , Corioide/fisiologia , Humanos , Neuroglia/citologia , Neuroglia/fisiologia , Retina/citologia , Retina/fisiologia , Retina/ultraestrutura , Células Fotorreceptoras Retinianas Cones/citologia , Células Fotorreceptoras Retinianas Cones/fisiologia , Epitélio Pigmentado da Retina/irrigação sanguínea , Epitélio Pigmentado da Retina/citologia , Epitélio Pigmentado da Retina/fisiologia , Células Fotorreceptoras Retinianas Bastonetes/citologia , Células Fotorreceptoras Retinianas Bastonetes/fisiologia , Vasos Retinianos/citologia , Vasos Retinianos/fisiologia
15.
Cutan Ocul Toxicol ; 39(3): 233-236, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32543917

RESUMO

PURPOSE: To investigate the impact of oral isotretinoin therapy in choroidal thickness, central macular thickness (CMT), and retinal nerve fibre layer (RNFL) thickness using optical coherence tomography (OCT). PATIENTS AND METHODS: Choroidal thicknesses, CMT, and RNFL thickness of 64 eyes were evaluated at baseline and the end of the third month of isotretinoin therapy by spectral-domain OCT. For assessment of choroidal thickness, OCT measurements were obtained at the fovea with 6 additional measurements at adjacent locations (at 500-1000-1500 µm temporal to the fovea and 500-1000-1500 µm nasal to the fovea). RESULTS: There was not a statistically significant difference between the baseline and third-month follow-up measurements of choroidal thicknesses at seven distinct locations (p > 0.05). Similarly, RNFL thickness and CMT did not change with a mean dose of 30 (±6) mg per day isotretinoin therapy during follow-up (101.82 vs 102.24, p = 0.079; 217.77 vs 217.25, p = 0.731, respectively). CONCLUSION: After the use of oral isotretinoin for 3 months, no significant side effects have been observed in choroidal thickness, CMT, and RNFL thickness by OCT.


Assuntos
Corioide/efeitos dos fármacos , Fármacos Dermatológicos/uso terapêutico , Isotretinoína/uso terapêutico , Fibras Nervosas/efeitos dos fármacos , Retina/efeitos dos fármacos , Acne Vulgar/diagnóstico por imagem , Acne Vulgar/tratamento farmacológico , Administração Oral , Adolescente , Adulto , Corioide/anatomia & histologia , Corioide/diagnóstico por imagem , Feminino , Humanos , Masculino , Retina/anatomia & histologia , Retina/diagnóstico por imagem , Tomografia de Coerência Óptica , Adulto Jovem
16.
Appl Opt ; 59(13): D111-D117, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32400631

RESUMO

An optical fiber-based supercontinuum setup and a custom-made spectrophotometer that can measure spectra from 1100 to 2300 nm, are used to describe attenuation properties from different ex vivo rat tissues. Our method is able to differentiate between scattering and absorption coefficients in biological tissues. Theoretical assumptions combined with experimental measurements demonstrate that, in this infrared range, tissue attenuation and absorption can be accurately measured, and scattering can be described as the difference between both magnitudes. Attenuation, absorption, and scattering spectral coefficients of heart, brain, spleen, retina, and kidney are given by applying these theoretical and experimental methods. Light through these tissues is affected by high scattering, resulting in multiple absorption events, and longer wavelengths should be used to obtain lower attenuation values. It can be observed that the absorption coefficient has a similar behavior in the samples under study, with two main zones of absorption due to the water absorption bands at 1450 and 1950 nm, and with different absolute absorption values depending on the constituents of each tissue. The scattering coefficient can be determined, showing slight differences between retina and brain samples, and among heart, spleen and kidney tissues.


Assuntos
Encéfalo/diagnóstico por imagem , Coração/diagnóstico por imagem , Rim/diagnóstico por imagem , Imagem Óptica/métodos , Retina/diagnóstico por imagem , Baço/diagnóstico por imagem , Animais , Encéfalo/anatomia & histologia , Coração/anatomia & histologia , Técnicas In Vitro , Rim/anatomia & histologia , Modelos Biológicos , Modelos Teóricos , Óptica e Fotônica , Ratos Sprague-Dawley , Retina/anatomia & histologia , Espalhamento de Radiação , Espectroscopia de Luz Próxima ao Infravermelho , Baço/anatomia & histologia
17.
Medicina (Kaunas) ; 56(5)2020 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-32429361

RESUMO

Background and Objectives: Despite the growing number of new research publications, normative references for children's optical coherence tomography (OCT) parameters are still not completed. We chose to explore this topic because of the lack of normative parameters that is due to an improvement in different technologies and instruments. Our aim was to determine referential rates of retinal nerve fiber layer (RNFL) thickness and flow deficits (FD%) in the macular choriocapillaris (CC) in normal eyes of ophthalmologically healthy children. Materials and Methods: Ophthalmologically healthy 8- to 14-year-old individuals participated (n = 75) in this study. OCT images were taken using an swept-source-OCT (SS-OCT) instrument (DRI-OCT Triton, Topcon, Tokyo, Japan). The early treatment diabetic retinopathy study (EDTRS) grid (6 × 6 mm) divided the RNFL into the thickness maps. The FD% values of the CC were calculated on the 3 × 3-mm scans in a 1-mm circle (C1), 1.5-mm rim (R1.5), and the entire 2.5-mm circle (C2.5), and on the 6 x 6-mm scans in a 1-mm circle (C1), 1.5-mm rim (R1.5), the entire 2.5-mm circle (C2.5), 2.5-mm rim (R2.5), and 5-mm circle (C5). Results: Both scan quantifications of FD% in the C1, C2.5, and R1.5 sectors were similar, but the 6 × 6-mm scan measurements were statistically significantly smaller than the 3 × 3-mm ones. Significant moderate correlations were found between axial length (AxL) and FD% in the 6 × 6-mm scans, namely C1 (r = -0.347, p = 0.002), C2.5 (r = -0.337, p = 0.003), R1.5 (r = -0.328, p = 0.004), R2.5 (r = -0.306, p = 0.008), and C5 (r = -0.314, p = 0.006). Conclusions: The thinnest RNFL layers were on the temporal and nasal sides. FD% values in the C1, C2.5, and R1.5 sectors were similar between the 3 × 3-mm and 6 × 6-mm scans. The negative moderate correlations between AxL and FD% were found in all C1, C2.5, C5, R1.5, and R2.5 sectors of the 6 × 6-mm scans. Further prospective studies are needed to determine more accurate normative references for children's OCT parameters.


Assuntos
Corioide/anatomia & histologia , Retina/anatomia & histologia , Tomografia de Coerência Óptica/métodos , Angiografia , Criança , Corioide/diagnóstico por imagem , Estudos Transversais , Feminino , Humanos , Masculino , Disco Óptico/anatomia & histologia , Disco Óptico/diagnóstico por imagem , Estudos Prospectivos , Valores de Referência , Retina/diagnóstico por imagem , Células Ganglionares da Retina/fisiologia
18.
Invest Ophthalmol Vis Sci ; 61(5): 44, 2020 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-32446249

RESUMO

Purpose: To investigate segmented macular layer volumes from a healthy adult twin cohort (TwinsUK), exploring changes with age and heritability. Methods: Macular spectral domain optical coherence tomography images were acquired from monozygotic (MZ) and dizygotic (DZ) twins in a cross-sectional study. The following layer volumes were derived for circles of 3 and 6 mm diameter around the foveal center, using automated segmentation software: retinal nerve fiber layer (RNFL), ganglion cell-inner plexiform layer (GCIPL), inner nuclear layer (INL), outer plexiform layer (OPL), outer nuclear layer (ONL), photoreceptors (PR), retinal pigment epithelium (RPE), and total retinal volume (TRV). Correlation coefficients (intereye; age; intrapair for MZ and DZ pairs) were quantified; heritability was estimated using structural equation modeling. Results: Scans from 184 participants were included. Intereye correlation was highest for TRV and GCIPL. Negative correlations with age (for 3- or 6-mm areas, or both) were observed for TRV, RNFL, GCIPL, and INL. Positive correlations were observed for PR, RPE, and OPL. For all layers, intrapair correlation was greater for MZ than DZ pairs. Heritability estimates were highest (>80%) for TRV and GCIPL volume, and lowest for RPE volume. Conclusions: Although TRV was negatively correlated with age, all layers did not show negative correlation. Some inner layers thinned with age, whereas some outer volumes increased (not the ONL). Reduced RPE phagocytic function with age and remodeling in the OPL could be contributing factors. Heritability estimates were highest for inner retinal layers (particularly GCIPL), and lowest for RPE volume.


Assuntos
Retina/anatomia & histologia , Retina/diagnóstico por imagem , Tomografia de Coerência Óptica , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Correlação de Dados , Estudos Transversais , Feminino , Humanos , Padrões de Herança , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão
19.
Biomed Res Int ; 2020: 7361492, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32280700

RESUMO

Purpose: To evaluate the influence of systemic and ocular factors on the foveal avascular zone (FAZ) area in young Chinese subjects' healthy eyes. Methods: The current observational, cross-sectional study included 344 eyes from 172 healthy individuals (103 women, 69 men). Optical coherence tomography angiography realized with the split-spectrum amplitude-decorrelation angiography (SSADA) algorithm was used to assess the area of superficial FAZ. To determine the related factors and to reveal their potential correlations with the FAZ area, comprehensive examinations including both systemic and ocular ones were executed. Systemic examination involved factors including age, gender, and body mass index, while ocular examination involved factors including BCVA, refractive error, intraocular pressure, axial length (AL), anterior chamber depth, and central corneal thickness. Especially for fundus examination, central macular thickness (CMT), retinal volume, mean retinal thickness, macular blood flow area/vessel density in the superficial retinal layer (SRL) and deep retinal layer (DRL), mean retinal nerve fiber layer (RNFL) thickness, ganglion cell layer (GCL) thickness, C/D rate, rim area, and subfoveal choroid thickness were assessed, using mixed-effects regression models to appropriately account for intereye correlation. Subgroup analyses were performed based on gender and high myopia categories. Results: The mean FAZ area was 0.30 ± 0.11 mm2 and varied significantly across gender (P = 0.0024). AL, CMT, and RNFL thickness were found significantly correlated with the FAZ area in the univariate regression analysis (AL, P = 0.0005; CMT, P < 0.0001; and RNFL thickness, P = 0.0461). According to the multivariate results, CMT and macular blood flow in SRL were negatively correlated with FAZ (CMT: P < 0.0001; macular blood flow in SRL: P = 0.00223). Mean retinal thickness, mean GCL thickness, and macular blood flow in DRL were positively correlated with FAZ (mean retinal thickness: P = 0.0005; mean GCL thickness: P < 0.0001; and macular blood flow in DRL: P = 0.0099). Correlation results among these filtered factors and FAZ were more pronounced in non-high-myopic eyes than in high-myopic eyes and had a significant difference when data of male and female subjects were processed separately from each other. Conclusion: The present cross-sectional study performed comprehensive systemic and ocular examinations in young Chinese adults and filtered factors affecting FAZ. We indicated that among all the assessed candidate factors, gender, AL, retinal thickness, macular blood flow, RNFL, and GCL thickness affected the FAZ area most significantly. Such findings would facilitate future research concerning the role of FAZ variation in fundus diseases.


Assuntos
Macula Lutea/diagnóstico por imagem , Macula Lutea/patologia , Adulto , Grupo com Ancestrais do Continente Asiático , Estudos Transversais , Feminino , Angiofluoresceinografia/métodos , Fóvea Central/irrigação sanguínea , Fundo de Olho , Humanos , Macula Lutea/irrigação sanguínea , Masculino , Miopia , Retina/anatomia & histologia , Retina/diagnóstico por imagem , Vasos Retinianos , Tomografia de Coerência Óptica/métodos
20.
Sci Rep ; 10(1): 6142, 2020 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-32273540

RESUMO

This study aimed to evaluate the association between optical coherence tomography (OCT)-measured retinal layer thickness parameters with clinical and patient-centred visual outcomes in healthy eyes. Participants aged 40 and above were recruited from the Singapore Epidemiology of Eye Diseases Study, a multi-ethnic population-based study. Average macular, ganglion cell-inner plexiform layer (GCIPL), and outer retinal thickness parameters were obtained using the Cirrus High Definition-OCT. Measurements of best-corrected visual acuity (BCVA) and 11-item visual functioning questionnaire (VF-11) were performed. Associations between macular thickness parameters, with BCVA and Rasch-transformed VF-11 scores (in logits) were assessed using multivariable linear regression models with generalized estimating equations, adjusted for relevant confounders. 4,540 subjects (7,744 eyes) with a mean age of 58.8 ± 8.6 years were included. The mean BCVA (LogMAR) was 0.10 ± 0.11 and mean VF-11 score was 5.20 ± 1.29. In multivariable regression analysis, thicker macula (per 20 µm; ß = -0.009) and GCIPL (per 20 µm; ß = -0.031) were associated with better BCVA (all p ≤ 0.001), while thicker macula (per 20 µm; ß = 0.04) and GCIPL (per 20 µm, ß = 0.05) were significantly associated with higher VF-11 scores (all p < 0.05). In conclusion, among healthy Asian eyes, thicker macula and GCIPL were associated with better vision and self-reported visual functioning. These findings provide further understanding on the potential influence of macular thickness on visual function.


Assuntos
Macula Lutea/anatomia & histologia , Visão Ocular , Feminino , Humanos , Macula Lutea/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Retina/anatomia & histologia , Retina/diagnóstico por imagem , Células Ganglionares da Retina/ultraestrutura , Singapura , Tomografia de Coerência Óptica , Acuidade Visual
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