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1.
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
2.
PLoS One ; 15(3): e0229142, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32134934

RESUMO

Migratory birds can detect the direction of the Earth's magnetic field using the magnetic compass sense. However, the sensory basis of the magnetic compass still remains a puzzle. A large body of indirect evidence suggests that magnetic compass in birds is localized in the retina. To confirm this point, an evidence of visual signals modulation by magnetic field (MF) should be obtained. In a previous study we showed that MF inclination impacts the amplitude of ex vivo electroretinogram (ERG) recorded from isolated pigeon retina. Here we present the results of an analysis of putative MF effect on one component of ERG, the photoreceptor's response, isolated from the total ERG by adding sodium aspartate and barium chloride to the perfusion solution. Photoresponses were recorded from isolated retinae of domestic pigeons Columba livia. The retinal samples were placed in MF that was modulated by three pairs of orthogonal Helmholtz coils. Light stimuli (blue and red) were applied under two inclinations of MF, 0° and 90°. In all the experiments, preparations from two parts of retina were used, red field (with dominant red-sensitive cones) and yellow field (with relatively uniform distribution of cone color types). In contrast to the whole retinal ERG, we did not observe any effect of MF inclination on either amplitude or kinetics of pharmacologically isolated photoreceptor responses to blue or red half-saturating flashes. A possible explanations of these results could be that magnetic compass sense is localized in retinal cells other than photoreceptors, or that photoreceptors do participate in magnetoreception, but require some processing of compass information in other retinal layers, so that only whole retina signal can reflect the response to changing MF.


Assuntos
Migração Animal/fisiologia , Columbidae/anatomia & histologia , Campos Magnéticos , Orientação Espacial/fisiologia , Células Fotorreceptoras de Vertebrados/fisiologia , Retina/anatomia & histologia , Resposta Táctica/fisiologia , Animais , Cor , Eletrorretinografia/veterinária , Fundo de Olho , Luz , Magnetismo , Estimulação Luminosa , Células Fotorreceptoras de Vertebrados/citologia , Retina/citologia , Retina/diagnóstico por imagem , Células Fotorreceptoras Retinianas Cones/citologia , Células Fotorreceptoras Retinianas Cones/fisiologia
3.
Invest Ophthalmol Vis Sci ; 61(3): 9, 2020 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-32176260

RESUMO

Purpose: To investigate diurnal variation in the length of mouse rod outer segments in vivo. Methods: The lengths of rod inner and outer segments (RIS, ROS) of dark-adapted albino mice maintained on a 12-hour dark:12-hour light cycle with light onset 7 AM were measured at prescribed times (6:30 AM, 11 AM, 3:30 PM) during the diurnal cycle with optical coherence tomography (OCT), taking advantage of increased visibility, after a brief bleaching exposure, of the bands corresponding to RIS/ROS boundaries and ROS tips (ROST). Results: Deconvolution of OCT depth profiles resolved two backscatter bands located 7.4 ± 0.1 and 10.8 ± 0.2 µm (mean ± SEM) proximal to Bruch's membrane (BrM). These bands were identified with histology as arising from the apical surface of RPE and ROST, respectively. The average length of dark-adapted ROS at 6:30 AM was 17.7 ± 0.8 µm. By 11 AM, the average ROS length had decreased by 10% to 15.9 ± 0.7 µm. After 11 AM, the ROS length increased steadily at an average rate of 0.12 µm/h, returning to baseline length by 23.5 hours in the cycle. Conclusions: The diurnal variation in ROS length measured in these experiments is consistent with prior histological investigations showing that rodent rod discs are phagocytosed by the RPE maximally over several hours around the time of normal light onset. The rate of recovery of ROS to baseline length before normal light onset is consistent with the hypothesis that disc membrane synthesis is fairly constant over the diurnal cycle.


Assuntos
Ritmo Circadiano/fisiologia , Segmento Externo da Célula Bastonete/fisiologia , Albinismo Ocular/patologia , Animais , Lâmina Basilar da Corioide/ultraestrutura , Adaptação à Escuridão/fisiologia , Camundongos Endogâmicos BALB C , Microscopia Confocal , Fagocitose/fisiologia , Retina/anatomia & histologia , Retina/diagnóstico por imagem , Segmento Interno das Células Fotorreceptoras da Retina/fisiologia , Segmento Interno das Células Fotorreceptoras da Retina/ultraestrutura , Segmento Externo da Célula Bastonete/ultraestrutura , Espalhamento de Radiação , Tomografia de Coerência Óptica/métodos
4.
Elife ; 82019 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-31820735

RESUMO

The retina has a very high energy demand but lacks an internal blood supply in most vertebrates. Here we explore the hypothesis that oxygen diffusion limited the evolution of retinal morphology by reconstructing the evolution of retinal thickness and the various mechanisms for retinal oxygen supply, including capillarization and acid-induced haemoglobin oxygen unloading. We show that a common ancestor of bony fishes likely had a thin retina without additional retinal oxygen supply mechanisms and that three different types of retinal capillaries were gained and lost independently multiple times during the radiation of vertebrates, and that these were invariably associated with parallel changes in retinal thickness. Since retinal thickness confers multiple advantages to vision, we propose that insufficient retinal oxygen supply constrained the functional evolution of the eye in early vertebrates, and that recurrent origins of additional retinal oxygen supply mechanisms facilitated the phenotypic evolution of improved functional eye morphology.


Assuntos
Evolução Biológica , Olho/anatomia & histologia , Olho/crescimento & desenvolvimento , Oxigênio/metabolismo , Retina/anatomia & histologia , Retina/metabolismo , Vertebrados , Animais
5.
Opt Express ; 27(26): 38289-38311, 2019 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-31878599

RESUMO

State-of-the-art near-eye displays often compromise on eye box size to maintain a wide field of view, necessitating a means for steering the eye box to maintain alignment with a moving eye. The design space of such pupil-steered systems is not well defined and the implications of imperfect steering on the perceived image are not well understood. To better characterize the pupil steering design space, we introduce a generalized taxonomy of pupil-steered architectures that considers both system and ocular factors that affect steering performance. We also develop an optical model of a generalized pupil-steered system with a wide-field schematic eye to simulate the retinal image. Using this framework, we systematically characterize retinal image quality for different combinations of design parameters. The results of these simulations provide an overview of the pupil steering design space and help determine relevant psychophysical experiments for further evaluation.


Assuntos
Aumento da Imagem , Pupila/fisiologia , Retina/anatomia & histologia , Humanos , Modelos Biológicos , Rotação
6.
Arch. Soc. Esp. Oftalmol ; 94(12): 579-584, dic. 2019. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-190008

RESUMO

OBJETIVO: Describir las características morfométricas y espesor de la capa de fibras nerviosas de la retina (CFNR) en pacientes sanos usando la tomografía de coherencia óptica. MÉTODOS: Estudio transversal y descriptivo. Un total de 184 ojos de 184 personas de etnia mestiza fueron inscritos después de una evaluación oftalmológica completa en el Instituto Nacional de Oftalmología, Lima-Perú. Se midieron los parámetros morfométricos del disco óptico y espesor de la CFNR mediante tomografía de coherencia óptica ZEISS CIRRUS(TM) HD-OCT Modelo 5000 (Carl Zeiss Inc., Dublin, CA, EE.UU). Megalopapila fue definida como: área del disco óptico > 2,5 mm2 y área mayor que la media más 2 desviaciones estándar. RESULTADOS: Se obtuvo un área de disco óptico de 2,21 ± 0,43 mm2, anillo neurorretinal de 1,37 ± 0,25 mm2, excavación de 0,84 ± 0,48 mm2; promedio de ratio excavación/disco de 0,58 ± 0,16, ratio excavación/disco vertical de 0,55 ± 0,15 y un espesor de CFNR 100,30 ± 8,54 μm. La prevalencia de megalopapila fue del 24 y 4%, considerando un área de disco > 2,5 mm2 y 3,07 mm2 respectivamente. Al comparar megalopapilas con discos normales, el área del anillo (p = 0,08) y espesor de CFNR (p = 0,73) no mostraron diferencias estadísticamente significativas. CONCLUSIÓN: El área de disco fue 2,21 ± 0,43 mm2 con un espesor de CFNR 100,30±8,54μm. La prevalencia de megalopapila fue del 24 y 4%, considerando un área de disco>2,5mm2 y 3,07mm2 respectivamente. Las megalopapilas y los discos normales son similares en términos de área del anillo y espesor de CFNR


OBJECTIVE: To describe the morphometric characteristics and thickness of the retinal nerve fibre layer (CFNR) in healthy patients using optical coherence tomography. METHODS: A cross-sectional and descriptive study was conducted on a total of 184 eyes of 184 people of mestizo origin enrolled after a complete ophthalmological evaluation at the National Institute of Ophthalmology, Lima-Peru. The morphometric parameters of the optic disc and thickness of the CFNR were measured by optical coherence tomography ZEISS CIRRUS(TM) HD-OCT Model 5000 (Carl Zeiss Inc., Dublin, CA, EE.UU). Megalopapilla was defined as: area of the optical disc greater than 2.5 mm2 and area greater than the mean plus 2 standard deviations. RESULTS: The areas obtained were: optical disc of 2.21 ± 0.43 mm2, neuroretinal ring of 1.37 ± 0.25 mm2, 0.84 ± 0.48 mm2 cup; mean cup/disc ratio of 0.58 ± 0.16, vertical cup/disc ratio of 0.55 ± 0.15, and a CFNR thickness of 100.30 ± 8.54 μm. The prevalence of megalopapilla, being considered as a disc area greater than 2.5 mm2 and 3.07, was 24% and 4%, respectively. When comparing megalopapilla with normal discs, the area of the ring (P = .08) and thickness of CFNR (P = .73) did not show statistically significant differences. CONCLUSION: The mean disc area was 2.21±0.43mm2 with a CFNR thickness of 100.30 ± 8.54 μm. The prevalence of megalopapilla was 24% and 4%, considering a disc area greater than 2.5 mm2 and 3.07 mm2, respectively. These results show that the megalopapilla and normal discs are similar in terms of ring area and CFNR thickness


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Fibras Nervosas , Disco Óptico/diagnóstico por imagem , Voluntários Saudáveis , Estudos Transversais , Disco Óptico/anatomia & histologia , Tamanho do Órgão , Peru/etnologia , Padrões de Referência , Retina/anatomia & histologia , Retina/diagnóstico por imagem , Estatísticas não Paramétricas , Tomografia de Coerência Óptica/métodos
7.
Invest Ophthalmol Vis Sci ; 60(14): 4792-4802, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31743936

RESUMO

Purpose: The purpose of this study was to describe the normative values, distribution patterns, and correlated factors of macular ganglion cell-inner plexiform layer (GCIPL), ganglion cell complex (GCC), and outer retinal layer (ORL) thicknesses in Chinese children. Methods: A sample of 3000 healthy children with different refractive status aged 6 to 19 years was consecutively examined. Demographics were recorded, and a comprehensive ophthalmic examination including refractive error and axial length (AL) was taken from all participants. The GCIPL, GCC, and ORL thicknesses were measured using swept source-optical coherence tomography (OCT), and multiple linear regression was used to determine which factors were associated with the thickness of each layer. Results: The average thickness was 77.00 ± 4.78 µm (95% confidence interval [CI]: 69.56-84.56 µm) in the GCIPL, 107.68 ± 5.95 µm (95% CI: 98.45-117.21 µm) in the GCC, and 178.57 ± 9.02 µm (95% CI: 164.33-192.56 µm) in the ORL. Multiple regression analysis indicated that GCIPL thickness was associated with sex (ß = 0.168, P < 0.001), age (ß = 0.126, P < 0.001), axial length (ß = -0.181, P < 0.001), and refractive error (ß = 0.233, P < 0.001). Age (ß = 0.154, P < 0.001), sex (ß = 0.102, P < 0.001), and refractive error (ß = 0.149, P < 0.001) were associated independently with GCC thickness after adjusting for the other factors. Furthermore, age (ß = 0.100, P < 0.001), sex (ß = 0.163, P < 0.001), AL (ß = -0.283, P < 0.001), and refractive error (ß = 0.207, P < 0.001) were the independent factors associated with ORL thickness. Conclusions: The present study established a normative pediatric database for macular layer thicknesses in healthy Chinese children, advancing the ability of OCT in diseases diagnosis and monitoring among children.


Assuntos
Grupo com Ancestrais do Continente Asiático/etnologia , Fibras Nervosas , Retina/anatomia & histologia , Células Ganglionares da Retina/citologia , Adolescente , Criança , China/epidemiologia , Estudos de Coortes , Feminino , Voluntários Saudáveis , Humanos , Masculino , Valores de Referência , Retina/diagnóstico por imagem , Tomografia de Coerência Óptica/métodos , Adulto Jovem
8.
Brain Behav Evol ; 93(4): 206-235, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31711060

RESUMO

Living holosteans, comprising 8 species of bowfins and gars, form a small monophyletic group of actinopterygian fishes, which are currently considered as the sister group to the enormously numerous teleosts and have largely been neglected in neuroanatomical studies. We have studied the catecholaminergic (CAergic) systems by means of antibodies against tyrosine hydroxylase (TH) and dopamine (DA) in the brain of representative species of the 3 genera included in the 2 orders of holostean fishes: Amia calva (Amiiformes) and Lepisosteus platyrhincus, Lepisosteus oculatus, and Atractosteus spatula (Lepisosteiformes). Different groups of TH/DA-immunoreactive (ir) cells were observed in the olfactory bulb, subpallium, and preoptic area of the telencephalon. Hypothalamic groups were labeled in the suprachiasmatic nucleus, tuberal (only in A. calva), retrotuberal, and retromamillary areas; specifically, the paraventricular organ showed only DA immunoreactivity. In the diencephalon, TH/DA-ir groups were detected in the prethalamus, posterior tubercle, and pretectum. In the caudal hindbrain, the solitary tract nucleus and area postrema presented TH/DA-ir cell groups, and also the spinal cord and the retina. Only in A. calva, particular CAergic cell groups were observed in the habenula, the mesencephalic tegmentum, and in the locus coeruleus. Following a neuromeric analysis, the comparison of these results with those obtained in other classes of fishes and tetrapods shows many common traits of CAergic systems shared by most vertebrates and in addition highlights unique features of actinopterygian fishes.


Assuntos
Encéfalo/anatomia & histologia , Encéfalo/metabolismo , Catecolaminas/metabolismo , Peixes/anatomia & histologia , Peixes/metabolismo , Animais , Neurônios/citologia , Neurônios/metabolismo , Retina/anatomia & histologia , Retina/metabolismo , Medula Espinal/anatomia & histologia , Medula Espinal/metabolismo
9.
Middle East Afr J Ophthalmol ; 26(3): 153-157, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31619903

RESUMO

PURPOSE: The purpose of the study was to evaluate the choroidal and retinal thicknesses in singleton versus twin pregnancies. MATERIALS AND METHODS: This study included 20 single and 20 twin pregnant women in their 3rd trimester with 20 age-matched healthy nonpregnant women as a control group. All participants underwent a detailed ocular examination. Cirrus enhanced depth imaging-optical coherence tomography was used for choroidal thickness (CT) with frame enhancement software. The study was divided into three groups: Group 1 - singleton pregnancy, Group 2 - twin pregnancy, and Group 3 - healthy nonpregnant controls. CT was measured from nasal, subfoveal, and temporal fields. RESULTS: Regarding CT, the twin pregnancy group had the thickest choroid followed by the singleton pregnancy group and control group. There was a statistically significant difference between Group 2 and Group 3 in terms of nasal, subfoveal, and temporal CTs (P = 0.002, P = 0.001, and P = 0.003, respectively). There was a statistically significant difference between Group 1 and Group 3 regarding just subfoveal CT (P = 0.028). Regarding retinal thickness, there was a statistically significant difference between Group 1 and Group 3 regarding the mean macular volume and ganglion cell-inner plexiform layer thicknesses (P < 0.05). Furthermore, regarding mean retinal nerve fiber layer thickness, there was a statistically significant difference between Group 1 and Group 2 and between Group 2 and Group 3 (P = 0.004, P = 0.003, respectively). CONCLUSION: Our study is the first one which evaluates choroidal and retinal thicknesses in twin pregnancies. We found that there was an increase in CT in the 3rd trimester of pregnancies and it was prominent in twin pregnancies.


Assuntos
Corioide/anatomia & histologia , Gravidez de Gêmeos , Retina/anatomia & histologia , Adulto , Corioide/diagnóstico por imagem , Feminino , Humanos , Fibras Nervosas , Gravidez , Terceiro Trimestre da Gravidez , Retina/diagnóstico por imagem , Células Ganglionares da Retina/citologia , Tomografia de Coerência Óptica/métodos
10.
Arch Soc Esp Oftalmol ; 94(12): 579-584, 2019 Dec.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-31594674

RESUMO

OBJECTIVE: To describe the morphometric characteristics and thickness of the retinal nerve fibre layer (CFNR) in healthy patients using optical coherence tomography. METHODS: A cross-sectional and descriptive study was conducted on a total of 184 eyes of 184 people of mestizo origin enrolled after a complete ophthalmological evaluation at the National Institute of Ophthalmology, Lima-Peru. The morphometric parameters of the optic disc and thickness of the CFNR were measured by optical coherence tomography ZEISS CIRRUS™ HD-OCT Model 5000 (Carl Zeiss Inc., Dublin, CA, EE.UU). Megalopapilla was defined as: area of the optical disc greater than 2.5 mm2 and area greater than the mean plus 2 standard deviations. RESULTS: The areas obtained were: optical disc of 2.21±0.43mm2, neuroretinal ring of 1.37±0.25mm2, 0.84±0.48mm2 cup; mean cup/disc ratio of 0.58±0.16, vertical cup/disc ratio of 0.55±0.15, and a CFNR thickness of 100.30±8.54µm. The prevalence of megalopapilla, being considered as a disc area greater than 2.5mm2 and 3.07, was 24% and 4%, respectively. When comparing megalopapilla with normal discs, the area of the ring (P=.08) and thickness of CFNR (P=.73) did not show statistically significant differences. CONCLUSION: The mean disc area was 2.21±0.43mm2 with a CFNR thickness of 100.30±8.54µm. The prevalence of megalopapilla was 24% and 4%, considering a disc area greater than 2.5 mm2 and 3.07 mm2, respectively. These results show that the megalopapilla and normal discs are similar in terms of ring area and CFNR thickness.


Assuntos
Fibras Nervosas , Disco Óptico/diagnóstico por imagem , Adulto , Idoso , Estudos Transversais , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Disco Óptico/anatomia & histologia , Tamanho do Órgão , Peru/etnologia , Padrões de Referência , Retina/anatomia & histologia , Retina/diagnóstico por imagem , Estatísticas não Paramétricas , Tomografia de Coerência Óptica/métodos
11.
World Neurosurg ; 130: e172-e187, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31252082

RESUMO

BACKGROUND: The central retinal artery (CRA) has been described as one of the first branches of the ophthalmic artery.It arises medial to the ciliary ganglion and after a sinuous path within the orbital cavity it penetrates the lower surface of the dura mater that covers the optic nerve, approximately 1 cm behind the eyeball. However, the numerous anatomic descriptions that were made of the CRA have been insufficient or unclear in relation to certain characteristics that are analyzed in the present study. METHODS: An electronic literature search was made in the PubMed database and a cadaver dissection was performed on 11 orbits fixed in formaldehyde. RESULTS: Results were obtained regarding the source, collateral branches, curves, direction, length of the optic nerve, dural perforation site, distance, path and relations, diameter, and area of the central artery of the retina. CONCLUSIONS: Our anatomic study innovates in 2 aspects of the CRA: area and curves. Not only was there a simple count of the number of curves, but it also analyzed the angle presented by each of the curves based on photos obtained in high definition, with a digital program to reduce the margin of error. These curvatures of the CRA were classified according to their spatial disposition within the orbital cavity based on a pattern that was easy to understand. Data were obtained from the area of the CRA on the penetration of the CRA into the dural sheath of the optic nerve.


Assuntos
Microcirurgia/métodos , Retina/anatomia & histologia , Retina/cirurgia , Artéria Retiniana/anatomia & histologia , Artéria Retiniana/cirurgia , Adulto , Feminino , Humanos , Masculino , Retina/patologia , Artéria Retiniana/patologia
12.
PLoS One ; 14(6): e0214347, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31211780

RESUMO

Dietary insufficiencies have been well documented to decrease growth rates and survival (and therefore overall production) in fish aquaculture. By contrast, the effects of dietary insufficiencies on the sensory biology of cultured fish remains largely unstudied. Diets based solely on plant protein sources could have advantages over fish-based diets because of the cost and ecological effects of the latter, but plant proteins lack the amino acid taurine. Adequate levels of taurine are, however, necessary for the development of a fully functional visual system in mammals. As part of ongoing studies to determine the suitability of plant-based diets, we investigated the effects of normal and reduced taurine dietary levels on retinal anatomy and function in European sea bass (Dicentrarchus labrax). We could not demonstrate any effects of dietary taurine level on retinal anatomy, nor the functional properties of luminous sensitivity and temporal resolution (measured as flicker fusion frequency). We did, however, find an effect on spectral sensitivity. The peak of spectral sensitivity of individuals fed a 5% taurine diet was rightward shifted (i.e., towards longer wavelengths) relative to that of fish fed a 0% or 1.5% taurine diet. This difference in in spectral sensitivity was due to a relatively lower level of middle wavelength pigment (maximum absorbance .500 nm) in fish fed a 5% taurine diet. Changes in spectral sensitivity resulting from diets containing different taurine levels are unlikely to be detrimental to fish destined for market, but could be in fishes that are being reared for stock enhancement programs.


Assuntos
Bass/fisiologia , Taurina/administração & dosagem , Visão Ocular/efeitos dos fármacos , Ração Animal , Animais , Peso Corporal/efeitos dos fármacos , Pesqueiros , Retina/anatomia & histologia , Retina/efeitos dos fármacos , Retina/fisiologia , Taurina/farmacologia
13.
Georgian Med News ; (287): 39-44, 2019 Feb.
Artigo em Russo | MEDLINE | ID: mdl-30958286

RESUMO

The purpose of this research is to study the effect of preeclampsia of pregnant women on the functional status of the visual organ. The research study was made on 77 pregnant women (154 eyes) from 17 to 43 years old. Based on the analysis of the research results, during uncomplicated pregnancy and mild preeclampsia we found no significant changes in the foveolar retinal thickness and macular retinal volume both during various trimesters of pregnancy and postpartum. In moderate preeclampsia along with spasm of retinal arterioles and congestion in the venous bed in the third trimester, there was a statistically significant increase in the average thickness of the foveolar retina (183.8±4.2 micron versus 158.6±4.4 and 157.8±4.1 micron respectively in the control and in the comparison group, p<0.05); 57% of the eyes have a significant increase of the average FRT data (7.38±0.05 mm³ versus 7.01±0.02 mm³ in the comparison and control groups, p<0.05); in one case, the macula oedema was determined by ophthalmoscopy. In this group, the highest increase of the foveal retina thickness and the increase of the macular retina volume (198.3±4.5 micron, and 7.90±0.07 mm³, p<0.05) were observed. After 2-4 months postpartum in the subgroups of moderate and severe preeclampsia, there was a reduction in the average values of foveal retinal thickness and macular retinal volume, although the mean MRV values still significantly exceeded the baseline, and in 10 eyes FRT elevated remained indices. Changes in the retina morphometric parameters directly correlated with the severity of preeclampsia. Identified changes in the macular retina must be considered when predicting the risk of the macular pathology formation many years postpartum.


Assuntos
Pré-Eclâmpsia/patologia , Retina/anatomia & histologia , Retina/fisiologia , Tomografia de Coerência Óptica , Adolescente , Adulto , Feminino , Humanos , Edema Macular/fisiopatologia , Gravidez , Adulto Jovem
14.
Anat Histol Embryol ; 48(3): 177-200, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30734347

RESUMO

The cellular structure and functional relevance of the bird fovea are still incompletely understood. This review gives an overview of the cellular composition of the bird fovea, with special regard to Müller glial cells that provide the mechanical stability of the foveal tissue. A survey of previous data shows that the visual acuity of different bird groups (with the exception of owls) depends on the eye size, while the shape of the foveal pit does not correlate with the visual acuity. Among various bird groups, the foveal pit may have two depths, shallow (80-120 µm) or deep (190-240 µm). There is a long-lasting debate whether the bird fovea acts as a local image enlarger or as a focus indicator and movement detector. These functions are supported by the refraction of the incoming light at the tissue surface. However, it was shown that Müller cells form highly refractive layers in the centre and walls of the deep avian fovea (Nature, 1978, 275, 127). Analysis of the light path through the tissue may suggest that Müller cell layers serve at least two optical functions: magnification of the image in the foveal centre and light focusing into a point within and/or a ring around the foveal centre. It is suggested that Müller glial cells contribute to various optical functions of the bird fovea.


Assuntos
Aves/anatomia & histologia , Aves/fisiologia , Fóvea Central/anatomia & histologia , Fóvea Central/fisiologia , Animais , Águias/anatomia & histologia , Águias/fisiologia , Neuroglia/citologia , Neuroglia/fisiologia , Células Fotorreceptoras de Vertebrados/citologia , Células Fotorreceptoras de Vertebrados/fisiologia , Retina/anatomia & histologia , Retina/fisiologia , Estrigiformes/anatomia & histologia , Estrigiformes/fisiologia
15.
Cell ; 176(5): 1222-1237.e22, 2019 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-30712875

RESUMO

High-acuity vision in primates, including humans, is mediated by a small central retinal region called the fovea. As more accessible organisms lack a fovea, its specialized function and its dysfunction in ocular diseases remain poorly understood. We used 165,000 single-cell RNA-seq profiles to generate comprehensive cellular taxonomies of macaque fovea and peripheral retina. More than 80% of >60 cell types match between the two regions but exhibit substantial differences in proportions and gene expression, some of which we relate to functional differences. Comparison of macaque retinal types with those of mice reveals that interneuron types are tightly conserved. In contrast, projection neuron types and programs diverge, despite exhibiting conserved transcription factor codes. Key macaque types are conserved in humans, allowing mapping of cell-type and region-specific expression of >190 genes associated with 7 human retinal diseases. Our work provides a framework for comparative single-cell analysis across tissue regions and species.


Assuntos
Fóvea Central/fisiologia , Primatas/fisiologia , Retina/fisiologia , Idoso , Animais , Callithrix , Feminino , Humanos , Macaca , Masculino , Retina/anatomia & histologia , Células Ganglionares da Retina/metabolismo
16.
Vet Ophthalmol ; 22(1): 93-97, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29888430

RESUMO

PURPOSE: To establish whether there is cone contribution to retinal function and structure in chinchillas (Chinchilla lanigera), in view of the prevailing notion that this species possesses a pure rod retina. METHODS: Photopic electroretinography (ERG) responses to high-intensity flashes (10 and 25 cd*s/m2 ) were recorded unilaterally in six pigmented chinchillas following 10 minutes of light adaptation (30 cd/m2 ). Retinas of two animals were studied histologically, and immunohistochemistry (IHC) was conducted to detect the presence of short and medium/long wavelength cone photoreceptors. RESULTS: ERG recordings revealed photopic responses, albeit of low amplitudes. Histopathology demonstrated presumptive cone inner segments in the photoreceptor layer. Presence of cone photoreceptors was confirmed by IHC. Cone density was higher in the central retina, and red/green cones outnumbered blue cones. CONCLUSIONS: Our results provide convincing evidence for the presence of functioning cone photoreceptors in the chinchilla retina, disproving the established belief that the species has a pure rod retina.


Assuntos
Chinchila/anatomia & histologia , Retina/anatomia & histologia , Animais , Eletrorretinografia/veterinária , Células Fotorreceptoras Retinianas Bastonetes
17.
Vet Ophthalmol ; 22(1): 88-92, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29749697

RESUMO

OBJECTIVE: To describe an indirect funduscopy imaging technique for dogs and cats using low cost and widely available equipment: a smartphone, a three-dimensional (3D) printed indirect lens adapter, and a 40 diopters (D) indirect ophthalmoscopy lens. METHODS: Fundus videography was performed in dogs and cats using a 40D indirect ophthalmoscopy lens and a smartphone fitted with a 3D printed indirect lens adapter. All animals were pharmacologically dilated with topical tropicamide 1% solution. Eyelid opening and video recording were performed using standard binocular indirect ophthalmoscopy technique. All videos were uploaded to a computer, and still images were selected and acquired for archiving purposes. Fundic images were manipulated to represent the true anatomy of the fundus. RESULTS: It was possible to promptly obtain good quality images from normal and diseased retinas using the nonpatented 3D printed, lens adapter for a smartphone. CONCLUSIONS: Fundic imaging using a smartphone can be performed with minimal investment. This simple imaging modality can be used by veterinary ophthalmologists and general practitioners to acquire, archive, and share images of the retina. The quality of images obtained will likely improve with developments in smartphone camera software and hardware.


Assuntos
Gatos/anatomia & histologia , Técnicas de Diagnóstico Oftalmológico/veterinária , Cães/anatomia & histologia , Oftalmoscopia/veterinária , Retina/anatomia & histologia , Smartphone/instrumentação , Animais , Técnicas de Diagnóstico Oftalmológico/instrumentação , Fundo de Olho
18.
Eur J Ophthalmol ; 29(4): 386-393, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30178682

RESUMO

PURPOSE: The aim of this study is to evaluate the variability of central retinal thickness asymmetry in healthy Caucasian adults with the posterior pole asymmetry analysis to serve as a reference. METHODS: In total, 404 eyes of 202 subjects who aged between 18 and 80 years, who had no ocular pathology, were included in this cross-sectional observational study. Retinal thickness maps with posterior pole asymmetry analysis mode were taken with the optical coherence tomography (SPECTRALIS SD-OCT; Heidelberg Engineering). Superior and inferior hemifields were divided into five zones resembling to the strategy in Glaucoma Hemifield Test. Mean retinal thickness in each of the five zones was compared with the thickness of the corresponding zone in each eye (paired-samples t-test), and differences in retinal thickness (DRT1-5) and ganglion cell layer thickness between reciprocal locations were measured. Differences in retinal thickness values of two eyes of each subject were also compared (independent-samples t-test). RESULTS: The intra-eye asymmetry was statistically significant in zones 4 and 5. The highest mean intraocular differences in retinal thickness were 5.8 µm (zone 5) in all eyes, 5.8 µm (zone 5) in the right eyes, and 5.9 µm (zones 4 and 5) in the left eyes. The only statistically significant interocular local differences in retinal thickness asymmetries were found in zone 3. The intraocular asymmetry in retinal thickness was found to be the lowest in zone 1. The differences of ganglion cell layer thickness (GCLTs) were not statistically significant. CONCLUSION: There were statistically significant physiological inter-eye asymmetry in zone 3 and intra-eye asymmetries in zones 4 and 5. These measurements must be considered during screening for glaucoma with posterior pole asymmetry analysis in the Caucasian population.


Assuntos
Grupo com Ancestrais do Continente Europeu , Retina/anatomia & histologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Axônios/fisiologia , Estudos Transversais , Análise de Dados , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Retina/diagnóstico por imagem , Células Ganglionares da Retina/citologia , Tomografia de Coerência Óptica/métodos , Adulto Jovem
19.
J Fish Biol ; 94(2): 297-312, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30565257

RESUMO

We systematically analysed the characteristics of the Cyclopterus lumpus eye and retina during cultured post-hatch developmental stages using gross observations, histology, immunohistochemistry, microscopy, fundus imaging and spectral domain optical coherence tomography retinal imaging. Post-hatch developing cultured C. lumpus eye and retinal tissues share a number of features typically conserved in other teleost fish. However, cultured C. lumpus possess some novel ocular and retinal features different from previous descriptions of other teleosts, including a prominent retractor lentis pigmented tissue closely associated with the vascular rete mirabile, peripherally located lobes of separate retinal tissue containing proliferative cells, extensive tapetum material of varying thickness, prominent fundus stripes and an elongated rod-shaped optic nerve stalk. Post-hatch developing cultured C. lumpus also developmentally regulate a protein homologous to alpha smooth-muscle actin in strikingly dense continuous bands in the plexiform layers of the retina. The novel features of the eye and retina of cultured C. lumpus described here could contribute to our understanding of fitness and survival of C. lumpus in a widely ranging habitat.


Assuntos
Perciformes/crescimento & desenvolvimento , Retina/crescimento & desenvolvimento , Animais , Aquicultura , Peixes , Larva/anatomia & histologia , Perciformes/anatomia & histologia , Retina/anatomia & histologia , Tomografia de Coerência Óptica
20.
Adv Exp Med Biol ; 1085: 3-5, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30578474

RESUMO

The wall of the eye consists of three layers: the sclera (the outermost layer), the choroid (the middle layer), and the retina (the innermost layer).


Assuntos
Corioide/anatomia & histologia , Retina/anatomia & histologia , Esclera/anatomia & histologia , Técnicas Histológicas , Humanos
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