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Background and Aim: Stem cell therapy is considered a promising treatment for several neurodegenerative diseases. However, there are very few studies on the use of this therapy in glaucoma models. By detecting the changes produced by glaucoma early, cell therapy could help prevent the events that lead to blindness. In this study, early changes in the optic nerve head (ONH) as detected by optical coherence tomography (OCT) after the application of human Wharton's jelly-derived mesenchymal stromal cells (hWJ-MSCs) in an experimental model of ocular hypertension (OH) were evaluated. Materials and Methods: Fifteen New Zealand rabbits were randomly divided into the following three groups: G1: OH, G2: hWJ-MSCs, and G3: OH + hWJ-MSCs. An OH model was constructed, and the intraocular pressure (IOP) was measured regularly. At week 7, 105/100 µL hWJ-MSCs were intravitreally injected. Retinography and OCT were used to evaluate structural changes in ONH. Results: IOP increased significantly in G1 and G3 from week 3 onward. Retinography revealed more significant optic nerve changes, that is, papillary asymmetry suggestive of optic nerve excavation, vascular alterations, and irregular hypopigmentation peripheral to the optic disk margin, in G1 compared with G3. OH locates the hWJ-MSCs solution in the vitreous in front of the optic nerve. OCT revealed retinal nerve fiber layer (RNFL) reduction in all groups, reduced optic cup volume in G2 and G3 between weeks 1 and 9, and significant ganglion cell layer thickness reduction in G1 and a slight increase in G3. Conclusion: Intravitreal hWJ-MSCs injection produced changes in optic cup volume, which were detected early on by OCT; however, RNFL could not be restored in this OH model.
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Collagen architecture determines the biomechanical environment in the eye, and thus characterizing collagen fiber organization and biomechanics is essential to fully understand eye physiology and pathology. We recently introduced instant polarized light microscopy (IPOL) that encodes optically information about fiber orientation and retardance through a color snapshot. Although IPOL allows imaging collagen at the full acquisition speed of the camera, with excellent spatial and angular resolutions, a limitation is that the orientation-encoding color is cyclic every 90 degrees (π/2 radians). In consequence, two orthogonal fibers have the same color and therefore the same orientation when quantified by color-angle mapping. In this study, we demonstrate IPOLπ, a new variation of IPOL, in which the orientation-encoding color is cyclic every 180 degrees (π radians). Herein we present the fundamentals of IPOLπ, including a framework based on a Mueller-matrix formalism to characterize how fiber orientation and retardance determine the color. The improved quantitative capability of IPOLπ enables further study of essential biomechanical properties of collagen in ocular tissues, such as fiber anisotropy and crimp. We present a series of experimental calibrations and quantitative procedures to visualize and quantify ocular collagen orientation and microstructure in the optic nerve head, a region in the back of the eye. There are four important strengths of IPOLπ compared to IPOL. First, IPOLπ can distinguish the orientations of orthogonal collagen fibers via colors, whereas IPOL cannot. Second, IPOLπ requires a lower exposure time than IPOL, thus allowing faster imaging speed. Third, IPOLπ allows visualizing non-birefringent tissues and backgrounds from tissue absorption, whereas both appear dark in IPOL images. Fourth, IPOLπ is cheaper and less sensitive to imperfectly collimated light than IPOL. Altogether, the high spatial, angular, and temporal resolutions of IPOLπ enable a deeper insight into ocular biomechanics and eye physiology and pathology.
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Purpose: To report a longitudinal OCT study of optic nerve head (ONH) neural canal remodeling in a young adult subject's eyes through the progression of early refractive myopia. Observations: Deep ONH changes early in the progression of myopia included enlargement of the Bruch's membrane opening, progressive temporal displacement of BMO relative to the anterior scleral canal opening, choroidal border tissue remodeling and exposure of the temporal scleral flange within the ONH neural canal of both eyes. Conclusions and Importance: Longitudinal OCT imaging of a young adult subject suggest that OCT is able to detect ONH neural canal remodeling early in the progression of refractive myopia that shares key features previously described only in more highly myopic eyes.
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Glaucoma is a neurodegenerative disease that affects the retinal ganglion cells (RGCs) and leads to progressive vision loss. The first pathological signs can be seen at the optic nerve head (ONH), the structure where RGC axons leave the retina to compose the optic nerve. Besides damage of the axonal cytoskeleton, axonal transport deficits at the ONH have been described as an important feature of glaucoma. Axonal transport is essential for proper neuronal function, including transport of organelles, synaptic components, vesicles, and neurotrophic factors. Impairment of axonal transport has been related to several neurodegenerative conditions. Studies on axonal transport in glaucoma include analysis in different animal models and in humans, and indicate that its failure happens mainly in the ONH and early in disease progression, preceding axonal and somal degeneration. Thus, a better understanding of the role of axonal transport in glaucoma is not only pivotal to decipher disease mechanisms but could also enable early therapies that might prevent irreversible neuronal damage at an early time point. In this review we present the current evidence of axonal transport impairment in glaucomatous neurodegeneration and summarize the methods employed to evaluate transport in this disease.
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Glaucoma , Doenças Neurodegenerativas , Animais , Transporte Axonal , Axônios/metabolismo , Modelos Animais de Doenças , Glaucoma/metabolismo , Doenças Neurodegenerativas/metabolismo , Células Ganglionares da Retina/patologiaRESUMO
PURPOSE: To evaluate Bruch's membrane opening - minimum rim width (BMO-MRW) and peripapillary retinal nerve fiber layer thickness (RNFLT) following an acute primary angle-closure attack (APAC). MATERIALS AND METHODS: Nine consecutive patients with unilateral APAC were included. Patients with a bilateral attack, with signs of glaucomatous optic nerve damage or evidence of a previous APAC in either eye were excluded. Three months after the attack, all eyes underwent BMO-MRW and RNFLT measurements with SDOCT. APAC eyes were compared to the contralateral eyes. RESULTS: Three months after the attack, mean BMO-MRWs were 281.22 ± 56.88â µm and 313.78 ± 43.48â µm (P = 0.009) and mean RNFLTs were 78 ± 15.36â µm vs 95.78 ± 10.81â µm (P = 0.008) in the APAC and contralateral eyes, respectively. RNFLT and BMO-MRW measurements had a strong positive correlation (R = 0.7436, P = 0.013). APAC eyes had a shorter axial length (21.85 ± 1.21 vs 22 ± 1.07, P = 0.042) and shallower anterior chamber depth (2.29 ± 0.21 vs 2.41 ± 0.12, P = 0.039) than contralateral eyes. IOP at presentation showed a strong negative correlation with both BMO-MRW (R = -0.7669, P = 0.009) and RNFLT measurements (R = -0.7723, P = 0.008). CONCLUSION: BMO-MRW and RNFLT measurements are significantly reduced 3 months after an APAC when compared to the contralateral eye. IOP at presentation may have an impact on the reduction of these parameters.
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Lâmina Basilar da Corioide , Disco Óptico , Doença Aguda , Humanos , Pressão Intraocular , Fibras Nervosas , Células Ganglionares da Retina , Tomografia de Coerência ÓpticaRESUMO
CLINICAL CASE: Forteen year old patient presenting progressive decrease in visual acuity of the left eye after 3 months of evolution. On examination he presents bilateral drusen of papilla, associated with juxtapapillary neovascular membrane, which seriously compromises the vision and visual field of the left eye. RESULT: Treatment with 3 consecutive injections of intravitreal ranibizumab resulted in the inactivation of the neovascular membrane with reabsorption of subretinal fluid and improvement of the best corrected visual acuity of the left eye. After 9 months of follow-up, it was 20/20 and stable. CONCLUSION: Although optic nerve head drusen are considered benign, neovascular membranes can be a complication. Anti-VEGFs are an effective alternative for treatment.
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Inibidores da Angiogênese/uso terapêutico , Neovascularização de Coroide/tratamento farmacológico , Drusas do Disco Óptico/tratamento farmacológico , Ranibizumab/uso terapêutico , Adolescente , Neovascularização de Coroide/complicações , Feminino , Humanos , Drusas do Disco Óptico/etiologiaRESUMO
PURPOSE: To evaluate the hypotenuse of the vertical optic nerve head cup (HVOC), measured using the length and depth of the cup obtained with enhanced depth imaging spectral-domain optic coherence tomography (SD-OCT), as a biomarker for glaucoma diagnosis. METHODS: This was a prospective cross-sectional study of patients with glaucoma and controls. SD-OCT was performed in all participants to assess average circumpapillary retinal nerve fiber layer (RNFL) thickness. A vertical B-scan of the optic nerve head (ONH) was obtained for HVOC measurement. The length and depth of the optic nerve cup formed the sides of a right triangle that were used to calculate the HVOC. Participants also underwent standard automated perimetry. RESULTS: One hundred and fifty-six eyes were divided into three groups: mean deviation (MD) <-7 dB (60 eyes); MD ≥-7 dB (74 eyes); and healthy subjects (22 eyes). The mean (SD) HVOC in these groups was 1,419.8 (347.2) µm, 1,234.6 (258.8) µm, and 685.79 (315.4) µm (P<0.01), respectively. In the secondary structure-function analysis, only discs with a vertical diameter of 1.51-2.00 mm were included (120 eyes). The HVOCs were divided into four percentile groups, with the following means: 940, 1,128, 1,390, and 1,662 µm. There was a significant difference in MD between percentile groups 1 and 3 (P<0.03), 1 and 4 (P<0.001), 2 and 3 (P<0.02), and 2 and 4 (P<0.001). RNFL thickness differed among all percentile groups (P<0.001). CONCLUSION: HVOC may provide an additional morphometric biomarker for the structural evaluation of ONH remodeling in glaucoma.
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PURPOSE: To investigate the reproducibility of Bruch's membrane opening minimum rim width (BMO-MRW) and retinal nerve fibre layer thickness (RNFLT) measurements using spectral domain optical coherence tomography (SD-OCT). Additionally, to investigate the reproducibility of BMO area measurements and fovea to BMO centre (FoBMO) angle. METHODS: Participants were healthy subjects (n = 30) and patients with glaucoma (n = 26). One eye of each participant was scanned to obtain optic nerve head (24 radial B-scans) and peripapillary (one circular B-scan) images by three independent examiners. Additionally, one examiner imaged each participant three times on the same day. Intra- and interobserver reproducibilities were estimated by within-subject standard deviation (SW) and coefficient of variation (COV). Spearman's rank correlation coefficient was used to test the correlation between the magnitude of the parameter and its standard deviation. RESULTS: The global BMO-MRW COVs (%) in healthy/glaucoma subjects were 0.87/1.34 and 1.28/3.13 for intra- and interobserver analyses, respectively, and the corresponding global RNFLT figures were 1.50/2.10 and 2.04/2.87. Global mean BMO-MRW and RNFLT showed no correlation with their respective standard deviations. The reproducibilities of BMO area and FoBMO angle were excellent and similar between the groups. CONCLUSION: The reproducibilities of BMO-MRW, BMO area measurements and FoBMO angle were excellent in both healthy subjects and patients with glaucoma. Bruch's membrane opening minimum rim width (BMO-MRW) reproducibility is comparable to that of RNFLT measurements.
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Lâmina Basilar da Corioide/patologia , Glaucoma de Ângulo Aberto/diagnóstico , Pressão Intraocular , Células Ganglionares da Retina/patologia , Tomografia de Coerência Óptica/métodos , Campos Visuais , Adulto , Idoso , Estudos Transversais , Feminino , Glaucoma de Ângulo Aberto/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Fibras Nervosas/patologia , Disco Óptico/patologia , Curva ROC , Reprodutibilidade dos TestesRESUMO
El objetivo de este trabajo fue determinar el tamaño del disco óptico por tomografía de coherencia óptica (TCO), en una población mayor de 40 años, que asistió a control rutinario oftalmológico desde noviembre el 2015 a febrero del 2016 y que no tenían antecedentes conocidos de glaucoma ni de enfermedades sistémicas. Fueron incluidos en el estudio 52 pacientes que asistieron a la consulta externa de oftalmología de la Fundación Visión, por un examen de rutina. Se le diligenció una historia clínica completa, donde se indagaron los antecedentes patológicos tanto sistémicos como oculares. Se realizó la toma de la agudeza visual utilizando la cartilla de Snellen en cada ojo por separado a 6 metros del paciente, refracción automatizada, prueba refractiva, biomicroscopía en lámpara de hendidura con énfasis en la profundidad de la cámara anterior. Se excluyeron pacientes con cámaras anteriores pandas o estrechas (utilización de gonioscopio mirrow 4 mini) y presión intraocular elevada. Luego de la instilación de Tropicamida 0,5%/Fenilefrina HCL 5% en cada ojo y evaluación del polo posterior en lámpara de hendidura con lente de 90D Superfield, se realizó la Tomografía de coherencia óptica con el equipo The ZEISS Cirrus(tm) HD-TCO Model 4000 (Cirrus HD-TCO).
The objective of this study was to determine the size of the optic nerve by opticalcoherence tomography (TCO) in a population older than 40 years old who attendedroutine ophthalmological control from November 2015 to February 2016 and did not haveknown records of glaucoma or systemic. Fifty two patients were included in the study whoatended the external consulting room of ophthalmology of the Foundation Vision for aroutine control. A full medical history was completed, where the systemic and ocularpathologic records were investigated. Visual acuity test was performed using Snellen chartin each patient separately at 6 meters from the patinet. Automatic refraction, retractiontest, slit lamp biomicroscopy with emphasis in the anterior chamber depth were alsoperformed. Patients with narrow or panda anterior chambers (using the mini 4 mirrorgonioscope and high intraocular pressure were excluded. After instillation of tropicamide0.5%/phenylephrine HCL 5% in each eye and evaluation of the posterior pole in slit lampwith 90D Superfield lens, the optic coherence tomography was made using a ZEISSCirrus HD-TCO Model 4000 (Cirrus HD-TCO).
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Humanos , Masculino , Adulto , Feminino , Pessoa de Meia-Idade , Idoso , Nervo Óptico , Tomografia Óptica , Disco ÓpticoRESUMO
Se realizó una revisión bibliográfica con el objetivo de ampliar el conocimiento sobre la maculopatía relacionada con la foseta del nervio óptico, su fisiopatología, así como sus principales manifestaciones, diagnóstico clínico, angiográfico y por tomografía de coherencia óptica, y describir algunos de los tratamientos que se han utilizado recientemente a nivel mundial. Se tuvieron en cuenta las tendencias actuales de tratamiento. Se consultaron fundamentalmente artículos científicos de revistas publicados en las bases de datos PubMED y Cochrane, así como textos básicos que abordan este tema en los últimos 5 años, a través de Google como motor de búsqueda. A pesar de que se trata de una enfermedad infrecuente, su manejo suele resultar difícil, especialmente cuando existe afectación macular. En nuestro trabajo constatamos que la mayoría de los estudios utilizan muestras pequeñas, son retrospectivos, no comparativos y no ramdomizados. Sin embargo, se encontraron modalidades de tratamiento que han sido utilizadas por años y más recientemente descripciones de nuevas técnicas que requerirán futuros estudios. No existe un consenso sobre un protocolo ideal de tratamiento para esta entidad(AU)
A literature review was made to expand knowledge on the optic nerve head pit-related maculopathy, its physiopathology and main manifestations, clinical and angiographic diagnosis, optical coherence tomography, and to describe some of the treatments recently used worldwide. The current therapeutic tendencies were taken into account. The fundamental sources of information were scientific articles from journals in PubMED and Cochrane databases as well as basic texts which dealt with this topic in the last five years through Google search engine. Despite the rare occurrence of the disease, its management may be difficult particularly in macular effect cases. This paper confirmed that most of the studies used small samples, were retrospective, non-comparative and non-randomized. However, some therapeutic modalities were found, which have been used for years and also descriptions of new techniques that require further research. There is no consensus on the ideal treatment protocol for this disease(AU)
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Humanos , Idoso , Bases de Dados Bibliográficas/estatística & dados numéricos , Degeneração Macular/patologia , Nervo Óptico/anormalidades , Literatura de Revisão como Assunto , Tomografia de Coerência Óptica/métodosRESUMO
PURPOSE: To analyze the influence of manual correction of the automatically determined edge of the optic nerve head (ONH) in optic disc measurements in cases in which the optical coherence tomography did not identify the disc limits correctly. METHODS: The study included 127 eyes from 127 consecutive patients with glaucoma, suspects, and healthy individuals. In a retrospective analysis, eyes that underwent testing with the Stratus OCT (software version 4.0, Carl Zeiss Meditec, Dublin, CA, USA) Fast Optic Disc protocol were evaluated. Forty-seven eyes in which either the manual assignment was not necessary or the signal strength was below six were excluded. After image acquisition and processing, one expert examiner manually corrected the determination of the edge of the ONH, identified as the end of the retinal pigment epithelium/choriocapillaris complex. Disc area, cup area, rim area, and cup/disc area ratio results were compared before and after the optic disc margin manually corrected determination. Paired t-test was performed to evaluate the differences, and Bland-Altman plots were used to display the relationships between measurements. RESULTS: Eighty eyes from 80 individuals were included in the analyses. No statistically signifiant difference (P=.538) was found when analyzing results obtained with automated and manual determination of rim area (mean ± standard deviation; 1.30±0.45 mm(2) and 1.29±0.39 mm(2), respectively). Cup area (1.39±0.58 mm(2) and 1.31±0.55 mm(2), respectively), cup/disc area ratio (0.50±0.16 mm(2) and 0.49±0.15 mm(2), respectively), and disc area results (2.69±0.55 mm(2) and 2.60±0.51 mm(2), respectively) were significantly different. CONCLUSION: The Stratus OCT ONH Report results were little influenced when optic disc limits were manually determined. Therefore the standard automated Stratus OCT disc margin assignment is adequate, and manual correction is not necessary.
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Glaucoma is a leading cause of blindness worldwide, characterised by specific visual field defects due to the degeneration of retinal ganglion cells and damage to the optic nerve head (ONH). Elevated intraocular pressure (IOP) is the most important risk factor for glaucoma development. One of the clinical hallmarks of glaucomatous optic neuropathy is the excavation of the ONH, which consists of a progressive posterior displacement of the ONH surface and excavation of the pre-laminar tissues beneath the anterior-most aspect of the scleral canal, known as the anterior scleral ring. Radial optic neurotomy (RON) is a surgical technique that has been proposed for treating central retinal vein occlusion. While the original rationale of RON was the relief of increased tissue pressure within the optic nerve that results from occlusion of the central retinal vein, recent results are discussed here which suggest that by relaxing of the scleral ring of the prelaminar and laminar regions of the ONH, RON may alleviate the IOP-related connective tissue stress, and in turn, prevent the onset and reduce the progression of glaucomatous neuropathy.