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1.
Vestn Oftalmol ; 139(3. Vyp. 2): 96-106, 2023.
Artigo em Russo | MEDLINE | ID: mdl-37144375

RESUMO

Glaucoma is one of the most difficult and significant ocular conditions. The chronic asymptomatic course of glaucoma progression leads to irreversible deterioration of visual functions. Many aspects of its pathogenesis, the features of its clinical presentation, diagnosis and treatment have been identified in recent years. The results of diagnostic methods: tonometry, perimetry, optical coherence tomography - with glaucoma do not have high specificity due to the large diversity of the population. When determining the target intraocular pressure (IOP), we look at the indicators of the choroidal blood flow and biomechanical stress of the cornea and sclera (fibrous membrane of the eye). Studying visual functions is important in the diagnosis and monitoring of glaucoma. The creation of a modern portable device based on a virtual reality helmet allows examination of patients with low central vision. Structural changes in glaucoma affect the optic disc and the inner retinal layers. The proposed classification of atypical discs allows determining the earliest characteristic changes in the neuroretinal rim for glaucoma in cases of difficult diagnosis. The complexity of the diagnosis of glaucoma is also associated with concomitant pathologies in elderly patients. In cases with comorbidity of primary glaucoma and Alzheimer's disease the structural and functional changes revealed by modern research methods for glaucoma are explained by both the process of secondary transsynaptic degeneration and the death of neurons as a result of an increased IOP. The starting treatment is and its type are fundamentally important for preserving visual functions. Drug therapy with prostaglandin analogues contributes to a significant and persistent decrease in the level of IOP, and mainly by utilizing the uveoscleral outflow pathway. Surgical treatment of glaucoma is an effective way to achieve the target IOP values. However, postoperative hypotension affects the bloodstream both in the central and peripapillary retina. Optical coherence tomography angiography helped establishe that the strongest factor that determines postoperative changes is the difference in IOP, not its absolute level.


Assuntos
Glaucoma de Ângulo Aberto , Glaucoma , Disco Óptico , Humanos , Idoso , Glaucoma de Ângulo Aberto/diagnóstico , Glaucoma/diagnóstico , Glaucoma/etiologia , Glaucoma/terapia , Disco Óptico/patologia , Pressão Intraocular , Testes de Campo Visual , Tomografia de Coerência Óptica/métodos
2.
Sensors (Basel) ; 23(9)2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-37177707

RESUMO

The present manuscript introduces an investigation of the structural and functional changes in the optic nerve in patients undergoing glaucoma treatment by comparing optical coherence tomography (OCT) measurements and RETeval system parameters. For such a purpose, 140 eyes were examined at the Ophthalmology Clinic of the "Elpis" General Hospital of Athens between October 2022 and April 2023. A total of 59 out of 140 eyes were from patients with early glaucoma under treatment (case group), 63 were healthy eyes (control group) and 18 were excluded. The experimental measurements were statistically analyzed using the SPSS software package. The main outcomes are summarized below: (i) there was no statistical difference between the right and left eye for both groups, (ii) statistical differences were found between age interval subgroups (30-54 and 55-80 years old) for the control group, mainly for the time response part of the RETeval parameters. Such difference was not indicated by the OCT system, and (iii) a statistical difference occurred between the control and case group for both OCT (through the retinal nerve fiber layer-RNFL thickness) and the RETeval parameters (through the photopic negative response-PhNR). RNFL was found to be correlated to b-wave (ms) and W-ratio parameters. In conclusion, the PhNR obtained by the RETeval system could be a valuable supplementary tool for the objective examination of patients with early glaucoma.


Assuntos
Glaucoma , Disco Óptico , Humanos , Tomografia de Coerência Óptica/métodos , Disco Óptico/diagnóstico por imagem , Retina , Nervo Óptico/diagnóstico por imagem , Glaucoma/diagnóstico por imagem
3.
J Neurol Sci ; 449: 120661, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37126919

RESUMO

PURPOSE: Giant cell arteritis (GCA) involving ophthalmic circulation often manifests as anterior ischemic optic neuropathy (AAION), presenting with severe vision loss and pallid optic disc edema. Non-arteritic anterior ischemic optic neuropathy (NAION) classically presents with segmental optic disc edema and corresponding altitudinal visual field defect (VFD) with small cup-to-disc ratio in the fellow eye. Differentiating these two entities is critical as GCA requires immediate treatment to prevent vision loss in the fellow eye. This study investigated how often GCA mimics NAION at presentation. METHODS: Retrospective chart review of patients with temporal artery biopsy (TAB) positive GCA with ocular manifestations seen at a tertiary neuro-ophthalmology practice between 2015 and 2020. Patients presenting with segmental non-pallid optic disc swelling and corresponding altitudinal VFD mimicking NAION were identified. RESULTS: The clinical presentation of 7.1% (3/42) of patients with TAB-positive GCA mimicked NAION. Two of three patients had cup-to-disc ratio of <0.3 in the fellow eye. Two patients were women, mean age was 67.3 ± 6.5 years, and mean presenting visual acuity was 0.45 ± 0.48 LogMAR. Two patients had a normal temporal artery ultrasound. Two of three patients had at least one systemic symptom of GCA at presentation and all had elevation of one or both inflammatory markers. CONCLUSIONS: There should be high index of suspicion for GCA, even in patients highly suspected to have NAION. Inflammatory markers must be checked in every patient with presumed NAION and TAB performed if one or both are elevated to avoid missing GCA.


Assuntos
Arterite de Células Gigantes , Disco Óptico , Neuropatia Óptica Isquêmica , Papiledema , Humanos , Feminino , Pessoa de Meia-Idade , Idoso , Masculino , Arterite de Células Gigantes/complicações , Arterite de Células Gigantes/diagnóstico , Arterite de Células Gigantes/patologia , Neuropatia Óptica Isquêmica/diagnóstico , Papiledema/complicações , Papiledema/patologia , Estudos Retrospectivos , Incidência
4.
Sci Rep ; 13(1): 7935, 2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37193817

RESUMO

This study aimed to compare the optic nerve head (ONH) structure in acute angle-closure glaucoma (AACG) and open-angle glaucoma (OAG) to investigate the differences in glaucomatous damage. The AACG and OAG eyes were matched with regard to global retinal nerve fiber layer thickness (RNFLT). AACG eyes were divided into two subgroups based on the presence of ONH swelling at the onset of AACG. RNFLT, Bruch's membrane opening-minimum rim width (BMO-MRW), and Bruch's membrane opening-minimum rim area (BMO-MRA) were analyzed. Global RNFLT values were similar in AACG and OAG groups, but lower than in the healthy group (P < 0.001). The global BMO-MRW and total BMO-MRA were significantly higher in AACG than in OAG group (P < 0.001, respectively). AACG showed similar global BMO-MRW and total BMO-MRA, irrespective of the presence or absence of ONH swelling, while AACG with ONH swelling was associated with significantly thinner global RNFLT compared to AACG without ONH swelling (P < 0.006). The result of differences in ONH structure between the OAG and AACG, especially the AACG with ONH swelling at the onset of AACG, suggests that the mechanisms of optic nerve damage in the two diseases are different.


Assuntos
Glaucoma de Ângulo Fechado , Glaucoma de Ângulo Aberto , Disco Óptico , Humanos , Pressão Intraocular , Células Ganglionares da Retina , Campos Visuais , Tomografia de Coerência Óptica , Fibras Nervosas , Lâmina Basilar da Corioide
5.
PLoS One ; 18(5): e0286007, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37200340

RESUMO

PURPOSE: Post-acute non-arteritic ischemic optic neuropathy (NAION) and glaucomatous optic neuropathy (GON) can be difficult to differentiate clinically. Our objective was to identify optical coherence tomography (OCT) parameters to help differentiate these optic neuropathies. METHODS: We compared 12 eyes of 8 patients with NAION and 12 eyes of 12 patients with GON, matched for age and visual field mean deviation (MD). All patients underwent clinical assessment, automated perimetry (Humphrey Field Analyzer II; Carl Zeiss Meditec, Dublin, CA, USA), and OCT imaging (Spectralis OCT2; Heidelberg Engineering, Heidelberg, Germany) of the optic nerve head and macula. We derived the neuroretinal minimum rim width (MRW), peripapillary retinal nerve fibre layer (RNFL) thickness, central anterior lamina cribrosa depth, and macular retinal thickness. RESULTS: MRW was markedly thicker, both globally and in all sectors, in the NAION group compared to the GON group. There was no significant group difference in RFNL thickness, globally or in any sector, with the exception of the temporal sector that was thinner in the NAION group. The group difference in MRW increased with increasing visual field loss. Other differences observed included lamina cribrosa depth significantly greater in the GON group and significantly thinner central macular retinal layers in the NAION group. The ganglion cell layer was not significantly different between the groups. CONCLUSIONS: The neuroretinal rim is altered in a dissimilar manner in NAION and GON and MRW is a clinically useful index for differentiating these two neuropathies. The fact that the difference in MRW between the two groups increased with disease severity suggests distinct remodelling patterns in response to differing insults with NAION and GON.


Assuntos
Glaucoma , Disco Óptico , Doenças do Nervo Óptico , Neuropatia Óptica Isquêmica , Humanos , Disco Óptico/diagnóstico por imagem , Neuropatia Óptica Isquêmica/diagnóstico por imagem , Células Ganglionares da Retina , Glaucoma/diagnóstico por imagem , Tomografia de Coerência Óptica/métodos , Gravidade do Paciente
6.
Indian J Ophthalmol ; 71(5): 2324, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37203011

RESUMO

Background: Optic disc anomalies with abnormal tissue on the disc surface includes, myelinated nerve fiber, optic disc drusen, and Bergmeister papillae. Imaging the radial peripapillary capillary (RPC) network in optic disc anomalies with optical coherence tomography-angiography (OCTA) can give information on the RPC network in these conditions. Purpose: This video describes the OCTA of optic nerve head and RPC network using the angio disc mode in cases of optic disc anomalies with abnormal tissue on the disc surface. Synopsis: This video presents characteristic features of RPC network in one eye each of myelinated nerve fiber, optic disc drusen, and Bergmeister papillae. Highlights: OCTA in optic disc anomalies with abnormal tissue on the disc surface show a dense RPC microvascular network. OCTA is an effective imaging modality to study vascular plexus/RPC and their alteration in these disc anomalies. Video link: https://youtu.be/zlflgijy56c.


Assuntos
Anormalidades do Olho , Drusas do Disco Óptico , Disco Óptico , Vítreo Primário Hiperplásico Persistente , Humanos , Disco Óptico/irrigação sanguínea , Angiofluoresceinografia/métodos , Microvasos , Anormalidades do Olho/complicações , Anormalidades do Olho/diagnóstico , Tomografia de Coerência Óptica/métodos , Vasos Retinianos
7.
BMC Ophthalmol ; 23(1): 208, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37165324

RESUMO

PURPOSE: To investigate morphological and microcirculation changes of optic nerve head (ONH) in simple high myopia (SHM) and pathologic myopia(PM) to evaluate and identify ONH changes in the development of PM. METHODS: A cross-sectional clinical study was used. Medical records from 193 right eyes of 193 patients with high myopia (HM) were included. Using the Topocon swept source optical coherence tomograph (SS-OCT) and fundus camera to detect the parameters, we have assessed the relative position and size of ONH, tilt and rotation of ONH, angle α (Defined as between retinal temporal arterial vascular arcades was measured from the centre of ONH with 250 pixels' radius), size and type of peripapillary atrophy (PPA), the thickness of peripapillary retinal nerve fiber layer (PRNFL), peripapillary choriodal thickness (PCT) and peripapillary scleral thickness (PST), and peripapillary vessel density (PVD). In addition, subjects were grouped as SHM and PM according to retinopathy, and the above parameters were compared between the two groups. RESULTS: Patients were divided into the SHM group (138 eyes) and the PM group (55 eyes). Paramters like older age, higher diopter and longer axial length (AL) of the PM were compared to SHM (t=-3.585, -8.808, -11.409, all P<0.05). There were no differences in the smallest diameter and area of ONH, rotation angle and ratio, or PST (all P>0.05). The angle α in PM was smaller than that in SHM (t = 2.728, P<0.01). The disc-fovea distance (DFD), the largest diameter, tilt index and ratio, PPA area and radian in PM were larger than in SHM (t=-3.962, Z=-2.525, t=-2.229, Z=-4.303, Z=-2.834, all P<0.05). The superior and inferior PRNFLs in PM were smaller than in SHM (t = 4.172, 4.263, all P<0.01). The temporoinferior PRNFL was the opposite (t=-2.421, P<0.01). The average PCT in PM (93.82 ± 29.96 µm) was smaller than in SHM (108.75 ± 30.70 µm) (P<0.05). The PVD in each direction of PM was smaller than that in SHM (t = 6.398, 4.196, 4.971, 3.267, 5.029, 5.653, 4.202, 5.146, 2.090, all P<0.05). CONCLUSION: Compared with SHM, the PM patients were older, with higher diopter. Their AL and DFD were longer, the angle α was smaller, the tilt index was more extensive, the PPA area and radian were larger, PCT was generally thinner, and PVD was lower. When the PPA area was bigger than the ONH area, this already indicated the presence of PM. Based on these results, we suggest ophthalmologists and myopia patients pay more attention to ONH's morphology and microcirculation changes as there is a possibility that microcirculatory changes precede morphologic changes.


Assuntos
Miopia , Disco Óptico , Humanos , Disco Óptico/patologia , Microcirculação , Estudos Transversais , Miopia/diagnóstico , Tomografia de Coerência Óptica/métodos
8.
Sci Rep ; 13(1): 7190, 2023 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-37137927

RESUMO

Identifying the clinical relevance of superficial versus deep layer macular vessel density (mVD) in glaucoma is important for monitoring glaucoma patients. Our current retrospective longitudinal study investigated the association of superficial and deep layer mVD parameters with glaucomatous visual field (VF) progression in mild to moderate open-angle glaucoma (OAG) eyes with central visual field (CVF) damage. Serial optical coherence tomography (OCT) angiography-derived mVD measurements were obtained in 182 mild to moderate OAG eyes (mean deviation ≥ -10 decibels). Forty-eight eyes (26.4%) showed VF progression during a mean follow-up of 3.5 years. The parafoveal and perifoveal mVDs of both superficial and deep layers showed significantly faster reduction rates in the VF progressors than in the non-progressors according to linear mixed effects models (P < 0.05). Cox and linear regression analyses showed that greater reduction rates of both the superficial layer parafoveal and perifoveal mVDs, but not their deep layer counterparts, were significant predictors of VF progression and faster VF loss (P < 0.05). In conclusion, faster rates of change in superficial but not deep layer mVD parameters are significantly associated with subsequent VF progression and faster VF deterioration in mild to moderate OAG eyes with CVF damage.


Assuntos
Glaucoma de Ângulo Aberto , Glaucoma , Disco Óptico , Humanos , Campos Visuais , Estudos Longitudinais , Estudos Retrospectivos , Pressão Intraocular , Vasos Retinianos/diagnóstico por imagem , Testes de Campo Visual , Tomografia de Coerência Óptica/métodos
9.
PLoS One ; 18(5): e0284743, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37146019

RESUMO

The paper presents a comparative study of the pulsatile attenuation amplitude (PAA) within the optic nerve head (ONH) at four different areas calculated from retinal video sequences and its relevance to the retinal nerve fiber layer thickness (RNFL) changes in normal subjects and patients with different stages of glaucoma. The proposed methodology utilizes processing of retinal video sequences acquired by a novel video ophthalmoscope. The PAA parameter measures the amplitude of heartbeat-modulated light attenuation in retinal tissue. Correlation analysis between PAA and RNFL is performed in vessel-free locations of the peripapillary region with the proposed evaluating patterns: 360° circular area, temporal semi-circle, nasal semi-circle. For comparison, the full ONH area is also included. Various positions and sizes of evaluating patterns in peripapillary region were tested which resulted in different outputs of correlation analysis. The results show significant correlation between PAA and RNFL thickness calculated in proposed areas. The highest correlation coefficient Rtemp = 0.557 (p<0.001) reflects the highest PAA-RNFL correspondence in the temporal semi-circular area, compared to the lowest value in the nasal semi-circular area (Rnasal = 0.332, p<0.001). Furthermore, the results indicate the most relevant approach to calculate PAA from the acquired video sequences is using a thin annulus near the ONH center. Finally, the paper shows the proposed photoplethysmographic principle based on innovative video ophthalmoscope can be used to analyze changes in retinal perfusion in peripapillary area and can be potentially used to assess progression of the RNFL deterioration.


Assuntos
Glaucoma , Disco Óptico , Humanos , Fibras Nervosas , Células Ganglionares da Retina , Glaucoma/diagnóstico , Tomografia de Coerência Óptica/métodos
10.
Klin Monbl Augenheilkd ; 240(4): 499-501, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37164393

RESUMO

BACKGROUND: Morning glory optic disc anomaly (MGODA) is a rare congenital defect of the optic nerve head. The optic nerve is enlarged, and its conical excavation is filled with glial tissue. It may be associated with cerebral malformations and ocular complications, whereas serous retinal detachment occurs in 38% of affected patients. Surgical treatment of detachment showed poor visual outcome in the past and conservative treatment options are scarce. CASE: A woman with MGODA presented in our clinic with sudden vision loss due to serous retinal detachment. She denied any previous ophthalmological problems and her past medical history was unremarkable. Vision testing showed normal visual acuity in her left eye and finger counting in her right eye. Slit lamp examination was unremarkable. Fundus examination of the right eye showed retinal detachment without holes or traction membranes and an enlarged optic disc with raised peripapillary tissue and glial tissue in the center of the optic disc. Due to the pathognomonic otpic disc finding, we diagnosed MGODA complicated by a serous retinal detachment. We treated the patient with systemic carboanhydrase inhibitors and documented the initial clinical findings as well as the course of disease under treatment by optical coherent tomography (OCT), fundus autofluorescence imaging (FAF), and visual field testing. During follow-up, we detected noticeable subretinal fluid regression and improvement in visual acuity. CONCLUSION: The application of oral carboanhydrase inhibitors appears to be a valid therapeutic option in patients with MGODA-associated serous macular detachment. OCT and FAF imaging are useful modalities for documentation of subretinal fluid regression and structural changes in the peripapillary region.


Assuntos
Disco Óptico , Descolamento Retiniano , Humanos , Feminino , Disco Óptico/diagnóstico por imagem , Disco Óptico/anormalidades , Descolamento Retiniano/complicações , Descolamento Retiniano/diagnóstico , Descolamento Retiniano/tratamento farmacológico , Nervo Óptico/anormalidades , Fundo de Olho , Tomografia de Coerência Óptica/métodos
11.
Klin Monbl Augenheilkd ; 240(4): 472-477, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37164405

RESUMO

PURPOSE: Detecting glaucoma damage progression is an essential component of follow-ups in glaucoma patients. It is still unclear which of the currently available and routinely used parameters of glaucoma damage heralds the loss of retinal ganglion cells first. We analysed local hospital data on primary open-angle glaucoma (POAG) patients and looked for correlations between the optical coherence tomography (OCT) structural, OCT angiography (OCTA), and visual field (VF) parameters. PATIENTS AND METHODS: Results of eye examinations of POAG patients at baseline, 6 months, and 12 months were analysed. Inclusion criteria were, apart from the diagnosis of POAG, availability and quality of all modalities of examination data and no surgical intervention on the eyes during the observation period. Data on VF mean defect (MD), OCT peripapillary nerve fibre layer (RNFL), OCT macular ganglion cell layer, and OCTA, peripapillary and in the macula, were parameters of interest. Correlations of structural (OCT and OCTA) on one, and functional parameters (VF MD) on the other side, at baseline and as changing over time (first 6 months vs. second 6 months) were performed. RESULTS: All together, data from 78 eyes of 78 POAG patients were included in the analysis. Correlations at baseline were all highly significant (Spearman's r-coefficients between 0.31 and 0.8, all p < 0.05). None of the correlations of parameter changes over time were significant (all p > 0.05). CONCLUSION: Whereas a robust correlation was observed at baseline between the structural (OCT and OCTA) and functional (VF MD) parameters, none of the examination modality could predict a change in the other modalities during the 1-year period. Results confirm the necessity of regularly performing both the structural and functional examinations in our glaucoma patients.


Assuntos
Glaucoma de Ângulo Aberto , Disco Óptico , Humanos , Glaucoma de Ângulo Aberto/diagnóstico , Disco Óptico/diagnóstico por imagem , Tomografia de Coerência Óptica/métodos , Estudos Retrospectivos , Prognóstico , Angiofluoresceinografia/métodos , Seguimentos , Pressão Intraocular
12.
Klin Monbl Augenheilkd ; 240(4): 608-612, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37164413

RESUMO

PURPOSE: To assess optic nerve head (ONH) and macular blood flow in young healthy volunteers using laser speckle flowgraphy (LSFG). METHODS: This is a prospective single-center study conducted at the Department of Ophthalmology, University Hospital Zurich from May to November 2021. Young, healthy men aged ≥ 18 years without ocular or systemic diseases were included. A corrected visual acuity (VA) of 0.0 logMAR or better in both eyes and an intraocular pressure (IOP) of 21 mmHg or lower were required for inclusion. Subjects exceeding a spherical equivalent (SE) of ± 6 diopters (dpt) were excluded. Blood flow in the macula and the ONH was recorded using the Nidek LSFG RetFlow device (Nidek Company, Ltd., Hirioshi-cho, Japan). Laser power was set to 0.5 Millivolts (mV). Mean blur rate (MBR) was recorded as a parameter for blood flow. MBR is a calculated parameter that represents relative blood flow velocity correlated with the real anatomical blood flow rate. Colored heat maps of the recorded retinal area were generated automatically by the RetFlow device. RESULTS: Final analyses included 83 eyes of 43 male volunteers. Mean age was 21.9 years (SD ± 1.5, range: 20 to 29). Mean corrected VA was - 0.1 logMAR (SD ± 0.05, range: - 0.2 to 0.0), mean IOP was 15.4 mmHg (SD ± 2.5, range: 8.5 to 18.5), and mean SE was - 0.3 dpt (SD ± 1.2, range: - 5.0 to 1.2). Mean ONH MBR was 37.44 (SD ± 7.9, range: 22.5 to 53.5) and mean macular MBR was 27.8 (SD ± 9.7, range: 6.4 to 57.7). Pearson's Test showed a strong correlation between macular and papillary blood flow (p < 0.05, coefficient: 0.647). CONCLUSION: This study provides both ONH and macular blood flow data in a healthy young male population, showing a strong correlation between ONH and macular blood flow in the examined eyes. Further investigations are required to assess the validity of MBR as a parameter for the combined evaluation of retinal blood flow at the macula and ONH in healthy volunteers and patients with various diseases.


Assuntos
Disco Óptico , Humanos , Masculino , Adulto Jovem , Adulto , Disco Óptico/diagnóstico por imagem , Disco Óptico/irrigação sanguínea , Voluntários Saudáveis , Estudos Prospectivos , Fluxo Sanguíneo Regional/fisiologia , Velocidade do Fluxo Sanguíneo/fisiologia , Lasers
15.
JAMA Ophthalmol ; 141(5): e230405, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-37199808

RESUMO

This case report discusses a diagnosis of 2 optic disc pits in an otherwise asymptomatic woman with high myopia.


Assuntos
Anormalidades do Olho , Miopia , Disco Óptico , Feminino , Humanos , Retina , Anormalidades do Olho/complicações , Anormalidades do Olho/diagnóstico , Miopia/complicações , Miopia/diagnóstico , Transtornos da Visão , Pigmentação , Tomografia de Coerência Óptica
16.
Invest Ophthalmol Vis Sci ; 64(6): 5, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-37126358

RESUMO

Purpose: To describe nonpathological myopia-related characteristics of the human eye. Methods: Based on histomorphometric and clinical studies, qualitative and quantitative findings associated with myopic axial elongation are presented. Results: In axial myopia, the eye changes from a spherical shape to a prolate ellipsoid, photoreceptor, and retinal pigment epithelium cell density and total retinal thickness decrease, most marked in the retroequatorial region, followed by the equator. The choroid and sclera are thin, most markedly at the posterior pole and least markedly at the ora serrata. The sclera undergoes alterations in fibroblast activity, changes in extracellular matrix content, and remodeling. Bruch's membrane (BM) thickness is unrelated to axial length, although the BM volume increases. In moderate myopia, the BM opening shifts, usually toward the fovea, leading to the BM overhanging into the nasal intrapapillary compartment. Subsequently, the BM is absent in the temporal region (such as parapapillary gamma zone), the optic disc takes on a vertically oval shape, the fovea-optic disc distance elongates without macular BM elongation, the angle kappa reduces, and the papillomacular retinal vessels and nerve fibers straighten and stretch. In high myopia, the BM opening and the optic disc enlarge, the lamina cribrosa, the peripapillary scleral flange (such as parapapillary delta zone) and the peripapillary choroidal border tissue lengthen and thin, and a circular gamma and delta zone develop. Conclusions: A thorough characterization of ocular changes in nonpathological myopia are of importance to better understand the mechanisms of myopic axial elongation, pathological structural changes, and psychophysical sequelae of myopia on visual function.


Assuntos
Miopia , Disco Óptico , Humanos , Comprimento Axial do Olho/patologia , Miopia/patologia , Disco Óptico/patologia , Corioide/patologia , Lâmina Basilar da Corioide/patologia
17.
Cells Dev ; 174: 203848, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37172718

RESUMO

The discovery and study of adult stem cells have revolutionized regenerative medicine by offering new opportunities for treating various medical conditions. Anamniote stem cells, which retain their full proliferative capacity and full differentiation range throughout their lifetime, harbour a greater potential compared to mammalian adult stem cells, which only exhibit limited stem cell potential. Therefore, understanding the mechanisms underlying these differences is of significant interest. In this review, we examine the similarities and differences of adult retinal stem cells in anamniotes and mammals, from their embryonic stages in the optic vesicle to their residence in the postembryonic retinal stem cell niche, the ciliary marginal zone located in the retinal periphery. In anamniotes, developing precursors of retinal stem cells are exposed to various environmental cues during their migration in the complex morphogenetic remodelling of the optic vesicle to the optic cup. In contrast, their mammalian counterparts in the retinal periphery are primarily instructed by neighbouring tissues once they are in place. We explore the distinct modes of optic cup morphogenesis in mammals and teleost fish and highlight molecular mechanisms governing morphogenesis and stem cells instruction. The review concludes with the molecular mechanisms of ciliary marginal zone formation and offers a perspective on the impact of comparative single cell transcriptomic studies to reveal the evolutionary similarities and differences.


Assuntos
Células-Tronco Adultas , Disco Óptico , Animais , Retina , Peixes , Desenvolvimento Embrionário , Mamíferos
18.
Invest Ophthalmol Vis Sci ; 64(5): 25, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37227745

RESUMO

Purpose: To search for histologic differences in the beta zone between myopic eyes versus eyes with secondary angle-closure glaucoma. Methods: The histomorphometric study consisted of human eyes enucleated due to uveal melanomas or secondary angle-closure glaucoma. Results: The study included 100 eyes (age: 62.1 ± 15.1 years; axial length: 25.6 ± 3.1 mm; range: 20.0-35.0 mm). In non-highly myopic glaucomatous eyes compared with non-highly myopic nonglaucomatous eyes, the parapapillary alpha zone was longer (223 ± 168 µm vs. 125 ± 128 µm; P = 0.03), beta zone prevalence (15/20 vs. 6/41; P < 0.001) and length (277 ± 245 µm vs. 44 ± 150 µm; P = 0.001) were higher, and RPE cell density in the alpha zone and alpha zone border was lower (all P < 0.05). In highly myopic nonglaucomatous eyes compared with non-highly myopic glaucomatous eyes, parapapillary RPE drusen prevalence (2/19 vs. 10/10; P = 0.01) and alpha zone prevalence (2/19 vs. 16/20; P < 0.001) and length (23 ± 68 µm vs. 223 ± 168 µm; P < 0.001) were lower. In non-highly myopic glaucomatous eyes, Bruch's membrane (BM) thickness decreased (P < 0.001) from the beta zone (6.0 ± 3.1 µm) to the alpha zone (5.1 ± 4.3 µm) and peripheral to it (3.0 ± 0.9 µm). In highly myopic nonglaucomatous eyes, BM thickness did not differ (P > 0.10) between all three regions. In the total study population, RPE cell density in the alpha zone (24.5 ± 9.3 cells/240 µm) was higher than at the alpha zone border (19.2 ± 4.8 cells/240 µm; P < 0.001) or peripheral to it (19.0 ± 3.6 cells/240 µm; P < 0.001). Conclusions: The glaucomatous beta zone in eyes with chronic angle-closure glaucoma (with the alpha zone, parapapillary RPE drusen, thickened BM, and higher RPE cell count in the adjacent alpha zone) differs histologically from the myopic beta zone (characterized by the absence of the alpha zone and parapapillary RPE drusen, unremarkable BM thickness, and unremarkable parapapillary RPE). The differences suggest different etiologies of the glaucomatous versus myopic beta zone.


Assuntos
Glaucoma de Ângulo Fechado , Glaucoma , Miopia , Disco Óptico , Humanos , Pessoa de Meia-Idade , Idoso , Glaucoma de Ângulo Fechado/patologia , Disco Óptico/patologia , Comprimento Axial do Olho/patologia , Glaucoma/patologia , Miopia/patologia
20.
Comput Biol Med ; 160: 106903, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37146494

RESUMO

Proper estimation of the cup-to-disc ratio (C/D ratio) plays a significant role in ophthalmic examinations, and it is urgent to improve the efficiency of C/D ratio automatic measurement. Therefore, we propose a new method for measuring the C/D ratio of OCTs in normal subjects. Firstly, the end-to-end deep convolution network is used to segment and detect the inner limiting membrane (ILM) and the two Bruch's membrane opening (BMO) terminations. Then, we introduce an ellipse fitting technique to post-process the edge of the optic disc. Finally, the proposed method is evaluated on 41 normal subjects using the optic-disc-area scanning mode of three machines: BV1000, Topcon 3D OCT-1, and Nidek ARK-1. In addition, pairwise correlation analyses are carried out to compare the C/D ratio measurement method of BV1000 to existing commercial OCT machines as well as other state-of-the-art methods. The correlation coefficient between the C/D ratio calculated by BV1000 and the C/D ratio calculated by manual annotation is 0.84, which indicates that the proposed method has a strong correlation with the results of manual annotation by ophthalmologists. Moreover, in comparison between BV1000, Topcon and Nidek in practical screening among normal subjects, the proportion of the C/D ratio less than 0.6 calculated by BV1000 accounts for 96.34%, which is the closest to the clinical statistics among the three OCT machines. The above experimental results and analysis show that the proposed method performs well in cup and disc detection and C/D ratio measurement, and compared with the existing commercial OCT equipment, the C/D ratio measurement results are relatively close to reality, which has certain clinical application value.


Assuntos
Disco Óptico , Tomografia de Coerência Óptica , Humanos , Tomografia de Coerência Óptica/métodos , Lâmina Basilar da Corioide
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