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1.
Retina ; 41(11): 2361-2369, 2021 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-33840784

RESUMEN

PURPOSE: Stellate nonhereditary idiopathic foveomacular retinoschisis is a disorder characterized by splitting of the retina at the macula, without a known underlying mechanical or inherited cause. This study investigates demographic, anatomical, and functional characteristics of subjects with stellate nonhereditary idiopathic foveomacular retinoschisis, to explore potential underlying mechanisms. METHODS: In this single-site, retrospective, and cross-sectional, observational study, data were collected from 28 eyes from 24 subjects with stellate nonhereditary idiopathic foveomacular retinoschisis. Descriptive statistics were reported, based on the observed anatomico-functional features. RESULTS: The visual acuity remained stable (median 20/20) in all subjects over a median follow-up of 17 months. All cases demonstrated foveomacular retinoschisis within Henle's fiber layer, at the junction of the outer plexiform and outer nuclear layers. This schisis cavity extended beyond the limits of the macular OCT temporally in all eyes. In most affected eyes, there were documented features of peripheral retinoschisis and broad attachment of the posterior hyaloid at the macula. Functional testing in a cross-sectional subset demonstrated normal retinal sensitivity centrally but an absolute scotoma peripherally. CONCLUSION: Stellate nonhereditary idiopathic foveomacular retinoschisis seems to be associated with peripheral retinoschisis and anomalous or incomplete posterior hyaloid detachment. Despite chronic manifestation, this does not significantly affect central visual function but can manifest with profound loss of peripheral visual function.


Asunto(s)
Angiografía con Fluoresceína/métodos , Fóvea Central/diagnóstico por imagen , Desprendimiento de Retina/etiología , Retinosquisis/diagnóstico , Tomografía de Coherencia Óptica/métodos , Agudeza Visual , Adulto , Anciano , Anciano de 80 o más Años , Estudios Transversales , Femenino , Estudios de Seguimiento , Fondo de Ojo , Humanos , Masculino , Persona de Mediana Edad , Desprendimiento de Retina/diagnóstico , Retinosquisis/complicaciones , Estudios Retrospectivos , Factores de Tiempo
2.
Diagnostics (Basel) ; 14(10)2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38786303

RESUMEN

(1) Background: We reviewed a stem cell-derived therapeutic strategy for advanced neovascular age-related macular degeneration (nAMD) using a human embryonic stem cell-derived retinal pigment epithelium (hESC-RPE) monolayer delivered on a coated, synthetic basement membrane (BM)-the patch-and assessed the presence and distribution of hESC-RPE over 5 years following transplantation, as well as functional outcomes. (2) Methods: Two subjects with acute vision loss due to sub-macular haemorrhage in advanced nAMD received the hESC-RPE patch. Systematic immunosuppression was used peri-operatively followed by local depot immunosuppression. The subjects were monitored for five years with observation of RPE patch pigmentation, extension beyond the patch boundary into surrounding retina, thickness of hESC-RPE and synthetic BM and review for migration and proliferation of hESC-RPE. Visual function was also assessed. (3) Results: The two study participants showed clear RPE characteristics of the patch, preservation of some retinal ultrastructure with signs of remodelling, fibrosis and thinning on optical coherence tomography over the 5-year period. For both participants, there was evidence of pigment extension beyond the patch continuing until 12 months post-operatively, which stabilised and was preserved until 5 years post-operatively. Measurement of hESC-RPE and BM thickness over time for both cases were consistent with predefined histological measurements of these two layers. There was no evidence of distant RPE migration or proliferation in either case beyond the monolayer. Sustained visual acuity improvement was apparent for 2 years in both subjects, with one subject maintaining the improvement for 5 years. Both subjects demonstrated initial improvement in fixation and microperimetry compared to baseline, at year 1, although only one maintained this at 4 years post-intervention. (4) Conclusions: hESC-RPE patches show evidence of continued pigmentation, with extension, to cover bare host basement membrane for up to 5 years post-implantation. There is evidence that this represents functional RPE on the patch and at the patch border where host RPE is absent. The measurements for thickness of hESC-RPE and BM suggest persistence of both layers at 5 years. No safety concerns were raised for the hypothetical risk of RPE migration, proliferation or tumour formation. Visual function also showed sustained improvement for 2 years in one subject and 5 years in the other subject.

3.
Semin Ophthalmol ; 39(1): 96-101, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37539994

RESUMEN

PURPOSE: To evaluate the efficacy and safety of intravitreal aflibercept injections for diabetic macular edema (DME) treatment in a tertiary referral center in Greece. METHODS: ADMIRE was a prospective, observational cohort study of patients with DME. Efficacy was assessed by change in best-corrected visual acuity (BCVA) and central subfield thickness (CST) from baseline to month 36 after treatment with intravitreal aflibercept in treatment-naive patients and previously treated patients. Safety was evaluated by recording any patients-reported events. RESULTS: Participants in the study were 94 patients with DME, 70 treatment naive and 24 previously treated with ranibizumab. At month 36 of the follow-up period, the mean change in BCVA was +7.4 letters compared to baseline (p < .001). The mean change in BCVA in treatment-naive patients was +8.9 letters and differed significantly compared to previously treated patients (+5.9 letters, p = .041). In addition, patients who received a loading dose of 5 monthly injections at the initiation of treatment provided better VA outcomes (+11.4 vs. +6.1 letters, p < .001). Accordingly, the mean CST at month 36 (369.6 ± 72.8 µm) was significantly decreased compared to baseline (479.2 ± 68.3 µm, p < .001). Overall, the mean number of injections at month 36 was 13.4. Safety analysis showed that the reported ocular adverse events during the 36-month study period were mild and not sight-threatening. CONCLUSION: Intravitreal aflibercept was found to be safe and effective for the treatment of DME in real-life in a Greek population. Treatment-naive patients and those who received a loading dose of five consecutive monthly injections at initiation of treatment exhibited better outcomes, suggesting that early and effective treatment may prevent vision loss.


Asunto(s)
Diabetes Mellitus , Retinopatía Diabética , Edema Macular , Humanos , Edema Macular/diagnóstico , Edema Macular/tratamiento farmacológico , Retinopatía Diabética/complicaciones , Retinopatía Diabética/tratamiento farmacológico , Grecia/epidemiología , Inhibidores de la Angiogénesis , Estudios Prospectivos , Agudeza Visual , Ranibizumab , Receptores de Factores de Crecimiento Endotelial Vascular/uso terapéutico , Proteínas Recombinantes de Fusión/uso terapéutico , Resultado del Tratamiento , Inyecciones Intravítreas
4.
Front Neurosci ; 15: 729807, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34690675

RESUMEN

Color vision is considered a marker of cone function and its assessment in patients with retinal pathology is complementary to the assessments of spatial vision [best-corrected visual acuity (BCVA)] and contrast detection (perimetry). Rod-cone and chorioretinal dystrophies-such as choroideremia-typically cause alterations to color vision, making its assessment a potential outcome measure in clinical trials. However, clinical evaluation of color vision may be compromised by pathological changes to spatial vision and the visual field. The low vision Cambridge Color Test (lvCCT) was developed specifically to address these latter issues. We used the trivector version of the lvCCT to quantify color discrimination in a cohort of 53 patients with choroideremia. This test enables rapid and precise characterization of color discrimination along protan, deutan, and tritan axes more reliably than the historically preferred test for clinical trials, namely the Farnsworth Munsell 100 Hue test. The lvCCT demonstrates that color vision defects-particularly along the tritan axis-are seen early in choroideremia, and that this occurs independent of changes in visual acuity, pattern electroretinography and ellipsoid zone area on optical coherence tomography (OCT). We argue that the selective loss of tritan color discrimination can be explained by our current understanding of the machinery of color vision and the pathophysiology of choroideremia.

5.
Biomed Opt Express ; 11(5): 2490-2510, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32499939

RESUMEN

This paper addresses retinal vessel segmentation on optical coherence tomography angiography (OCT-A) images of the human retina. Our approach is motivated by the need for high precision image-guided delivery of regenerative therapies in vitreo-retinal surgery. OCT-A visualizes macular vasculature, the main landmark of the surgically targeted area, at a level of detail and spatial extent unattainable by other imaging modalities. Thus, automatic extraction of detailed vessel maps can ultimately inform surgical planning. We address the task of delineation of the Superficial Vascular Plexus in 2D Maximum Intensity Projections (MIP) of OCT-A using convolutional neural networks that iteratively refine the quality of the produced vessel segmentations. We demonstrate that the proposed approach compares favourably to alternative network baselines and graph-based methodologies through extensive experimental analysis, using data collected from 50 subjects, including both individuals that underwent surgery for structural macular abnormalities and healthy subjects. Additionally, we demonstrate generalization to 3D segmentation and narrower field-of-view OCT-A. In the future, the extracted vessel maps will be leveraged for surgical planning and semi-automated intraoperative navigation in vitreo-retinal surgery.

6.
Am J Ophthalmol ; 207: 159-169, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31095956

RESUMEN

PURPOSE: To investigate the natural history of optic disc pit maculopathy and explore the associations between demographic, anatomic, and functional characteristics. DESIGN: Retrospective, comparative case series. METHODS: This was a single-center medical record review of previously untreated optic disc pit maculopathy. Baseline data of visual function, demographics, and pit physiognomy were collected, and further subgroup analysis was undertaken on patients with long-term follow-up, according to whether they were monitored or received surgical intervention. LogMAR visual acuity was the primary outcome measure, and anatomic characteristics were reported where available. RESULTS: Eighty-seven patients were identified with a new presentation of optic disc pit maculopathy. No demographic or pit features were correlated with vision at baseline. In 51 patients with available optical coherence tomography data, only the presence of subretinal fluid at baseline was associated with poorer visual acuity (P < .001). Fifty-two patients who were monitored without treatment had available long-term follow-up data. The mean change in visual acuity in this group was 0.01, with 77% maintaining visual acuity ≤0.30. Twenty-seven patients underwent surgery and showed significant postoperative improvement in vision (P < .001), with 59% achieving an acuity ≤0.30. Duration of postoperative follow-up was associated with better visual acuity (P = .007). CONCLUSION: Many patients with optic disc pit maculopathy maintain good long-term visual acuity and may demonstrate resolution of subretinal fluid in the absence of surgical intervention. There may be evidence to support delaying surgical treatment until visual deterioration is observed because of the potential stability or spontaneous improvement of the condition, the high rate of reoperation, and the long-term positive outcomes of deferred intervention.


Asunto(s)
Mácula Lútea/patología , Degeneración Macular/etiología , Disco Óptico/anomalías , Enfermedades del Nervio Óptico/complicaciones , Tomografía de Coherencia Óptica/métodos , Agudeza Visual , Adulto , Femenino , Estudios de Seguimiento , Humanos , Degeneración Macular/diagnóstico , Degeneración Macular/fisiopatología , Masculino , Disco Óptico/patología , Enfermedades del Nervio Óptico/congénito , Enfermedades del Nervio Óptico/diagnóstico , Pronóstico , Estudios Retrospectivos
9.
Nat Biotechnol ; 36(4): 328-337, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29553577

RESUMEN

Age-related macular degeneration (AMD) remains a major cause of blindness, with dysfunction and loss of retinal pigment epithelium (RPE) central to disease progression. We engineered an RPE patch comprising a fully differentiated, human embryonic stem cell (hESC)-derived RPE monolayer on a coated, synthetic basement membrane. We delivered the patch, using a purpose-designed microsurgical tool, into the subretinal space of one eye in each of two patients with severe exudative AMD. Primary endpoints were incidence and severity of adverse events and proportion of subjects with improved best-corrected visual acuity of 15 letters or more. We report successful delivery and survival of the RPE patch by biomicroscopy and optical coherence tomography, and a visual acuity gain of 29 and 21 letters in the two patients, respectively, over 12 months. Only local immunosuppression was used long-term. We also present the preclinical surgical, cell safety and tumorigenicity studies leading to trial approval. This work supports the feasibility and safety of hESC-RPE patch transplantation as a regenerative strategy for AMD.


Asunto(s)
Células Madre Embrionarias Humanas/trasplante , Degeneración Macular/terapia , Epitelio Pigmentado de la Retina/trasplante , Agudeza Visual/fisiología , Anciano , Animales , Membrana Basal/diagnóstico por imagen , Membrana Basal/crecimiento & desarrollo , Diferenciación Celular/genética , Femenino , Humanos , Degeneración Macular/diagnóstico por imagen , Degeneración Macular/patología , Masculino , Ratones , Persona de Mediana Edad , Epitelio Pigmentado de la Retina/diagnóstico por imagen , Epitelio Pigmentado de la Retina/crecimiento & desarrollo , Trasplante de Células Madre/efectos adversos , Porcinos , Tomografía de Coherencia Óptica
10.
Case Rep Ophthalmol ; 5(2): 231-8, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-25232335

RESUMEN

PURPOSE: To present the case of a patient with bilateral hypertensive retinopathy complicated with retinal neovascularization who received anti-VEGF intravitreal injection in one eye and panretinal photocoagulation (PRP) in the fellow eye. METHODS: A 33-year-old male patient presented with gradual visual loss in both eyes for the last 5 months. At that time, he was examined by an ophthalmologist and occlusive retinopathy due to malignant systematic hypertension was diagnosed. He was put on antihypertensive treatment but no ophthalmic treatment was undertaken. At presentation, 5 months later, best-corrected visual acuity (BCVA) was 0.1 in the right eye (RE) and 0.9 in the left eye (LE). Fundus examination was compatible with hypertensive retinopathy complicated with retinal neovascularization. Fluorescein angiography (FFA) revealed macular ischemia mainly in the RE and large areas of peripheral retinal ischemia and neovascularization with vascular leakage in both eyes. The patient was treated with two anti-VEGF (ranibizumab) injections with 2 months interval in the RE and PRP laser in the LE. RESULTS: Follow-up examination after 12 months showed mild improvement in BCVA, and FFA documented regression of retinal neovascularization in both eyes. CONCLUSION: Hypertensive retinopathy can be rarely complicated with retinal neovascularization. Treatment with PRP can be undertaken. In our case, the use of an intravitreal anti-VEGF agent seemed to halt its progression satisfactorily.

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