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1.
Can J Ophthalmol ; 58(2): 90-96, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-34687615

RESUMEN

OBJECTIVE: To evaluate the long-term structural and microvascular retinal effects of internal limiting membrane peeling for full-thickness macular hole (FTMH) using en face adaptive optics optical coherence tomography (AO-OCT), conventional OCT, and OCT angiography (OCTA). DESIGN: Interventional case series. PARTICIPANTS: Patients with FTMH treated with vitrectomy, internal limiting membrane peeling, and gas tamponade. METHODS: Eleven eyes with FTMH that had at least 12 months of postoperative follow-up were enrolled in the study. En face AO-OCT was used to image the superficial retina in the peeled and nonpeeled areas. En face structural OCT was performed to image the inner retinal dimples (IRDs), macular thickness, and retinal nerve fibre layer (RNFL). En face OCTA was used to examine the integrity of the peripapillary nerve fibre layer (NFL) plexus. RESULTS: AO-OCT showed RFNL wrapping around the IRDs, and no obvious peripapillary NFL plexus dropout was seen with OCTA. Scattered hyper-reflective dots were observed on the surface of the peeled retina in all patients imaged with AO-OCT. No significant differences were found in IRD number (91.5 ± 24.4 versus 77.2 ± 14.7; P = 2.07), IRD proportionate area (8.36 ± 3.34 versus 7.53 ± 2.60; P = 0.159), or macular thickness between the 6- and 12-month (or greater) postoperative visits. CONCLUSION: IRDs do not to progress beyond 6 months postoperatively, and no obvious damage to RFNL and peripapillary NFL plexus was detected. Hyper-reflective dots on the surface of the retina suggestive of possible Müller cell reactive gliosis were identified with AO-OCT.


Asunto(s)
Membrana Epirretinal , Perforaciones de la Retina , Humanos , Perforaciones de la Retina/diagnóstico , Perforaciones de la Retina/cirugía , Tomografía de Coherencia Óptica/métodos , Membrana Epirretinal/cirugía , Retina , Vitrectomía/métodos , Estudios Retrospectivos
2.
Invest Ophthalmol Vis Sci ; 61(5): 8, 2020 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-32392316

RESUMEN

Purpose: The purpose of this study was to compare perfusion parameters of the parafovea with scans outside the parafovea to find an area most susceptible to changes secondary to diabetic retinopathy (DR). Methods: Patients with different DR severity levels as well as controls were included in this cross-sectional clinical trial. Seven standardized 3 × 3 mm areas were recorded with Swept Source Optical Coherence Tomography Angiography: one centered on the fovea, three were temporal to the fovea, and three nasally to the optic disc. The capillary perfusion density (PD) of the superficial capillary complex (SCC) and deep capillary complex (DCC) as well as the fractal dimension (FD) were generated. Statistical analyses were done with R software. Results: One hundred ninety-two eyes (33 controls, 51 no-DR, 41 mild DR, 37 moderate/severe DR, and 30 proliferative DR), of which 105 patients with diabetes and 25 healthy controls were included (59 ± 15 years; 62 women). Mean PD of the DCC was significantly less in patients without DR (parafovea = 0.48 ± 0.03; temporal = 0.48 ± 0.02; and nasal = 0.48 ± 0.03) compared to controls (parafovea = 0.49 ± 0.02; temporal = 0.50 ± 0.02; and nasal = 0.50 ± 0.03). With increasing DR severity, PD and FD of the SCC and DCC further decreased. Conclusions: Capillary perfusion of the retina is affected early by diabetes. PD of the DCC was significantly reduced in patients with diabetes who did not have any clinical signs of DR. The capillary network outside the parafovea was more susceptible to capillary perfusion deficits compared to the capillaries close to the fovea. Trial Registration: clinicaltrial.gov, NCT03765112, https://clinicaltrials.gov/ct2/show/NCT03765112?term=NCT03765112&rank=1.


Asunto(s)
Retinopatía Diabética/diagnóstico por imagen , Angiografía con Fluoresceína , Retina/diagnóstico por imagen , Tomografía de Coherencia Óptica , Capilares/diagnóstico por imagen , Estudios Transversales , Retinopatía Diabética/fisiopatología , Femenino , Fóvea Central/irrigación sanguínea , Fóvea Central/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Retina/fisiopatología , Vasos Retinianos/diagnóstico por imagen
3.
Retina ; 40(3): 557-566, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30664124

RESUMEN

PURPOSE: To quantitatively and qualitatively evaluate the microvascular and structural abnormalities associated with inner retinal dimpling after internal limiting membrane peeling for full-thickness macular holes using sequential en face optical coherence tomography (OCT) and OCT angiography. METHODS: Thirteen eyes of 13 patients with idiopathic full-thickness macular holes were enrolled in the study. Patients were treated with pars plana vitrectomy, internal limiting membrane peeling, and gas tamponade. Subjects were evaluated preoperatively and at postoperative Months 1, 3, and 6. At each visit, patients underwent a comprehensive ophthalmologic examination, en face OCT and OCT angiography. The morphology and number and proportionate area of inner retinal dimples were analyzed. Vessel density of the superficial vascular complex at all visits was also measured. RESULTS: Inner retinal dimples were identified 1 month after surgery in all cases. The number and proportionate area of inner retinal dimples significantly increased over the follow-up period (P = 0.05). Preoperative vessel density of the superficial vascular complex was 17.9 ± 1.9 and did not change significantly over the follow-up period (P = 0.15). CONCLUSION: Inner retinal dimples are identified with en face OCT as early as the first month after internal limiting membrane peeling for idiopathic full-thickness macular holes and progressively increase in number and proportionate area in the subsequent 3 to 6 months after surgery. This may be the result of progressive deturgescence of the nerve fiber layer in the postoperative period.


Asunto(s)
Membrana Basal/cirugía , Angiografía con Fluoresceína/métodos , Mácula Lútea/patología , Células Ganglionares de la Retina/patología , Perforaciones de la Retina/cirugía , Tomografía de Coherencia Óptica/métodos , Vitrectomía/métodos , Anciano , Femenino , Estudios de Seguimiento , Fondo de Ojo , Humanos , Masculino , Perforaciones de la Retina/diagnóstico , Estudios Retrospectivos , Agudeza Visual
4.
Hum Mol Genet ; 28(14): 2395-2414, 2019 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-31032853

RESUMEN

Heterozygous missense mutations in several genes in the WNT5A signaling pathway cause autosomal dominant Robinow syndrome 1 (DRS1). Our objective was to clarify the functional impact of a missense mutation in WNT5A on the skeleton, one of the main affected tissues in RS. We delivered avian replication competent retroviruses (RCAS) containing human wild-type WNT5A (wtWNT5A), WNT5AC83S variant or GFP/AlkPO4 control genes to the chicken embryo limb. Strikingly, WNT5AC83S consistently caused a delay in ossification and bones were more than 50% shorter and 200% wider than controls. In contrast, bone dimensions in wtWNT5A limbs were slightly affected (20% shorter, 25% wider) but ossification occurred on schedule. The dysmorphology of bones was established during cartilage differentiation. Instead of stereotypical stacking of chondrocytes, the WNT5AC83S-infected cartilage was composed of randomly oriented chondrocytes and that had diffuse, rather than concentrated Prickle staining, both signs of disrupted planar cell polarity (PCP) mechanisms. Biochemical assays revealed that C83S variant was able to activate the Jun N-terminal kinase-PCP pathway similar to wtWNT5A; however, the activity of the variant ligand was influenced by receptor availability. Unexpectedly, the C83S change caused a reduction in the amount of protein being synthesized and secreted, compared to wtWNT5A. Thus, in the chicken and human, RS phenotypes are produced from the C83S mutation, even though the variant protein is less abundant than wtWNT5A. We conclude the variant protein has dominant-negative effects on chondrogenesis leading to limb abnormalities.


Asunto(s)
Condrocitos/citología , Condrogénesis , Anomalías Craneofaciales/metabolismo , Enanismo/metabolismo , Extremidades/embriología , Deformidades Congénitas de las Extremidades/metabolismo , Anomalías Urogenitales/metabolismo , Proteína Wnt-5a/genética , Animales , Animales Modificados Genéticamente , Cartílago/metabolismo , Polaridad Celular/fisiología , Embrión de Pollo , Pollos , Condrogénesis/genética , Anomalías Craneofaciales/genética , Modelos Animales de Enfermedad , Enanismo/genética , Células HEK293 , Humanos , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Deformidades Congénitas de las Extremidades/genética , Mutación Missense , Fenotipo , Anomalías Urogenitales/genética , Vía de Señalización Wnt , Proteína Wnt-5a/metabolismo
5.
Biomed Opt Express ; 9(11): 5353-5367, 2018 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-30460133

RESUMEN

Automated measurements of the human cone mosaic requires the identification of individual cone photoreceptors. The current gold standard, manual labeling, is a tedious process and can not be done in a clinically useful timeframe. As such, we present an automated algorithm for identifying cone photoreceptors in adaptive optics optical coherence tomography (AO-OCT) images. Our approach fine-tunes a pre-trained convolutional neural network originally trained on AO scanning laser ophthalmoscope (AO-SLO) images, to work on previously unseen data from a different imaging modality. On average, the automated method correctly identified 94% of manually labeled cones when compared to manual raters, from twenty different AO-OCT images acquired from five normal subjects. Voronoi analysis confirmed the general hexagonal-packing structure of the cone mosaic as well as the general cone density variability across portions of the retina. The consistency of our measurements demonstrates the high reliability and practical utility of having an automated solution to this problem.

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