Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 712
Filtrar
1.
Ann Med ; 56(1): 2397573, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39233610

RESUMEN

PURPOSE: To evaluate the findings and the correlation of optical coherence tomography angiography and pattern and flash electroretinography in diabetes mellitus without retinopathy. METHODS: Seventy-six eyes of 38 diabetic patients and age- and gender-matched control subjects were included in the study. The foveal avascular zone (FAZ), whole, foveal, parafoveal and perifoveal vascular densities of the superficial capillary plexus (SCP), deep capillary plexus (DCP) and choriocapillary plexus (CCP) layers were analyzed using optical coherence tomography angiography (OCTA). The amplitudes and implicit times of P50 and N95 waves of the pattern ERG (pERG) and the amplitudes and implicit times of the scotopic and photopic b-waves and oscillatory potentials (OP) of the flash ERG (fERG) tests were evaluated using the Metrovision brand monpack model device. RESULTS: The mean age of the patients was 59.7 ± 7.9 [range 43-79] years. Eighteen (47%) of the patients were female and 20 (53%) were male. The mean duration of diabetes was 7.45 ± 6.2 [range 1-20] years. No significant difference in FAZ area was found between study subjects and controls. Vascular density (VD) values of the superficial capillary plexus (SCP) layer were significantly lower (whole VD, 44.7 ± 3.3 vs. 46.6 ± 3.2%, p = 0.01, foveal VD 16.8 ± 6.4 vs. 24.9 ± 6.1%, p < 0.01, parafoveal VD 45.6 ± 4.5 vs. 47.1 ± 4.4%, p = 0.27 and perifoveal VD 45.5 ± 3.3 vs. 47.3 ± 3.1%, p = 0.01, respectively) in the diabetic group except the parafoveal area. VD measurements in deep and choriocapillary plexuses did not significantly differ between the groups (p > 0.05). ERG tests revealed significantly lower scotopic b-wave amplitudes (130.2 ± 39.3 µV vs.163.3 ± 47.8 µV, p < 0.01) and photopic b-wave amplitudes (83.2 ± 20.7 µV vs. 99.6 ± 29.4 µV, p < 0.01) in the diabetic patients. The implicit time of the photopic responses was significantly prolonged (28.9 ± 1.3 ms vs. 27.8 ± 2.1 ms, p = 0.01) in the patients. Oscillatory potentials in all components consisting of O1 to O4 and the sum of the OP potentials were lower in the diabetic group than the control subjects (p < 0.001). The P50 and N95 amplitudes and implicit times were comparable between the groups (p > 0.05). Correlation analysis showed a positive correlation between N95 amplitudes in pERG and the superficial vessel densities in OCTA (r = 0.26, p = 0.04). A negative correlation was found between photopic implicit times in fERG and the choriocapillary vessel densities (r=-0.27, p = 0.03). CONCLUSION: OCTA revealed decreased superficial vascular densities with the onset of the metabolic process of diabetes mellitus. As a result of these structural changes, lower scotopic and photopic amplitudes, decreased OP amplitudes, and prolonged implicit times in flash ERG were obtained.


Asunto(s)
Electrorretinografía , Tomografía de Coherencia Óptica , Humanos , Electrorretinografía/métodos , Masculino , Tomografía de Coherencia Óptica/métodos , Femenino , Persona de Mediana Edad , Anciano , Adulto , Angiografía con Fluoresceína/métodos , Retinopatía Diabética/fisiopatología , Retinopatía Diabética/diagnóstico por imagen , Vasos Retinianos/diagnóstico por imagen , Vasos Retinianos/fisiopatología , Estudios de Casos y Controles , Fóvea Central/diagnóstico por imagen , Fóvea Central/irrigación sanguínea , Fóvea Central/fisiopatología , Diabetes Mellitus/fisiopatología , Diabetes Mellitus/diagnóstico por imagen , Retina/diagnóstico por imagen , Retina/fisiopatología
2.
Am J Ophthalmol Case Rep ; 36: 102094, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39100576

RESUMEN

Purpose: Cone-rod dystrophies (CORD) are inherited retinal dystrophies characterized by primary cone degeneration with secondary rod involvement. We report two patients from the same family with a dominant variant in the guanylate cyclase 2D (GUCY2D) gene with different phenotypes in the electroretinogram (ERG). Observations: A 21-year-old lady (Patient 1) was referred due to experiencing blurry vision and color vision impairment. Visual field testing revealed a central scotoma. Spectral-domain optical coherence tomography (SD-OCT) and fundus autofluorescence (FAF) documented macula dysfunction. Reduced amplitude was observed in the photopic responses of ERG. Her 54-year-old father (Patient 2) had similar issues with blurry vision. A dilated fundus examination displayed bilateral macular atrophy. Loss of the ellipsoid zone line and collapse of the outer nuclear segment were noted on the SD-OCT. Photopic ERG responses were extinguished, and an electronegative ERG was observed in the dark-adapted 3.0 ERG. The gene report revealed a c.2512C > T (p.Arg838Cys) variant in GUCY2D for both patients. They were respectively diagnosed as cone dystrophy (COD) and cone-rod dystrophy (CORD). Conclusions: We report two different clinical phenotypes in GUCY2D-associated COD despite sharing the same variant. A dysfunction in the synaptic junction between the photoreceptor and the secondary neuron was proposed to explain the electronegative ERG. This explanation might extend to other gene-related cases of CORD with electronegative ERG.

3.
Yonago Acta Med ; 67(3): 280-283, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39193137

RESUMEN

This study aimed to determine whether more stable electroretinography parameters could be obtained in younger children using skin electrodes placed at the inner canthus and ears compared to using contact lens electrodes. The study included three Japanese patients (two girls and one boy) who presented with epileptic spasms before the age of 3 years. We compared the electroretinography parameters obtained with skin electrodes and contact lens electrodes. We could record reproducible results using skin ERG with a montage of electrodes placed at the inner canthus and the ear in children. Moreover, standard data for younger children were created, enabling the evaluation of electroretinography parameters recorded with skin electrodes in individual pediatric patients. The skin electroretinography using the new montage may be stable parameters for evaluating retinal function in younger children.

4.
Neurosci Biobehav Rev ; 164: 105833, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39089420

RESUMEN

Major Depressive Disorder (MDD) is characterized by at least one major depressive episode. It requires medical attention typically involving the prescription of antidepressants. Remission in MDD patients is often difficult to achieve because of the limited effectiveness of these drugs. Nowadays, numerous patients undergo various antidepressant treatments, with subjective changes in their personal experiences being regularly monitored. Therefore, it is essential to find clinical and objective tools that offer a more tailored approach to antidepressant selection. The neurochemistry of the retina being similar to the brain, one promising approach would be to use ElectroRetinoGraphy (ERG) measurements on MDD patients requiring antidepressant treatment. Thus, the aim of this scoping review is to highlight effects of different classes of antidepressants on retinal function evaluated by full-field ERG (ffERG), Pattern ERG (PERG) and multifocal ERG (mfERG) waveforms in MDD patients. These ERG measurements could serve as pivotal indicators in defining patient profiles, facilitating a more objective and personalized approach to therapeutic interventions, thereby advancing precision psychiatry.


Asunto(s)
Antidepresivos , Trastorno Depresivo Mayor , Electrorretinografía , Humanos , Trastorno Depresivo Mayor/tratamiento farmacológico , Trastorno Depresivo Mayor/fisiopatología , Antidepresivos/farmacología , Antidepresivos/uso terapéutico , Retina/efectos de los fármacos , Retina/fisiopatología
5.
Curr Eye Res ; : 1-6, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39212476

RESUMEN

PURPOSE: This study aimed to assess and compare the retinal toxicity associated with silicone oil (SO) and perfluoropropane (C3F8) tamponade following vitreoretinal surgery for fresh rhegmatogenous retinal detachment (RRD), utilizing the office-based Diopsys® NOVA™ system for evaluation. METHODS: Patients who underwent vitreoretinal surgery for fresh RRD and had SO (group 1) or C3F8 (group 2) tamponade were included in a prospective analysis. Flicker full field electroretinography (ffERG) and pattern electroretinography (PERG) tests were performed at 6 months postoperatively. RESULTS: Postoperative best corrected visual acuity (logMAR) was significantly different in group 1 and group 2 patients, 0.48 ± 0.3 and 0.30 ± 0.2, respectively. No significant disparities were found in demographic variables. Flicker ffERG and PERG recordings revealed notable alterations in retinal function parameters in the group 1 compared to the group 2. CONCLUSION: Our findings suggest a correlation between SO tamponade and retinal dysfunction, evidenced by office-based ERG measurements. The Diopsys® NOVA™ protocol offers clinical ease in assessing retinal function. Further controlled studies are essential to validate these findings and guide clinical practice effectively.

6.
Front Cell Dev Biol ; 12: 1422764, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38966426

RESUMEN

Purpose: Extraocular electrical stimulation is known to provide neuroprotection for retinal cells in retinal and optic nerve diseases. Currently, the treatment approach requires patients to set up extraocular electrodes and stimulate potentially weekly due to the lack of an implantable stimulation device. Hence, a minimally-invasive implant was developed to provide chronic electrical stimulation to the retina, potentially improving patient compliance for long-term use. The aim of the present study was to determine the surgical and stimulation safety of this novel device designed for neuroprotective stimulation. Methods: Eight normally sighted adult feline subjects were monocularly implanted in the suprachoroidal space in the peripheral retina for 9-39 weeks. Charge balanced, biphasic, current pulses (100 µA, 500 µs pulse width and 50 pulses/s) were delivered continuously to platinum electrodes for 3-34 weeks. Electrode impedances were measured hourly. Retinal structure and function were assessed at 1-, 2-, 4-, 6- and 8-month using electroretinography, optical coherence tomography and fundus photography. Retina and fibrotic thickness were measured from histological sections. Randomized, blinded histopathological assessments of stimulated and non-stimulated retina were performed. Results: All subjects tolerated the surgical and stimulation procedure with no evidence of discomfort or unexpected adverse outcomes. The device position was stable after a post-surgery settling period. Median electrode impedance remained within a consistent range (5-10 kΩ) over time. There was no change in retinal thickness or function relative to baseline and fellow eyes. Fibrotic capsule thickness was equivalent between stimulated and non-stimulated tissue and helps to hold the device in place. There was no scarring, insertion trauma, necrosis, retinal damage or fibroblastic response in any retinal samples from implanted eyes, whilst 19% had a minimal histiocytic response, 19% had minimal to mild acute inflammation and 28% had minimal to mild chronic inflammation. Conclusion: Chronic suprathreshold electrical stimulation of the retina using a minimally invasive device evoked a mild tissue response and no adverse clinical findings. Peripheral suprachoroidal electrical stimulation with an implanted device could potentially be an alternative approach to transcorneal electrical stimulation for delivering neuroprotective stimulation.

7.
Neurobiol Aging ; 141: 171-181, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38964014

RESUMEN

Age-related neuronal adaptations are known to help maintain function. This study aims to examine gross age-related in vivo retinal functional adaptations (using electroretinography) in young and middle aged C57BL/6J and Thy1-YFPh mice and to relate this to in vivo retinal structure (using optical coherence tomography). Electroretinography responses were generally larger in Thy1-YFPh mice than in C57BL/6J mice, with similar in vivo retinal layer thicknesses except for longer inner/outer photoreceptor segment in Thy1-YFPh mice. Relative to 3-month-old mice, 12-month-old mice showed reduced photoreceptor (C57BL/6J 84.0±2.5 %; Thy1-YFPh 80.2±5.2 %) and bipolar cell (C57BL/6J 75.6±2.3 %; Thy1-YFPh 68.1±5.5 %) function. There was relative preservation of ganglion cell function (C57BL/6J 79.7±3.7 %; Thy1-YFPh 91.7±5.0 %) with age, which was associated with increased b-wave (bipolar cell) sensitivities to light. Ganglion cell function was correlated with both b-wave amplitude and sensitivity. This study shows that there are normal age-related adaptations to preserve functional output. Different mouse strains may have varied age-related adaptation capacity and should be taken into consideration when examining age-related susceptibility to injury.


Asunto(s)
Envejecimiento , Electrorretinografía , Retina , Animales , Masculino , Ratones , Envejecimiento/fisiología , Envejecimiento/patología , Ratones Endogámicos C57BL , Ratones Transgénicos , Retina/fisiología , Células Bipolares de la Retina/fisiología , Células Ganglionares de la Retina/fisiología , Antígenos Thy-1/genética , Tomografía de Coherencia Óptica/métodos
8.
Dis Model Mech ; 17(8)2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39056117

RESUMEN

N-methyl-D-aspartate (NMDA)-induced retinal damage has been well studied in rodents, but the detailed mechanisms have not yet been characterized in nonhuman primates. Here, we characterized the retinal degenerative effects of NMDA on rhesus monkeys in vivo. NMDA saline or saline-only control was injected intravitreally to the randomly assigned eyes and contralateral eyes of four rhesus monkeys, respectively. The structural and functional changes of retina were characterized by optical coherence tomography and electroretinography on days 0, 4, 30 and 60 post injection. Both optic discs and macular areas of the NMDA-injected eyes initially presented with a transient retinal thickening, followed by continued retinal thinning. The initial, transient retinal thickening has also been observed in glaucoma patients, but this has not been reported in rodent NMDA models. This initial response was followed by loss of retina ganglion cells (RGCs), which is similar to glaucomatous optic neuropathy and other RGC-related retinal degenerations. The amplitudes of both the photopic negative response and pattern electroretinogram decreased significantly and remained low until the end of the study. Thus, the NMDA monkey model may serve as a more clinically relevant animal model of retinal damage.


Asunto(s)
Modelos Animales de Enfermedad , Electrorretinografía , Macaca mulatta , N-Metilaspartato , Retina , Tomografía de Coherencia Óptica , Animales , Retina/patología , Retina/efectos de los fármacos , Células Ganglionares de la Retina/patología , Células Ganglionares de la Retina/efectos de los fármacos , Masculino
9.
J Sleep Res ; : e14278, 2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-38993053

RESUMEN

Hypersomnia spectrum disorders are underdiagnosed and poorly treated due to their heterogeneity and absence of biomarkers. The electroretinography has been proposed as a proxy of central dysfunction and has proved to be valuable to differentiate certain psychiatric disorders. Hypersomnolence is a shared core feature in central hypersomnia and psychiatric disorders. We therefore aimed to identify biomarkers by studying the electroretinography profile in patients with narcolepsy type 1, idiopathic hypersomnia and in controls. Cone, rod and retinal ganglion cells electrical activity were recorded with flash-electroretinography in non-dilated eye of 31 patients with idiopathic hypersomnia (women 84%, 26.6 ± 5.9 years), 19 patients with narcolepsy type 1 (women 63%, 36.6 ± 12.7 years) and 43 controls (women 58%, 30.6 ± 9.3 years). Reduced cone a-wave amplitude (p = 0.039) and prolonged cone (p = 0.022) and rod b-wave (p = 0.009) latencies were observed in patients with narcolepsy type 1 as compared with controls, while prolonged photopic negative response-wave latency (retinal ganglion cells activity) was observed in patients with idiopathic hypersomnia as compared with controls (p = 0.033). The rod and cone b-wave latency clearly distinguished narcolepsy type 1 from idiopathic hypersomnia and controls (area under the curve > 0.70), and the photopic negative response-wave latency distinguished idiopathic hypersomnia and narcolepsy type 1 from controls with an area under the curve > 0.68. This first original study shows electroretinography anomalies observed in patients with hypersomnia. Narcolepsy type 1 is associated with impaired cone and rod responses, whereas idiopathic hypersomnia is associated with impaired retinal ganglion cells response, suggesting different phototransduction alterations in both hypersomnias. Although these results need to be confirmed with a larger sample size, the electroretinography may be a promising tool for clinicians to differentiate hypersomnia subtypes.

10.
Exp Neurobiol ; 33(3): 152-164, 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-38993082

RESUMEN

The harmful effects of blue light on the retina and health issues attributed to flickering light have been researched extensively. However, reports on the effects of flickering blue light at a frequency in the visible range on the retina are limited. This study aimed to non-invasively investigate the structural and functional changes in mice retinas following exposure to flickering blue light. BALB/c mice were subjected to non-flickering and flickering blue light, and changes in the retinal function and structure were assessed using electroretinography (ERG) and spectral-domain optical coherence tomography (SD-OCT), respectively. Retinal damage progression was monitored on days 3, 7, 14, and 42 following light exposure. Significant reductions in scotopic and photopic ERG responses were observed on day 3 (p<0.05). On day 7, the non-flickering and flickering groups demonstrated different functional changes: the flickering group showed further ERG response reduction, while the non-flickering group showed no reduction or slight improvement that was statistically insignificant (p>0.05). A similar trend lasted by day 14. On day 42, however, the difference between the non-flickering and flickering groups was significant, which was corroborated by the normalized amplitudes at 0, 0.5, and 1 log cd s/m2 (p<0.05). Quantitative and qualitative SD-OCT assays revealed more severe and progressive retinal damage in the flickering group throughout the study. Flickering blue light causes more persistent and severe retinal damage than non-flickering blue light and may be a risk factor for retinal degeneration even at frequencies as low as 20 Hz.

11.
Diagnostics (Basel) ; 14(14)2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-39061613

RESUMEN

Purtscher retinopathy is a rare but severe sight-threatening eye condition that mostly occurs in middle-aged men after chest compression or head injury. In cases such as acute pancreatitis, connective tissue disorders, kidney failure or COVID-19 infection with similar ocular findings but no history of trauma, a diagnosis of Purtscher-like retinopathy is made. We present a case of a 72-year-old female with typical symptoms of Purtscher retinopathy in both eyes after a car crash accident. Although the pathophysiology of the disease is not fully understood, the main cause of Purtscher retinopathy seems to be an embolic occlusion of the precapillary arterioles which supply the superficial peripapillary capillaries. Activation of the C5a component of the complement predisposes the leukocytes to aggregation, which obstructs blood flow. The main symptom of Purtscher retinopathy is sudden, painless deterioration of vision which occurs up to 48 h after the injury. In most patients, the changes observed in the fundus of the eye resolve within several months, and visual acuity slowly improves, sometimes even returning to the state from before the injury. However, risk factors such as older age, high hyperopia, and late treatment implementation can make the prognosis less favorable.

12.
Front Vet Sci ; 11: 1407928, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39021405

RESUMEN

Background: This study aimed to determine the effects of intramuscular (IM) administration of alfaxalone with or without dexmedetomidine on short electroretinography (ERG), ocular parameters and cardiorespiratory in healthy cats. Methods: Eight healthy female spayed cats were treated with three sedation protocols: IM administration of 5 µg/kg dexmedetomidine (DEX), 5 mg/kg alfaxalone (ALF), and 5 µg/kg dexmedetomidine plus 5 mg/kg alfaxalone (DEX + ALF). The washout period after each treatment was 2 weeks. Physiological parameters, time metrics, intraocular pressure (IOP), Schirmer tear test 1 (STT-1) and a short ERG protocol were recorded. For age data, weight data, time metrics and ERG data, one-way ANOVA with Bonferroni posterior comparisons were performed. For physiological parameters, IOP and STT-1 data, two-way repeated measures ANOVA with Bonferroni posterior comparisons were performed. Statistical significance was set at a p-value <0.05. Results: IOPs were increased in all three groups compared to baseline and showed no significant differences among three groups at any time point. STT-1 values were decreased significantly during the process. Significant differences were noticed between a-wave amplitude in the dark-adapted response between DEX and ALF, and a-wave amplitude in light-adapted response between ALF and DEX + ALF. Conclusion: This study demonstrates the feasibility of three sedation protocols for short ERG recording in cats. All these treatments resulted in increased IOP values and reduced STT-1 values. But baseline data of ERG was not obtained as a blank control in cats.

13.
Sci Rep ; 14(1): 16490, 2024 07 17.
Artículo en Inglés | MEDLINE | ID: mdl-39019967

RESUMEN

Retinitis Pigmentosa is a leading cause of severe vision loss. Retinitis Pigmentosa can present with a broad range of phenotypes impacted by disease age of onset, severity, and progression. This variation is influenced both by different gene mutations as well as unique variants within the same gene. Mutations in the nuclear hormone receptor 2 family e, member 3 are associated with several forms of retinal degeneration, including Retinitis Pigmentosa. In our previous studies we demonstrated that subretinal administration of one Nr2e3 dose attenuated retinal degeneration in rd7 mice for at least 3 months. Here we expand the studies to evaluate the efficacy and longitudinal impact of the NR2E3 therapeutic by examining three different doses administered at early or intermediate stages of retinal degeneration in the rd7 mice. Our study revealed retinal morphology was significantly improved 6 months post for all doses in the early-stage treatment groups and for the low and mid doses in the intermediate stage treatment groups. Similarly, photoreceptor function was significantly improved in the early stage for all doses and intermediate stage low and mid dose groups 6 months post treatment. This study demonstrated efficacy in multiple doses of NR2E3 therapy.


Asunto(s)
Modelos Animales de Enfermedad , Receptores Nucleares Huérfanos , Degeneración Retiniana , Animales , Ratones , Degeneración Retiniana/genética , Degeneración Retiniana/patología , Degeneración Retiniana/tratamiento farmacológico , Receptores Nucleares Huérfanos/genética , Receptores Nucleares Huérfanos/metabolismo , Retinitis Pigmentosa/genética , Retinitis Pigmentosa/patología , Retinitis Pigmentosa/tratamiento farmacológico , Retina/patología , Retina/metabolismo , Retina/efectos de los fármacos
14.
Doc Ophthalmol ; 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38825634

RESUMEN

PURPOSE: Vitamin A is a lipid-soluble compound that is critical in maintaining phototransduction. Ocular manifestations of hypovitaminosis A may present with anterior segment signs of xeropthalmia, with advanced cases also causing classic retinal and electrophysiologic changes of vitamin A deficiency retinopathy. We present a case of vitamin A deficiency retinopathy, with corresponding retinal imaging and electrophysiology, in an adult patient with celiac disease and liver fibrosis. METHODS: A single case report was conducted in Toronto, Canada. RESULTS: A 77-year-old male with known celiac disease and liver fibrosis presented progressively worsening vision noticed primarily when driving. Vision was 20/50 OD and 20/200 OS. Bitot spots were noted on anterior segment examination. Fundus photography demonstrated bilateral peripheral macular hypopigmentation and far-peripheral granular retinal hypopigmentation with focal yellow dots and hyper-pigmented deposits. Optical coherence tomography (OCT) imaging demonstrated indistinct outer retinal banding with mild outer nuclear layer thinning, focal hyper-reflective deposits, and a thin choroid bilaterally. Full-field electroretinography (ERG) testing demonstrated reduced rod-isolated and combined rod-cone response amplitudes, and multifocal ERG testing demonstrated blunted individual responses throughout the field. The patient was treated with pulse vitamin A therapy. After 6 months of therapy, ERG responses were back within reference range, and the outer retinal changes reversed; visual acuity improved to 20/30 OD and 20/40 OS. CONCLUSION: This case represents the classic findings of vitamin A deficiency retinopathy on fundus examination and electrophysiologic testing secondary to gastrointestinal pathology. Prompt treatment of high dose vitamin A supplementation led to improvement of full-field and multifocal ERG results, as well as reconstitution of outer retinal architecture.

15.
Sci Rep ; 14(1): 14733, 2024 06 26.
Artículo en Inglés | MEDLINE | ID: mdl-38926421

RESUMEN

In electroretinographic (ERG) recordings of zebrafish, the light stimulus is usually delivered by a fiber optic cable. The purpose of this study was to determine whether the angle of incidence of the stimulus light from the fiber optic cable will affect the amplitudes and implicit times of the ERGs of zebrafish larvae. The larvae were positioned on their side with the right eye pointed upward. The light stimuli were delivered by a fiber optic cable from three directions of the larvae: frontal 0° (F0°), dorsal 30°(D30°), and ventral 30°(V30°). Photopic ERGs were recorded from 16 larvae at age 5-6 days post-fertilization. Our results showed that the mean amplitude of the b-wave elicited at D30° and V30° stimulation was significantly smaller than that elicited at F0° stimulation (P = 0.014 and P = 0.019, respectively). In addition, the mean amplitude of the d-wave elicited at D30° and V30° stimulation was significantly smaller than that elicited at F0° stimulation (P < 0.0001 and P = 0.015, respectively). However, the difference between the b-wave amplitudes elicited at D30° and V30° stimuli were not significant (P = 0.98), and the d-wave amplitudes were also not significantly different (P = 0.20). The average b-wave amplitudes elicited at D30° stimulation was 84.6 ± 15.7% and V30° stimulation was 84.8 ± 17.4% relative to that of F0° stimulation. The average d-wave amplitudes elicited by D30° stimulation was 85.5 ± 15.2% and by V30° stimulation was 79.0 ± 11.0% relative to that of F0° stimulation. The differences in the implicit times of the b- and d-wave elicited by the different directions of stimulation were not significant (P = 0.52 and P = 0.14, respectively). We conclude that the amplitude of the photopic ERGs is affected by the angle of the incident light. Thus, it would be better to use ganzfeld stimuli to elicit maximum b- and d-wave amplitudes of the photopic ERGs of zebrafish larvae.


Asunto(s)
Electrorretinografía , Larva , Luz , Estimulación Luminosa , Pez Cebra , Animales , Pez Cebra/fisiología , Larva/fisiología , Retina/fisiología
16.
Front Cell Neurosci ; 18: 1404987, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38863499

RESUMEN

Diabetic retinopathy (DR) is a leading cause of blindness and vision impairment worldwide and represents one of the most common complications among diabetic patients. Current treatment modalities for DR, including laser photocoagulation, intravitreal injection of corticosteroid, and anti-vascular endothelial growth factor (VEGF) agents, target primarily vascular lesions. However, these approaches are invasive and have several limitations, such as potential loss of visual function, retinal scars and cataract formation, and increased risk of ocular hypertension, vitreous hemorrhage, retinal detachment, and intraocular inflammation. Recent studies have suggested mitochondrial dysfunction as a pivotal factor leading to both the vascular and neural damage in DR. Given that Coenzyme Q10 (CoQ10) is a proven mitochondrial stabilizer with antioxidative properties, this study investigated the effect of CoQ10 eyedrops [in conjunction with vitamin E d-α-tocopheryl poly(ethylene glycol) 1000 succinate (TPGS)] on DR-induced neurodegeneration using a type 2 diabetes mouse model (C57BLKsJ-db/db mice). Utilizing a comprehensive electroretinography protocol, supported by immunohistochemistry, our results revealed that topical application of CoQ10 eyedrops conjugated with vitamin E TPGS produced a neuroprotective effect against diabetic-induced neurodegeneration by preserving the function and histology of various retinal neural cell types. Compared to the control group, mice treated with CoQ10 exhibited thicker outer and inner nuclear layers, higher densities of photoreceptor, cone cell, and rod-bipolar cell dendritic boutons, and reduced glial reactivity and microglial cell density. Additionally, the CoQ10 treatment significantly alleviated retinal levels of MMP-9 and enhanced mitochondrial function. These findings provide further insight into the role of mitochondrial dysfunction in the development of DR and suggest CoQ10 eyedrops, conjugated with vitamin E TPGS, as a potential complementary therapy for DR-related neuropathy.

17.
Acta Vet Hung ; 72(2): 80-98, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38916958

RESUMEN

The aim of the study was to characterize retinal atrophy (RA) with progressive retinal atrophy symptoms in mixed breed dogs using ophthalmoscopy, spectral domain optical coherence tomography (SD-OCT) and electroretinography (ERG).The study was performed on 13 mixed breed dogs affected by retinal atrophy (11 males and 2 females that were 1.5-14 years old). Depending on the advancement of RA, SD-OCT examinations identified retinal abnormalities ranging from layer disorganisation to advanced atrophy. The most advanced RA occurred ventral to the optic disc. Total retinal thickness in both eyes (mean ± SD) was lower in dogs with RA compared to controls dorsally (77.7 ± 39.5 µm vs 173.5 ± 13.3 µm), ventrally (33.4 ± 29.9 µm vs 139.5 ± 10.8 µm), nasally (65.0 ± 34.5 µm vs 163.9 ± 11.0 µm) and temporally (61.8 ± 41.7 µm vs 171.9 ± 11.1 µm) to the optic disc. In dogs with locally normal architecture of inner retina, loss of definition of outer retinal layers occurred in many regions. Dark and light-adapted ERGs were reduced in 2 dogs with RA and were unrecordable in 11 dogs. Lesions evident in SD-OCT scans of mixed breed dogs affected with retinal atrophy initially appear ventrally to the optic disc and ventro-dorsally in advanced RA. In all mixed breed dogs with retinal atrophy, clinical signs and SD-OCT results correlate with ERG findings.


Asunto(s)
Enfermedades de los Perros , Electrorretinografía , Tomografía de Coherencia Óptica , Animales , Perros , Tomografía de Coherencia Óptica/veterinaria , Enfermedades de los Perros/diagnóstico por imagen , Enfermedades de los Perros/patología , Femenino , Electrorretinografía/veterinaria , Masculino , Retina/diagnóstico por imagen , Retina/patología , Enfermedades de la Retina/veterinaria , Enfermedades de la Retina/diagnóstico por imagen , Enfermedades de la Retina/patología , Atrofia/veterinaria
18.
Ophthalmol Retina ; 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38782117

RESUMEN

PURPOSE: Autosomal dominant neovascular inflammatory vitreoretinopathy (ADNIV) is a rare genetic (CAPN5) autoimmune condition typically diagnosed in adulthood and characterized by a triad of inflammation, retinal degeneration, and neovascularization. We report novel multimodal imaging findings in children and young adults with ADNIV, and early treatment response to short-duration local and systemic corticosteroids. DESIGN: Retrospective consecutive case series. PARTICIPANTS: Ten patients aged <25 years with ADNIV and available multimodal imaging. METHODS: The medical records of patients aged <25 years with a diagnosis of ADNIV with ultrawidefield fluorescein angiography (UWFFA) and OCT data were reviewed. MAIN OUTCOME MEASURES: Ultrawidefield fluorescein angiography and OCT findings at baseline and after local corticosteroids. RESULTS: Median age at presentation was 14 years (range, 9-24 years). OCT on presentation demonstrated cystoid macular edema in 8 of 20 eyes and symptomatic vitreoretinal interface disease in 2 of 20 eyes. Initial UWFFA demonstrated retinal vascular leakage (20/20 eyes, 100%), peripheral nonperfusion (13/20 eyes, 65%), and retinal neovascularization (6/20 eyes, 30%). Retinal vascular leakage improved with local corticosteroids, and neovascularization regressed with anti-VEGF therapy. CONCLUSIONS: Ultrawidefield fluorescein angiography findings of prefibrotic ADNIV reported in adults were also present in children and young adults. Early testing for a pathogenic CAPN5 variant in at-risk children and regularly scheduled screening for uveitis and retinal vasculitis with UWFFA and OCT may prompt earlier intervention. Short-duration local steroids are effective at treating retinal vascular leakage and macular edema but are not durable, suggesting a potential role for steroid-sparing immunosuppressive therapy. Early treatment may alter the natural history of disease. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

19.
Geroscience ; 46(5): 4707-4728, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38795184

RESUMEN

Aging is accompanied by an increased prevalence of degenerative conditions, including those affecting ocular health, which significantly impact quality of life and increase the burden on healthcare systems. Among these, retinal aging is of particular concern due to its direct link to vision impairment, a leading cause of disability in the elderly. Vision loss in the aging population is associated with heightened risks of cognitive decline, social isolation, and morbidity. This study addresses the critical gap in our understanding of modifiable lifestyle factors, such as physical exercise, that may mitigate retinal aging and its related pathologies. We investigated the effects of different exercise regimens-voluntary (recreational-type) and forced (high-intensity)-on the retinal health of aging Wistar rats (18-month-old), serving as a model for studying the translational potential of exercise interventions in humans. Male Wistar rats were divided into four groups: a young control (3-month-old) for baseline comparison, an aged sedentary control, an aged group engaging in voluntary exercise via a running wheel in their cage, and an aged group subjected to forced exercise on a treadmill for six sessions of 20 min each per week. After a 6-month experimental period, we assessed retinal function via electroretinography (ERG), measured retinal thickness histologically, and analyzed protein expression changes relevant to oxidative stress, inflammation, and anti-aging mechanisms. Our findings reveal that voluntary exercise positively impacts retinal function and morphology, reducing oxidative stress and inflammation markers while enhancing anti-aging protein expression. In contrast, forced exercise showed diminished benefits. These insights underscore the importance of exercise intensity and preference in preserving retinal health during aging. The study highlights the potential of recreational physical activity as a non-invasive strategy to counteract retinal aging, advocating for further research into exercise regimens as preventative therapies for age-related ocular degenerations.


Asunto(s)
Envejecimiento , Electrorretinografía , Condicionamiento Físico Animal , Ratas Wistar , Retina , Animales , Condicionamiento Físico Animal/fisiología , Condicionamiento Físico Animal/métodos , Masculino , Envejecimiento/fisiología , Ratas , Estrés Oxidativo/fisiología
20.
Int Med Case Rep J ; 17: 447-454, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38765868

RESUMEN

Purpose: To determine whether 0.025% povidone-iodine (0.025% PI) in the irrigation solution during vitrectomy for endophthalmitis is safe. Methods: Two cases of bleb-associated endophthalmitis were treated with vitrectomy using 0.025% PI in the irrigation solution. The RETevel electroretinographic (ERG) system with skin electrodes was used to assess the physiology of the retina pre- and postoperatively. Case: Case 1 was a 46-year-old man who had atopic keratoconjunctivitis and underwent trabeculectomy with the creation of a bleb after there was a rise in the intraocular pressure. One month postoperatively, a mild filtering bleb-associated endophthalmitis developed, and the eye was treated with intravitreal and subconjunctival injections of vancomycin (VCM) and ceftazidime (CAZ). After three days, the fundus was not visible and B-mode echography showed an area of high brightness in the retina. Vitrectomy with irrigation with VCM and CAZ, and 0.025% PI was performed successfully. Pre- and postoperative ERGs showed an improvement in both the a- and b-wave amplitudes and the b/a ratio was stable at 2.0. Case 2 was a 63-year-old man who had undergone trabeculectomy for glaucoma. Five years later, the eye developed blebitis which was treated with topical and subconjunctival injections of VCM and CAZ. Three days later, vitreous opacities appeared and a high brightness area was seen in the B-mode echographic images. Vitrectomy with VCM and CAZ, and 0.025% PI irrigation was successfully performed. Comparisons of the pre- and postoperative ERGs found that the a- and b- wave amplitudes of the ERGs increased and the b/a ratio was stable at approximately 1.5. Conclusion: Vitrectomy with 0.025% PI irrigation is safe and ERG recordings with skin electrodes can be used to evaluate the pre- and postoperative retinal physiology safely.


We report our findings in two cases of bleb-related endophthalmitis that underwent pars plana vitrectomy (PPV) with irrigation with 0.025% povidone-iodine (PI)-Balanced Salt Solution (BSS) PLUS (Alcon Laboratories, Fort Worth, TX). The retinal function was evaluated by full-field electroretinograms (ERGs) recorded with skin electrodes before and after the vitrectomy. At present, there is no consensus on whether patients with bleb-related endophthalmitis should be treated with PPV or treated solely by intravitreal antibiotics. It was recently reported that vitrectomy using an irrigation solution containing 0.025% PI followed by postoperative antibiotics was effective and safe for the treatment of endogenous endophthalmitis and postoperative endophthalmitis. However, iodine is known to be retinotoxic depending on its concentration. Electroretinography is a useful method to evaluate the safety of medications because it represents the physiology of the entire retina. However, conventional recording procedures with contact lens electrodes cannot be used in eyes with bleb associated endophthalmitis. Therefore, we performed ERG using skin electrodes which were introduced relatively recently. As a result, electroretinographic response showed that retinal function was not altered after surgery in these two cases.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA