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1.
Neural Plast ; 2019: 6208414, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31558900

RESUMEN

Dichoptic movie viewing has been shown to significantly improve visual acuity in amblyopia in children. Moreover, short-term occlusion of the amblyopic eye can transiently increase its contribution to binocular fusion in adults. In this study, we first asked whether dichoptic movie viewing could improve the visual function of amblyopic subjects beyond the critical period. Secondly, we tested if this effect could be enhanced by short-term monocular occlusion of the amblyopic eye. 17 subjects presenting stable functional amblyopia participated in this study. 10 subjects followed 6 sessions of 1.5 hour of dichoptic movie viewing (nonpatched group), and 7 subjects, prior to each of these sessions, had to wear an occluding patch over the amblyopic eye for two hours (patched group). Best-corrected visual acuity, monocular contrast sensitivity, interocular balance, and stereoacuity were measured before and after the training. For the nonpatched group, mean amblyopic eye visual acuity significantly improved from 0.54 to 0.46 logMAR (p < 0.05). For the patched group, mean amblyopic eye visual acuity significantly improved from 0.62 to 0.43 logMAR (p < 0.05). Stereoacuity improved significantly when the data of both groups were combined. No significant improvement was observed for the other visual functions tested. Our training procedure combines modern video technologies and recent fundamental findings in human plasticity: (i) long-term plasticity induced by dichoptic movie viewing and (ii) short-term adaptation induced by temporary monocular occlusion. This passive dichoptic movie training approach is shown to significantly improve visual acuity of subjects beyond the critical period. The addition of a short-term monocular occlusion to the dichoptic training shows promising trends but was not significant for the sample size used here. The passive movie approach combined with interocular contrast balancing even over such a short period as 2 weeks has potential as a clinical therapy to treat amblyopia in older children and adults.


Asunto(s)
Ambliopía/fisiopatología , Ojo/fisiopatología , Visión Binocular/fisiología , Agudeza Visual/fisiología , Adolescente , Adulto , Anciano , Niño , Período Crítico Psicológico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Tiempo , Adulto Joven
2.
Ocul Immunol Inflamm ; 28(8): 1293-1297, 2020 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-33021856

RESUMEN

A 53-year-old man presented with acute loss of vision, negative scotoma and dyschromatopsia in his left eye. He reported contact with people with severe respiratory syndrome - coronavirus-2 (SARS-CoV-2) 8 days prior symptoms. Funduscopic examination revealed several retinal hemorrhages. Spectral-domain optical coherence tomography showed lesions consistent with acute macular neuroretinopathy and paracentral acute middle maculopathy. Quickly after his presentation, SARSCov-2 was confirmed by chest computed tomography-scan and RT-PCR in this patient. Thrombotic complications associated with Covid-19 infection have high incidence and may involve the retina. We described a case of retinal involvement associated with Covid-19 infection. PRÉCIS: Funduscopic examination revealed retinal hemorrhages in a man with loss of vision. Optical coherence tomography showed an acute macular neuroretinopathy and paracentral acute middle maculopathy. Coronavirus disease was confirmed by chest computed tomography-scan and RT-PCR.


Asunto(s)
Betacoronavirus , Infecciones por Coronavirus/complicaciones , Angiografía con Fluoresceína/métodos , Mácula Lútea/patología , Neumonía Viral/complicaciones , Enfermedades de la Retina/etiología , Tomografía de Coherencia Óptica/métodos , Agudeza Visual , Enfermedad Aguda , COVID-19 , Infecciones por Coronavirus/epidemiología , Fondo de Ojo , Humanos , Masculino , Persona de Mediana Edad , Oftalmoscopía , Pandemias , Neumonía Viral/epidemiología , Enfermedades de la Retina/diagnóstico , SARS-CoV-2
3.
Sci Rep ; 10(1): 21792, 2020 12 11.
Artículo en Inglés | MEDLINE | ID: mdl-33311546

RESUMEN

For normally sighted readers, word neighborhood size (i.e., the total number of words that can be formed from a single word by changing only one letter) has a facilitator effect on word recognition. When reading with central field loss (CFL) however, individual letters may not be correctly identified, leading to possible misidentifications and a reverse neighborhood size effect. Here we investigate this inhibitory effect of word neighborhood size on reading performance and whether it is modulated by word predictability and reading proficiency. Nineteen patients with binocular CFL from 32 to 89 years old (mean ± SD = 75 ± 15) read short sentences presented with the self-paced reading paradigm. Accuracy and reading time were measured for each target word read, along with its predictability, i.e., its probability of occurrence following the two preceding words in the sentence using a trigram analysis. Linear mixed effects models were then fit to estimate the individual contributions of word neighborhood size, predictability, frequency and length on accuracy and reading time, while taking patients' reading proficiency into account. For the less proficient readers, who have given up daily reading as a consequence of their visual impairment, we found that the effect of neighborhood size was reversed compared to normally sighted readers and of higher amplitude than the effect of frequency. Furthermore, this inhibitory effect is of greater amplitude (up to 50% decrease in reading speed) when a word is not easily predictable because its chances to occur after the two preceding words in a specific sentence are rather low. Severely impaired patients with CFL often quit reading on a daily basis because this task becomes simply too exhausting. Based on our results, we envision lexical text simplification as a new alternative to promote effective rehabilitation in these patients. By increasing reading accessibility for those who struggle the most, text simplification might be used as an efficient rehabilitation tool and daily reading assistive technology, fostering overall reading ability and fluency through increased practice.


Asunto(s)
Atención , Lectura , Baja Visión/fisiopatología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad
4.
Sci Rep ; 10(1): 4527, 2020 03 11.
Artículo en Inglés | MEDLINE | ID: mdl-32161332

RESUMEN

The purpose of this study is to evaluate the efficacy and complications of the XEN implant as a solo procedure or in association with cataract surgery in patients with open angle glaucoma (OAG). All patients who received a XEN implant between June 2017 and June 2018 were included in the study. The primary and secondary outcomes were: the reduction of the intraocular pressure (IOP) at 6 months postoperatively, the decrease of the glaucoma medications 6 months after surgery, the clinical success rate (eyes (%) achieving ≥20% IOP reduction on the same or fewer medications without secondary surgical intervention), the frequency and type of postoperative interventions as well as the complication rate. We included one hundred and seven eyes from 97 patients with primary OAG (79%), or secondary OAG (21%). Seventy-seven patients (72%) received a standalone XEN implantation and 30 (28%) underwent XEN implantation combined with phacoemusification. The IOP decreased from 20.4 mm Hg ± 6.4 preoperatively to 15.4 mm Hg ± 5.3 six months after the surgery, which represented a reduction of 24.5% (P = 1.4.10-7). It was associated with a lowering of glaucoma medications from 2.8 ± 1.0 preoperatively to 0.6 ± 1.0 six months postoperatively (P = 3.6.10-34). The clinical success rate was 67.2% six months after the surgery. The most frequent complications were: IOP spikes >30 mmHg (16.8%), improper position or angled drain (14.0%) and transient minimal hyphema (<1 week) (11.2%). During the follow-up, the needling was required in 34.6% of cases and a total of 10 eyes (9.4%) required a new glaucoma surgery. To conclude XEN implantation appears to be an effective short- and mid-term surgical technique to control IOP in OAG with a low risk of complication. However postoperative maneuvers were frequently required to maintain efficiency.


Asunto(s)
Glaucoma de Ángulo Abierto/cirugía , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Glaucoma de Ángulo Abierto/diagnóstico , Humanos , Presión Intraocular , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Procedimientos Quirúrgicos Mínimamente Invasivos/efectos adversos , Resultado del Tratamiento
5.
Vision Res ; 155: 1-10, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30571997

RESUMEN

People with central field loss (CFL) use peripheral vision to identify words. Eccentric vision provides ambiguous visual inputs to the processes leading to lexical access. Our purpose was to explore the hypothesis that this ambiguity leads to strong influences of inferential processes, our prediction being that increasing word frequency would decrease word reading time. Individuals with bilateral CFL induced by macular diseases read French sentences displayed with a self-paced reading method. Reading time of the last word of each sentence (target word) was recorded. Each target word (in sentence n) was matched with a synonym word (in sentence n+1) of the same length. When using absolute frequency value (Analysis 1), we found that reading time of target words decreased when word frequency increases, even when controlling for word length. The amplitude of this effect is larger than reported in previous investigations of reading with normal subjects. When comparing the effect of relative frequency (low vs. high) within each pair of synonyms (Analysis 2), results show the same pattern as the one observed in Analysis 1. Our results demonstrate clear-cut frequency effects on word reading time and suggest that inferential processes are stronger in CFL readers than in normally sighted observers. These results might also help design text simplification tools tailored for low-vision patients.


Asunto(s)
Degeneración Macular/fisiopatología , Degeneración Macular/rehabilitación , Lectura , Escotoma/fisiopatología , Baja Visión/fisiopatología , Campos Visuales/fisiología , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad
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