Contribution of Short-Time Occlusion of the Amblyopic Eye to a Passive Dichoptic Video Treatment for Amblyopia beyond the Critical Period.

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.

Risk factors associated with progression from papilloedema to optic atrophy: results from a cohort of 113 patients.

BACKGROUND: The aim of this study was to assess the risk factors for atrophic progression of patients with papilloedema secondary to intracranial hypertension, using optical coherence tomography parameters. METHODS: A retrospective study was conducted at Marseille University Hospitals' Ophthalmology departments between December 2015 and December 2021. All patients with papilloedema resulting from elevated intracranial hypertension at the initial presentation were included. Ophthalmological evaluations included analysing retinal nerve fibre layer (RNFL), ganglion cell layer (GCL) and total peripapillary retinal thickness (RT). RESULTS: The study included 222 eyes from 113 patients. The main aetiologies of intracranial hypertension were idiopathic intracranial hypertension (49/113), intracranial tumours (33/113) and cerebral venous thrombosis (15/113). The initial RNFL and RT showed significant correlations with optic atrophy. The mean RNFL was 199.63 µm in the 'no atrophy' group and 365.28 µm in the 'atrophy' group (p<0.001). Similarly, the mean RT was 483.72 µm in the 'non-atrophy' group and 796.69 µm in the 'atrophy' group (p<0.001). The presence of peripapillary haemorrhages showed a strong correlated with optic atrophy with an OR=19.12 (p<0.001). Impaired initial visual acuity was also associated with final optic atrophy with an OR=7.76 (p=0.020). Furthermore, impaired initial GCL was a major predictor of optic atrophy (OR=18.25 (p=0.021)). CONCLUSION: Our study highlights the risk factors for optic atrophy in papilloedema, aiming to facilitate the early detection of patients at a high risk of vision loss and enable more aggressive medical or surgical management.

Paracentral Acute Middle Maculopathy as a Specific Sign of Arteritic Anterior Ischemic Optic Neuropathy.

PURPOSE: The purpose of this study is to assess the diagnostic accuracy of paracentral acute middle maculopathy (PAMM) in the setting of anterior ischemic optic neuropathy (AION) to distinguish arteritic (A-AION) from nonarteritic (NA-AION) type. DESIGN: Retrospective cross-sectional diagnostic evaluation. METHODS: PAMM was evaluated by 3 physicians blinded to diagnosis using macular spectral-domain optical coherence tomography. We studied 45 patients with AION. Of those, 28 had NA-AION and 17 had A-AION. The study was conducted in the Department of Ophthalmology at the Hospital of Marseille-Assistance Publique, France, from January 1, 2018, to March 31, 2022. RESULTS: PAMM were only found in the A-AION group (N = 4) (P = .0143). As a distinctive sign of A-AION, we found a specificity of 100% (95% IC, 88.06%-100%) and a positive predictive value of 100%. In contrast, sensitivity and negative predictive value were lower, 19.1% (95% IC, 5.5-42.0) and 63.0% (95% CI, 58.1-67.7), respectively. CONCLUSIONS: The PAMM finding is highly specific for A-AION in the setting of AION. According to our results, macular spectral-domain optical coherence tomography looking for PAMM should be performed with any patient presenting with AION.

Human and Animal Dirofilariasis in Southeast of France.

Dirofilariasis is one of the oldest known zoonotic infections of humans mainly caused by the filarial parasites of the species Dirofilaria immitis and Dirofilaria repens, which primarily infect dogs. A five-year survey (2017 to 2021) was conducted among the dog population to assess the molecular prevalence of Dirofilaria spp. in southeast France. Morphological and genetic analysis were performed on filaroids from dogs and one infected woman from the studied area. A total of 12 (13%) dogs scored molecularly positive for Dirofilaria spp. of which nine carried blood microfilariae. Ocular dirofilariasis was detected in a 79-year-old woman with no travel history. Both electron microscopy and molecular sequencing identified the worm in the human case as D. repens. Molecularly, D. repens isolates were identical in the human and dog cases, representing the only genotype reported so far in France. Despite the distribution of this genotype through all Europe, it was grouped separately with the other two European genotypes and with Asian ones. As in almost all previous human cases in France, D. repens parasites were mainly recovered from the ocular region of patients and were geographically concentrated in the southeastern regions. Data demonstrate the sympatric occurrence of D. immitis and D. repens with high risk of infection to human and dog populations in these investigated geographical areas, thereby underlining the urgent need to implement preventive chemoprophylactic strategies and vector control to reduce the risk of these filaroids in dog and human populations.

The inhibitory effect of word neighborhood size when reading with central field loss is modulated by word predictability and reading proficiency.

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.

The influence of word frequency on word reading speed when individuals with macular diseases read text.

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.

Diffuse subretinal fibrosis syndrome: A rare entity.

BACKGROUND/ PURPOSE:: Diffuse subretinal fibrosis and uveitis syndrome is an inflammatory disease rarely reported. The purpose of this article is to describe a rare case of diffuse subretinal fibrosis syndrome in an 8-year-old child. METHODS AND RESULTS:: The patient initially presented with a loss of vision in his right eye, with a visual acuity of 20/200. The visual acuity of the left eye was normal. Clinical examination showed bilateral anterior and posterior inflammation while the fundus revealed on the right eye an inter maculopapillar fibrosed lesion with a discrete retinal hemorrhage and a similar but smaller lesion on the left eye. The optical coherence tomography showed hyper-reflective material compatible with pre-retinal and subretinal pigment epithelial fibrosis and associated subretinal fluid. The angiography facilitated the diagnosis of neovascularization that was associated with the fibrotic lesion. The rest of the clinical pediatric examination remained negative and a diagnosis of diffuse subretinal fibrosis syndrome complicated with neovascularization was made. Treatment with systemic corticosteroids at the dose of 1 mg/kg/day for 1 month with a progressive decrease of 5 mg per month allowed for both anatomical and functional improvement. The visual acuity of the right eye improved from 20/200 to 20/63 at 1 month, 20/32 at 2 months, and 20/20 at 4 months. CONCLUSION:: To our knowledge, this is the first reported case of bilateral diffuse subretinal fibrosis complicated by neovascularization. General corticosteroid therapy proved to be effective in this case and appears to be a viable option in first-line treatment.