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BACKGROUND: Cortical visual impairment (CVI) is a verifiable visual dysfunction that cannot be attributed to disorders of the anterior visual pathways or any potentially co-occurring ocular impairment. Given the limited knowledge on the most effective interventions for visual impairment resulting from CVI, this case report provides valuable insights into an example of successful implementation of anti-amblyopia therapy in a patient with CVI.
METHODS: This case report presents a 5-year-old girl with CVI secondary to hypoxic-ischemic injury, resulting in visual impairment, dyspraxia, and abnormal visual evoked potential testing. The girl did not suffer from amblyopia, there was no evidence of relevant refractive errors or strabismus, so visual pathway damage was the cause of her visual deficit. Nevertheless, the patient underwent anti-amblyopia therapy and showed significant improvement in visual acuity after 12 months of treatment. The improvement, resulting from visual stimulation, was due to a good functional recovery by a better usage of the damaged visual pathways. The therapy included prescribing corrective glasses and implementing secondary occlusion of the better eye for 4 months, which was protracted for another 4 months, leading to further improvements in visual acuity.
CONCLUSIONS: The case report shows that addressing even minor refractive errors and implementing anti-amblyopia therapy can significantly improve vision in children with CVI, even without co-existing amblyopia. It also highlights the importance of early intervention and multidisciplinary rehabilitation in children with CVI, focusing on motor and cognitive skills. Additionally, it emphasizes the need for further research to establish evidence-based practice standards for improving vision in children with CVI.

Many complications but cortical blindness after percutaneous vertebroplasty has been rarely reported. Here, we describe a case who developed cortical blindness after percutaneous vertebroplasty. We also reviewed the literature to find the possible causes of this complication and its treatment.
Case report and literature review.
A 71-year-old woman experienced cortical blindness after percutaneous vertebroplast. She developed dizziness, nausea, sweating, blood pressure changes, and vision loss during the procedure. MRI confirmed bilateral cerebral infarctions. The patient recovered with conservative treatment.
Percutaneous vertebroplasty, though helpful, carries a rare risk of cortical blindness. Surgeon awareness is crucial for informing patients of this potential complication.

OBJECTIVE: According to a seminal hypothesis stated by Crick and Koch in 1995, one is not aware of neural activity in primary visual cortex (V1) because this region lacks reciprocal connections with prefrontal cortex (PFC).
METHODS: We provide here a neuropsychological illustration of this hypothesis in a patient with a very rare form of cortical blindness: ventral and dorsal cortical pathways were lesioned bilaterally while V1 areas were partially preserved.
RESULTS: Visual stimuli escaped conscious perception but still activated V1 regions that were functionally disconnected from PFC.
CONCLUSIONS: These results are consistent with the hypothesis of a causal role of PFC in visual awareness.

BACKGROUND: Cerebral visual impairment (CVI) is the most common form of paediatric visual impairment in developed countries. CVI can arise from a host of genetic or acquired causes, but there has been limited research to date on CVI in the context of genetic disorders.
METHODS: We carried out a retrospective analysis of genotypic and phenotypic data for participants with CVI within the DECIPHER database and 100 000 Genomes Project (100KGP).
RESULTS: 158 individuals with CVI were identified across both cohorts. Within this group, pathogenic or likely pathogenic sequence variants in 173 genes were identified. 25 of these genes already have known associations with CVI, while the remaining 148 are candidate genes for this phenotype. Gene ontology analysis of the CVI gene sets from both DECIPHER and 100KGP suggests that CVI has a similar degree of genetic heterogeneity to other neurodevelopmental phenotypes, and a strong association with genetic variants converging on ion channels and receptor functions. Individuals with a monogenic disorder and CVI have a higher frequency of epilepsies and severe neurodisability than individuals with a monogenic disorder but not CVI.
CONCLUSIONS: This study supports the availability of genetic testing for individuals with CVI alongside other neurodevelopmental difficulties. It also supports the availability of ophthalmological screening for individuals with genetic diagnoses linked to CVI. Further studies could elaborate on the links between specific genetic disorders, visual maturation and broader neurodevelopmental characteristics.

The existence of unconscious visually triggered behavior in patients with cortical blindness (e.g., homonymous hemianopia) has been amply demonstrated and the neural bases of this phenomenon have been thoroughly studied. However, a crosstalk between the two hemispheres as a possible mechanism of unconscious or partially conscious vision has not been so far considered. Thus, the aim of this study was to assess the relationship between structural and functional properties of the corpus callosum (CC), as shown by probabilistic tractography (PT), behavioral detection/discrimination performance and level of perceptual awareness in the blind field of patients with hemianopia. Twelve patients were tested in two tasks with black-and-white visual square-wave gratings, one task of movement and the other of orientation. The stimuli were lateralized to one hemifield either intact or blind. A PT analysis was carried out on MRI data to extract fiber properties along the CC (genu, body, and splenium). Compared with a control group of participants without brain damage, patients showed lower FA values in all three CC sections studied. For the intact hemifield we found a significant correlation between PT values and visual detection/discrimination accuracy. For the blind hemifield the level of perceptual awareness correlated with PT values for all three CC sections in the movement task. Importantly, significant differences in all three CC sections were found also between patients with above-vs. chance detection/discrimination performance while differences in the genu were found between patients with and without perceptual awareness. Overall, our study provides evidence that the properties of CC fibers are related to the presence of unconscious stimulus detection/discrimination and to hints of perceptual awareness for stimulus presentation to the blind hemifield. These results underline the importance of information exchange between the damaged and the healthy hemisphere for possible partial or full recovery from hemianopia.

Visual anosognosia, associated with confabulations and cortical blindness in the context of occipital lobe injury, is known as Anton syndrome. Patients with this syndrome strongly deny their vision loss and confabulate to compensate for both visual loss and memory impairments. In this article, we present a case of a patient with some similarities to Anton syndrome, however, with several differences in clinical presentation. Bifrontal brain injury, bilateral enucleation, affective indifference (anosodiaphoria), generalized anosognosia, and the conviction that vision will resume mark clear clinical differences with Anton syndrome. Differentiating these findings from Anton syndrome will help occupational therapists, neuropsychologists, speech-language pathologists, physical therapists, and physicians when assessing frontal lobe brain injury with total and partial visual loss. This case demonstrates that visual anosognosia and confabulations can occur without occipital lobe dysfunction or cortical blindness.

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BACKGROUND: Contrast-induced Neurotoxicity (CIN) is an increasingly recognised complication following endovascular procedures. It remains a relatively unexplored clinical entity, and we sought to characterise clinician perspectives towards CIN, as well as identify gaps in knowledge and provide directions for future research.
METHODS: An online survey was distributed to members of the Australian and New Zealand Society of Neuroradiology, as well as several Australian tertiary hospitals. Questions related to clinical exposure to CIN, diagnosis, management and pathophysiology were explored. Descriptive analysis was conducted on survey responses, and statistical analysis was performed using Chi-square and Fisher\'s exact test as appropriate.
RESULTS: A total of 95 survey responses were recorded (26.8% response rate). Only 28.4% of respondents were comfortable in diagnosing CIN, and even fewer (24.2%) were comfortable in independently managing CIN patients. Based on clinician opinion, symptoms including impaired consciousness and cortical blindness were thought to be most associated with CIN, whilst the radiological findings of parenchymal oedema and cortical enhancement were considered to be most indicative of CIN. Most clinicians agreed that further investigation is required related to pathophysiology (86.3%), diagnosis (83.2%), and treatment (82.1%).
CONCLUSIONS: CIN is a poorly understood complication following endovascular procedures. Significant gaps in clinical understanding are evident, and further investigation is vital to improve diagnosis and management.

Cerebral visual impairments have been of great interest to neurologists, ophthalmologists, and neuroscientists. Complicated or partial varieties related to cortical blindness are discussed in this review. They are a fascinating alphabet of eponymic clinical syndromes, bordering neurology, ophthalmology, and even psychiatry. Recent functional imaging and experimental studies have contributed further knowledge of cognitive visual organization in addition to the classical lesion evidence.