Cortical visual impairment in children

Novel genetic causes for cerebral visual impairment

“…Deficits in higher perceptual functions, for example, difficulties with recognition of objects and faces, or visio-spatial disorders can occur and are sometimes the only features of CVI. [3][4][5] CVI can occur in isolation, but more often additional features are present, such as intellectual disability (ID), epilepsy and/or deafness. [6][7][8] An important cause of CVI is acquired damage to the brain, mainly the result of perinatal problems (eg, cerebral hemorrhage or periventricular leukomalacia), but also other types of acquired damage, such as congenital infection, hypoglycemia, meningitis, or head trauma, can be causal.…”

Visual function in the brain-damaged child

“…49,50,52,53 First and foremost, total absence of sight in children caused by a bilateral disturbance of the optic radiations and/or calcarine cortex is extremely rare. 50,[54][55][56][57][58][59][60] Moreover, unlike the case in adults, significant visual recovery can be documented in a large proportion of the children with visual loss caused by calcarine cortex injury. Roland et al 56 studied 30 children with visual loss caused by occipital cortex injury and documented some degree of visual recovery in 50%.…”

“…Optic atrophy has been noted in other studies of cortical visual impairment in children. 54,57,151,152 Whether this results from trans-synaptic degeneration of optic axons as a result of bilateral damage to the striate cortex and/or optic radiations, as some others have suggested, 57,151 will be discussed in the next section. In any case, when present, optic atrophy obviously adds to the visual disability of the child with cortical visual impairment.…”

“…50 Yet, most investigators who study these children seem to believe that some unique mechanism of plasticity of the brain in infants is an important factor in the apparent visual recovery that occurs in many of these children. 51,54,55,62 In order to understand what mechanisms may account for this apparent plasticity of infant visual brain, it is important to detail both our current understanding of adult recovery mechanisms involved in visual cortex injuries and the recent animal models that have specifically addressed infant visual cortex ablation.…”

Subnormal visual perception in school-aged ex-preterm patients in a paediatric eye clinic

“…Vision may be variable, and paradoxes in visual behaviour that are difficult to understand are common. [12][13][14][15] Visual perceptual problems may cause serious visual impairment despite good VA and normal visual fields.…”