Cortical blindness is the total or partial loss of vision in a normal-appearing eye caused by damage to the brain's occipital cortex. Cortical blindness can be acquired or congenital, and may also be transient in certain instances. Acquired cortical blindness is most often caused by loss of blood flow to the occipital cortex from either unilateral or bilateral posterior cerebral artery blockage (ischemic stroke) and by cardiac surgery. In most cases, the complete loss of vision is not permanent and the patient may recover some of their vision (Cortical visual impairment). Congenital cortical blindness is most often caused by perinatal ischemia stroke, encephalitis and meningitis. Rarely, a patient with acquired cortical blindness may have little or no insight that they have lost vision, a phenomenon known as Anton's Syndrome or Anton-Babinski syndrome.
Cortical blindness and cortical visual impairment (CVI), which refers to the partial loss of vision caused by cortical damage, are both classified as subsets of neurological visual impairment (NVI). NVI and its three subtypes—cortical blindness, cortical visual impairment, and delayed visual maturation—must be distinguished from ocular visual impairment in terms of their different etiologies and structural foci, the brain and the eye respectively. One diagnostic marker of this distinction is that the pupils of individuals with cortical blindness will respond to light whereas those of individuals with ocular visual impairment will not.
Other articles related to "cortical blindness, blindness, cortical":
... The prognosis of a patient with acquired cortical blindness depends largely on the original cause of the blindness ... In patients with acquired cortical blindness, a permanent complete loss of vision is rare ... The development of cortical blindness into the milder cortical visual impairment is a more likely outcome ...
... in people under 30, are the leading cause of monocular blindness (vision loss in one eye) throughout the United States ... Cortical blindness results from injuries to the occipital lobe of the brain that prevent the brain from correctly receiving or interpreting signals from the optic nerve ... Symptoms of cortical blindness vary greatly across individuals and may be more severe in periods of exhaustion or stress ...
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