Visual impairment (or vision impairment) is vision loss (of a person) to such a degree as to qualify as an additional support need through a significant limitation of visual capability resulting from either disease, trauma, or congenital or degenerative conditions that cannot be corrected by conventional means, such as refractive correction, medication, or surgery. The phenotype is Human Phenotype Ontology id HP_0000505 (Visual impairment). Also known as: Impaired vision, Loss of eyesight, Poor vision.