vision impairment的用法和样例：
例句
- Age-related macular degeneration is the leading cause of visual impairment and blindness among the old people.
老年性黄斑变性是老年人最主要的视力损伤和致盲原因之一。 - Optic nerve avulsion is a rare globar injury, which usually results in permanent and devastating loss of vision.
摘要视神经撕除是一种罕见的伤害，这种伤害通常会造成永久且严重的视力损伤。
