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What is Spontaneous veical nystagmus is seen in the lesion of and explain in detail?
Veical downbeat nystagmus indicates lesion at craniocervical region such as Arnold-Chiari malformation or degenerative lesion of the cerebellum. Veical upbeat nystagmus is seen in lesions at the junction of pons and medulla or pons and midbrain. Ref: Dhingra 7e pg 43.