[Neuro-otological manifestations as presentacion of type I Chiari malformation]

The type I Chiari malformation consists of an caudal descent of the cerebellar tonsils through the foramen magno towards the spinal cervical channel. The usual clinical presentation are occipital headaches and cervical pain, as well as some otoneurological symptoms. Among them are common dizziness and crisis of central positional vertigo in which down beating nystagmus can be observed. We present our experience with three cases presenting with neurotological manifestations in which MRI showed a type I Chiari malformation. Case 1: a patient of 24 years that had frequent instability, and common crisis ofpositional vertigo. It was possible to see the presence of positional down-beating nystagmus, of central characteristics, that improved after neurosurgical treatment. Case 2: patient of 11 years who suffered from occasional headaches, dizziness and positional vertigo, without severe handicap, and did not need surgery. Case 3: lady of 63 years who had common episodes of vertigo with head tilt, and unsteadiness during walks. Due to the coexistence of hydrocephalus and syringomyelia, surgery was indicated. A revision is done on otoneurological presentation of type I Chiari malformation, especially as differential diagnosis on central positional vertigo.