Paroxysmal alternating skew deviation and nystagmus after partial destruction of the uvula
- aMRC Human Movement and Balance Unit, The National Hospital for Neurology and Neurosurgery, Queen Square, London WC1N 3BG, UK, bNational Hospital for Neurology and Neurosurgery
- Dr P RudgeP.Rudge{at}ion.ucl.ac.uk
- Received 22 June 2000
- Revised 24 January 2001
- Accepted 14 February 2001
Abstract
A patient with suspected brain stem glioma involving the area of the left vestibular nuclei and cerebellar peduncle, developed paroxysmal alternating skew deviation and direction changing nystagmus after biopsy of the inferior cerebellar vermis resulting in destruction of the uvula. Between attacks she had right over left skew deviation with asymptomatic right beating horizontal nystagmus. Slow phases of the resting nystagmus showed increasing velocity, similar to congenital nystagmus. At intervals of 40–50 seconds, paroxysmal reversal of her skew deviation occurred, accompanied by violent left beating horizontal torsional nystagmus lasting 10–12 seconds and causing severe oscillopsia. It is proposed that this complex paroxysmal eye movement disorder results from (1) a lesion in the left vestibular nuclei causing right over left skew and right beating resting nystagmus and (2) a disruption of cerebellar inhibition of vestibular nuclei, causing alternating activity in the vestibular system with intermittent reversal of the skew deviation and paroxysmal nystagmus towards the side of the lesion.
