Does posterior fossa decompression improve oculomotor and vestibulo-ocular manifestations in Chiari 1 malformation?
GROUND: Oculomotor and vestibulo-ocular manifestations are associated with Chiari 1 malformation. Reports of the results of decompression of CM1 in resolution of these manifestations are limited. METHODS: A retrospective review of case notes were undertaken from Jan 1998 to March 2003 of all the cases undergoing posterior fossa decompressions by the senior author. Forty patients were identified of which 12 had oculomotor and vestibulo-ocular manifestations. RESULTS: Oculomotor and vestibulo-ocular symptoms were present in seven patients and eleven patients had clinical signs. There were only 2 patients who had symptoms and no objective findings. There was complete resolution of oculomotor and vestibulo-ocular manifestations in 8/12 patients and partial improvement in another one, leading to improvement in 9/12 patients. The mean time span to complete resolution was 15.5 months (range 3-71 months). CONCLUSION: Posterior fossa decompression appears to be highly effective in causing compl