Leptomeningeal dissemination of low grade glial tumours is a rarely reported occurrence and is most often associated with a history of prior surgical intervention. We report a unique case of leptomeningeal dissemination of a pilocytic astrocytoma, WHO grade 1, in a 47-year-old male occurring prior to the time of initial diagnosis. To our knowledge this has not previously been reported in an adult patient. The initial lesion was identified in the trigone of the right lateral ventricle which is an unusual location for pilocytic astrocytoma. Following the initial diagnosis, an MRI of the neural axis was performed revealing a second intradural lesion located at S2 level. Resection specimens from both lesions showed similar histology consistent with pilocytic astrocytoma, WHO grade 1. The clinical and pathological features of this case will be discussed with a review of the literature.