Infection of CNS spreads to the inner ear through which of the structures?

Cochlear aqueduct: connects scala tympani to CSF The labyrinth maintains connections with the central nervous system (CNS) and subarachnoid space by way of the internal auditory canal and cochlear aqueduct. Bacteria may gain access to the membranous labyrinth by these pathways or through congenital or acquired defects of the bony labyrinth.