Figure 2.

Progressive contrast diffusion within the cochlea and vestibule

Two patients (P1 and P2) demonstrated variable initial contrast uptake into the cochlea at 1 h on T1-weighted SPACE fat-saturated (FS) MRI after intrathecal gadolinium contrast administration. Contrast is initially observed in the basal turn (red arrow) of the cochlea (P1) and not the cochlear apex (yellow arrow) nor vestibule (dashed circle). P2 exhibited more intense contrast uptake through the cochlea and initial vestibule uptake. On delayed imaging, contrast is seen throughout the cochlea and vestibule and semicircular canals. The blue arrow indicates contrast within the cochlear aqueduct, where contrast does not macroscopically connect to the basal turn of the cochlea.