Relationship between Signal Intensity of the Labyrinth and Cochleovestibular Testing and Morphologic Features of Vestibular Schwannoma.

The aim of this article was to evaluate the relationship between signal intensity of the labyrinth and vestibulocochlear function and morphologic features of vestibular schwannoma (VS).  Cross-sectional Study.  Tertiary referral center.  Fifty-four patients with sporadic, untreated VS.  Signal intensity of the cochlea and vestibule (SIRc and SIRv: signal intensity of cochlea/vestibule compared with cerebellar signal intensity; AURc and AURv: SIRc/SIRv of the affected side compared with the unaffected side) in 1.5T T2-weighted images was correlated with size (Hannover classification), cystic status, distance from the fundus of the internal auditory canal, video head impulse test (vHIT), and audiometry.  Signal intensity of the vestibule was higher than that of the cochlea (  < 0.01). Large tumors had lower SIRc than smaller tumors (  = 0.03); Hannover T1 tumors had higher SIRc (  < 0.01), SIRv (  < 0.01), AURc (  < 0.01) and AURv (  < 0.01) than the rest; heterogenous and cystic tumors had higher SIRv than solid large tumors (  = 0.02); superior vestibular nerve pattern on vHIT had higher SIRv and AURv than inferior vestibular nerve and mixed patterns (  = 0.03 and 0.004, respectively); and there was a weak correlation between AURv and speech discrimination (  = 0.33,  = 0.04).  A more abnormal signal intensity of the labyrinth is associated with larger size and solid status of VS. There was a positive relationship between signal intensity of the labyrinth and speech discrimination scores on audiogram.