Diagnosis of Vestibular Neuronitis Audiology, electronystagmography, and MRI If clinicians suspect vestibular neuronitis, tests should include an audiologic assessment, electronystagmography with caloric testing, and gadolinium-enhanced MRI of the head, with attention to the internal auditory canals to exclude other diagnoses, such as cerebellopontine angle tumor, brain stem hemorrhage, or infarction.