Abstract:

Aim. The purpose of the study was to improve the MRI visualization of cranial nerves (CN) in normal state and in different pathological conditions. Tasks. Our tasks were to develop MRI protocols for CN visualization, describe MRI anatomical features of CN, and MRI symptoms of different CN involvement

Materials and methods. High field MRI was done in 252 patients, with 498 high quality images of CN. There were 202 patients with CN pathology, and 50 volunteers without CN involvement symptoms. Imaging was performed with «Signa Infinity» 1,5 Tl (General Electric). MRI protocol included 2 stages: basic for brain imaging, and special for CN visualization.

Results. The majority of the patients (112) had trigeminal nerve involvement, 51 - vestibulocochlear nerve, 16 - facial nerve, 9 - optic nerve, 5 - trochlear nerve, 4 - caudal CN involvement, 3 - olfactory nerve, 1 - oculomotor nerve, and 1 patients with abducent nerve disfunction. The etiology was vascular in 133 cases, tumorous in 45, demyelinating in 14, inflammatory and infection in 7, and congenital anomalies in 2 patients.

Conclusions. MRI is suitable for CN anatomical visualization and differentiation; the method is able to identify the level of CN involvement and surrounding tissues reaction. MRI protocol should include two steps - basic and special, the latter depending on the particular CN involvement.
 

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