· To describe with imaging, the normal anatomical course of facial nerve · To describe the common pathological signs on MRI or HRCT

The facial nerve is a mixed cranial nerve with motor, parasympathetic, and sensory branches. Course of Facial nerve The intraaxial segment is located within the brainstem and consists of the motor nucleus, superior salivary nucleus (parasympathetic), and nucleus of tractus solitarius (sensory). The cisternal segment consists of the motor root and nervus intermedius (nerve of Wrisberg). Both the motor root of the facial nerve and the nervus intermedius(nerve of Wrisberg) leave the brainstem near the dorsal pons at the pontomedullary junction (the cisternal segment of...

PATHOLOGIES AFFECTING FACIAL NERVE Oval window stenosis/atresia The intimate relationship between formation of the oval window and development of the stapes footplate, horizontal segment of the facial nerve canal, and vestibular portion of the otic capsule results in commonly associated anomalies, including facial nerve malposition and incus and stapes malformations. Facial nerve schwannoma(FNS). FNSs usually involve more than one segment of the FN. Like schwannomas occurring elsewhere, FNSs are typically fusiform solid tumors with well-circumscribed smooth margins. They usually grow along the path of least...

Imaging of facial nerve and comparing variations with the normal anatomical course helps in a great deal in identifying lesions along its course. Depending on the segment to be visualized CT and MRI have complimentary roles in identifying facial nerve pathology.

Dr. I . Gurubharath MD Ph.D Professor & HOD Department of Radiodiagnosis Velammal Medical College Hospital & Research Institute Velammal,Madurai Tamil Nadu – 625009, India. E-mail: [email protected] Dr. Fraser Gomes Postgraduate resident Department of Radiodiagnosis Shri Sathya Sai Medical College and Research Institute Chennai, Tamil Nadu – 603108 India E-mail: [email protected] Dr. Harshavardhan Balaganesan Senior resident Department of Radiodiagnosis Shri Sathya Sai Medical College and Research Institute Chennai, Tamil Nadu – 603108 India E-mail: [email protected]

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