Intracranial (cisternal) segment of facial nerve

The intracranial segment of facial nerve (cisternal segment of facial nerve; F1) comprises the two roots (motor root and sensory root/nervus intermedius) of the facial nerve that emerge from the lower lateral pons. These two roots pass through the posterior cranial fossa in the cerebellopontine angle, medial and caudal to the vestibulocochlear nerve (CN VIII), and finally enter the internal acoustic meatus in the temporal bone.