In considering preservation of the nerves to the frontalis muscle, the frontotemporal scalp flap is divided at the STL into lateral and medial parts. Surgical decompression may be proposed when the vasculo-nervous conflict is detected. As a result, visual defects may be the earliest evidence of general nervous system disease. Additionally, fractures to the stylohyoid bone, petrous temporal bone, or ramus of the mandible can damage the facial nerve. It is abolished if there is a lesion located upstream or on the stapedius nerve origin on the mastoid portion of the facial nerve. CN VIIb is theoretically separated although in close contact with the facial nerve in the cisterne and separation is not possible, including in post-surgery.
Facial Nerve (CN VII) Anatomy & Function
It is easily identified on the axial sections by MRI Figure 1. There are many branches, which transmit a combination of sensory, motor and parasympathetic fibres. What do you suspect are the main aetiologies? Create account or Sign in. CN VII exits the ventrolateral surface of the pons along with fascicles of the nervus intermedius, which contains the facial nerve sensory fibers and the visceral efferent fibers see Parasympathetic Pathways later in the chapter.
Facial nerve: From anatomy to pathology - EM|consulte
Recommended for You The Parotid Gland. Branches of the facial nerve are responsible for innervating many of the muscles of the head and neck. The facial nerve exits the skull behind the ear at stylomastoid foramen and enters the core of a salivary gland in front of the ear parotid gland. The course of the facial nerve is very complex. Description of natural brain boosters? It is bilaterally projected on the upper part of the nucleus controlling the muscles of the upper face and only contralaterally for the lower part of the face accounting for the predominant impairment on the lower face in case of facial nerve paralysis of central origin. Along its inch-and-a-half course through a small canal within the temporal bone, the facial nerve winds around the three middle ear bones, in back of the eardrum, and then through the mastoid the bony area behind the part of the ear that is visible.
Head deep facial and trigeminal nerves Georg Graf von Westphalen. The layers of the scalp medial to the STL are the skin and subcutaneous tissues, the galea, loose areolar tissue, and the frontal pericranium. Several series have shown that the most common location for schwannomas of the facial nerve is the geniculate ganglion. Above and medial to the level of the STL, the facial branches coursed in the loose areolar tissue between the galea and frontal pericranium Fig. World Neurosurgery , Meatal segment The nerve pass in the petrous bone in the anterosuperior quadrant of the fundus of the meatus.