China
Africa
Explore chapters and articles related to this topic
Ears
Published in Marie Lyons, Arvind Singh, Your First ENT Job, 2018
The facial nerve nucleus lies in the caudal part of the pons, and it loops around the abducens nucleus in the floor of the fourth ventricle. It emerges at the lower border of the pons with the nervus intermedins, and both travel to the internal auditory meatus along with the vestibulocochlear nerve. The facial nerve enters its bony canal above the vestibule of the labyrinth. At the first genu lies the geniculate ganglion, and the greater petrosal nerve leaves the main facial nerve at this point to supply the nasal and lacrimal glands. Taste fibres from the palate relay impulses in the opposite direction. The facial nerve proper turns posteriorly at this point, and the outline of its canal can be seen between the promontory and the lateral semicircular canal (seeFigure 1.3). Some branches leave the nerve at this point and join the tympanic plexus. The nerve eventually turns again, this time inferiorly medial to the aditus ad antrum to reach the stylomastoid foramen. The corda tympani leaves the facialnerve about 5-6 mm above the stylomastoid foramen to enter the middle ear. It runs over the pars flaccida between the malleus and the incus. It passes out of the middle ear anteriorly at the tympanic notch. It emerges from the petrotympanic fissure along the medial part of the spine of sphenoid and joins the lingual nerve. The corda tympani carries taste fibres from the anterior two-thirds of the tongue and secretomotor fibres to the floor-of-mouth salivary glands.
Head and Neck
Published in Rui Diogo, Drew M. Noden, Christopher M. Smith, Julia Molnar, Julia C. Boughner, Claudia Barrocas, Joana Bruno, Understanding Human Anatomy and Pathology, 2018
Rui Diogo, Drew M. Noden, Christopher M. Smith, Julia Molnar, Julia C. Boughner, Claudia Barrocas, Joana Bruno
The greater and lesser palatine nerves supply both the hard and soft palates and carry with them postganglionic parasympathetic fibers. Remember that the nerve of the pterygoid canal (Vidian nerve) enters the ptery-gopalatine fossa, is connected anteriorly to the pterygopalatine ganglion, and carries preganglionic parasympathetic axons from the greater petrosal nerve and postganglionic sympathetic axons from the deep petrosal nerve (Plates 3.20 and 3.39; described in detail in Section 3.3.1.5). The lesser palatine nerve and the greater palatine nerve carry these fibers from the pterygopalatine ganglion through the greater palatine canal and pass through the lesser and greater palatine foramina, respectively.
Specific Synonyms
Published in Terence R. Anthoney, Neuroanatomy and the Neurologic Exam, 2017
Greater petrosal nerve (W&W, p. 1071) Major superficial petrosal nerve (C&S, p. 386)
Reorganization of sensorimotor gating after peripheral facial palsy starts at brainstem*
Published in Neurological Research, 2018
Ayşegül Gündüz, Nurten Uzun, Feray Karaali-Savrun, Meral E. Kızıltan
Peripheral facial paralysis (PFP) is characterized by loss or reduced motor performance on one side of face. Thus, in PFP, motor pathway which functions in the production of facial expression is impaired. The electrophysiological findings also show smaller or delayed motor and facial reflex responses in the acute phase of PFP [2,3], whereas sensory pathways innervating facial structures are intact likely creating an imbalance in sensorimotor gating. There is a suggestion for direct involvement of trigeminal nerve. In a patient with typical PFP and unilateral numbness of face, contrast enhancement in the superficial greater petrosal nerve suggested an anatomical spread through the connection between facial and trigeminal nerves [4]. However, a thorough literature search reveals few papers suggesting trigeminal dysfunction after PFP. Trigeminal function in acute PFP within five days after the onset was abnormal in more than half of the patients and trigeminus-evoked potentials suggested a more central origin for trigeminal dysfunction in PFP [5]. Masseter inhibitory reflex, a trigemino-trigeminal reflex, was abnormal in a minority of PFP cases suggesting trigeminal involvement in certain cases, as well [6]. More recent works using functional magnetic resonance imaging in the acute phase of PFP showed stronger activation in the contralateral somatosensory association cortex along with increased activation in the contralateral primary motor cortex innervating facial muscles at rest [7] or increased activation in bilateral primary sensory and motor cortices during facial movement task and increased activation in contralateral primary sensory and motor cortices during facial sensory stimulation [8]. The ultimate opinion is that acute paralysis on one side of face leads to a profound and diffuse sensorimotor mismatch in the brain affecting the activities of bilateral cortical, striatal, and brainstem structures [8,9].