·396·PARTVINERVOUSSYSTEMLacrimal nFrontal n.Frontal sincusLacrimal glandIrisOphthalmicnpupil山Trigiminal gangliosensoryrooMaxillarMandibularn.Infraorbital n.Fig. VI-5-22 The nerves within the orbit(lateral view)SupratrSupraorbital n.InfratrochleFrontal n.NasociliaryLacrimalnTrochleOphthalmicn.Internal carotid aMaxillary n.OpticnMandibularn.rigeminal ganglionOculomotoFig. VI-5-23 The nerves within the orbit(superior view)of the bulbopontine sulcus. After leaving the surfaceof the brain stem, the abducent nerve runs forward3.9Abducent nerve (CNVI)and laterally, crosses the apex of the petrous part ofthe temporal bone. It then traverses the cavernous si-Abducent nerve is very thin and supplies the lat-nus (Fig. VI -5-19, 22, 24), lateral to the internal ca-eral rectus of eye only. It arises from the abducentrotid artery, and enters the orbital cavity through thenucleus in the pons and emerges from the medial part扫描全能王创建
Chapter 5 Peripheral Nervous System · 397 :it. The result of the damage of abducent nerve is thesuperior orbital fissure.Finally the nerve enters intoparalysis of the lateral rectus and medial squint.the medial surface of the lateral rectus and supplies1Anterior cerebral Opticn.IntermalcarotidaOculomotornCavernous sinusAbducentnTrigeminal ganglionPosterior cerebral aSuperior cerebellaRootoftrigeminal n.Superior petrosal sinusSubstantia nigraTrochlear n.Red nucleusMidbrainFig.VI-5-24 The nerves passing through the cavernous sinussupply it.Unilateral lesionofaccessorynerveusually doesAccessory nerve(CN XI)not produce an abnormality in the position of thehead. However, weakness in turning the face to theIt is a special visceral motor nerve, formed by theopposite side can be detected due to the stermocleido-union of the cranial and spinal roots.The smaller cra-mastoid paralysis.Unilateral paralysisofthe trapeziusnial root arises from the lower part ofthe nucleus am-mayproduce dropping of the shoulder.In fracturesbiguus and emerges from the posterior olivary sulcusor other injury involving the jugular foramen, theof the medulla below the rootlets of the vagus nerveglossopharyngeal, vagus and accessory nerves mayby 4-5 rootlets. The cranial root passes through thebe damaged together. The symptoms and signs of thisjugular foramen and joins the vagus nerve immediate-condition is called the jugular foramen syndrome orly to supply the muscles of the pharynx and the lar-Vernetsyndrome.ynx. The larger spinal root arises from the accessorynucleus in the anterior horn of the upper 5-6 cervical5.Hypoglossalnerve(CN XIl)segments of spinal cord. It emerges from the spinalcord by rootlets between the anterior and posteriorThe hypoglossal nerve is a somatic motor nerverootlets of the spinal nerves. The spinal root ascendsand arises from the hypoglossal nucleus (Fig. VI -2-22).and enters the skull throughtheforamen magnumIts 10-15 rootlets emerge from the anterior side of me-unites the cranial root to form the accessory nerve(Fig. VI-5-25). It then passes upward and laterally todulla oblongata between the olive and the pyramid bythe jugular foramen, where it passes backward andway of a number rootlets.The rootlets unite to leavedownward to the neck. After emerging out the spinalthe skull through the hypoglossal canal. The nerverootgoesto the sternocleidomastoid,which it piercesdescends between the internal carotid artery and the.internal jugular vein. At the level of the angle of theand supplies, and then crosses the posterior triangle ofmandible it passes forward over the internal and ex-the neck to enter the deep surface of the trapezius and扫描全能王创建