颈静脉孔区解剖

颈静脉孔的应用解剖陈立华CHINA-INI•颈静脉孔由颞骨岩部和枕骨颈突围成。颞骨和枕骨向孔内的突起分别被称为颞突和枕突，二者以纤维或骨桥连接，构成孔内神经和血管的分隔。由颞突下方沿颈静脉球内侧缘伸向后方的骨性隆起称为颈内嵴，舌咽神经行于其内侧。•颈静脉孔为一自颅后窝通向前、外、下方的骨性管道。•颈静脉管（jugularcanal）。osseousrelationships,superiorview•osseousrelationships,posterosuperiorview.Thejugularforamenisbestseeninaposterosuperiorvieworientedperpendiculartotheclivus.•thejugularforamenislocatedbetweenthetemporalandoccipitalbones•sigmoidgroovedescendsalongthemastoidandcrossestheoccipitomastoidsuture,turnsforwardontheuppersurfaceofthejugularprocess,enterstheforamen•fromposteriorandsuperiorshowstheshapeoftheforamen•hypoglossalcanalpassesabovethemiddlethirdoftheoccipitalcondyleandopenslaterallyintotheintervalbetweenthejugularforamenandcarotidcanal•stylomastoidforamenislocatedlateralandtheanteriorhalfoftheoccipitalcondylemedialtothejugularforamen•anteriorandbackwardrevealstheshapeofthejugularforamen•largerlateralpart,thesigmoidpart,whichreceivesthedrainageofthesigmoidsinus,andasmallermedialpart,thepetrosalpart,whichreceivesthedrainageoftheinferiorpetrosalsinus•enlargedview•intrajugularprocessprojectsintotheintervalbetweenthesigmoidandpetrosalpartsoftheforamen•intrajugularridge,extendsforwardfromtheintrajugularprocessalongthemedialsideofthejugularbulb•cochlearaqueductopensabovethepetrosalpartoftheforamen,wheretheglossopharyngealnerveenterstheintrajugularpartoftheforamenonthemedialsideoftheintrajugularprocess.•thevestibularaqueductopensontotheposteriorsurfaceofthetemporalbonesuperolateraltothejugularforamen•Theinferiorpetrosalsinusextendsalongthepetroclivalfissureandentersthepetrosalpartoftheforamen•posterosuperiorviewoftheintrajugularprocessandridge,whichseparatethesigmoidandpetrosalpartsofthejugularforamenRembrandtvanRijn(Dutch,1606-1669).ThispaintingiscalledTheAnatomyLectureofDr.NicolaesTulp,paintedin1632颈静脉孔的硬膜结构及分部•Hovelacque将颈静脉孔分为前内侧的神经部和后外侧的血管部两部分。•Katsuta根据通过颈静脉孔的结构将其分为岩部、颈内部（或神经部）和乙状窦部。•神经部的硬膜形成舌咽道和迷走道，分别有舌咽神经和迷走神经及副神经穿过。舌咽道和迷走道位于颈内突内侧,二者间隔以0.5-4.9mm宽的硬膜。•神经部上外侧缘的硬膜返折增厚并伸向下内覆于舌咽道和迷走道上方，称颈静脉孔硬膜返折,是辨认颅神经的重要标志。•sigmoidsinusdescendsinthesigmoidsulcus,sharpanteriorturntoenterthejugularforamen.Thejugularbulbextendsupwardunderthepetroustemporalbonetowardtheinternalacousticmeatusnervespenetratetheduraonthemedialsideoftheintrajugularprocess,intrajugularridgeextendsforwardalongthemedialsideofthejugularbulbglossopharyngealnervepassesforwardalongthemedialsideoftheintrajugularridgevagusandaccessorynerves,onthemedialsideoftheintrajugularprocessvagusandaccessorynervespasslateraltotheosseousbridgeandtheinferiorpetrosalsinusdescendsbelowthebridgetoopenintotheinternaljugularveinhypoglossalcanalandjoinstheglossopharyngeal,vagus,andaccessorynervesbelowthejugularforamenintheintervalbetweentheinternalcarotidarteryandinternaljugularveinarachnoidopenedtoexposetheglossopharyngeal,vagus,andaccessorynervesenteringtheduraandpassingthroughtheintrajugularpartoftheforamen.Aduralseptumseparatestheglossopharyngealnervefromtheuppervagalrootletsatthesiteatwhichthenerveenterstheintrajugularportionoftheforamen.Thejugularduralfoldprojectsoverthenervesastheypenetratethedura•upperportionofthecerebellopontineangle,includingthetrigeminalnerves,hasbeenexposed•Abridgingveinpassesfromthemedullatothejugularbulb.Theposteroinferiorcerebellararterypassesbehindthehypoglossalnerveandbetweentheaccessoryrootlets颈静脉孔区神经定位•舌咽神经的根丝位于小脑绒球和Luschka孔脉络丛的前方，且位置关系相对恒定。因此，可将小脑绒球和Luschka孔脉络丛复合体作为辨认舌咽神经脑池段起始部的解剖标志，并据此初步判断迷走神经、副神经脑干端。•LachmanN研究发现副神经没有颅根，仅由脊髓根构成，颈静脉孔内副神经和迷走神经间无任何连接。均可在显微镜下纵行切开神经鞘膜，将神经束彼此分开。•A：Lateralviewofthenormalanatomyofthejugularforamen.•B：Axialcut(dottedlineinA)viewedfrominferiortothenormalanatomy.Notethattheperforationsconnectingtheinferiorpetrosalsinustothejugularveinrunbetweenthelowercranialnerves.•在颈静脉孔内口，舌咽神经根丝汇合后经单独的硬膜通道（舌咽道）入颈静脉孔，迷走神经和副神经则经迷走道入颈静脉孔。颈静脉孔神经部上外侧缘的硬膜返折增厚并唇样伸向下内覆于舌咽道和迷走道上方，即颈静脉孔硬膜返折，是于颈静脉孔内口辨认脑神经的标志。神经血管结构的位置关系•小脑后下动脉行程迂曲，与Ⅸ、Ⅹ、Ⅺ及Ⅻ对脑神经根关系复杂，其穿行脑神经根丝的形式，大致可分为四种：发自第一齿状韧带周围的小脑后下动脉穿副神经根丝；起自舌下神经孔周围者穿迷走神经和副神经根丝或之间；起自舌下神经孔与桥延沟之间者穿迷走神经根；起自基底动脉者勾绕舌咽神经和颈静脉孔。小脑后下动脉或/和迂曲的椎动脉压迫舌咽神经根被认为是引起舌咽神经痛的原因之一；小脑后下动脉或/和迂曲的椎动脉压迫延髓左侧可能引起血压升高，压迫延髓右侧可引起血糖升高。颈静脉孔区不同性质肿瘤的生长方式及特点，对术前正确诊断、确定合理的治疗方案及术中保护神经功能具重要意义颈静脉孔诊断神经鞘瘤神经鞘瘤起源于舌咽神经、迷走神经、副神经或颈交感干，沿其起源的神经生长。神经鞘瘤因压迫性溶骨致颈静脉孔扩大，表现为扇贝样改变而骨皮质完好。边缘常是光滑的，瘤边界清楚。容易发生囊变/坏死，肿瘤质地不均匀，内部多有短T1长T2的片状影。ＭＲＩ增强后肿瘤实质部分可强化，但不如脑膜瘤和化学感受器瘤明显。瘤内无流空的血管影可同化学感受器瘤鉴别，而ＭＲＩ上可显示面听神经也可同听神经瘤相鉴别。脑膜瘤•起源于颈静脉球或邻近静脉窦部的蛛网膜颗粒。Sekhar将颈静脉孔区脑膜瘤定义为附着于颈静脉孔硬膜或起源于延髓小脑角伴或不伴向颅外生长。•CT为高密度肿瘤。•MRI缺乏象化学感受器那样的瘤内血管流空影。增强后Ｔ1像明显强化，其程度较化学感受器瘤更为明显，并常可见脑膜尾征。•脑膜瘤典型的表现为“离心性”扩张和“匍匐状”生长，并有浸润颅神经和血管外膜的倾向。其对邻近骨质的破坏表现为广泛浸润板障而骨结构和骨密度得以保留，颈静脉孔边缘因皮质遭破坏而不规则。边缘往往有骨质增生或硬化的表现。颈静脉球瘤颈静脉孔骨质不规则的破坏、扩大，无骨质增生。MRI平扫颈静脉孔区肿块呈等Ｔ1，长Ｔ2像，轮廓不规则。瘤内可见点状，迂曲条状低信号影，肿瘤实质的高信号与低信号相间，称为“椒盐”征，这些条状的低信号影是流空的血管影，代表了肿瘤内扭曲扩张的血管，是该肿瘤的特征性表现。ＭＲＩ增强后Ｔ1像上明显不均匀强化，边界清晰。颈静脉球体瘤Fisch分型法(1978)分型范围A型肿瘤局限于中耳腔（鼓室球体瘤）B型肿瘤局限于鼓室乳突区域，无迷路下骨破坏C型肿瘤侵犯迷路下，扩展到岩尖部D1型肿瘤侵入颅内，直径小于2cmD2型肿瘤侵入颅内，直径大于2cm颈静脉球体瘤Glasscock-Jackson分型法(1981)分型范围I型肿瘤局限于鼓岬表面；肿瘤小，限于颈静脉球、中耳和乳突II型肿瘤完全充满中耳腔，侵犯至内听道下方，可有颅内侵犯III型扩展至乳突，侵犯岩尖部，可有颅内侵犯IV型扩展至乳突或穿透鼓膜至外耳道，或向前发展累及颈内动脉；肿瘤超出岩尖至斜坡或颞下窝，可有颅内侵犯Intracranialgrowthpatternofglom