颈静脉孔的解剖及临床应用

颈静脉孔的解剖及临床应用
颈静脉孔的解剖及临床应用

颈静脉孔的解剖及临床应用

颈静脉孔的解剖及临床应用

摘要:颈静脉孔由于位置深,解剖结构复杂,比较难理解,手术也难到达(5.6.7)。因其在大小和形态在不同颅骨的差异,在同一颅骨上两侧的不同,同一孔道颅内端与颅外端的不同,以及其形态不规则行程曲折、由两块颅骨构成,有诸多的颅神经和静脉管穿行其间,所以很难将其概念化。

1 颈静脉孔的位置形态

颈静脉孔是位于测颅底的枕、颞之间较大的不规则裂隙,外形和大小变异较大。由颞、枕骨共围成,位于颅底枕髁的外侧,左右各一,呈不规则的椭圆形。其内有后组脑神经和颈内静脉穿行,该孔为颅底最低点,有利于颅内静脉引流至颈内静脉。颞骨岩部下面有一深窝,为颈静脉窝,构成颈静脉孔的前内界及外界,窝内容纳颈静脉球。枕骨颈静脉突的前缘有一深而宽的切迹,为颈静脉切迹,构成颈静脉孔的后内界。在孔的外侧壁,有乳突小管存在,迷走神经耳支穿过此管。在其前缘有鼓室小管开口,舌咽神经鼓室支经此入鼓室。颈静脉孔内存在颞骨和枕骨向孔内突出的颈静脉内突,分别称为颞突和枕突,部分融合成骨桥。骨桥在影像学检查中具有一定意义。

2 颈静脉孔的结构毗邻

颈静脉孔外口的前方为颈动脉管外口,外侧为茎突、茎乳孔,再向后外侧为乳突。内侧为舌下神经管、枕髁和枕骨茎突。茎突是咽旁间隙的中心解剖标志,能保护其深面的颈内动脉、静脉和后组颅神经。颈静脉孔内口前内侧部的前外上方为内耳门,后内下方为舌下神经管,三者连线近乎一条直线。其后外侧为前庭导水管外口,后内侧可出现髁管。颈静脉孔前内侧部有岩下窦沟从颞骨岩尖向下沿岩枕裂延伸,其内有岩下窦至颈静脉孔注入颈内静脉。颈静脉孔后外侧部则有乙状窦沟从横窦外端沿颞骨乳突部延伸。颈静脉孔与周围结构的距离,与其本身的大小有关,主要与颈静脉窝的大小有关,颈静脉窝较大时,顶部与鼓室仅隔一层很薄的骨板。

3 颈静脉孔内结构

颈静脉孔内口前内侧部的前外上方为内耳门,后下方为舌下神经管,三者连线近乎成一直线。其后侧为前庭导水管外口,后内侧可出现髁管。颈静脉孔前内侧部有岩下窦从颞骨岩尖部向下沿岩枕裂延伸,其内的岩下窦与展神经一同通过Dorello管。岩下窦向外下方引流至颈内静脉。颈静脉孔后外侧部则有乙状窦沟从横窦沟外端沿颞骨乳突部延伸。乙状窦与乳突小房仅隔一层薄骨板,乳突手术时不要误伤。岩上窦位于颞骨岩部的上缘,将海绵窦的血液引入横窦延伸为乙状窦处。颈静脉孔外口的前方为颈动脉管外口,外侧为茎突、茎乳孔以及稍远处的乳突,内侧为舌下神经管、枕髁和枕骨大孔,后方枕骨茎突。茎突是咽旁间隙的中心解剖标志,能保护其神面的颈内动、静脉和后组颅神经。颈静脉神经部有舌咽神经和岩下窦通过。少数舌咽神经经神经部之前独立的骨管出颅。覆盖颈静脉孔的硬脑膜有2个持征性的穿孔。分别形成漏斗状的舌咽神经道相筛网状的迷走神经道,前者有舌咽神经穿过。后者有迷走神经和副神经穿过;由于吞咽、迷走神经起点邻近.且常有蛛网膜粘连,因而在脑干附近或蛛网膜下腔很难将二者确切分开,唯有在舌咽神经道与迷走神经道间的硬膜隔处方可分辨。乙状窦进入颈静脉孔的静脉部后延续为颈静脉球。岩下窦接纳斜坡区的血液,形成单一或多个静脉道,在舌咽—迷走神经间,或舌咽神经前,或迷走神经后.或迷走—副神经间穿过。汇入颈静脉球内侧壁。

4 颈静脉孔与临床应用

颈静脉孔发生病变时,较大颈静脉孔的症状出现相对较晚,然而较大的颈静脉孔血流量大,处理横窦时并发症相对较多。由于颈静脉孔大小的不同,可推断两侧颈静脉球的大小及血流量的多少。因此,术前骨窗CT显示颈静脉孔大小有助于推断两侧颈静脉血流量的多少。(1)

颈静脉孔临床综合征:为颈静脉孔发生病变时可出现的第IX、X、XI脑神经麻痹症候群。IX、X麻痹可致同侧软腭、咽部感觉障碍,舌后1/3部味觉缺失;声带和软腭麻痹致声音嘶哑,病侧咽反射消失。XI麻痹出现病侧胸锁乳突肌和斜方肌麻痹和萎缩,临床表现为不能

向对侧转颈,不能耸肩。偶可出现耳鸣、耳聋和面神经麻痹等症状。villaret`s、Horner`s 、ver net`s 综合征与IX---XII神经有关;sicard 、Jackson`s 、sieben mann`s 和vernet`s为颈静脉孔周围颅内区域受影响导致;而schmiedt`s是由于第X和XI颅外区域受影响导致。

参考文献

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学技术出版社,2010:198-205

[2]德.Johannes Lang著,孙为群、滕良珠译,颅底与相关结构临床解剖图谱[M].山东科学技术出版社,2002:267-274

[3]刘庆良、王忠诚、于春江,颈静脉孔区显微解剖(J).中华

神经外科杂志,2004,20:10-13

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颈静脉孔区解剖

CHAPTER 12 J UGULAR F ORAMEN The jugular foramen is located between the temporal and the occip-ital bones. It can be regarded as a hiatus between the temporal and the occipital bones (1). The right foramen is usually larger than the left. The foramen is configured around the sigmoid and inferior petrosal sinuses. The jugular foramen is divided into three compartments: two venous compartments and a neural or intrajugular compartment. The venous compartments consist of a larger posterolateral venous channel, the sigmoid part, which receives the ?ow of the sigmoid sinus, and a smaller anteromedial venous channel, the petrosal part, which receives the drainage of the inferior petrosal sinus. The petrosal part forms a characteristic venous con?uens by also receiving tributaries from the hypoglossal canal, petroclival ?ssure, and vertebral venous plexus. The petrosal part empties into the sigmoid part through an opening between the glossopharyngeal and the vagus nerves in the medial wall of the jugular bulb. The intrajugular or neural part, through which the glossopharyngeal, vagus, and accessory nerves course, is located between the sigmoid and petrosal parts. The junction of the sigmoid and petrosal parts of the foramen, when viewed from above, is the site of bony prominences on the opposing surfaces of the temporal and occipital bones, called the intrajugular processes, which are joined by a ?brous, or, less commonly, an osseous bridge, the intrajugular sep-tum, separating the sigmoid and petrosal part of the foramen. The glossopharyngeal, vagus, and accessory nerves penetrate the dura on the medial margin of the intrajugular process of the temporal bone to reach the medial wall of the jugular bulb and internal jugular vein. The jugular foramen is dif?cult to access surgically. The dif?culties in exposing this foramen are created by its deep location and the sur-rounding structures, such as the carotid artery anteriorly, the facial nerve laterally, the hypoglossal nerve medially, and the vertebral artery inferiorly, all of which block access to the foramen and require careful management. The structures that traverse the jugular foramen are the sigmoid sinus and jugular bulb, the inferior petrosal sinus, meningeal branches of the ascending pharyngeal and occipital arteries, the glossopharyn-geal, vagus, and accessory nerves with their ganglia, the tympanic branch of the glossopharyngeal nerve (Jacobson’s nerve), the auricular branch of the vagus nerve (Arnold’s nerve), and the cochlear aqueduct. Tumors involving the jugular foramen can extend as follows: 1) along the eustachian tube into the nasopharynx and through the foramina at the base of the cranium, 2) along the carotid artery to the middle fossa, 3) through the intracranial ori?ce of the jugular foramen or along the hypoglossal canal to the posterior fossa, 4) through the tegmen tym-pani to the ?oor of the middle fossa, 5) through the round window and the internal acoustic meatus to the cerebellopontine angle, and 6) through the extracranial ori?ce of the jugular foramen to the upper cer-vical region. Surgical Approaches The most common operative approaches used to access various aspects of the foramen and adjacent areas are the postauricular transtemporal, retrosigmoid, and far lateral approaches. Postauricular Transtemporal Approach The postauricular transtemporal approach, the most common approach selected for a lesion in the jugular foramen, accesses the region from laterally, through the mastoid, and from below, through the neck. A C-shaped postauricular skin incision provides the exposure for a mastoidectomy and the neck dissection. The external auditory canal is either preserved or transected, depending on the anterior extent of the pathological abnormality. The neck dissection is com-pleted initially to gain control of the major vessels and the branches supplying the tumor. The internal carotid artery, branches of the exter-nal carotid artery, internal jugular vein, and lower cranial nerves are exposed in the carotid sheath. A mastoidectomy with extensive drilling of the infralabyrinthine region accesses the jugular bulb. A limited mas-toidectomy con?ned to the area behind the stylomastoid foramen and mastoid segment of the facial nerve, combined with removal of the adjacent part of the jugular process of the temporal bone, will provide access to the posterior and posterolateral aspect of the jugular foramen. Three obstacles to exposure of the full lateral half of the jugular fora-men, the facial nerve, styloid process, and rectus capitis lateralis mus-cle are dealt with by transposing the facial nerve, removing the styloid process, and dividing the rectus capitis lateralis muscle. Anterior exten-sions of the pathological abnormality are reached by sacri?cing the external and the middle ear structures. Sensorineural hearing can be preserved by maintaining the footplate of the stapes in the oval win-dow to avoid opening the labyrinth. Intracranial extensions of the lesion are reached by the retrosigmoid or presigmoid approaches after adding a suboccipital craniectomy. Some lesions can be removed by a transtemporal infralabyrinthine approach directed through the tem-poral bone below the labyrinth without a neck dissection, if the extracranial extension of the lesion is not prominent. The exposure can be extended by opening the otic capsule (translabyrinthine approach). Retrosigmoid Approach A lesion located predominantly intradurally above the jugular fora-men can be resected by the retrosigmoid approach. A lateral suboccip-ital craniectomy exposes the dura behind the sigmoid sinus. The dura is opened, and the cerebellum is gently elevated away from the poste-rior surface of the temporal bone to expose the cisterns in the cerebel-lopontine angle and the intracranial aspect of the cranial nerves enter-ing the jugular foramen, hypoglossal canal, and internal acoustic meatus. Lesions can be followed into only the upper part of the fora-men by this approach. Far Lateral Approach An extended modi?cation of the retrosigmoid approach, the far lat-eral approach, may be selected if the tumor extends down to the fora-men magnum in front of or lateral to the lower brainstem. In this approach, the jugular foramen is opened from behind by completing a paracondylar modi?cation of the far lateral approach. In this modi?ca-tion, the rectus capitis lateralis is detached from the occipital bone at the posterior margin of the foramen and the posterior margin is removed. The dura is opened and the cerebellum elevated to expose the intracranial extension of the pathological abnormality at the lower clivus and at the foramen magnum. In another variant of the approach, depending on the location and extent of the pathological abnormality, the jugular tubercle is removed extradurally to minimize the retraction of the brainstem needed to reach the area anterior to the medulla and pontomedullary junction. Most jugular foramen tumors cannot be reached by this route because they extend forward beyond the limits of this approach to the posterior part of the foramen. REFERENCES 1.Rhoton AL Jr: Jugular foramen. Neurosurgery47[Suppl 3]:S267–S285, 2000.

下肢静脉的解剖

下肢静脉的解剖 一、下肢动脉 (一)股动脉股动脉是下肢动脉的主干,由髂外动脉延伸而来,经腹股沟中点的深面,通过股三角进入内收肌管。在腹肌沟韧带稍下方,股动脉位置表浅,活体上可以触摸到其搏动,当下肢出血时,可以在此处将股动脉压迫进行止血。股动脉在肢体分出股浅动脉和股深动脉。股浅动脉是下肢最主要的供血动脉。股深动脉是股动脉最大的分支,股深动脉又分出旋股外侧动脉和旋股内侧动脉。当股浅动脉出现闭塞和外伤时,肢体的供血主要靠股深动脉及其侧支循环。股动脉是临床上最常应用和解剖的动脉,这其中有血管造影、各部位动脉腔内成型、血管支架、带膜支架的置入、下肢血管手术等。临床上还用于股动脉穿刺和急救时压迫止血。 (二)腘动脉是股动脉在腘窝的直接延续,位置较深。当股骨髁上骨折时可能伤及腘动脉。腘动脉是大腿和小腿血管连接的枢纽,在此部位侧支循环很少,心脏附壁血栓脱落后常阻塞该动脉,造成急性动脉栓塞。由于腘动脉是大腿和小腿动脉血管连接的枢纽,故腘动脉受伤后必须修复和重建。 (三)胫前动脉、胫后动脉腘动脉通过腘窝后在小腿分出 3 根主要血管:胫前、胫后和腓动脉。在腘窝下角,腘动脉通常分成两终末支,胫前动脉和胫后动脉。胫后动脉主干经内踝后方进入足底,起始处发出腓动脉。在肢体急、慢性缺血情况下,三条动脉通常是下肢动脉拱桥和静脉动脉脉化的吻合部位,而当 3 条精选资料,欢迎下载

动脉中有一根通畅,则意味着缺血肢体可以生存、恢复、缓解。 (四)足背动脉胫前动脉移行为足背动脉。行于足背内侧拇长伸肌 腱和趾长伸肌腱之间,经第1、2 跖骨间隙至足底。在踝关节前方, 内外踝连线中点,拇长伸肌腱的外侧可触及搏动。足部出血进可以压 迫此处的足背动脉进行止血。在临床上,足背动脉、胫后动脉搏动 的强弱常用来检查下肢动脉重建术后肢端血供的情况。 二、下肢静脉 下肢静脉内有丰富的向心单向开放的瓣膜,阻止静脉血逆流,保证下肢静脉血由下向上,由浅入深地单向回流。下肢静脉分为浅, 深两组,浅静脉和深静脉有许多交通支相连,最终汇入深静脉。 (一)浅静脉主要有大隐静脉和小隐静脉。大隐静脉在足内侧起自 足背静脉弓内侧端,经内踝前方沿小腿内侧和大腿前内侧面上行, 至耻骨结节外下方入深面,注入股静脉。大隐静脉在内踝前方位置表 浅,易发生静脉曲张。临床上也常用来作静脉穿刺或切开输液。 它在血管外科常用来作为血管拱桥或血管补片的材料。小隐静脉在足 的外侧缘起自足背静脉弓外侧端,在外踝后方上行至腘窝,穿深筋 膜注入腘静脉。 二)深静脉足和小腿的深静脉与同名动脉伴行,均为两条。胫前、胫后静脉汇合成腘静脉。在膝下每条动脉有两条静脉伴行,上行到腘窝合成 一条腘静脉。穿收肌腱裂孔移行为股静脉,它伴随股 动静上行,初在其外侧,后转至内侧,达腹股沟韧带深面移行为髂外 静脉。股静脉收集下肢所有浅、深部的静脉血,最后流向心脏。如以

颈静脉孔的解剖及临床应用

颈静脉孔的解剖及临床应用 颈静脉孔的解剖及临床应用 摘要:颈静脉孔由于位置深,解剖结构复杂,比较难理解,手术也难到达(5.6.7)。因其在大小和形态在不同颅骨的差异,在同一颅骨上两侧的不同,同一孔道颅内端与颅外端的不同,以及其形态不规则行程曲折、由两块颅骨构成,有诸多的颅神经和静脉管穿行其间,所以很难将其概念化。 1 颈静脉孔的位置形态 颈静脉孔是位于测颅底的枕、颞之间较大的不规则裂隙,外形和大小变异较大。由颞、枕骨共围成,位于颅底枕髁的外侧,左右各一,呈不规则的椭圆形。其内有后组脑神经和颈内静脉穿行,该孔为颅底最低点,有利于颅内静脉引流至颈内静脉。颞骨岩部下面有一深窝,为颈静脉窝,构成颈静脉孔的前内界及外界,窝内容纳颈静脉球。枕骨颈静脉突的前缘有一深而宽的切迹,为颈静脉切迹,构成颈静脉孔的后内界。在孔的外侧壁,有乳突小管存在,迷走神经耳支穿过此管。在其前缘有鼓室小管开口,舌咽神经鼓室支经此入鼓室。颈静脉孔内存在颞骨和枕骨向孔内突出的颈静脉内突,分别称为颞突和枕突,部分融合成骨桥。骨桥在影像学检查中具有一定意义。 2 颈静脉孔的结构毗邻 颈静脉孔外口的前方为颈动脉管外口,外侧为茎突、茎乳孔,再向后外侧为乳突。内侧为舌下神经管、枕髁和枕骨茎突。茎突是咽旁间隙的中心解剖标志,能保护其深面的颈内动脉、静脉和后组颅神经。颈静脉孔内口前内侧部的前外上方为内耳门,后内下方为舌下神经管,三者连线近乎一条直线。其后外侧为前庭导水管外口,后内侧可出现髁管。颈静脉孔前内侧部有岩下窦沟从颞骨岩尖向下沿岩枕裂延伸,其内有岩下窦至颈静脉孔注入颈内静脉。颈静脉孔后外侧部则有乙状窦沟从横窦外端沿颞骨乳突部延伸。颈静脉孔与周围结构的距离,与其本身的大小有关,主要与颈静脉窝的大小有关,颈静脉窝较大时,顶部与鼓室仅隔一层很薄的骨板。

颈静脉孔的应用解剖学

#应用解剖# 颈静脉孔的应用解剖学 肖 明, 丁 炯, 韩群颖, 王鹤鸣, 左国平 (南京医科大学解剖学教研室,江苏南京210029) =摘要>目的:为与颈静脉孔相关的影像诊断和临床治疗提供解剖学资料。方法:从颅底内、外面,对80具成年颅骨的颈静脉孔进行观测;并对20具成人尸头进行解剖,观察该区域神经血管解剖关系。结果:162.3%右侧颈静脉孔较左侧大,15.9%左侧较大,21.8%两侧大小一致;o14.38%的颈静脉孔有骨桥,85.62%无骨桥;?颈静脉孔内、外侧缘距正中矢状面两侧的平均距离颅外均较颅内大:颅外分别为26.11mm 和33.41mm,颅内分别为22.29mm 和27.52mm 。?ù脑神经多沿颈静脉孔前上缘,ú、?脑神经沿内侧缘出颅,两者被纤维索(占87.5%)或骨桥(占12.5%)隔开。?ù脑神经多经颈静脉孔外口前上缘向前下越过颈内动脉表面;ù脑神经经颈内静脉深面(占57.5%)或其浅面(42.5%)行向后下。结论:右侧颈静脉孔通常较左侧大,左右不对称;影像学观测该区域血管、神经应选择恰当的层面。 =关键词>颈静脉孔; 颈内静脉; 脑神经; 应用解剖学 =中图分类号>R323.1 =文献标识码>A =文章编号>1001-165X(2001)02-0159-03Applied anatomy of jugular foramen XIAO Ming,DING J ong ,HAN Qun -ying,et al.De p a rtment o f A natom y ,Nan j ing Medical University ,Nan j ing 210029,China =Abstract >Objective:To provide anatomic data for imaging diagnosis and microsurgical treatment of jugular fora -men (JF)lesions.Methods:The JF was observed and measured from internal and external aspects in 80adult skulls.The anatomic relationships between the nerves and vessles in this region were observed i n detail by dissecting 20adult cephalic specimens.Results:1In 62.3%of all these cases the right JF was larger than the left.In 15.9%the left was larger and in 21.8%they were equal in size.oBone bridges could be seen in 14.38%and could not in 85.62%.?Measured from extracranial aspect,the average distance from midsagi ttal plane to the medial and lateral border of the JF (medial 26.11mm,lateral 33.41mm),was larger than those measured from intracramial aspect (medial 22.29mm,lat -eral 27.52mm).?ùcranial nerve made its ex i t through the anterior superior border of the JF in most cases,meanwhile úand ?cranial nerve through the medial border,they were distinctly separated from each other by a band of fibrous tissue (account for 87.5%)or a bone bridge (12.5%).?Jus t outside the J F,ùcranial nerve appeared at the anter-i or border and made a loop downward and forward superficial to the internal carotid artery.ùcranial nerve run down ward and back ward deep (account for 57.5%),or superficially (42.5%)to the internal jugular vei n.Conclusions:T he right J F is usually larger than the left,and not symmetry on both sides.The key to imaging diagnosi s of nerves and ves -sels in the JF region is to select the sectional plane correctly. =Key w ords >Jugular foramen; Internal jugular vein; Cranial nerve; Applied anatomy 颈静脉孔为枕骨与颞骨岩部之间的一骨性孔道,位于岩枕缝的后端,被颈内静脉结节分为二部或三部[1] 。前部有岩下窦注入,与ù~?脑神经通过;后部较大,乙状窦经此延续为颈内静脉。上述诸结构在颈静脉孔内的位置与相互毗邻关系,国内外有关文献描述甚不统一[2,3] 。本实验目的是观察颈静脉孔的形态、内容物的相互关系,具体测量其孔径大小两侧对称性,为影像学观测提供相应的形态学资料。1 材料和方法 材料为教研室标本室提供的80只成年男女颅骨(不分性别),经耳颞线将颅骨锯开。对颈静脉孔大体形态进行观察,并着重观察有无骨桥(完整与否)及其类型与出现率;根据Doclo 制定的原则将骨桥进行分类:位于舌下神经管前上方者为?型,位于舌下神经管后方的为ò型。分别从颅内测量颈静脉孔的最大、最小横径,矢状径(图1);从颅外测量横径与矢状径,并从颅内、外面对颈静脉孔内、外侧缘距正中矢状面距离进行测 =收稿日期>2000-03-11 =作者简介>肖 明(1972-),男,江苏盐城人,硕士,讲师,主要从 事临床解剖学研究,Tel:(025)6662879,E -mail:renjie@https://www.360docs.net/doc/0719006884.html, 。 量。测量仪器为颅骨测径器。另20例成年尸头标本(男12例, 女8例),于颞骨乳突中部与耳颞线平行锯断,移去颅骨的上端,细心将ù、ú、?脑神经从脑干背面剪断,剔除脑组织,保留颈静脉孔周围的硬脑膜,观察上述神经在孔内口的位置及与岩下窦相互毗邻关系;去除颅底肌肉等软组织,暴露颈内静脉孔外口,观察颈内静脉与ù、ú、?脑神经的解剖关系。 AB.横径(transverse diameter) CD.最大矢状径(maximum sagittal diameter)E F.最小矢状径(minimum sagi ttal diameter)图1 颈静脉孔的各径线颅内测量示意图 Fig.1 Intracranial measuremen ts of the schematic drawing of diameters of the jugular foramen # 159#中国临床解剖学杂志2001年第19卷第2期

心脏冠状动脉和心静脉解剖图(干货)

心脏冠状动脉和心静脉解剖图 人体各组织器官要维持其正常的生命活动,需要心脏不停地搏动以保证血运.而心脏作为一个泵血的肌性动力器官,本身也需要足够的营养和能源,供给心脏营养的血管系统,就是冠状动脉和静脉,也称冠脉循环。 冠状动脉是供给心脏血液的动脉,起于主动脉根部,分左右两支,行于心脏表面.正常情况下,它对血液的阻力很小,小于总体冠状动脉阻力的5%,从心外膜动脉进入心壁的血管,一类呈丛状分散支配心室壁的外、中层心肌;一类是垂直进入室壁直达心内膜下(即穿支),直径几乎不减,并在心内膜下与其它穿支构成弓状网络,然后再分出微动脉和毛细血管。丛支和穿支在心肌纤维间

形成丰富的毛细血管网,供给心肌血液.......感谢聆听由于冠状动脉在心肌内行走,显然会受制于心肌收缩挤压的影响。也就是说,心脏收缩时,血液不易通过,只有当其舒张时,心脏方能得到足够的血流,这就是冠状动脉供血的特点。人心肌的毛细血管密度很高,约为2500根/mm2,相当于每个心肌细胞伴随一根毛细血管,有利于心肌细胞摄取氧和进行物质交换。......感谢聆听 同时,冠状动脉之间,尚有丰富的吻合支或侧支。冠状动脉虽小,但血流量很大.占心排血量的5%,这就保证了心脏有足够的营养,维持它有力地昼夜不停地跳动。冠状静脉伴随冠状动脉收集代谢后的静脉血,归流于冠状静脉窦,回到右心房。如果冠状动脉突然阻塞,不能很快建立侧支循环,常常导致心肌梗塞.但若冠状动脉阻塞是缓慢形成的,则侧支可逐渐扩张,并可建立新的侧支循环,起代偿的作用。......感谢聆听

目前,冠脉的介入治疗和手术治疗都基于其造影,冠脉造影还被广泛应用于对冠心病患者预后的评价和估计,基于冠脉造影的冠脉血流储备测定

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