KISEP KOR J CEREBROVASCULAR DISEASE September 2000 Vo. 2, No 2, page 101-6 두개강외및해면정맥동부내경동맥의미세혈관해부 김재민 Microvascular Anatomy of Extreacranial and Cavernous Internal Carotid ArteryICA Jae Min Kim, MD, PhD Department of Neurosurgery, Hanyang University Kuri Hospital, Kuri, Korea ABSTRACT Although lacking of unanimously accepted nomenclature and numbering system of the internal carotid artery ICA segments, recently adopted system may be applicable in terms of its simplicity and practical purposes. According to this seven-tier system, we briefly summarized the normal microvascualr anatomy of the ICA from the extracranial cervical C1 segment to the clinoid C5 segment of the ICA and surrounding structures with relevant schematic drawings. Also we presented a spectrum of normal variants and congenital anomalies with respect to the normal anatomy. Kor J Cerebrovascular Disease 2:101-6, 2000 KEY WORDSInternal carotid atery Cervical segment Clinoid segment Anatomy. 서 론 정상해부학및선천성기형 1. C1:Cervical ICA 101
Fig. 1. Lateral anatomic diagram depicting the 7 segments of the internal carotid artery. C1cervical segment the bulb is shown as dotted, and the ascending segment is indicated by the horizontal lines, C2petrous segment, C3lacerum segment, C4cavernous segment, C5clinoid segment, C6 ophthalmic segment, C7communicating terminal segment. This new classification presented by Bouthillier et al., 1996. 1) Anomalous origin of ICA 2) Agenesis, congenital absence of the ICA Fig. 2. Anatomic diagram from anteroposterior to a left anterior oblique projection depicts the definite left common carotid artery as well as the external and internal carotid arteries and the embryonic origin of these vessels is also shown. APAascending pharyngeal artery, CTAcaroticotympanic artery, IMAinternal maxillary artery, MMAmiddle meningeal artery, OAophthalmic artery, STAsuperficial temporal artery. Small single arrowstapes, Arrow headforamen spinosum, Double arrowsoptic canal, Open arrowscarotid canal. 3) Anomalous branches 4) Carotid-basilar anastomoses 102 Kor J Cerebrovascular Disease 2:101-6, 2000
Fig. 3. Anatomic diagram depicting the embryologic carotidbasilar and carotid-vertebral anastomoses. The posterior communicating artery is the only vessel that normally persists the other four, shown in black, usually regress completely. 1posterior communicating artery, 2trigeminal artery, 3 otic artery, 4hypoglossal artery, 5 proatlantal intersegmental artery. 5) Fibromuscular dysplasia(fmd) Fig. 4. Schematic drawing depicts the petrous C2 ICA as well as its branches and adjacent structures. C2 ICA has an ascending segment, a posterolateral genu, and a longer horizontal segment. The C3 lacerum ICA segment is a short segment that extends from the endocranial opening of the carotid canal to the petrolingual ligament PL. OCoptic canal, SOFsuperior orbital fissure, SPGsphenopalatine ganglion, PTPFpterygopalatine fossa, GSPNgreater superficial petrosal nerve, VAvidian artery, CTAcaroticotympanic artery, ETeustachian tube, FLforamen lacerum, CT chorda tympani, IMAinternal maxillary artery. Cranial nerves are indicated by the Roman numerals. 2. C2:Petrous ICA Kor J Cerebrovascular Disease 2:101-6, 2000 103
1) Vidian artery (artery of pterygoid canal) 2) Caroticotympanic artery 3) Aberrant petrous ICA 4) Carotid-basilar anastomoses 3. C3:Lacerum ICA 4. C4:Cavernous ICA A B Fig. 5. ALateral anatomic diagram showing the distal ICA and its relationship to adjacent structures. The lateral dural wall of the carotid sinus has been removed. The C4 cavernous ICA begins as the ICA passes under the petrolingual ligament PL and enters the cavernous sinus. The C5 clinoid segment lies between the proximal dural ring PDR and the distal dural ring DDR. MHTmeningohypophyseal trunk, ILTinferolateral trunk, GGGasserian ganglion, FRforamen rotundum. BAnteroposterior anatomic drawing showing the ICA and cavernous sinus CS in coronal section. The C4 ICA segment is surrounded by the endothelial-lined venous sinusoids that comprise the cavernous sinus. MCMeckels cave, FOforamen ovale, AC anterior clinoid process, OCoptic chiasm, SSsphenoid sinus. 104 Kor J Cerebrovascular Disease 2:101-6, 2000
김 재 민 erian ganglion GG)이 C3와 posterior C4 segment를 덮 여 있으며 내경동맥은 basisphenoid bone의 얇은 구인 경 고 있으며 Meckel s cave 저부를 형성하는 경막층에 의해 동맥구를 따라 앞으로 주행한다. C4의 내측으로는 접형동이 분리되어 있다. 더 앞쪽으로는 동안신경, 활차신경, 외선신 있으며 이와의 경계는 60 70%에서 1 mm 이하 두께의 뼈 경이 C4의 측벽을 주행하며 이중, 외선신경만이 해면정맥동 로 분리되어 있으며 4% 정도에서는 경막외층(골막)으로만 실질(cavernous sinus proper) 안에 위치한다. 덮여 있다. C4의 위쪽으로는 소뇌천막 변연이 지나가며 앞 C4는 실질적으로 해면정맥동 실질 안의 가장 내측 구조 쪽에서 해면정맥동과 소뇌천막의 dural reflection이 합쳐져 로서 내피세포로 덮인 sinusoids와 얇은 벽의 세정맥으로 덮 proximal, distal dural ring을 형성하여 전상상돌기를 감싼 후 C4-C5 이행부를 부분적으로 덮는다. 터어키안 와와 뇌 하수체가 C4의 상내측에 위치하고 얇은 골성 층판과 해면 정맥동의 얇은 경막벽으로 구분된다. 경동맥구, 삼차신경의 제1, 2분지가 아래를 지나가고, anterior genu의 앞쪽으로 optic strut와 전상상돌기가 위치한다(Fig. 5).1)3)4)6) C4의 분지로는 1) posterior trunk, 2) inferolateral trunk, 및 3) medial trunk가 있다. 1) Posterior trunk (meningohypophyseal trunk MHT) 대부분의 경우 관찰되며 C4의 posterior genu 위쪽으로 기시한다. 크게 3개의 분지를 내며 각각 뇌하수체(inferior hypophyseal artery), 소뇌천막(marginal tentorial artery of Bernasconi & Cassinari), 사대(clival branch, or dorsal meningeal artery)에 분포한다. Fig. 6. Branches of cavernous ICA. 1 ICA, 2 caroticotympanic branch, 3 meningohypophyseal trunk (3a inferior hypophyseal artery, 3b dorsal meningeal branch, 3c tentorial branch), 4 inferior cavernous sinus artery (4a branches to Ⅲ, Ⅳ, Ⅵ cranial nerves, 4b branches to Gasserian ganglion, 4c anastomoses to middle meningeal artery), 5 capsular artery (sellar floor), 6 ophthalmic artery. A 2) Lateral trunk (inferolateral trunk ILT) 66 84%에서 관찰되며 C4 horizontal segment의 측방 에서 기시하며 해면정맥동 내에서 외선신경을 가로질러 주 행한다. 2 3개의 중요한 분지를 내며 이들은 각각 동안신 경, 활차신경, 외선신경과 삼차신경절, 해면정맥동의 경막에 B Fig. 7. A Schematic drawing of microanatomic features of the clinoid (C5) segment of the ICA, showing a lateral view of the left cavernous sinus after an anterior clinoidectomy. The inner dural layer of the roof of the cavernous sinus reflects off the oculomotor nerve to form the proximal dural ring and then covers along the C5 segment of the ICA, where it fuses with the distal dural ring. B Schematic drawing showing the small space that exists between the inner dural layer and the clinoid ICA. This space admits the passage of veins (through the incompetent proximal dural ring) that are in direct communication with the anterior cavernous sinus. Kor J Cerebrovascular Disease 2:101-6, 2000 105
3) Medial branches 4) Persistent trigeminal artery (PTA) 5) Intercavernous anastomoses 5. C5:Clinoid ICA 중심단어 : REFERENCES 1) Bouthillier A, van Loveren HR, Keller JT. Segments of the Internal Carotid Artery: A New Classification. Neurosurgery 38:425-33, 1996 2) Gibo H, Lenkey C, Rhoton Jr A. Microsurgical anatomy of the supraclinoid portion of the internal carotid artery. J Neurosurg 55: 560-74, 1981 3) Huber P. Cerebral Angiography, ed 2. Stuttgart: Georg Thieme Verlag, 1986, pp 36-68 4) Kim JM, Romano A, Sanan A, et al. Microsurgical anatomic features and nomenclature of the paraclinoid region. Neurosurgery 46:670-82, 2000 5) Kobayashi S, Kyoshima K, Gibo H, et al. Carotid cave aneurysms of the internal carotid artery. J Neurosurg 70:216-21, 1989 6) Osborn AG. Diagnostic Cerebral Angiography, ed 2. Philadelphia: Lippincott Williams & Wilkins, 1999, pp 31-104 7) Silver JM, Wilkins RH. Persistent embryonic intracranial and extracranial vessels, in Wilkins RH, Rengachary SS (eds): Neurosurgery, ed 2. New York: McGraw-Hill, 1996, Vol Ⅱ, pp 1987-95 8) Tauber M, van Loveren HR, Jallo G, et al. The enigmatic foramen lacerum. Neurosurgery 44:386-93, 1999 106 Kor J Cerebrovascular Disease 2:101-6, 2000