REVIEW J Neurocrit Care 2016;9(2):71-77 eissn 2508-1349 두개뇌압항진과뇌탈출증의임상증상 홍정호계명대학교동산병원신경과 Clinical Manifestations of Intracranial Hypertension and Herniation Syndrome Jeong-Ho Hong, MD, PhD Department of Neurology, Keimyung University Dongsan Medical Center, Daegu, Korea Neurocritically ill patients commonly develop secondary brain injury such as brain herniation and intracranial hypertension because of space occupying lesion in the brain. Currently, the aim of neurocritical care is early detection and minimizing secondary brain injury. In order to meet these treatment goals, an awareness of associated symptoms and signs of patients in the neurological intensive care unit is needed, even in those with decreased consciousness due to severe brain injury. In this review, we aimed to describe clinical manifestations and imaging findings of intracranial hypertension and brain herniation. J Neurocrit Care 2016;9(2):71-77 Key words: Critical illness; Intensive care unit; Intracranial hypertension; Elevated intracranial pressure; Cerebellar herniation; Tonsillar herniation Received November 1, 2016 Revised November 15, 2016 Accepted December 7, 2016 Corresponding Author: Jeong-Ho Hong MD, PhD Department of Neurology, Keimyung University Dong San Medical Center, 56 Dalseong-ro, Jung-gu, Daegu 41931, Korea Tel: +82-53-250-7317 Fax: +82-53-250-7840 Email: neurohong79@gmail.com Copyright 2016 The Korean Neurocritical Care Society 서론 신경계중환자실에서는허혈성뇌졸중, 출혈성뇌졸중, 뇌종양같이단일뇌병변에의한두개내압항진을자주경험하게된다. 이경우에 Monro-Kellie doctrine에근거한뇌압상승뿐아니라덩이효과자체에의해뇌탈출 (brain herniation) 을유발될수있고심할경우사망에이르기도한다. 일부에서는국소적인뇌병변이아닌뇌전반에걸친염증성질환이나저산소뇌손상 ( 예, 심정지후저산소뇌병증 ) 에의해서도뇌탈출이발생할수있다. 신경집중치료의주된목적중하나는일차뇌손상이후에발생할수있는이차뇌손상을예측하여미연에방지하고, 이차뇌손상이발생한다면조기발견과신속한치료를하는것이다. 하 지만, 신경계중환자실에서치료받는환자는대개의식이비정상적인경우가많다. 또한, 덩이효과의종류에따라나타날수있는증상이다르기때문에신경계중환자실을담당하는전문의나전공의들은각각의특징적인증상에대해서알아야만한다. 증상이발생하여덩이효과나뇌탈출이의심되는경우활력징후가불안정하지않다면신속히컴퓨터단층촬영이나자기공명영상등뇌영상을시행하고, 조기에신속한치료를하여야한다. 본종설에서는신경계중환자실에서접할수있는뇌압상승때나타날수있는전반적인증상뿐만아니라뇌탈출의종류및특징적인임상증상에대해살펴보고자한다. cc This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. www.e-jnc.org 71
본론 1. 두개내압상승의증상일반적으로뇌출혈이나뇌경색의범위가매우크거나뇌종양등으로인한부종이심해지면뇌의덩이효과로인해두개내압이상승할수있으며이로인한증상및징후로두통, 구토, 안구마비, 의식변화, 유두부종등이발생할수있다. 장시간에걸친유두부종은시신경위축을일으켜시력장애를유발하고결국실명까지초래할수있다. 두통은특징적으로자고일어난뒤아침에심해지며이는수면중호흡저하로인해산소공급이저하되고자는자세역시누운상태로뇌부종이악화될수있기때문이다. 이러한두통은기침, 재채기, 굽힘자세에의해서더악화된다. 이외에도고전적인뇌압상승징후로쿠싱의 3징 (Cushing s triad) 인수축기혈압상승, 맥박수감소, 불규칙적인호흡이나타날수있다. 1,2 뇌압이상승하면교감신경과부교감신경모두활성화되는데초기에는부교감신경보다는교감신경 이더활성화되어알파-1 아르레날린수용체를활성화하고이로인해체내의혈관을수축시킴으로혈압을올리게된다. 3 뿐만아니라초기교감신경의자극은심박동수와심박출량도함께증가시키게되며, 이러한반응은뇌압상승으로인한부적절한뇌혈류와세동맥의압박으로뇌허혈반응이진행하는것을보호해주는역할을하기도한다. 한편, 증가된혈압때문에대동맥궁 (aortic arch) 의압수용기 (baroreceptors) 는미주신경을통해부교감신경을자극하게되고이로인해중기반응으로서맥이발생하게된다. 4 이때활성화된미주신경는위벽세포 (gastric parietal cell) 의과활성화를유발하여과도한위산을분비하게하여위염 ( 쿠싱궤양 ) 이발생할수있다. 5 뇌압상승으로 15 mmhg 이하의심한뇌관류압장애가생길경우혈압상승과서맥은약 93% 에서관찰된다. 6 이후말기가되면증가된뇌압, 다양한내인성자극들은뇌간에영향을주고이로인해호흡주기조절의변화로불규칙적인호흡이발생하게된다. 1 Figure 1. Types of brain herniation. 72
Jeong-Ho Hong Intracranial hypertension and herniation syndrome 2. 뇌탈출의증상이렇듯두개내압상승에의한증상은뇌전반에걸쳐영향을주고이로인한비특이적인증상을유발시킨다. 쿠싱의 3 징역시두개강내압의급성기로발생하여지속적으로유지될때관찰된다. 반면, 뇌탈출은뇌병변부위가커지면서덩 이효과로인해국소뇌조직을압박하여손상부위에따른특징적인증상을나타내게된다. 두개내공간은단단한구조의대뇌낫 (falx cerebri) 과소뇌천막 (tentorium cerebelli) 으로이루어진구획이존재하며, 큰구멍 (foramen magnum) 을경계로척수강내공간과분리되어있다. 이때문에국소적인덩 Table 1. Clinical symptoms and image findings according to types of brain herniation Syndrome Clinical manifestations Image findings Subfalcine (cingulate) Uncal (transtentorial) Central (tentorial) Tonsillar (downward cerebellar) Upward Transcalvarial (external) - Most common herniation syndrome - Contralateral extremity paresis (leg/shoulder > arm/ hand/face) - Abulia, akinetic mutism and urinary incontinence - Second most common herniation syndrome - Ipsilateral pupillary dilatation (Hutchinson pupil) and down and out deviation of eyeball and ptosis due to injury to the outer fibers of the occulomotor nerve - Contralateral homonymous hemianopsia - Depressed level of consciousness - Ipsilateral (false localizing sign) or contralateral (compression of cerebral peduncle) hemiparesis, decerebrate posturing - Central neurogenic hyperventilation - Impaired consciousness and eye movements - Bilateral decorticate or decerebrate posturing - Loss of consciousness - Episodic tonic extension and arching of the back and neck, extension and internal rotation of limbs - Loss of consciousness - Cardiac arrhythmias, Sudden changes in BP and heart rate - Small pupils - Ataxic breathing, respiratory arrest - Disturbance of conjugate gaze, nystagmus - Quadriparesis - Coma with reactive, miotic pupils - Asymmetrical or absent caloric responses - Decerebrate posture - May occur during craniectomy surgery in which a flap of skull is removed - Depends on the location - Displacement of the cingulate gyrus under the falx cerebri and across the midline, with anterior displacement much more common than posterior - Compression of ACA resulting in infarction - Displacement of medial temporal lobe due to laterally located masses - Unilateral infarctions of the occipital lobe due to compression of PCA - Lateral flattening of midbrain - Obstructive hydrocephalus resulting from aqueductal and perimesencephalic cisternal compression - Secondary hemorrhages in tegmentum, midbrain, and upper pons (Duret hemorrhage) - Centrally located space occupying lesion - Downward displacement of cerebral hemispheres causing compression of diencephalon and midbrain through tentorial notch - Bilateral infarctions of the occipital lobe due to compression of PCA - Secondary hemorrhages in tegmentum, midbrain, and upper pons (Duret hemorrhage) - Downward displacement of mass lesion in the posterior fossa though foramen magnum leading to medullary compression - Unilateral or bilateral - Inferior descent of the cerebellar tonsils below the foramen magnum - Effacement of the CSF cisterns surrounding the brainstem (cisterna magna) - Obstructive hydrocephalus - Mass lesion in the posterior fossa - Upward displacement of cerebellum through the tentorial opening - Bilateral infarctions of the SCA territories because of SCA compression - Obstructive hydrocephalus due to obstruction of sylvian aqueduct - Penetrating injuries to the skull (e.g., gunshot wound or skull fractures) - The brain prolapses through a fracture or a surgical site in the skull ACA, anterior cerebral artery; PCA, posterior cerebral artery; SCA, superior cerebellar artery; CSF, cerebrospinal fluid. 73
A B Figure 2. Fluid-attenuated inversion-recovery MRI at the lateral ventricles shows the shift of the septum pellucidum from the midline with effacement of the ipsilateral ventricle (A). Fluid-attenuated inversion-recovery MRI at the level of the upper midbrain obtained in the same patient reveals medial temporal lobe herniation downward across the tentorial incisura with effacement of the suprasellar cistern and compression the midbrain (B). 이효과는구획과구획사이의압력차이를발생시키고이로인해뇌조직이한쪽으로이동하면서뇌탈출이발생한다. 뇌탈출은부위에따라대뇌낫밑탈출 (subfalcine herniation), 갈고리이랑탈출 (uncal herniation), 중심탈출 (central herniation), 소뇌편도탈출 (cerebellar tonsillar herniation), 상방탈출 (upward herniation), 머리덮개뼈경유탈출 (transcalvarial herniation) 등으로구분된다 (Fig. 1). 뇌탈출을시사하는징후로는환자의의식변화와대뇌제거경축 (decerebrate rigidity) 이나피질제거경축 (decorticate rigidity) 등의자세이상, 호흡변화, 안구운동장애, 동공변화등이대표적이며각각의부위별로나타날수있는특징적인증상을이해한다면초기치료에도움이될수있다 (Table 1). 1) 대뇌낫밑탈출의증상대뇌낫밑탈출은띠이랑탈출 (cingulate herniation) 이라고도불리며뇌탈출중가장흔하다. 전두와 (frontal fossa) 또는측두와 (temporal fossa) 에덩이가있는경우대뇌낫막아래로띠이랑 (cingulate gyrus) 이밀려서발생하게된다. 대부분의경우증상이없지만, 뇌탈출이심할경우전대뇌동맥의분지인뇌량주위동맥 (pericallosal artery) 을압박하여전두엽뇌경색을유발시킬수있다. 이로인해병변반대쪽반신마비, 의지상실증 (abulia) 이나무운동무언증 (akinetic mutism), 요실금이발생할 수있으며, 반신마비의경우일반적으로는다리와어깨부위가팔과손, 얼굴보다심하게나타난다. 이외에도외측뇌실의몬로공 (foramen of Monro) 의압박으로인해뇌척수액흐름을차단하여폐쇄수두증을유발할수있다. 이로인해병변쪽에는외측뇌실압박소견이, 병변반대쪽에는외측뇌실확장소견과뇌실주위백질의저음영이영상에서관찰될수있다. 7 변화를관찰하기위해서중심선에서투명중격 (septum pellucidum) 의이동정도를반복측정을한다 (Fig. 2). 2) 갈고리이랑탈출의증상갈고리이랑탈출은두번째로흔한뇌탈출로천막경유탈출 (transtentorial herniation) 이라고도한다. 주로한쪽두정엽혹은측두엽병터에의한부피증가로뇌압이상승하게되고이러한국소적인뇌압의상승은중뇌를뇌압이낮은아래쪽으로이동시키게되고동시에내측측두엽의갈고리이랑와해마가천막을통과하게된다. 이때중뇌의상행망상체활성계 (ascending reticular activating system) 장애로인해의식변화가발생할수있으며, 동측의제3뇌신경 ( 눈돌림신경 ) 을압박하여안구운동마비 ( 눈의바깥쪽아래로편향 ) 와동측의동공확장 (Hutchinson pupil) 도발생가능하다. 동측의후대뇌동맥의압박으로인해반대쪽동측반맹 (contralateral homonymous hemianopsia) 이생길수도있다. 편측마비는병변쪽이나병 74
Jeong-Ho Hong Intracranial hypertension and herniation syndrome A B C Figure 3. Central herniation. Gradient echo image (A) shows subdural hemorrhage in bilateral cerebral convexity with mass effect causing compression of bilateral ventricles. Fluid-attenuated inversion-recovery (B) and gradient echo MRI (C) obtained at the level of the midbrain indicate herniation of the uncus and hippocampus inferiorly and medially. Anterior lobe of cerebellum appears at the upper level of the midbrain due to inferior displacement of the midbrain through the tentorial incisura. Entire quadrigeminal and suprasellar cisterns are effaced. Secondary hemorrhages (Duret hemorrhage) in midbrain are shown. 변반대쪽모두에서생길수있는데, 병변반대쪽마비는동측의대뇌다리 (cerebral peduncle) 의압박에의해서발생하며, 병변쪽마비는병변반대쪽대뇌다리가병변반대쪽천막패임 (tentorial incisura) 에눌려 (Kernohan s notch) 발생한다. 특히, 후자를 Kernohan s notch 증후군혹은거짓국소화징후 (false localizing sign) 라고부른다. 8 탈출정도가심할경우대뇌제거경축과중추신경인성과호흡이발생하기도한다. 간혹뇌기저동맥의관통동맥 (perforating artery) 들이신전되거나찢어지며이차적으로중뇌에출혈이일어나게되는데, 이를 Duret 출혈이라고한다. 9 영상소견으로초기에는병변측안장위수조 (suprasellar cistern) 가소멸되고전교뇌수조 (prepontine cistern) 와소뇌교뇌각수조 (cerebellopontine angle cistern) 에확장소견이관찰된다. 이후해마가천막의내측아래방향으로내려오게되고사구수조 (quadrigeminal cistern) 의압박과함께중뇌가병변반대측천막패임방향으로눌리는소견이관찰된다. 심할경우안장위수조와사구수조의소멸되고거의정중선에까지측두각 (temporal horn) 이위치하는것이관찰된다 (Fig. 2). 7,10 3) 정중탈출의증상정중탈출은천막탈출 (tentorial herniation) 이라고도하며좌우대뇌의대칭적인병변이뇌압의경사로인해중뇌사이뇌이음부 (diencephalon) 나상부뇌간이수직방향으로아래로밀려천막패임을넘어편위된상태이다. 증상역시주로양측성으로발생하며중뇌사이뇌이음부와상부뇌간의압박에의해양측성눈돌림신경마비, 바깥눈근육마비, 양측추체로장애로양 측사지마비, 대뇌제거경직, 의식장애와호흡장애가생길수있다. 또한, 양측후대뇌동맥의압박에의한양측후두엽뇌경색이, 윌리스고리에서나오는작은관통동맥들이압박되어시상하부와기저핵주위에뇌경색이발생할수있다. 11 Duret 출혈이갈고리이랑탈출에서보다더흔히관찰되며심할경우뇌사로진행될수도있다. 하지만일반적으로점거성병변이양측성혹은정중부에존재하는경우는드물기때문에처음부터정중탈출만발생하는경우는드물고, 대개갈고리이랑탈출과함께발생하게된다. 영상소견으로는초기에는뇌바닥수조 (basal cistern) 는소멸되고시상하부와시신경교차 (optic chiasm) 가터키안장 (sella turcica) 쪽으로밀리게되며, 심해지면중뇌와교뇌사이각이 90도에서 0도로서서히줄게된다 (Fig. 3). 12 4) 소뇌편도탈출의증상소뇌편도탈출은후두개와 (posterior fossa) 병변의부피증가로소뇌편도가아래쪽으로이동하면서두개골의큰구멍을지나연수를누르게된다. 두개내압상승때요추천자로뇌척수액배액을하는경우간혹발생할수있다. 증상으로는연수주위의상행망상체활성계의손상으로의식저하가진행하고하부뇌신경장애로목주위통증과강직, 추체외로손상으로근긴장도저하, 연수주위의호흡중추와혈관운동중추의손상으로실조성호흡 (ataxic breathing) 과불규칙한맥박, 혈압의변화가관찰될수있다. 소뇌충부 (cerebellar vermis) 의압박으로주기교대안진 (periodic alternating nystagmus) 가관찰되기도하며이외에도현훈, 구음장애, 삼킴곤란등뇌간압박증 75
상이나타나게된다. 영상학적으로도뇌간주위수조, 특히대수조 (cisterna magna) 의소멸이관찰되며시상면영상 (sagittal image) 로보면소뇌편도또는소뇌하부가큰구멍아래에서관찰된다. 일반적으로편도가큰구멍 5 mm 아래에서관찰된다면이상소견으로간주한다. 7,13 폐쇄성수두증도흔히동반된다. 선천성기형중제1형 Chiari 기형에서도소뇌편도탈출이관찰되나이경우임상증상이비특이적이고생명에크게위협적이지는않다. 14 뇌탈출로인한국소부위의손상과주위뇌혈관의압박으로인한이차적인뇌허혈등이유발된다. 특히, 뇌탈출이일어나면국소부위의순환장애뿐만아니라뇌간의압박에의해갑자기생명유지가곤란해질위험이발생할수있기때문에뇌탈출증후가발견되었다면가능한한빨리뇌영상촬영이시행되어야하고동시에두개강내압을낮추는적극적인치료가함께이루어져야한다. 5) 상방탈출의증상상방탈출은천막위압력보다후두개와의압력이빠르게증가하는경우뇌간이천막패임을통과해위로밀려올라가면서나타나는현상이다. 주로후두개와에생긴종양이나뇌졸중의부피증가가원인이다. 후두개와의병변이커지면소뇌충부가천막위로밀려올라가며, 중뇌와위소뇌동맥 (superior cerebellar artery) 을압박하여상부소뇌경색이발생할수있다. 증상으로는혼수상태로빠질수있으며, 동공은축동되고, 온수안진반응이소멸되거나대뇌제거경축자세등이관찰될수있다. 15 실비우스수도관 (sylvian aqueduct) 을압박할경우급성폐쇄수두증도유발될수있다. 7,16 이때폐쇄수두증치료를위해응급으로뇌실외배액술 (extraventricular drainage) 을시행하면오히려상방탈출이악화될수있기때문에주의를해야한다. 6) 기타뇌탈출들머리덮개뼈경유탈출은외측탈출 (external herniation) 이라고도불리며두개골골절이나구개골수술부위를통해두개내압상승으로탈출및압착되는것으로두개절제술시발생할수있다. 7 이외드물지만경질막경유탈출 (transdural herniation) 혹은두개경유탈출 (transcranial herniation) 은머리덮개뼈경유탈출과달리두개골골절시파편등이두개골내로들어가면서경질막이찢겨지며이부위로경질막내의뇌조직이탈출되는경우이다. 천두술 (burr hole trephination) 이나두개절제술, 개두술시발생할수있으며, 드물지만발생시크기나범위에따라상당히위험할수있다. 결론 신경계중환자실에서는흔히접하는단일뇌병변은심해지면두개내압상승뿐만아니라덩이효과로인한뇌탈출을유발하게된다. 두개강내압의증가는뇌관류압의저하를일으키고 REFERENCES 1. Sanders MJ, Lewis LM, Quick G, McKenna K. Mosby s paramedic textbook, 2nd ed. Chapter 22. Head and Facial Trauma 2001. 2. Fodstad H, Kelly PJ, Buchfelder M. History of the cushing reflex. Neurosurgery 2006;59:1132-7; discussion 1137. 3. Pasztor E, Fedina L, Kocsis B, Berta Z. Activity of peripheral sympathetic efferent nerves in experimental subarachnoid haemorrhage. Part I: Observations at the time of intracranial hypertension. Acta Neurochir (Wien) 1986;79:125-31. 4. Hackett JG, Abboud FM, Mark AL, Schmid PG, Heistad DD. Coronary vascular responses to stimulation of chemoreceptors and baroreceptors: evidence for reflex activation of vagal cholinergic innervation. Circ Res 1972;31:8-17. 5. Cushing H. Peptic ulcers and the interbrain. Surg Gynecol Obstet 1932;68:1-37. 6. Kalmar AF, Van Aken J, Caemaert J, Mortier EP, Struys MM. Value of Cushing reflex as warning sign for brain ischaemia during neuroendoscopy. Br J Anaesth 2005;94:791-9. 7. Laine FJ, Shedden AI, Dunn MM, Ghatak NR. Acquired intracranial herniations: MR imaging findings. AJR Am J Roentgenol 1995;165:967-73. 8. Namura S, Kang Y, Matsuda I, Kamijyo Y. Magnetic resonance imaging of sequelae of temporal lobe herniation secondary to traumatic acute subdural hematoma: Kernohan's notch and posterior cerebral artery territory infarctions contralateral to the supratentorial lesion--case report. Neurol Med Chir (Tokyo) 1997;37:32-5. 9. Parizel PM, Makkat S, Jorens PG, Ozsarlak O, Cras P, Van Goethem JW, et al. Brainstem hemorrhage in descending transtentorial herniation (Duret hemorrhage). Intensive Care Med 2002;28:85-8. 10. Hacke W, Schwab S, Horn M, Spranger M, De Georgia M, von Kummer R. 'Malignant' middle cerebral artery territory 76
Jeong-Ho Hong Intracranial hypertension and herniation syndrome infarction: clinical course and prognostic signs. Arch Neurol 1996;53:309-15. 11. Endo M, Ichikawa F, Miyasaka Y, Yada K, Ohwada T. Capsular and thalamic infarction caused by tentorial herniation subsequent to head trauma. Neuroradiology 1991;33:296-9. 12. Stovring J. Descending tentorial herniation: findings on computed tomography. Neuroradiology 1977;14:101-5. 13. Ishikawa M, Kikuchi H, Fujisawa I, Yonekawa Y. Tonsillar herniation on magnetic resonance imaging. Neurosurgery 1988;22(1 Pt 1):77-81. 14. Bindal AK, Dunsker SB, Tew JM Jr. Chiari I malformation: classification and management. Neurosurgery 1995;37:1069-74. 15. Cuneo RA, Caronna JJ, Pitts L, Townsend J, Winestock DP. Upward transtentorial herniation: seven cases and a literature review. Arch Neurol 1979;36:618-23. 16. Osborn AG, Heaston DK, Wing SD. Diagnosis of ascending transtentorial herniation by cranial computed tomography. AJR Am J Roentgenol 1978;130:755-60. 77