KOR J CEREBROVASCULAR SURGERY September 2011 Vol. 13 No 3, page 194-200 연세대학교의과대학강남세브란스병원신경외과학교실 Cerebral Bypass Surgery for Treating Unclippable and Uncoilable Aneurysms Jung Soo Kim Sang Hyuk Park Chang Ki Hong Jun Suk Huh Hyoung Lae Kang Jin-Yang Joo Department of Neurosurgery, Yonsei University College of Medicine, Gangnam Severance Hospital ABSTRACT OBJECTIVE : Fusiform and dissecting aneurysms cannot be treated with conventional clipping or coiling surgery. Various methods are used for treating these aneurysms, including proximal occlusion of the parent artery or trapping the aneurysms with or without cerebral revascularization. We report here on our experience with treating unclippable and uncoilable aneurysms and we present the clinical and angiographic outcomes. METHODS : Nine patients with unclippable and uncoilable aneurysms were managed during a 5 year period at our institution. We retrospectively reviewed all the patients with aneurysms and who underwent multimodal techniques. The mean age of the 9 patients was 56.5 years. The mean clinical follow-up period was 28.1 months. Six patients presented with subarachnoid hemorrhage and 2 had diplopia. Of these patients, 3 had aneurysms arising from the posterior inferior cerebellar artery (PICA), 2 had vertebral artery (VA) aneurysms, 2 had internal carotid artery aneurysms and 2 had middle cerebral artery aneurysms. Eight aneurysms were fusiform and 1 was a giant saccular aneurysm. RESULTS : The treatment included surgical trapping with bypass in 4 patients, endovascular trapping with bypass in 4 patients and vein graft bypass in 1 patient. Among the bypass surgeries, high-flow bypass was performed for a giant internal cerebral artery (ICA) aneurysm. Trapping of the aneurysms with coil and occipital artery (OA)-PICA bypass were performed for 2 VA aneurysms of the PICA origin. There was no recurrent bleeding or ischemic symptoms during the follow-up periods. CONCLUSION : The cerebral bypass technique is a useful, safe for the treatment of dissecting and otherwise unclippable/uncoilable aneurysms. (Kor J Cerebrovascular Surgery 13(3):194-200, 2011) KEY WORDS : Dissecting aneurysm Bypass Trapping 서론 논문접수일 : 2011년 7월 22일 심사완료일 : 2011년 8월 6일 교신저자 : Jung Soo Kim, Department of Neurosurgery, Yonsei University College of Medicine, Gangnam Severance Hospital 211, Unjuro, Gangnamgu, Seoul, 135-720, Korea Tel : (02) 2019-3390 Fax : 02-3461-9229 Email : jheaj@hanmail.net 뇌동맥류의가장적절한치료는모혈관 (parent vessel) 으로부터동맥낭 (aneurysmal sac) 으로가는혈류를차단하는것이다. 이를위해수술적동맥류결찰술과혈관내코일색전술이발전되었다. 8)21) 최근급속하게 194
Table 1. Clinical features of the patients. No. SEX/Age Presentation H-H Gr Aneurysm location Aneurysm morphology Treatment modality Complication mrs 1 M/38 Infarction 0 PICA Dissecting EVT + Bypass none 0 2 M/54 SAH 3 PICA Dissection S trap + Bypass none 0 3 M/29 incidental 0 PICA Fusiform S trap + Bypass skin necrosis 0 4 F/52 SAH 2 VA-PICA Dissecting S trap + Bypass none 0 5 F/32 SAH 3 VA Dissecting EVT + Bypass CSF leakage 1 6 M/62 headache, SAH 1 VA Dissecting EVT + Bypass none 0 7 F/65 Diplopia 0 ICA Giant High flow Bypass none 2 8 F/61 SAH 2 Distal MCA Fusiform in-situ Bypass none 0 9 F/54 Incidental 0 M2-3 Fusiform S trap + Bypass none 0 H-H Gr= Hunt-Hess grade; mrs= modified Rankin Scale; SAH= subarachnoid hemorrhage; PICA= posterior inferior cerebellar artery; VA= vertebral artery; ICA= internal carotid artery; MCA= middle cerebral artery; EVT= endovascular treatment; S trap= surgical trapping; CSF= cerebrospinal fluid Table 2. Treat ment modality and Clinical outcome Treatment modality Aneurysm location and characteristics Cases Surgical trapping after OA-PICA bypass VA dissecting An 2 PICA dissecting An 1 PICA fusiform An 1 Endovascular trapping after OA-PICA bypass VA dissecting An 1 PICA dissecting An 1 Endovascular trapping after ECA-M2 bypass ICA giant An 1 In-situ bypass with Y-shaped vein graft *Distal M3 fusiform An(due to Myxoma) 1 Surgical trapping after STA-M3 bypass Distal M2 fusiform An 1 OA= occipital artery; PICA=posterior inferior cerebellar artery; ECA= external carotid artery; STA= superficial temporal artery; VA= vertebral artery; An= aneurysm; ICA= internal carotid artery. *In this case, we performed the direct aneurysmectomy due to embolic myxomatous aneurysm from cardiac myxoma. 발전하는다양한동맥류의치료법들로대부분의동맥류가이러한방법으로치료가가능하다. 그러나일부거대 (giant) 동맥류와위험한곁가지 (perforators) 혈관을가진방추형 (fusiform) 동맥류, 석회화된목을가진큰동맥류등은전통적인결찰술또는코일색전술로치료하기어려운경우가있다. 이러한동맥류의치료를위해모동맥근위부폐색술 (proximal occlusion of parent artery) 과혈관우회문합술 (cerebral bypass surgery) 등의치료법들이동원되고있다. 저자들은결찰술이나코일색전술단독으로치료가불가능한전방순환계와후방순환계동맥류들을혈관문합술을이용하여치료한경험을보고하고자한다. 대상및방법 환자선택 2008년 6월부터 2010년 7월까지 446명의동맥류환자가 클립이나코일로치료를받았다. 환자들의의료기록을검토하여결찰술이나코일같은일반적 (conventional) 치료가불가능하다고판단하여혈관문합술과모혈관폐색으로치료한 9명의환자를대상으로하였다 (Table 1). 환자들은남자 5명과여자 4명으로평균연령은 56.5세 (27~64세) 이며평균 28.1개월 (4~84개월) 을추적관찰하였다. 5명의환자는뇌지주막하출혈 (subarachnoid hemorrhage) 로내원하였고 2명은건강검진에서우연히발견되었다. 1명은뇌신경압박으로인한복시 (diplopia) 증상, 1명은뇌경색으로내원하였다. 뇌지주막하출혈환자의 Hunt-Hess grade는 3점 2명, 2점 2명, 1점 1명이었다. 각동맥류의위치는후방순환계에 5례로후하소뇌동맥 3례, 척추동맥 2례이며전방순환계에는 4 례로내경동맥 2례, 중대뇌동맥 2례였다. 동맥류의형태로는대부분박리성동맥류 (5례) 였으며방추형동맥류가 3례거대동맥류가 1례씩있었다. Kor J Cerebrovascular Surgery 13(3):194-200, 2011 195
A B C Fig. 1. A case of 32-year-old female who presented with headache. (A) Lateral right vertebral angiography shows a fusiform dissecting aneurysm involving the right posterior inferior cerebellar artery (PICA). (B) The intraoperative photograph shows the end-to-side anastomosis of the occipital artery (OA)-PICA. Note the end of the OA was sutured to the side of the cortical segment of the PICA. (C) Postoperative anterioposterior right vertebral angiography shows total occlusion of the distal vertebral artery and PICA 수술전검사모든환자에서수술전내과적검사와뇌전산화단층촬영 (computed tomography : CT), 전산화단층촬영혈관조영 (computed tomography angiography : CTA), 뇌혈관조영검사 (4-vessel angiography) 를실시하였고가능한경우는뇌자기공명영상 (Magnetic resonance imaging : MRI) 와자기공명영상혈관조영 (Magnetic resonance imaging angiography : MRA) 를실시하였다. 모동맥폐색수술이결정되면뇌혈류량의부족분을예측하기위해내경동맥의풍선폐색검사 (balloon test occlusion : BTO) 나병변부경동맥압박검사후뇌혈관조영검사를시행해측부순환을관찰했다. 저혈압유발검사는 b-blocking agents (Labetalol) 를 10~50 mg를 1분동안정맥주사하여기저평균동맥압의약 20~30% 정도의저혈압을유발해환자의신경학적이상을관찰한후에혈관문합여부를결정하였다. 단일광자방출전산화단층촬영 (Single-photon emission computed tomography : SPECT) 는실제혈류부족분에대한정확한검사가될수있으나파열된동맥류환자는실시하지않았다. 대동맥류는고혈류문합이필요한상태로앙와위 (supine) 에서테리온접근법 (pterional approach) 과경동맥분지부노출하여외경동맥 (external carotid artery: ECA)-M2 문합후코일색전술을하였다 (Fig. 2). 원위부중대뇌동맥분지 (M3) 에발생한방추형동맥류는뇌항법장치를이용하여동맥류위치를확인한후개두술을시행하고동맥류절제후 Y자모양의요골정맥이식혈관을이용하여문합을시행했다 (Fig. 3). 원위부중대뇌동맥 (M2) 에발생한방추형동맥류는얕은측두동맥 (superficial temporal artery : STA) 의위치를고려하여두피절개와개두술을시행후 STA-M3 혈관문합을한뒤동맥류를포획하였다. 모혈관폐색을위한방법은혈관문합수술시문합혈관의기능이좋고동시에클립으로폐색이가능하면수술적폐색을하였고그렇지않는경우시간적차이를두고코일을이용한폐색방법을선택했다. 또한급성문합부전을예방하기위해수시로 indocyanine green video angiography로혈류를확인하고봉합시에도수시로도플러로혈류를확인했다. 치료방법치료방법과임상적결과는 Table 2에요약하였다. 후방순환계에발생한 6례의동맥류는모두측와위 (park bench position) 에서 unilateral suboccipital retrosigmoid approach 후에 Occipital artery (OA) -Posterior inferior cerebellar artery (PICA) 문합후모혈관폐쇄로치료했다. 모혈관폐쇄방법으로문합술과동시에클립포착술이 4례이며, 코일포착술 2례시행했다 (Fig. 1). 전방순환계동맥류중 Internal carotid artery (ICA) 거 수술후관리수술후환자는중환자실에서약 2일정도지속적인혈압관찰과혈장대용액 (Volume Expanders) 과승압제를이용하여평균동맥압보다약 10% 정도고혈압을유지하였고출혈의위험이낮아지는 3일부터 aspirin 을투여하였다. 이식혈관문합부전을막기위해상처소독이나환자자세유지에도이식혈관근위부에압박을피했으며수시로혈관도플러를이용하여근위부혈류를확인했다. 영상검사는수술후 1일째뇌 196 Kor J Cerebrovascular Surgery 13(3):194-200, 2011
A B C D Fig. 2. A case of 65-year-old female who presented with diplopia due to sixth nerve palsy. (A) Anteroposterior left internal carotid artery (ICA) angiography shows a giant aneurysm in the carvenous ICA (3.5 x 4.1 x 3.2 cm). Note the right ICA was occluded due to the treatment of a right paraclnoid aneurysm. (B) Intraoperative photograph shows the end-to-side anastomosis of the saphenous vein-m2. Note the end of the saphenous vein was sutured to the side of M2. (C) The intraoperative photograph shows end-to-end anastomosis of the external carotid artery (ECA) -saphenous vein. Note the end of the saphenous vein was sutured to the end of the ECA. Another ECA stump was sutured. (D) Postoperative anterioposterior ECA angiography shows patency of the bypass and filling of the MCA territory. CT, CTA를시행하여문합혈관의기능을확인했으며퇴원시뇌혈관조영검사 (Disital subtraction cerebral angiography : DSA) 로다시한번더확인하였고수술후 1년째뇌혈관조영검사 (DSA) 을시행하였다. 외래정규검사로수술후약 6개월에 MRA와 1년에혈관조영검사를시행하여문합혈관의혈류와동맥류의폐색상태및신생혈관의분포등을확인했다. 결과 Treatment results 수술을시행한환자에서대부분이후방순환계의 OA- PICA bypass로성공적으로시행되었고모든환자에서 Temporary clip 5분전에 Thiopental sodium 250 mg 정맥 주사후뇌보호를하며최대한 Temporary clip 시간을줄여급성뇌경색같은합병증은발생하지않았다. In-situ bypass를제외한모든환자에서모혈관의폐쇄가이루어졌는데각각코일과클립으로시행한모혈관의폐쇄도잘시행되었고이차적으로발생한뇌경색의증상은없었다. Clinical results 모든환자에서급성혈관문합부전은발생하지않았으며신경학적후유증없이회복하였으며퇴원시환자들의 mrs (modified Rankin scale) 는대부분 0점이었다. 치료후각각 1례의피부괴사와뇌척수액유출이발생했지만모두회복가능하였고수술후환자의신경학적증상은회복되었다. Kor J Cerebrovascular Surgery 13(3):194-200, 2011 197
A B C D Fig. 3. A case of a 54-year-old female who presented with headache and dysarthria due to embolic infarct secondary to cardiac myxoma. (A) The three-dimensional angiogram shows a fusiform aneurysm involving the cortical MCA branch. (B) Intraoperative photograph shows a fusiform aneurysm at the cortical branch of the MCA. (C) Intraoperative photograph of the harvested radial vein. (D) Intraoperative photograph shows in-situ end-to-end anastomosis of the MCA branch. 수술후 1일째시행한 CTA에서문합혈관의혈류를확인했으며클립결찰과 In-situ 정맥이식문합을시행한 5예에서는퇴원전에실시한혈관조영검사 (DSA) 에서도혈류를확인할수있었다. 외전신경마비증상으로내원한내경동맥의거대동맥류환자는 10년전에우측내경동맥근위부 (paraclinoid) 동맥류치료를위해우측내경동맥폐색된상태로우측중대뇌동맥영역의혈류가부족하였다. 처음치료로혈관내코일색전술을시행하였으나실패하여고혈류혈관문합이필요했으며문합술후코일을이용하여모혈관폐색을동맥류의근위부와원위부에각각시행하였다. 퇴원당시동맥류의종괴효과가줄어들어외전신경마비증상이호전되었다. 혈관문합후코일폐색술을시행한다른환자들도코일폐색시에시행한혈관조영검사 (DSA) 에서모두문합혈관의혈류를확인했다. 고찰 동맥류의치료로고전적으로개두술후단순클립으로결찰하는방법이많이이용된다. Sugita는 4cm이넘는 크기의다양한클립으로거의모든거대동맥류를치료하였으나클립이불가능한목이없는방추형이나박리성동맥류에대해서는한계가있었다. 22) 최근까지거대동맥류치료에직선클립 (straight clip), 유창클립 (fenestrated clip) 등의다양한종류와모양의클립을복합적으로이용하여치료한결과를보고하였다. 10) 코일색전술은 1970년대중반에도입되고 1995년에미국 FDA 승인후에고식적결찰술과더불어동맥류치료에큰역할을하고있다. 8) 최근다양한 stent의발전과두개이상의 catheter를동시에사용하여색전술을시도하여현재까지코일이불가능하다고판단되던동맥류목이넓은동맥류역시코일로치료가가능해졌다. 1)5)7) 아직까지도중요한곁가지를가지는거대동맥류와동맥류목이존재하지않는방추형및박리성동맥류들은여전히코일이나클립같은고전적인치료방법으로치료가불가능하다. 이런클립이불가능한동맥류에대해다양한 wrapping 기술들을보고하며저자마다 cotton, 근육, 근막, gauze, Teflon, surgical glue 등의다양한물질로결과를보고하였다. 그러나 wrapping의가장큰문제점은재출혈의위험이상당이높으며저 198 Kor J Cerebrovascular Surgery 13(3):194-200, 2011
자들마다 0% 에서 17% 의출혈율을보고하여치료에는한계가있다. 3)4)6)13)24) 특히내경동맥의박리성동맥류의 wrapping 치료는약 42% 의재출혈이나동맥류의성장을보고하여치료의효과가의문시되었다. 16) 후방순환계의박리성동맥류는대부분허혈성증상으로내원하여스텐트나코일을이용한혈관내수술과항혈소판제제나항응고제의약물적치료로좋은결과를보고한다. 2)11) 그러나뇌지주막하출혈로내원한환자는재출혈율이높으며재출혈시사망률이매우높아초기에적극적인치료를요한다. 9)14) 동맥류의단순클립이나코일로치료가불가능하며 wrapping으로도안전성이확보가안되는내경동맥 dorsal wall 동맥류나거대동맥류들을수술이나코일을이용한혈관폐색의치료법으로치료하였다. 12)15) 혈관폐색으로치료하기전에모두풍선폐색검사 (Balloon test occlusion : BTO) 나뇌단일광자방출전산화단층촬영 (single-photon emission computed tomography : SPECT) 등으로혈관폐색에대한혈류감소후에뇌경색의위험을충분히검사한후에만실시할수있었다. BTO 검사에신경학적이상이나타나거나 SPECT에서혈류부족이확인되면혈관폐색만으로는치료가될수없고혈관문합술후동맥류모혈관폐색하는치료법들이또한가지의치료방법으로시행하고있다. 거대동맥류나방추형동맥류, 동맥류 base 부분에중요곁가지를가지는동맥류, 석회화나동맥경화로단순클립이위험한복잡한중대뇌동맥동맥류를해부학적위치와혈류필요량에따라혈관문합후모혈관폐색이나클립결찰술을보고하였다. 17)20)25) 저자들도최대한정상혈류방향을유지하기위해결찰술이나코일색전술을먼저선택 (first choice) 하여가능한방법을연구했으며불가능하다고판단하거나처음시도에서실패한경우모동맥폐색및혈관문합방법을선택하였다. Sundt 등에의해긴복제정맥 (long saphenous vein) 이식이소개되고이를동맥류치료에도이용되고있다. 23) 복제정맥은장기적폐색율이높고수혜부혈관과혈관내경의크기가잘맞지않는등의단점이있지만다양한길이로박리할수있고 110 ml/min 이상의고혈류를공급할수있어 EC-IC (Extracranial-intracranial) 혈관문합에서 ICA 및근위부 Middle cerebral artery (MCA), Anterior cerebral artery (ACA) 의다양한부위의혈관문합에이용되고있다. 18)19) 저자들은고혈류문합술이필요한경우복제정맥과요골정맥을모두이용하는데복제정맥의길이가길어박리할때와문합할때편하였다. 반면에요골동맥은문합혈관과직경이 비슷한장점이있는반면길이가짧을경우가있으며동맥의특성상혈관연축으로인한급성기문합부전이발생한경우가있어선호하지않는다. 저혈류질환의문합치료와는다르게저자들이경험한동맥류치료에시행한문합술에서는수술후과혈류증후군의증상이없었으며오히려평균동맥압보다약 10% 정도높게유지하여저혈류로인한뇌경색을예방하려했다. 혈관문합술의가장심각한합병증은급성기문합부전으로저자들은문합부전을예방하기위해이식혈관의충분한 heparin 세척, 문합시이식혈관의꼬임과장력을예방하고최대한이식혈관의내피 (intima) 의손상을방지하기위해봉합시내피를 forcep으로잡지않고최대한혈관조작 (manipulation) 을줄인다. 또한급성혈관연축을예방하기위해 papaverin 으로충분히세척하고수술중 indocyanine green video angiography로혈류를확인하고봉합시에도수시로혈관도플러로혈류를확인한다. 대부분마지막피부봉합후마지막으로혈관도플러로이식혈관의근위부혈류를확인하면문합부전은일어나지않았다. 수술후이식혈관의압박이없게환자자세나상처소독하는것도중요하였다. 결론 뇌동맥류를치료하기위해단순클립이나코일의치료방법을넘어다양한 (Multimodal treatment) 수술방법과기술을동원하여치료한다. 필요에따라모혈관을폐색이필요한동맥류는치료의위험과치료후환자의상태에대한충분한수술전검사가필요하다. 혈관문합술은안전하며신경학적장애를남기지않고폐색혈관에충분한혈류를공급할수있으며단순클립이나코일로도치료가불가능하고모혈관의폐색이필요한동맥류치료에꼭필요한수술법이다. REFERENCES 1) Akgul E, Aksungur E, Balli T, Onan B, Yilmaz DM, Bicakci S et al. Y-stent-assisted coil embolization of wide-neck intracranial aneurysms. A single center experience. Interv Neuroradiol. 17:36-48, 2011. 2) Arnold M, Bousser MG, Fahrni G, Fischer U, Georgiadis D, Gandjour J et al. Vertebral artery dissection: presenting findings and predictors of outcome. Stroke 37:2499-503, 2006. 3) Cudlip SA, Kitchen ND, McKhahn GM, Bell BA. Wrapping of solitary ruptured intracranial aneurysms, outcome at five years. Kor J Cerebrovascular Surgery 13(3):194-200, 2011 199
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