대한응급의학회지제 20 권제 4 호 Volume 20, Number 4, August, 2009 원 저 외상성두부손상에서기존뇌동맥류파열의 CT 소견 단국대학교의과대학응급의학교실 박희정 김갑득 CT Findings of Rupture of Pre-existing Cerebral Aneurysm in Blunt Head Trauma Heu Jung Park, M.D., Gab Teog Kim, M.D. 책임저자 : 김갑득충청남도천안시안서동산 16-5 단국대학교의과대학응급의학교실 Tel: 041) 550-6869, Fax: 041) 550-7045 E-mail: gtkim@dankook.ac.kr 접수일 : 2009년 3월 24일, 1차교정일 : 2009년 4월 13일게재승인일 : 2009년 5월 29일 * 이논문은 2008학년도단국대학교대학연구비의지원으로연구되었음. 399 Purpose: Rupture of pre-existing cerebral aneurysms has been reported as a cause of traumatic subarachnoid hemorrhage (TSAH). SAH due to rupture of pre-existing cerebral aneurysm is an important differential diagnosis in TSAH. Our study was aimed to assess whether a rupture in a pre-existing cerebral aneurysm could be predicted on the basis of the quantity and distribution pattern of hemorrhage on the initial computed tomography (CT). Methods: 197 patients with TSAH were retrospectively studied between the years 2003 and 2008. We examined the age and sex of patients, mechanisms of injury, consciousness level at admission, and CT parameters including the distribution and quantity of SAH, localized blood clot, intraventricular hemorrhage, or hemorrhagic contusion and extra-axial hematoma. We compared the patients with nonaneurysmal TSAH to the patients with aneurysmal TSAH. Results: 22(11.2%) patients with TSAH harbored pre-existing cerebral saccular aneurysms. The aneurysms were found in the patients with diffuse or anteriorly located blood in the basal cisterns(40.6%), unilateral sylvian fissure (16.7%), and anterior interhemispheric fissure(18.2%). But the aneurysm was not found in all patients with perimesencephalic hemorrhage, bilateral sylvian fissures, and convexities. TSAH with localized clot in the anterior interhemispheric or sylvian fissure (OR=5.924, p=0.005), or SAH completely filling any cistern or fissure (OR=3.148, p=0.034) was significantly associated with rupture of pre-existing cerebral aneurysm in logistic regression analysis. Conclusion: SAH in the basal cisterns extended into bilateral sylvian fissures and anterior interhemispheric fissure, and SAH in the unilteral sylvian fissure on initial CT could be predicted rupture of pre-existing cerebral aneurysm. Key Words: Subarachnoid hemorrhage, Traumatic, X-Ray Computed tomography, Intracranial aneurysm. Department of Emergency Medicine, College of Medicine, Dankook University, Cheonan, Korea 서 외상성지주막하출혈은중증두부손상의 15~40% 를차지할정도로응급실에서도드물지않게관찰할수있는응급상황이다 1). 지주막하출혈이있을경우없는경우보다예후가불량하지만보다큰문제는외상성지주막하출혈의원인으로기존뇌동맥류의파열이종종발견되고있다는사실이다 2). 따라서응급실에서시행한 computed tomography (CT) 에지주막하출혈이있으면반드시기존뇌동맥류의파열을감별해야한다. Cummings 등 3) 이외상성지주막하출혈환자 60례중 5례 (8%) 를보고하는등드물게증례들을보고하고있지만지금까지외상에의한기존뇌동맥류의파열에관한정확한통계는없다. 그러나뇌동맥류파열에의한지주막하출혈환자의일부는출혈이일어나기이전에두부외상이있었다고한다 4). 뇌동맥류환자의과반수가재출혈로사망하고, 재출혈은첫 1개월이내에발생하기때문에조기에진단을놓쳐적절한치료를받지못하면죽음에이르는불행을겪게된다 5). 뇌동맥류의가장좋은진단방법은 digital subtraction angiogram (DSA) 이지만이는침습적이고신경학적인합병증을유발할수있어최근에는 CT angiography (CTA) 로점점이 론
400 / 대한응급의학회지 : 제 20 권제 4 호 2009 를대체하는추세이다 6). CTA는시행이빠르고, 간편하며, 침습적이지않고, CT 기초검사후곧바로시행할수있으며, 민감도및특이도면에서 DSA와큰차이가없고, 치료방침에많은정보를제공해주며, 응급이용이가능하기때문에응급실에서도뇌동맥류의진단에널리이용되고있다 7-11). 자발성지주막하출혈에서는 CT에서나타난출혈량과분포양상을이용하여뇌동맥류의파열및파열부위를예측하는연구가활발하게이루어지고있다 12,13). 그러나외상성뇌동맥류파열에의한지주막하출혈도자발성뇌동맥류파열과마찬가지로빠르고정확한진단과치료가강조되고있음에도불구하고국내에서의체계적인연구가거의없는실정이다. 이에저자들은본연구를통해외상성지주막하출혈환자에서기존뇌동맥류의파열을예측할수있는 CT소견을알아보고이를이용하여응급실에서의 CTA 시행기준을마련하는데도움을주고자하였다. 대상과방법본연구는 2003년 1월부터 2009년 3월까지본원응급실을통하여입원후치료를받은외상성지주막하출혈환자를대상으로후향적으로시행하였다. 연구기간동안응급실을경유하여 1342명이두부외상으로입원하였고, 그중 310명이외상성지주막하출혈로진단되었다. 외상성지주막하출혈로진단된환자중외상후 24시간이지난다음 CT검사를시행하였거나, CTA를시행하지않았거나, 이송한병원에서시행한초기 CT필름이없거나, 환자의병력상먼저뇌동맥류가파열되고그로인한외상이의심되는경우를제외한 200명을최종대상으로선정하였다. 뇌동맥류파열과두부외상과의전후관계는원칙적으로응급실에내원할때대화가가능한경우 Edlow 14) 의기준에따라갑자기발생한심한두통이나구토및오심, 경부통증, 경부강직등이나타나면뇌동맥류파열에의한두부외상으로판정하여대상에서제외하였고, 대화가가능하지않은경우입원기간중에의식이회복된후에확인하거나퇴원후전화상으로확인하여전후관계를판정하였으며, 지속적으로의식이회복되지않고사고기전상전후관계가불분명한경우도대상에서제외하였다. 대상환자모두응급실및병실에서뇌동맥류를확인하기위하여 CTA를시행하였다. 동맥류는낭상동맥류 (saccular aneurysm) 로제한하였으며, 수술및 DSA로이를확인하였다. 지주막하출혈이 CTA에서발견된뇌동맥류를중심으로확산되어있으면원인이뇌동맥류의파열이라하였고, 뇌동맥류와전혀다른위치에있으면뇌동맥류의파열과관계없는것으로판단하였다. CT 및 CTA의판독은영상의학과전문의 1인과응급의학과전문의 1인이동시에하였고, 판독이서로다른경우상의하여최종결론을내렸다. CTA는 64-slice multi-divisional CT scanner (LightSpeedPro, GE Medical System, Milwaukee, USA) 를이용하였고, 이기종은 3차원고해상의영상매체로서짧은시간내에대동맥궁에서두정부까지한번에촬영이가능하며, 윌리스환이잘보여혈관내수술을시행하기전주요동맥들에대한평가가가능하다. 환자의의무기록과 CT 판독소견을이용하여환자의연령, 성별, 사고기전, 응급실내원당시 Glasgow coma scale (GCS), CT상지주막하출혈의부위, 출혈량및분포양상, 뇌실내출혈의동반, 혈괴나뇌실질내출혈의동반, 뇌좌상및축외혈종의동반등을조사하였다. 출혈부위로는중뇌주위수조 (perimesencephalic cisterns), 기저수조 (basal cisterns), 실비안열 (Sylvian fissure), 전방대뇌반구열 (anterior interhemispheric fissure), 앰비엔트수조 (ambient cistern) 및사구수조 (quadrigeminal cistern), 궁융부 (convexity), 뇌겸 (falx), 뇌천막 (tentorium) 을조사하였다. 기저수조지주막하출혈은출혈이양측실비안열및전방대뇌반구열로확산된미만성출혈과중뇌주위출혈로나누었다. 중뇌주위출혈은중뇌를둘러싼수조즉, 전다리뇌수조 (prepontine cistern), 앰비엔트수조, 사구수조에국한되고전방대뇌반구열및외측실비안열까지확산되지않은경우로정의하였다. 출혈량은한군데이상의지주막하공간이출혈로완전히찬경우를 다량 (thick), 그렇지않은경우를 소량 (thin) 이라고하였다. 혈괴및뇌실질내출혈의동반은뇌동맥류호발부위에 3 5 mm 이상의혈괴가보이거나뇌실질내출혈이보이는경우로정의하였다. 출혈분포양상은 Fisher scale을이용하였다 15). 1. 통계기존뇌동맥류파열에의한외상성지주막하출혈이특정한 CT양상을띠고있는지를알아보고자뇌동맥류가파열한경우 ( 뇌동맥류군 ) 와뇌동맥류파열과관계없는경우 ( 비-뇌동맥류군 ) 의 CT소견을비교하였다. 연속변수는 t-test, 카테고리변수는 x2-test나 Fisher s exact test 로검정하였고, 뇌동맥류파열을독립적으로예측할수있는인자에대한검정은로지스틱회귀분석을이용하였으며, p값이 0.05미만이면통계적으로유의하다고정의하였다. 결과 1. 환자의임상적특성대상환자 200명의평균연령은 54.2±18.7세이었으며, 65세이상이 31.0% 를차지하였다. 뇌동맥류군 의평균
박희정외 : 외상성두부손상에서기존뇌동맥류파열의 CT 소견 / 401 연령은 60.3±15.7세, 비-뇌동맥류군 의평균연령은 53.5±19.0세이었고, 65세이상은 뇌동맥류군 의 47.6%, 비-뇌동맥류군 의 29.1% 로나타나두군간의유의한차이가없었다 (p=0.082). 남성이여성보다많았고 (60.5% vs 39.5%), 뇌동맥류군 은남성과여성에서비슷하게나타났다 (8.3% vs 13.9%)(p=0.202). 전체환자의평균 GCS는 11.3±4.0이었고, 3~8점이 31.0%, 9~13점이 21.5%, 14~15점이 47.5% 로나타나경도손상이중증및중등도손상보다약간더많았다. 뇌동맥류군 은중증, 중등도, 경도의비율이각각의 28.6%, 19.1%, 52.3% 이었고, 비-뇌동맥류군 은각각의 31.3%, 21.8%, 46.9% 로나타나두부손상의중증도에서두군간의유의한차이가없었다 (p=0.892). 많은경우에교통사고 (64.0%) 나넘어져서 (21.5%) 발생하였고, 추락 (7.0%) 과폭행 (4.5%) 에의한경우는적었다. 뇌동맥류군 은주로교통사고 (76.2%) 나폭행사고 (14.3%) 에서많았고, 추락사고에서는한례도없었다 (p=0.051). 이상과같이 뇌동맥류군 과 비-뇌동맥류군 의연령, 성별, 두부손상의중증도및사고기전에서유의한차이가없었다 (p>0.05)(table 1). 2. 외상에의한뇌동맥류파열의 CT소견대상환자 200명중 21명 (10.5%) 에서뇌동맥류파열에의한지주막하출혈이발생하였으며, 뇌동맥류는모두윌리스환에위치하였고, 19명 (90.5%) 은전방부순환에, 2명 (9.5%) 은후방부순환에있었다. 그리고다른 6명에서는지주막하출혈과관련이없는것으로추정되는뇌동맥류가발견되었다. 내경동맥류의파열은뇌기수조의출혈 (2 례 ) 과기저실비안열의출혈 (2례), 전뇌동맥류의파열은전방대뇌반구열의출혈 (2례) 과실비안열의파열 (2례), 전교통동맥류의파열은기저수조의출혈 (3례), 후교통동맥류의파열은기저실비안열의출혈 (1례), 중뇌동맥류의파열은기저수조의출혈 (4례) 과실비안열의출혈 (5례), 후방부순환동맥류의파열은기저수조의출혈 (2례) 을유발하였다. 뇌실내출혈은제 4뇌실과측뇌실에각각 6례로가장많았고, 뇌실내출혈을잘유발하는특정한뇌동맥류파열은없었다 (Table 2). 지주막하출혈의부위는뇌동맥류파열을예측하는데아주중요한인자로작용하였다 (p=0.000, x 2 value= 11.557). 뇌동맥류는주로양측실비안열이나전방대뇌반구열에확산된기저수조의출혈, 한쪽실비안열에국한된출혈, 전방대뇌반구열에국한된출혈에서발견되었고 (35.5%, 17.8%, 16.7%)(Fig. 1), 궁융부에국한된출혈, 기저수조출혈이동반되지않은양측실비안열의출혈, 중뇌주위에국한된출혈에서는뇌동맥류를발견할수없었다 (Fig. 2). 또한 뇌동맥류군 은출혈이윌리스환에국한되거나 (42.9%) 윌리스환과궁륭부에확산되어나타났다 (57.1%)(Table 3, 4). 지주막하출혈이궁융부에국한된경우에는뇌동맥류를전혀발견할수없어이들을제외한 134명의기저수조및실비안열의출혈환자를대상으로뇌동맥류파열을예측할수있는 CT소견을알아보고자하였고, 이를위해출혈부위, 출혈량, 뇌동맥류호발부위에서의혈괴및뇌실질내출혈, 혈성뇌좌상이나축외혈종의여부를조사하였다. 단변량분석에서출혈부위 (p=0.001, x 2 =17.916), 출혈량 (p=0.003, x 2 =8.645), 혈괴및뇌실질내출혈의동반 (p=0.001, x 2 =11.705) 에서두군간의유의한차이가있었고, 뇌실내출혈의동반 (p=0.060, x 2 =3.535) 과혈성뇌 Table 1. Characteristics for patients with traumatic SAH Variables Definition Total (%) Aneurysmal group (n=21) Non-aneurysmal group (n=179) p-value* Age Mean±SD 54.2±18.7 60.3±15.7 53.5±19.0 0.115 <65 yrs 138 (69.0) 11 (08.0) 127 (92.0) 0.082 65 yrs 062 (31.0) 10 (16.1) 052 (83.9) Sex Male 121 (60.5) 10 (08.3) 111 (91.7) 0.202 Female 079 (39.5) 11 (13.9) 068 (86.1) GCS on Mean±SD 11.3±4.00 11.1±4.70 11.3±4.00 0.898 admissison 03-80 062 (31.0) 06 (09.7) 056 (90.3) 0.892 09-13 043 (21.5) 04 (09.3) 039 (90.7) 14-15 095 (47.5) 11 (11.6) 084 (88.4) Mechanism MVA 128 (64.0) 16 (12.5) 112 (87.5) 0.051 of injury Fall 014 (07.0) 0 (0) 14 (100) Slip 043 (21.5) 02 (04.7) 041 (95.3) Assault 09 (04.5) 03 (33.3) 06 (66.7) Others 06 (03.0) 0 (0) 06 (100) * statistically significant in p<0.05: Chi-square test or t-test GCS: Glasgow coma scale, MVA: Motor vehicles accident
402 / 대한응급의학회지 : 제 20 권제 4 호 2009 Table 2. Details of patients with aneurysmal bleeding in traumatic SAH Mechanism GCS CT finding of SAH location clot &/or IPH thickness Fisher score IVH Hematoma Aneurysm site 01 MVA 15 sylvian - thick 3 - SDH ICA, MCA 02 MVA 15 sylvian - thick 3 - - ACA 03 MVA 03 diffuse basal + thick 4 all HC SCA 04 MVA 03 diffuse basal - thick 4 all - MCA, ICA 05 slip 10 diffuse basal + thick 4 - SDH MCA 06 assault 14 diffuse basal + thin 4 - IPH AcoA 07 MVA 11 diffuse basal - thick 4 LV, 4 V - MCA 08 MVA 13 sylvian - thin 2 - HC ICA, ACA 09 assault 15 sylvian + thin 4 - IPH MCA 10 MVA 08 sylvian - thick 3 - HC MCA 11 MVA 04 diffuse basal - thick 4 - SDH ICA 12 MVA 15 diffuse basal - thick 4 LV,4 V - AcoA 13 MVA 10 diffuse basal + thick 3 - IPH AcoA 14 slip 15 diffuse basal - thick 3 - - MCA 15 MVA 15 AI + thin 4 LV IPH ACA 16 MVA 06 AI + thin 4 - IPH ACA 17 MVA 14 diffuse basal + thick 4 all IPH Basilar 18 assault 03 diffuse basal - thick 4 4 V SDH MCA 19 MVA 15 sylvian - thin 2 - - PcoA 20 MVA 15 sylvian - thin 2 - - MCA 21 MVA 15 sylvian - thick 3 - SDH MCA GCS: Glasgow coma scale, CT: computed tomography, SAH: subarachnoid hemorrhage, IVH: intraventricular hemorrhage, IPH: intraparenchymal hemorrhage, MVA: Motor vehicles accident, AI: anterior interhemispheric, LV: lateral ventricle, 4V: fourth ventricle, ICA: internal carotid artery, ACA: anterior cerebral artery, ACoA: anterior communicating artery, MCA: middle cerebral artery, SCA: superior cerebellar artery, SDH: subdural hematoma, HC: hemorrhagic contusion A B Fig. 1. CT scan and CT angiogram of head. (A) CT scan revealing perimesencephalic hemorrhage, (B) CTA showing no abnormal findings such as aneurysms
박희정외 : 외상성두부손상에서기존뇌동맥류파열의 CT 소견 / 403 좌상및축외혈종의동반 (p=0.847, x 2 =0.037) 에서는유의한차이가없었다 (Table 4). 로지스틱회귀분석으로검정한결과출혈부위, 뇌동맥류호발부위에서의혈괴및뇌실질내출혈의소견으로뇌동맥류파열을예측할수있었으나, 출혈량, 뇌실내출혈, 혈성뇌좌상및축외혈종의소견으로는예측할수가없었다. 양측실비안열과전방대뇌반구열에확산된미만성기저수조의출혈, 한쪽실비안열에국한된출혈, 그리고전방대뇌반구열에국한된출혈인경우는그렇지않은경우보다뇌동맥류파열이 9,8배더많았고 (OR=9.884, p=0.034), 뇌동맥류호발부위에혈괴나뇌실질내출혈이동반된경우는그렇지않은경우보다 3.9배더많았다 (OR=3.954, p=0.024). 출혈부위 를제외시킨경우에는뇌동맥류호발부위에서의혈괴나뇌실질내출혈의동반, 다량의지주막하출혈이뇌동맥류의파열을암시하였고, 뇌실내출혈의동반, 혈성뇌좌상및축외혈종의동반은이를암시하지못하였다. 뇌동맥류호발부위에서의혈괴나뇌실질내출혈이동반된경우그렇지않은경우보다뇌동맥류파열이 5.69배더많았고 (OR=5.620, p=0.004), 한군데이상의지주막하공간에혈액이완전히찬경우는그렇지않은경우보다 3.5배더많았다 (OR=3.581, p=0.020). 뇌실내출혈이동반된경우는동반되지않은경우보다뇌동맥류가유의하게더많이발견되지않았고, 혈성뇌좌상이나축외혈종이동반된경우에도그렇지않은경우보다뇌동맥류가더많이발견되지않았다 (Table 5). A B Fig. 2. CT scan and CTA of head. (A) CT scan revealing basal cisternal hemorrhage, (B) CTA showing aneurysm of anterior communicating artery Table 3. Risk for aneurysmal bleeding according to location of traumatic SAH Variables Aneurysm (n=21) Non-aneurysm (n=179) p-value* x 2 -value Location of SAH Basal cisterns 21 (15.7) 113 (84.3) 0.000 11.557 Convexity only 0 (0) 066 (100) Blood in AI or sylvian fissures No 0 (0) 101 (100) 0.000 23.938 Yes 21 (21.2) 078 (78.8) CT distribution Hemispheric only (1) 0 (0) 066 (100) 0.002 12.448 Circle of Willis (2) 09 (19.1) 038 (80.9) 1+2 12 (13.8) 075 (86.2) * statistically significant in p<0.05: Chi-square test or Fisher s exact test TSAH: traumatic subarachnoid hemorrhage, SAH: subarachnoid hemorrhage, PM: perimesencephalic, AI: anterior interhemispheric, CT: computed tomography
404 / 대한응급의학회지 : 제 20 권제 4 호 2009 고 응급실에서비교적흔하게접하는외상성지주막하출혈 찰 의원인으로기존뇌동맥류의파열이종종보고되고있다. 뇌동맥류환자의과반수가재출혈로사망하는데재출혈은첫 24시간내에 4% 가발생하고, 첫 2주까지는하루에 1.5% 씩발생하여 2주말에가면 26.5% 에이른다 16,17). 두 Table 4. Risk factors for aneurysmal bleeding in SAH of basal cisterns Variables Aneurysm (n=21) Non-aneurysm (n=113) p-value* x 2 -value Location of basal cisterns SAH Diffuse basal cisterns 11 (35.5) 020 (64.5) 0.001 17.916 PM hemorrhage 0 (0) 039 (100) Unilateral Sylvian fissure 08 (17.8) 037 (82.2) Bilateral Sylvain fissure 0 (0) 07 (100) AI fissure 02 (16.7) 010 (83.3) Fisher CT score of SAH 2 03 (04.9) 058 (95.1) 0.002 12.650 3 07 (17.9) 032 (82.1) 4 11 (32.4) 023 (67.6) Thickness of SAH Thin SAH 07 (08.4) 076 (91.6) 0.003 08.645 Thick SAH 14 (27.5) 037 (72.5) Localized clot>3 5 mm or IPH No 13 (11.3) 102 (88.7) 0.001 11.705 Yes 08 (42.1) 011 (57.9) IVH No 14 (12.8) 095 (87.2) 0.060 03.535 Yes 07 (28.0) 018 (72.0) Extra-axial hematoma or hemorrhagic contusion No 12 (16.2) 062 (83.8) 0.847 00.037 Yes 09 (15.0) 051 (85.0) * statistically significant in p<0.05: Chi-square test or Fisher s exact test SAH : completely filling 1 cistern or fissure SAH: subarachnoid hemorrhage, PM: perimesencephalic, AI: anterior interhemispheric, CT: computed tomography, IVH: intraventricular hemorrhage, IPH: intraparenchymal hemorrhage Table 5. Independent prognostic factors for rupture of pre-existing aneurysms (n=134) Variables criteria p-value* OR CI Associated clot or IPH (+) vs (-) 0.024 3.954 1.1.97~13.063 Location of SAH 0.034 9.884.1.183~82.566 Amount of SAH thin vs thick 0.224 2.030 0.649~6.348. IVH (+) vs (-) 0.221 2.262 0.612~8.366. HC or extra-axial hematoma (+) vs (-) 0.623 0.758 0.252~2.284. (Exclusion of location of SAH) Associated clot or IPH (+) vs (-) 0.004 5.620.1.761~17.933 Amount of SAH thin vs thick 0.020 3.581.1.222~10.495 IVH (+) vs (-) 0.364 1.755 0.521~5.906. HC or extra-axial hematoma (+) vs (-) 0.822 0.884 0.301~2.592. * statistically significant in p<0.05: logistic regression analysis SAH: subarachnoid hemorrhage, CT: computed tomography, IVH: intraventricular hemorrhage, IPH: intraparenchymal hemorrhage, HC: hemorrhagic contusion
박희정외 : 외상성두부손상에서기존뇌동맥류파열의 CT 소견 / 405 부외상을당한경우대부분의환자들은응급실에서 CT검사를한다. 이때 CT에나타난출혈양상을가지고뇌동맥류파열을예측할수있다면뇌동맥류의조기치료가가능하여재출혈에의한사망을어느정도예방할수있으리라본다. 본연구결과에의하면외상성지주막하출혈에서 CT 에나타난출혈양상에따라뇌동맥류파열의예측이어느정도가능하였다. 특히출혈부위는 뇌동맥류군 과 비- 뇌동맥류군 을감별하는데에가장중요한소견이었다. 양측실비안열이나전방대뇌반구열에확산된기저수조의출혈과한쪽실비안열에국한된출혈, 전방대뇌반구열에국한된출혈은뇌동맥류파열을강력하게암시하는소견이므로응급실에서 CTA를시행하여뇌동맥류를발견하도록노력해야할것이다. 그러나중뇌주위에국한된출혈이나궁융부에국한된출혈에서는뇌동맥류가한례도발견되지않아이들환자에서의무분별한 CTA 시행은지양해야할것이다. 외상과뇌동맥류는첫째, 기존뇌동맥류의파열로외상을유발할수있고, 둘째, 외상으로기존뇌동맥류가파열될수있으며, 셋째, 파열되지않은뇌동맥류가두부외상을검사할때우연히발견되는등서로밀접한연관이있다 3). 비-뇌동맥류군 의지주막하출혈은주로뇌표면에있는동맥이나연결정맥이파열되어발생한다 18). 이경우본연구결과처럼출혈이주로궁륭부에국한되어있으며, 대부분혈관조영술이필요치않다 3). 이에반해 뇌동맥류군 의지주막하출혈은대부분기저수조에위치하고혈관조영술이절대적으로필요하다. 그러나일부에서는외상으로목이회전되면서과신전혹은굴곡될때기저-추골정맥이늘어나찢어지거나뇌기저부에있는뇌동맥들이외상으로손상되어다량의기저수조의출혈이발생할수있다고보고함으로써외상에의해서도다량의기저수조의출혈이발생할수있다는것을염두에두어야할것이다 19,20). 외상과뇌동맥류파열과의인과관계는이론의여지가있어외상성지주막하출혈이뇌동맥류의파열에의한것인지그렇지않은것인지의규명이쉽지않다 21). 그러나외상이기존뇌동맥류를파열시키는것은확실하며, 외상에의한기존뇌동맥류의파열빈도는 2.8~28% 로서매우다양하게보고되고있다 4). 두부외상을당하는경우에얇은뇌동맥류벽이전상상돌기 (anterior clinoid process) 나후상상돌기등과같은두개골융기에찔려파열되거나뇌앞부분의심한움직임으로대뇌겸앞부분이뇌동맥류에손상을주어뇌동맥류가파열된다 22,23). 또한외상을입을때발생하는가속력에의해동맥류의벽이견인되어파열되거나두부외상을입을때수축기혈압의상승으로동맥내압력 (endoluminal pressure) 이갑자기상승하여동맥류가파열된다 24). 본연구의결과처럼외상에의한뇌동맥류파열의경우자발성뇌동맥류파열과마찬가지로출혈이주로기저수조나 실비안열, 전방대뇌반구열에확산된다 3,25,26). Cummings 등 3) 은외상성지주막하출혈환자 60명중 5명에서뇌동맥류를발견하였는데이들모두출혈이기저수조나실비안열에확산되어있었다. 다른연구에서도뇌동맥류파열환자의 80% 는 CT에나타난출혈양상으로동맥류와그위치를예측할수있었고, 이러한예측은전뇌동맥, 전교통동맥, 중뇌동맥의동맥류인경우에만가능하였다 27). 뇌동맥류는내경동맥이나전뇌동맥, 중뇌동맥, 후뇌동맥, 추골-기저동맥의분지에잘발생하며, 동맥류가파열되면출혈은파열된뇌동맥류를중심으로하여그주위에확산되고, 그결과출혈은대부분윌리스환을중심으로주위에있는기저수조, 전방대뇌반구열, 실비안열에퍼지게된다 28). 뇌동맥류의호발부위주위에혈괴나뇌실질내출혈이동반되거나지주막하출혈의양이많으면뇌동맥류의파열과파열위치의예측이가능하다 26). 본연구의결과뇌동맥류호발부위에 3 5 mm 이상의혈괴가보이거나뇌실질내출혈이동반되면그렇지않은경우보다뇌동맥류의파열일가능성이 5.6배, 한군데이상의지주막하공간에혈액이완전히찬경우에는그렇지않은경우보다 3.5배가더높았다. 따라서기저수조, 실비안열, 전방대뇌반구열에출혈이있고, 혈괴및뇌실질내출혈이동반되고, 출혈량이많은경우에는출혈원인이뇌동맥류의파열임을강력하게예고한다고할수있다. 본연구에서기저수조의출혈이라하더라도전방대뇌반구열이나실비안열에확산되지않는중뇌주위출혈에서는뇌동맥류를발견할수없었다. 자발성지주막하출혈환자중혈관조영상음성인경우의 2/3는중뇌주위출혈환자이며, 중뇌주위에국한된출혈의원인이대부분정맥파열이기때문에혈관조영술이필요치않다고한다 29-31). 중뇌주위출혈은외상등에의해전다리뇌수조및다리사이수조 (interpeduncular cistern) 에있는모세혈관이나정맥들이파열되어발생하는데첫째, 로젠탈기저정맥 (basal vein of Rosenthal) 및그잔가지들이천막가장자리에서뒤틀리거나마찰되어발생하거나둘째, 외상에의한흉강내압상승으로내경동맥의환류가차단되고뇌압이상승하여전뇌교-중뇌정맥 (anterior pontomesencephalic vein), 각간정맥 (interpeduncular vein), 후교통정맥 (posterior communicating vein) 이갑작스럽게팽창하고파열되어발생한다 32,33). 그러나일부에서는중뇌주위출혈환자의 8.9% 에서뇌동맥류가발견되었고, 후방순환뇌동맥류환자의 16.6% 에서중뇌주위출혈양상을보였으며, 뇌동맥류파열인지아닌지를구별할수있는특정한 CT소견이없다고보고하면서중뇌주위출혈의소견을보이면반드시혈관조영상이필요하다고하였다 34). 안장위수조 (suprasellar cistern) 를포함하지않은양측실비안열의출혈은한쪽실비안열에국한된출혈과달리뇌동맥류를발견할수가없었다. 실비안열의출혈은주로
406 / 대한응급의학회지 : 제 20 권제 4 호 2009 중뇌동맥류파열을예측하는데이경우출혈이실비안열에서시작하여윌리스환의중심부를향하여확산된다 26). 뇌동맥류파열에서출혈의확산경로를고려할때한쪽실비안열의출혈이안장위수조를통과하지않고반대측실비안열에확산될수는없다. 따라서안장위수조에확산되지않은양측실비안열의출혈은뇌동맥류파열보다실비안열근처의뇌조직이국소적으로손상되어주위혈관이파열되었거나측두엽앞부분이좌상으로중뇌동맥의측두및두정분지들이손상되어발생한것이라할수있다 31,35). 외상성지주막하출혈은기저수조에흔치않으나이경우뇌좌상이나뇌경막하출혈과깊은연관성이있는것으로알려져있다 36). 따라서뇌좌상및뇌경막하출혈의동반은뇌동맥류파열보다주로외상성지주막하출혈을생각할수있다. 그러나본연구에서는뇌동맥류파열에의한지주막하출혈환자의 15% 에서도이들병변이동반된것으로나타나뇌좌상이나뇌경막하출혈이동반되어있지만출혈이기저수조에확산되어있는경우뇌동맥류파열의가능성이있기때문에반드시 CTA를시행하여야할것이다. 본연구의제한점으로는첫째, 후향적연구라는점이다, 후향적인연구는자료대부분을의무기록에의존해야하기때문에의무기록의충실성에따라결과가달라질수있다. 그러나본연구가후향적인연구이지만조사항목이대부분 CT소견들이라주관이많이개재되지않은객관적인요소들이많아자료의편견에큰문제가없을것으로생각한다. 둘째, 연구대상자수가적다는것이다. 6년간의자료이지만대상환자 200명중뇌동맥류의발견이 21명에불과하다. 따라서하나의뇌동맥류가추가되어도결론이다른방향으로날수있다는문제점이있다. 셋째, 본연구에서동맥류를낭상동맥류로한정하였고, 잠재성동맥류 (occult aneurysm) 나속립동맥류 (miliary aneurysm) 를고려하지않았다는점이다. 외상성지주막하출혈에서도출혈이기저수조, 전방대뇌반구열, 실비안열에확산되어있으면뇌동맥류파열일가능성을항상고려해야되겠지만뇌동맥류를발견할수없는경우가많았고, 특히혈괴및뇌실질내출혈이동반되고, 지주막하출혈의출혈량이많은경우에도상당수뇌동맥류를발견할수없었다. 즉, CT의출혈양상으로는뇌동맥류가충분히예상됨에도불구하고뇌동맥류가발견되지않는것이다. 이경우상당수에서는 CTA에발견되지않는잠재성동맥류나속립동맥류를고려해야할것이다 23). 이들뇌동맥류는큰뇌동맥의분지에호발하는낭상동맥류와달리동맥의주줄기에서발생하며, 동맥류의최대직경과높이가모동맥 (parent artery) 의직경보다작다. 따라서 CTA나 DSA에서속립동맥류와작은동맥의고리 (loop) 및모퉁이 (angle) 의감별이어려워잘발견되지않는다 37). 뇌동맥류의크기가 5 mm 이상이면 CTA의민감도가 95% 정도되지만 2 mm 미만이면 50% 이하로떨어진다 38). 또한 CTA는두개골, 특히전상상돌기부군에있는동 맥에서는정확도가급속하게떨어진다 39). 결 외상성지주막하출혈환자에서 10.5% 의비교적높은비율로뇌동맥류파열이발견되기때문에외상성지주막하출혈에서도자발성지주막하출혈과마찬가지로 CTA를시행하여뇌동맥류파열을감별해야한다. 특히기저수조의출혈로서실비안열이나전방대뇌반구열에확산되고, 뇌동맥류호발부위에혈괴및뇌실질내출혈이동반되거나지주막하출혈의양이많은경우기존뇌동맥류의파열에의한지주막하출혈일가능성이높기때문에응급실에서 CTA검사를반드시시행해야한다. 본연구는다년간에걸쳐조사한연구이지만하나의응급의료센터의자료에불과하기때문에결론을내리는데다소간의편견이있을수있다. 향후더많은병원이참여하여대단위연구가있어야할것으로생각한다. 또한잠재성동맥류나속립동맥류가파열될경우에도 CT에서낭상동맥류와비슷한출혈양상을보이기때문에이들을발견하는데민감도가높은진단기기의개발이뒤따라야할것이다. 론 참고문헌 01. Cairns CJ, Finfer SR, Harrington TJ, Cook R. Papaverine angioplasty to treat cerebral vasospasm following traumatic subarachnoid haemorrhage. Anaesth Intensive Care 2003;31:87-91. 02. Mattioli C, Beretta L, Gerevini S, Veglia F, Citerio G, Cormio M, et al. Traumatic subarachnoid hemorrhage on the computerized tomography scan obtained at admission: a multicenter assessment of the accuracy of the diagnosis and the potential impact on patient outcome. J Neurosurg 2003;98:37-42. 03. Cummings TJ, Johnson RR, Diaz FG, Michael DB. The relationship of blunt head trauma, subarachnoid hemorrhage, and rupture of pre-existing intracranial saccular aneurysms. Neurol Res 2000;22:165-70. 04. Senegor M. Traumatic pericallosal aneurysm in a patient with no major trauma. Case report. J Neurosurg 1991; 75:475-7. 05. Hop JW, Rinkel GJ, Algra A, van Gijn J. Case-fatality rates and functional outcome after subarachnoid hemorrhage: a systematic review. Stroke 1997;28:660-4. 06. Kaufmann TJ, Huston J 3rd, Mandrekar JN, Schleck CD, Thielen KR, Kallmes DF. Complications of diagnostic cerebral angiography: evaluation of 19,826 consecutive patients. Radiology 2007;243: 812-9.
박희정외 : 외상성두부손상에서기존뇌동맥류파열의 CT 소견 / 407 07. El Khaldi M, Pernter P, Ferro F, Alfieri A, Decaminada N, Naibo L, et al. Detection of cerebral aneurysms in nontraumatic subarachnoid haemorrhage: role of multislice CT angiography in 130 consecutive patients. Radiol Med 2007;112:123-37. 08. Romijn M, Gratama van Andel HA, van Walderveen MA, Sprengers ME, van Rijn JC, van Rooij WJ, et al. Diagnostic accuracy of CT angiography with matched mask bone elimination for detection of intracranial aneurysms: comparison with digital subtraction angiography and 3D rotational angiography. AJNR Am J Neuroradiol 2008;29:134-9. 09. Chen W, Yang Y, Xing W, Qiu J, Peng Y. Sixteen-row multislice computed tomography angiography in the diagnosis and characterization of intracranial aneurysms: comparison with conventional angiography and intraoperative findings. J Neurosurg 2008;108:1184-91. 10. Chang LK, Liew NS, Soh HL, Tan SZ, Wong SH. Clinical utility of 64-row multislice CT angiography in the detection of cerebral aneurysms in acute subarachnoid hemorrhage. Med J Malaysia 2008;63:131-6. 11. Agid R, Willinsky RA, Farb RI, Terbrugge KG. Life at the end of the tunnel: why emergent CT angiography should be done for patients with acute subarachnoid hemorrhage. AJNR Am J Neuroradiol 2008;29:e45-7. 12. Hino A, Fujimoto M, Iwamoto Y, Yamaki T, Katsumori T. False localization of rupture site in patients with multiple cerebral aneurysms and subaracnoid hemorrhage. Neurosurgery 2000;46: 825-830. 13. Nehls DG, Flom RA, Carter LP, Spetzler RF. Multiple intracranial aneurysms: determining the site of rupture. J Neurosurg 1985;63:342-8. 14. Edlow JA. Diagnosis of subarachnoid hemorrhage. Neurocrit Care 2005;2:99-109. 15. Fisher CM, Kistler JP, Davis JM. Relation of cerebral vasospasm to subarachnoid hemorrhage visualized by computerized tomographic scanning. Neurosurgery 1980;6:1-9. 16. Broderick JP, Brott TG, Duldner JE, Tomsick T, Leach A. Initial and recurrent bleeding are the major causes of death following subarachnoid hemorrhage. Stroke 1994;25: 1342-7. 17. Roos YB, de Haan RJ, Beenen LF, Groen RJ, Albrecht KW, Vermeulen M. Complications and outcome in patients with aneurysmal subarachnoid haemorrhage: a prospective hospital based cohort study in the Netherlands. J Neurol Neurosurg Psychiatry 2000;68:337-41. 18. Kakarieka A. Review on traumatic subarachnoid hemorrhage. Neurol Res 1997;19:230-2. 19. Plant JR, Butt JC. Laceration of vertebral artery. an historic boxing death. Am J Forensic Med Pathol 1993;14:61-4. 20. Ehrlich E, Farr T, Maxeiner H. Detection of arterial bleeding points in basilar subarachnoid hemorrhage by postmortem angiography. Leg Med (Tokyo) 2008;10:171-6. 21. Freytag E. Fatal rupture of intracranial aneurysms. survey of 250 medicolegal cases. Arch Pathol 1966;81:418-24. 22. Newbarr FD, Courville CB. Trauma as the possible significant factor in the rupture of congenital intracranial aneurysms. J Forensic Sci 1958;3:174-97. 23. Amagasa M, Onuma T, Suzuki J, Fujimoto S, Sakurai Y. Traumatic anterior cerebral artery aneurysms-experiences in 4 cases and review of the literature. No Shinkei Geka 1986;14:1585-92. 24. Ross IB, Fratkin JD. Cerebral saccular aneurysm rupture after head injury. J Trauma 2007;63:e47-50. 25. Hsieh CT, Lin EY, Tsai TH, Chiang YH, Ju DT. Delayed rupture of pre-existing cerebral aneurysm in a young patient with minor head trauma. J Clin Neurosci 2007;14: 1120-2. 26. Karttunen AI, Jartti PH, Ukkola VA, Sajanti J, Haapea M. Value of the quantity and distribution of subarachnoid haemorrhage on CT in the localization of a ruptured cerebral aneurysm. Acta Neurochir (wien) 2003;145:655-61. 27. Hillman J. Selective angiography for early aneurysm detection in acute subarachnoid haemorrhage. Acta Neurochir (Wien);1993:121: 20-5. 28. Rinkel GJ, Djibuti M, Algra A, van Gijn J. Prevalence and risk of rupture of intracranial aneurysms: a systematic review. Stroke 1998;29:251-6. 29. Hui FK, Tumialán LM, Tanaka T, Cawley CM, Zhang YJ. Clinical differences between angiographically negative, diffuse subarachnoid hemorrhage and perimesencephalic subarachnoid hemorrhage. Neurocrit Care 2009;11:64-70. 30. Kang DH, Park J, Lee SH, Park SH, Kim YS, Hamm IS. Does non-perimesencephalic type non-aneurysmal subarachnoid hemorrhage have a benign prognosis? J Clin Neurosci 2009;16:904-8. 31. Rinkel GJ, van Gijn J, Wijdicks EF. Subarachnoid hemorrhage without detectable aneurysm. A review of the causes. Stroke 1993;24:1403-9. 32. Rinkel GJ, Wijdicks EF, Vermeulen M, Ramas LM, Tanghe HL, Hasan D, et al. Nonaneurysmal perimesencephalic subarachnoid hemorrhage: CT and MR patterns that differ from aneurysmal rupture. AJNR Am J Neuroradiol 1991;12:829-34. 33. Watanabe A, Hirano K, Kamada M, Imamura K, Ishii N, Sekihara Y, et al. Perimesencephalic nonaneurysmal subarachnoid haemorrhage and variations in the veins. Neuroradiology 2002;44:319-25. 34. Alén JF, Lagares A, Lobato RD, Gómez PA, Rivas JJ,
408 / 대한응급의학회지 : 제 20 권제 4 호 2009 Ramos A. Comparison between perimesencephalic nonaneurysmal subarachnoid hemorrhage and subarachnoid hemorrhage caused by posterior circulation aneurysms. J Neurosurg 2003;98:529-35. 35. Shigemori M, Tokutomi T, Hirohata M, Maruiwa H, Kaku N, Kuramoto S. Clinical significance of traumatic subarachnoid hemorrhage. Neurol Med Chir (Tokyo) 1990;30:396-400. 36. Kakarieka A, Braakman R, Schakel EH. Clinical significance of the finding of subarachnoid blood on CT scan after head injury. Acta Neurochir (Wien) 1994;129:1-5. 37. Miyazaki Y, Ando E. On the miliary intracranial aneurysm-its significance in subarachnoid hemorrhage author s thansl. No Shinkei Geka 1976;4:853-60. 38. Wintermark M, Uske A, Chalaron M, Regli L, Maeder P, Meuli R, et al. Multislice computerized tomography angiography in the evaluation of intracranial aneurysms: A comparison with intraarterial digital subtraction angiography. J Neurosurg 2003;98:828-36. 39. Livingston RR. Regarding the risk of death from CT angiography in patients with subarachnoid hemorrhage. AJNR Am J Neuroradiol 2008;29:e44.