Neurol Med Chir (Tokyo) 42, 250¿254, 2002 Anterior Cerebral Artery Dissections Manifesting as Cerebral Hemorrhage and Infarction, and Presenting as Dynamic Angiographical Changes —Case Report— Shigeyuki SAKAMOTO, Tetsuji INAGAWA, Fusao IKAWA, Hitoshi KAWAMOTO, and Naohiko OHBAYASHI Department of Neurosurgery, Shimane Prefectural Central Hospital, Izumo, Shimane Abstract A 65-year-old woman presented with multiple dissecting aneurysms of the anterior cerebral artery (ACA) manifesting as hemiparesis on the right with dominance in the lower extremity. Computed tomography revealed hematoma in the left frontal lobe, corresponding to the area perfused by the callosomarginal artery. Initial angiography showed string sign and occlusion in the distal portion of the left callosomarginal artery and abnormal feeding suggesting double lumen of the A2 portion of the left ACA. The patient was treated conservatively under a diagnosis of multiple spontaneous dissecting aneurysms of the left ACA. Repeat angiography on Day 8 showed improvement of the string sign and occlusion in the left callosomarginal artery, and change of the double lumen of the A2 portion into string sign. Further angiography on Day 36 showed normalization of the left callosomarginal artery and improvement of the string sign in the A2 portion. Multiple spontaneous dissecting aneurysms of the ACA are extremely rare. Serial angiography beginning in the early stage will be important for correct diagnosis. Key words: anterior cerebral artery, spontaneous dissecting aneurysm cerebral hemorrhage, cerebral infarction, multiple lesions, Introduction Case Report Dissecting aneurysms are now recognized as a cause of hemorrhagic or ischemic stroke. Dissecting aneurysms occur most frequently in the vertebrobasilar arteries (VBAs),36) and are relatively rare in the anterior circulation, especially in the anterior cerebral artery (ACA).1,4–10,12,14–18,20,21,23,25, 26,29,30,32,33,37,38) Spontaneous intracranial dissecting aneurysms usually develop as a single lesion,34,36) whereas multiple spontaneous dissecting aneurysms of the ACA have not been reported. We describe a case of multiple spontaneous dissecting aneurysms of the ACA. A 65-year-old hypertensive woman was admitted with disturbance of consciousness and right-sided hemiparesis without obvious evidence of trauma on May 9, 1996. She did not habitually smoke or drink. On admission, her Glasgow Coma Scale score was 14. She had hemiparesis on the right with dominance in the lower extremity. Hematological and laboratory examinations found no abnormality. Computed tomography (CT) on Day 0 revealed hematoma in the left frontal lobe (Fig. 1). Angiography on Day 1 showed string sign and occlusion in the distal part of the left callosomarginal artery, and abnormal feeding suggesting double lumen of the A2 portion of the left ACA (Fig. 2). An- Received June 14, 2001; Accepted April 23, 2002 Author's present address: S. Sakamoto, M.D., Department of Neurosurgery, Hiroshima University School of Medicine, Hiroshima, Japan. 250 ACA Dissections Fig. 1 Computed tomography scans on admission showing high-density lesions in the left frontal lobe and the left lateral ventricle. Fig. 3 251 Computed tomography scans on Day 3 showing a low-density lesion in the left frontal lobe (arrows). comatose on Day 3. CT showed a low-density area in the left frontal region (Fig. 3). Repeat angiography on Day 8 showed improvement of the stenosis and occlusion of the left callosomarginal artery, and change of the double lumen of the A2 portion of the left ACA into string sign with stenosis of approximately 50% and a length of 1.5 cm (Fig. 4). Third angiography on Day 36 showed normalization of the left callosomarginal artery and improvement of the stenosis in the A2 portion (Fig. 5). At 6 months after onset, she was transferred to another hospital with moderate disability. Discussion Fig. 2 Left carotid angiogram on Day 1, arterial phase, lateral view, showing stenosis of approximately 20% with a length of 7 mm and occlusion in the distal part of the left callosomarginal artery (arrows), and abnormal feeding suggesting double lumen of the A2 portion (arrowheads). giography found no abnormality in the other vessels, including the proximal portion of the left callosomarginal artery. The patient was treated conservatively under a diagnosis of multiple dissecting aneurysms of the left ACA. She became semi- Neurol Med Chir (Tokyo) 42, June, 2002 Multiple intracranial dissecting aneurysms are very rare. A nationwide study of 357 patients with intracranial arterial dissection found that 35 (10%) had multiple lesions: 15 (43%) had onset of hemorrhagic stroke and 20 (57%) had onset of ischemic stroke.36) In another study of 260 patients with intracranial arterial dissection, 27 (10%) had multiple lesions: 21 (78%) were located in the bilateral VBAs, three (11%) in the unilateral anterior circulation and VBA, and three (11%) in the bilateral anterior circulations.34) However, neither study discussed multiple lesions. We found 13 cases of multiple intracranial dissecting aneurysms, 12 located in the bilateral VBAs2,3,13,22,24,27,35) and one in the anterior choroidal artery and basilar artery.2) On the other hand, only 36 reported cases of spontaneous dissecting aneurysms of the ACA have been reported: 11 with hemorrhage,4–6,16,18,29,33,37) 21 with infarction,1,8,9,12, 15,18,20,21,23,25,26,29,30,32) and four with both hemorrhage and infarction.7,10,38) However, multiple dissecting 252 Fig. 4 S. Sakamoto et al. Repeat left carotid angiogram on Day 8, arterial phase, lateral view, showing improvement of the string sign and occlusion of the left callosomarginal artery (arrows). The double lumen of the A2 portion of the anterior cerebral artery, observed in the first angiogram, has changed into string sign with stenosis of approximately 50% and a length of 1.5 cm (arrowheads). aneurysms of the ACA have not been reported. In addition, the natural history of multiple intracranial dissecting aneurysms has not been elucidated because of the small number of patients with such lesions and the difficulty in detection. The association between the mechanism of dissection of the arterial wall and clinical onset may involve: Dissection between the internal elastic lamina and the media (subintimal dissection) resulting in ischemic onset through stenosis or occlusion of the dissecting lesion by hemodynamic mechanism; dissection between the media and the adventitia (subadventitial dissection) resulting in hemorrhagic onset; or both of these.39) Pearl and string, double lumen, irregular dilatation, and string and occlusion signs are well known angiographical indicators of dissecting aneurysms. There are no obvious differences in these findings between patients with hemorrhagic onset and those with ischemic onset.11,19,25,28,31,40) These signs often change and sometimes improve due to absorption of hemorrhage into the arterial wall and/or thrombolysis of the thrombus.11,19,25,28,31,40) During the course of Fig. 5 Left carotid angiogram on Day 36, arterial phase, lateral view, showing normalization of the left callosomarginal artery and improvement (arrowheads) of the string sign in the A2 portion. thrombolysis, it is possible that a part of the thrombus can cause remote embolism,11,28,32) and in such a case, angiography may show double lesions. In this case, we speculated that the double lesions were due to multiple dissecting aneurysms, and not due to remote embolism, because of the following reasons. First, cerebral hemorrhage and infarction on CT corresponded to the area perfused by the callosomarginal artery. Second, the changes of angiographic findings of the A2 trunk and the distal portion of the callosomarginal artery were demonstrated by serial angiography, whereas the proximal portion of the callosomarginal artery was always normal. Third, embolus from the dissecting part of the A2 trunk is more likely to occlude the pericallosal artery than the callosomarginal artery. The difficulty in detecting dissecting aneurysms of the ACA, including multiple lesions, may be due to the time lag between CT and angiography, especially at the onset of ischemic stroke. Cerebral infarction due to dissecting aneurysms of the ACA was observed on CT from 1 to 8 days after onset (mean 2.2 days), whereas the initial angiography was performed from 0 to 38 days (mean 6.8 days).1,6,8–10,15,23,26,30,32,38) Therefore, specific angiographical findings of dissecting aneurysms may already have changed during the in- Neurol Med Chir (Tokyo) 42, June, 2002 ACA Dissections tervening period. Dissecting aneurysms of the ACA are very rare, so serial angiography beginning in the early stage will be important to detect multiple dissecting aneurysms. 14) 15) References 1) 2) 3) 4) 5) 6) 7) 8) 9) 10) 11) 12) 13) Araki T, Ouchi M, Ikeda Y: [A case of anterior cerebral artery dissecting aneurysm]. No Shinkei Geka 24: 87–91, 1996 (Jpn, with Eng abstract) Berger MS, Wilson CB: Intracranial dissecting aneurysms of the posterior circulation. J Neurosurg 61: 882–894, 1984 Friedman AH, Drake CG: Subarachnoid hemorrhage from intracranial dissecting aneurysm. J Neurosurg 60: 325–334, 1984 Guridi J, Gallego J, Monzon F, Aguilera F: Intracerebral hemorrhage caused by transmural dissection of the anterior cerebral artery. Stroke 24: 1400–1402, 1993 Hashimoto H, Iida J, Shin Y, Hironaka Y, Sakaki T: Subarachnoid hemorrhage from intracranial dissecting aneurysms of the anterior circulation: Two case reports. Neurol Med Chir (Tokyo) 39: 442–446, 1999 Hayashi N, Fukuda O, Endo S, Takaku A: [Intracerebral hemorrhage secondary to dissecting aneurysm of the anterior cerebral artery]. No To Shinkei 48: 1053–1056, 1996 (Jpn, with Eng abstract) Honda N, Yuge T, Miyagi J, Shigemori M: [A surgical case of dissecting aneurysm of the anterior cerebral artery]. No Shinkei Geka Journal 6: 634–638, 1997 (Jpn, with Eng abstract) Ishikawa R, Sunagawa S, Itoh I, Iwashita K: [An experience of dissecting cerebral aneurysm of the anterior cerebral artery]. No Shinkei Geka 21: 355–359, 1993 (Jpn, with Eng abstract) Kanai H, Koide K, Niwa Y, Umezu M: [Spontaneous dissection of the A2 segment of the anterior cerebral artery presenting cerebral infarction: A case report]. No Shinkei Geka Journal 8: 732–737, 1999 (Jpn, with Eng abstract) Kato N, Yamada Y, Hyodo A, Nose T: [A case of anterior cerebral artery dissection presenting subarachnoid hemorrhage and cerebral infarction]. No Shinkei Geka Journal 9: 157–161, 2000 (Jpn, with Eng abstract) Kawaguchi T, Asada M, Nagao T, Tamaki N, Matsumoto S: [Spontaneous dissecting aneurysm of the cervical internal carotid artery: Report of 2 cases and review of literature]. No Shinkei Geka 12: 1395–1400, 1984 (Jpn, with Eng abstract) Kidooka M, Okada T, Sonobe M, Nakagawa T, Handa J: Dissecting aneurysm of the anterior cerebral artery: Report of two cases. Surg Neurol 39: 53–57, 1993 Kitanaka C, Sasaki T, Eguchi T, Teraoka A, Nakane M, Hoya K: Intracranial vertebral artery dissections: Clinical, radiological features, and surgical considerations. Neurosurgery 34: 620–627, 1994 Neurol Med Chir (Tokyo) 42, June, 2002 16) 17) 18) 19) 20) 21) 22) 23) 24) 25) 26) 253 Komiyama M, Morikawa T, Nakajima H, Nishikawa M, Yasui T: Embolic cerebellar infarction caused by spontaneous dissection of the extracranial vertebral artery. Neurol Med Chir (Tokyo) 40: 310–314, 2000 Koyama S, Kotani A, Sasaki J: Spontaneous dissecting aneurysm of the anterior cerebral artery: Report of two cases. Surg Neurol 46: 55–61, 1996 Lanzino G, Kaptain G, Kallmes DF, Dix JE, Kassell NF: Intracranial dissecting aneurysm causing subarachnoid hemorrhage: The role of computerized tomographic angiography and magnetic resonance angiography. Surg Neurol 48: 477–481, 1997 Matsumoto T, Yamaura I, Tani E, Fukushima Y, Natsume S: [A case of anterior cerebral artery dissecting aneurysm presenting subarachnoid hemorrhage]. Surgery for Cerebral Stroke 25: 472–475, 1997 (Jpn, with Eng abstract) Nagata K, Sato K: [Surgical treatment for the dissecting aneurysm of the anterior cerebral artery]. Surgery for Cerebral Stroke 24: 80–84, 1996 (Jpn, with Eng abstract) Nakagawa K, Touho H, Morisako T, Osaka Y, Tatsuzawa K, Nakae H, Owada K, Matsuda K, Karasawa J: Long-term follow-up study of unruptured vertebral artery dissection: Clinical outcomes and serial angiographic findings. J Neurosurg 93: 19–25, 2000 Nakazawa T, Saito A, Watanabe K, Matsuda M, Handa J: [Dissecting aneurysm of the anterior cerebral artery: Report of a case]. No Shinkei Geka 12: 1211–1216, 1984 (Jpn, with Eng abstract) Nomura H, Nishijima M, Hounoki S, Oka N, Takaku A: [A dissecting aneurysm of the anterior cerebral artery: A case report and review of the literature]. No Shinkei Geka Journal 2: 152–156, 1993 (Jpn, with Eng abstract) Okamura K, Watanabe M, Nakamura S, Yamamoto M, Fukui K: [Intracranial dissecting aneurysms of the posterior circulation: Report of six cases and review of literature]. No Socchu 12: 369–380, 1990 (Jpn, with Eng abstract) Okuno S, Ochiai C, Nagai M: Dissecting aneurysm of the anterior cerebral artery causing hemorrhagic infarction. Surg Neurol 45: 25–30, 1996 Ono J, Yamaura A, Kobayashi S, Kubota M, Miyata A: [Management of unruptured intracranial dissecting aneurysms in vertebrobasilar system: Analysis of serial changes in angiographic findings and longterm outcome]. Surgery for Cerebral Stroke 23: 167–172, 1995 (Jpn, with Eng abstract) Sakamoto S, Inagawa T, Ikawa F, Kawamoto H, Ohbayashi N, Sakoda E, Hidaka T: [Dissecting aneurysm of the anterior cerebral artery with persistent pearl & string sign on cerebral angiograms over a period of eight years]. No Shinkei Geka 29: 1093–1098, 2001 (Jpn, with Eng abstract) Sasaki O, Koike T, Takeuchi S, Tanaka R: Serial angiography in a spontaneous dissecting anterior cerebral artery aneurysm. Surg Neurol 36: 49–53, 254 27) 28) 29) 30) 31) 32) 33) 34) S. Sakamoto et al. 1991 Sasayama T, Korosue K: [Spontaneous resolution of the unruptured dissecting aneurysms of bilateral vertebral arteries with conservative treatment: Analysis of the transient enlargement of aneurysmal dilatation]. No Shinkei Geka 28: 47–51, 2000 (Jpn, with Eng abstract) Srinivasan J, Newell DW, Sturzenegger M, Mayberg MR, Winn HR: Transcranial Doppler in the evaluation of internal carotid artery dissection. Stroke 27: 1226–1230, 1996 Tanigawa R, Anei R, Izumi N, Hashizume A, Fujita T, Hashimoto M, Kamiyama H: [Strategy of treatment for anterior cerebral artery dissection]. Surgery for Cerebral Stroke 27: 433–438, 1999 (Jpn, with Eng abstract) Terai S, Matsubara T: [A case of dissecting aneurysm involving solely anterior cerebral artery]. No Socchu 13: 159–164, 1991 (Jpn, with Eng abstract) Uno M, Ueda S, Shinno K, Nishitani K: [Management and long-term follow-up results in patients with carotid artery dissection]. No Shinkei Geka 25: 417–423, 1997 (Jpn, with Eng abstract) Yamaguchi S, Oki S, Mikami T, Kawamoto Y, Ito Y, Kuwamoto K: [A case of an intracranial dissecting aneurysm localized in the anterior cerebral artery]. No Shinkei Geka Journal 7: 230–234, 1998 (Jpn, with Eng abstract) Yamamoto H, Fukuda O, Saito T, Endo S, Takaku A: [A subarachnoid hemorrhage secondary to a dissecting aneurysm of the anterior cerebral artery: A case report]. No Shinkei Geka Journal 7: 310–314, 1998 (Jpn, with Eng abstract) Yamaura A, Ono J, Okimura Y, Fukuda K, Miyata A: [Analysis of nontraumatic intracranial arterial dis- 35) 36) 37) 38) 39) 40) sections: Carotid lesion vs. vertebrobasilar lesion]. Surgery for Cerebral Stroke 21: 341–346, 1993 (Jpn, with Eng abstract) Yamaura A, Watanabe Y, Saeki N: Dissecting aneurysms of the intracranial vertebral artery. J Neurosurg 72: 183–188, 1990 Yamaura A, Yoshimoto T, Hashimoto N, Ono J: [Nationwide study of nontraumatic intracranial arterial dissection: Clinical features and outcome]. Surgery for Cerebral Stroke 26: 79–86, 1998 (Jpn, with Eng abstract) Yano H, Sawada M, Shinoda J, Funakoshi T: Ruptured dissecting aneurysm of the peripheral anterior cerebral artery: Case report. Neurol Med Chir (Tokyo) 35: 450–453, 1995 Yasukawa K, Kamijo Y, Momose G, Kobayashi S, Ikeda A: [A case of anterior cerebral artery dissecting aneurysm presenting subarachnoid hemorrhage and cerebral infarction at the same time]. Surgery for Cerebral Stroke 21: 461–466, 1993 (Jpn, with Eng abstract) Yonas H, Agamanolis D, Takaoka Y, White RJ: Dissecting intracranial aneurysms. Surg Neurol 8: 407–415, 1977 Yoshimoto Y, Wakai S: Unruptured intracranial vertebral artery dissection: Clinical course and serial radiographic imagings. Stroke 28: 370–374, 1997 Address reprint requests to: S. Sakamoto, M.D., Department of Neurosurgery, Hiroshima University School of Medicine, 1–2–3 Kasumi, Minami–ku, Hiroshima 734–8551, Japan. e-mail: sakamoto@hiroshima-u.ac.jp. Neurol Med Chir (Tokyo) 42, June, 2002