Clinical Neurology and Neurosurgery 120 (2014) 113–115
Contents lists available at ScienceDirect
Clinical Neurology and Neurosurgery journal homepage: www.elsevier.com/locate/clineuro
Case report
Concurrent unilateral moyamoya disease and vertebrobasilar junction aneurysm associated with fenestration – Case report and management Shigeo Ohba a,b,∗ , Syunsuke Shibao b , Hideyuki Tomita b , Toru Nakagawa b , Kazunori Akaji c , Hideki Murakami b a
Department of Neurosurgery, Keio University School of Medicine, Tokyo, Japan Department of Neurosurgery, Ashikaga Red Cross Hospital, Ashikaga, Tochigi, Japan c Department of Neurosurgery, Mihara Memorial Hospital, Ohtamachi, Isesaki, Gunma, Japan b
a r t i c l e
i n f o
Article history: Received 2 September 2013 Received in revised form 26 February 2014 Accepted 5 March 2014 Available online 13 March 2014 Keywords: Moyamoya disease Vertebral aneurysm Fenestration STA-MCA bypass
1. Introduction The incidence of fenestration of the basilar artery has been reported to be 1.3–6% in autopsy series and less than 1% in angiographic series [1]. Similar to that noted in arterial bifurcations, fenestrations also have a tendency to develop aneurysms [1]. The incidence of aneurysms is reported to be 7% with basilar fenestrations, and the incidence of fenestrations with vertebrobasilar junction aneurysm is reported to be 35.5% [2]. Intracranial aneurysms are occasionally accompanied by moyamoya disease. These aneurysms are generally classified into 3 subtypes: aneurysms at major arteries, aneurysms at distal peripheral arteries, and aneurysms of moyamoya vessels [3]. Aneurysms at major arteries are likely to occur in the posterior circulation. The gradual reduction of the perfusion in the anterior circulation due to chronic stenosis and occlusion of the internal carotid artery (ICA) increase the hemodynamic stress in the posterior circulation, which may contribute to the development of aneurysms [4].
∗ Corresponding author at: Department of Neurosurgery, Keio University School of Medicine, 35 Shinano-machi, Shinjuku-ku, Tokyo 160-8582, Japan. Tel.: +81 3 5363 3808; fax: +81 3 3354 8053. E-mail address: [email protected] (S. Ohba). http://dx.doi.org/10.1016/j.clineuro.2014.03.003 0303-8467/© 2014 Elsevier B.V. All rights reserved.
In the present report, I describe a case of concurrent moyamoya disease and vertebrobasilar aneurysm that were consecutively treated. 2. Case report A 58-year-old woman presented to our hospital with headache and severe left hemiparesis. She did not have a history of hypertension, and was not receiving antiplatelet nor anticoagulant treatment. Computed tomography (CT) scans indicated right putaminal hemorrhage with intraventricular hemorrhage (Fig. 1A). Magnetic resonance angiography could not clearly indicate the right middle cerebral artery (MCA) and right anterior cerebral artery (ACA), but showed an aneurysm at the vertebral artery. Angiograms indicated stenosis of the terminal position of the right ICA, and the proximal position of the right MCA and ACA with moyamoya vessels, as well as an aneurysm at the vertebrobasilar junction. Moreover, we found that the right posterior cerebral artery (PCA) filled the right hemisphere (Fig. 1B–D). Threedimensional CT angiography revealed that the aneurysm, 7 mm in size, was located at the proximal position of the fenestration (Fig. 1E). Due to arterial changes in the anterior circulation, there appeared to be a hemodynamic burden on the vertebral artery (VA). Although the aneurysm had not ruptured, treatment of the aneurysm was essential, considering the size of the aneurysm and the hemodynamic stress. Therefore, the patient underwent
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S. Ohba et al. / Clinical Neurology and Neurosurgery 120 (2014) 113–115
Fig. 1. Computed tomography scans on admission revealing right putaminal hemorrhage with intraventricular hemorrhage (A). A right internal carotid artery (ICA) angiogram demonstrating the stenosis of the terminal position of the right ICA, and the proximal position of the right middle cerebral artery and anterior cerebral artery with moyamoya vessels (B). Left vertebral artery angiogram indicating an aneurysm at the vertebrobasilar junction (C). Left vertebral artery angiogram showing that the right hemisphere was filled by the right posterior cerebral artery (D). Three-dimensional computed tomography angiography indicating that the aneurysm is located at the proximal end of the fenestration (E).
right superficial temporal artery (STA)-MCA bypass 2 months after admission. The postoperative course was uneventful, and a right external carotid artery angiogram showed that the right cerebral hemisphere was perfused via the right STA. Two months after the surgery, the patient was referred to another hospital where an endovascular procedure was performed for the aneurysm. The aneurysm was completely occluded by using Guglielmi detachable coils (Fig. 2). The patient’s postoperative course was uneventful. 3. Discussion The basilar artery is formed by the fusion of the bilateral longitudinal neural arteries during the fifth gestational week. During this process, temporary bridging arteries connecting the longitudinal neural arteries regress when fusion is completed. If these bridging arteries persist, they result in fenestration of the basilar artery [2]. Most of the aneurysms associated with vertebral fenestration are located at the proximal end of the fenestration. The lateral walls of the fenestrated artery have a normal intrinsic architecture, whereas the medial walls have focal defects at both ends of the fenestration [2]. Microscopically, there are medial layer defects at the proximal and distal ends [5]. In addition to the defects, flow phenomena at the proximal end of the fenestrations, where there
Fig. 2. Left vertebral artery angiogram demonstrating the complete occlusion of the aneurysm with Guglielmi detachable coils.
S. Ohba et al. / Clinical Neurology and Neurosurgery 120 (2014) 113–115
is hemodynamic stress and increased turbulence, may contribute to the formation of the aneurysm [5]. In the present case, treatment of the unruptured aneurysm was essential as the size was not insignificant and the hemodynamic stress was considered to be greater than that in cases without moyamoya disease. We initially performed STA-MCA bypass on the right side to reduce the hemodynamic stress on the posterior circulation and to reduce the risk of significant complications in the perioperative period, considering that the blood supply for the areas of the right PCA and right MCA were primarily covered by the VAs, although some blood flowed to the right PCA via the posterior communicating artery from the right ICA. Therefore, we carefully ensured that perioperative conditions such as hypercapnia, hypocapnia, hypotension, and hypovolemia did not develop, which may have caused ischemic complications [3]. Moreover, parental artery occlusion or stenosis due to factors such as coil migration, mechanical spasm, thrombo-embolism, or dissection during the coil embolization procedure may cause more severe problems if STA-MCA bypass is not performed compared to cases where bypass is performed [4]. Thus, the patient was successfully treated through consecutive procedures, without any additional adverse events.
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4. Conclusion In cases of vertebrobasilar aneurysm with moyamoya disease, the aneurysms should be treated more aggressively as the risk of rupture of the aneurysm is considered to be higher. However, whenever possible in these cases, the bypass should be performed before the treatment of the aneurysm to reduce the risk of severe complications. References [1] Bentura JE, Figueiredo EG, de Monaco BA, Teixeira MJ. Vertebrobasilar artery junction aneurysm associated with fenestration. Arq Neuropsiquiatr 2010;68:312–4. [2] Yoon SM, Chun YI, Kwon Y, Kwun BD. Vertebrobasilar junction aneurysms associated with fenestration: experience of five cases treated with Guglielmi detachable coils. Surg Neurol 2004;61:248–54. [3] Yeon JY, Kim JS, Hong SC. Incidental major artery aneurysms in patients with non-hemorrhagic moyamoya disease. Acta Neurochir (Wien) 2011;153:1263–70. [4] Arai Y, Matsuda K, Isozaki M, Nakajima T, Kikuta K. Ruptured intracranial aneurysms associated with moyamoya disease: three case reports. Neurol Med Chir (Tokyo) 2011;51:774–6. [5] Kubo M, Hacein-Bey L, Varelas PN, Ulmer JL, Lemke DM, Cusick JF. Ruptured saccular aneurysm of distal vertebral artery fenestration managed with Guglielmi detachable coils and intraventricular tissue plasminogen activator. Surg Neurol 2005;63:244–8.
Contents lists available at ScienceDirect
Clinical Neurology and Neurosurgery journal homepage: www.elsevier.com/locate/clineuro
Case report
Concurrent unilateral moyamoya disease and vertebrobasilar junction aneurysm associated with fenestration – Case report and management Shigeo Ohba a,b,∗ , Syunsuke Shibao b , Hideyuki Tomita b , Toru Nakagawa b , Kazunori Akaji c , Hideki Murakami b a
Department of Neurosurgery, Keio University School of Medicine, Tokyo, Japan Department of Neurosurgery, Ashikaga Red Cross Hospital, Ashikaga, Tochigi, Japan c Department of Neurosurgery, Mihara Memorial Hospital, Ohtamachi, Isesaki, Gunma, Japan b
a r t i c l e
i n f o
Article history: Received 2 September 2013 Received in revised form 26 February 2014 Accepted 5 March 2014 Available online 13 March 2014 Keywords: Moyamoya disease Vertebral aneurysm Fenestration STA-MCA bypass
1. Introduction The incidence of fenestration of the basilar artery has been reported to be 1.3–6% in autopsy series and less than 1% in angiographic series [1]. Similar to that noted in arterial bifurcations, fenestrations also have a tendency to develop aneurysms [1]. The incidence of aneurysms is reported to be 7% with basilar fenestrations, and the incidence of fenestrations with vertebrobasilar junction aneurysm is reported to be 35.5% [2]. Intracranial aneurysms are occasionally accompanied by moyamoya disease. These aneurysms are generally classified into 3 subtypes: aneurysms at major arteries, aneurysms at distal peripheral arteries, and aneurysms of moyamoya vessels [3]. Aneurysms at major arteries are likely to occur in the posterior circulation. The gradual reduction of the perfusion in the anterior circulation due to chronic stenosis and occlusion of the internal carotid artery (ICA) increase the hemodynamic stress in the posterior circulation, which may contribute to the development of aneurysms [4].
∗ Corresponding author at: Department of Neurosurgery, Keio University School of Medicine, 35 Shinano-machi, Shinjuku-ku, Tokyo 160-8582, Japan. Tel.: +81 3 5363 3808; fax: +81 3 3354 8053. E-mail address: [email protected] (S. Ohba). http://dx.doi.org/10.1016/j.clineuro.2014.03.003 0303-8467/© 2014 Elsevier B.V. All rights reserved.
In the present report, I describe a case of concurrent moyamoya disease and vertebrobasilar aneurysm that were consecutively treated. 2. Case report A 58-year-old woman presented to our hospital with headache and severe left hemiparesis. She did not have a history of hypertension, and was not receiving antiplatelet nor anticoagulant treatment. Computed tomography (CT) scans indicated right putaminal hemorrhage with intraventricular hemorrhage (Fig. 1A). Magnetic resonance angiography could not clearly indicate the right middle cerebral artery (MCA) and right anterior cerebral artery (ACA), but showed an aneurysm at the vertebral artery. Angiograms indicated stenosis of the terminal position of the right ICA, and the proximal position of the right MCA and ACA with moyamoya vessels, as well as an aneurysm at the vertebrobasilar junction. Moreover, we found that the right posterior cerebral artery (PCA) filled the right hemisphere (Fig. 1B–D). Threedimensional CT angiography revealed that the aneurysm, 7 mm in size, was located at the proximal position of the fenestration (Fig. 1E). Due to arterial changes in the anterior circulation, there appeared to be a hemodynamic burden on the vertebral artery (VA). Although the aneurysm had not ruptured, treatment of the aneurysm was essential, considering the size of the aneurysm and the hemodynamic stress. Therefore, the patient underwent
114
S. Ohba et al. / Clinical Neurology and Neurosurgery 120 (2014) 113–115
Fig. 1. Computed tomography scans on admission revealing right putaminal hemorrhage with intraventricular hemorrhage (A). A right internal carotid artery (ICA) angiogram demonstrating the stenosis of the terminal position of the right ICA, and the proximal position of the right middle cerebral artery and anterior cerebral artery with moyamoya vessels (B). Left vertebral artery angiogram indicating an aneurysm at the vertebrobasilar junction (C). Left vertebral artery angiogram showing that the right hemisphere was filled by the right posterior cerebral artery (D). Three-dimensional computed tomography angiography indicating that the aneurysm is located at the proximal end of the fenestration (E).
right superficial temporal artery (STA)-MCA bypass 2 months after admission. The postoperative course was uneventful, and a right external carotid artery angiogram showed that the right cerebral hemisphere was perfused via the right STA. Two months after the surgery, the patient was referred to another hospital where an endovascular procedure was performed for the aneurysm. The aneurysm was completely occluded by using Guglielmi detachable coils (Fig. 2). The patient’s postoperative course was uneventful. 3. Discussion The basilar artery is formed by the fusion of the bilateral longitudinal neural arteries during the fifth gestational week. During this process, temporary bridging arteries connecting the longitudinal neural arteries regress when fusion is completed. If these bridging arteries persist, they result in fenestration of the basilar artery [2]. Most of the aneurysms associated with vertebral fenestration are located at the proximal end of the fenestration. The lateral walls of the fenestrated artery have a normal intrinsic architecture, whereas the medial walls have focal defects at both ends of the fenestration [2]. Microscopically, there are medial layer defects at the proximal and distal ends [5]. In addition to the defects, flow phenomena at the proximal end of the fenestrations, where there
Fig. 2. Left vertebral artery angiogram demonstrating the complete occlusion of the aneurysm with Guglielmi detachable coils.
S. Ohba et al. / Clinical Neurology and Neurosurgery 120 (2014) 113–115
is hemodynamic stress and increased turbulence, may contribute to the formation of the aneurysm [5]. In the present case, treatment of the unruptured aneurysm was essential as the size was not insignificant and the hemodynamic stress was considered to be greater than that in cases without moyamoya disease. We initially performed STA-MCA bypass on the right side to reduce the hemodynamic stress on the posterior circulation and to reduce the risk of significant complications in the perioperative period, considering that the blood supply for the areas of the right PCA and right MCA were primarily covered by the VAs, although some blood flowed to the right PCA via the posterior communicating artery from the right ICA. Therefore, we carefully ensured that perioperative conditions such as hypercapnia, hypocapnia, hypotension, and hypovolemia did not develop, which may have caused ischemic complications [3]. Moreover, parental artery occlusion or stenosis due to factors such as coil migration, mechanical spasm, thrombo-embolism, or dissection during the coil embolization procedure may cause more severe problems if STA-MCA bypass is not performed compared to cases where bypass is performed [4]. Thus, the patient was successfully treated through consecutive procedures, without any additional adverse events.
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4. Conclusion In cases of vertebrobasilar aneurysm with moyamoya disease, the aneurysms should be treated more aggressively as the risk of rupture of the aneurysm is considered to be higher. However, whenever possible in these cases, the bypass should be performed before the treatment of the aneurysm to reduce the risk of severe complications. References [1] Bentura JE, Figueiredo EG, de Monaco BA, Teixeira MJ. Vertebrobasilar artery junction aneurysm associated with fenestration. Arq Neuropsiquiatr 2010;68:312–4. [2] Yoon SM, Chun YI, Kwon Y, Kwun BD. Vertebrobasilar junction aneurysms associated with fenestration: experience of five cases treated with Guglielmi detachable coils. Surg Neurol 2004;61:248–54. [3] Yeon JY, Kim JS, Hong SC. Incidental major artery aneurysms in patients with non-hemorrhagic moyamoya disease. Acta Neurochir (Wien) 2011;153:1263–70. [4] Arai Y, Matsuda K, Isozaki M, Nakajima T, Kikuta K. Ruptured intracranial aneurysms associated with moyamoya disease: three case reports. Neurol Med Chir (Tokyo) 2011;51:774–6. [5] Kubo M, Hacein-Bey L, Varelas PN, Ulmer JL, Lemke DM, Cusick JF. Ruptured saccular aneurysm of distal vertebral artery fenestration managed with Guglielmi detachable coils and intraventricular tissue plasminogen activator. Surg Neurol 2005;63:244–8.
