Case Report
Rupture of an Aneurysm of the Superior Cerebellar Artery Feeding a Dural Arteriovenous Fistula Shinya Kohyama, MD, PhD, Fumitaka Yamane, MD, PhD, Hideaki Ishihara, MD, PhD, Nahoko Uemiya, MD, PhD, and Shoichiro Ishihara, MD, PhD
We experienced a very rare case of bleeding from an aneurysm of a branch of the superior cerebellar artery, which feeds a dural arteriovenous fistula (DAVF) of the posterior fossa. The aneurysm was not detected on initial angiography and 2 episodes of rebleeding resulted in deterioration of the patient’s condition. Although rare, aneurysms of the pial feeding arteries should be considered as a cause of bleeding in cases of DAVF. Key Words: Dural arteriovenous fistula—aneurysm— aneurysmal bleeding—superior cerebellar artery. Ó 2015 by National Stroke Association
An intracranial aneurysm associated with a dural arteriovenous fistula (DAVF) is rare, and most are detected incidentally.1 Aneurysms of the feeding arteries of DAVFs are extremely rare despite an increase in hemodynamic stress because most feeding arteries are covered by the dura mater.2-4 We experienced a case of bleeding from an aneurysm of a branch of the superior cerebral artery, which was a feeding artery of a posterior fossa DAVF. We did not detect the aneurysm at the first onset by cerebral angiography, and rebleeding resulted in deterioration of the patient’s condition. To the best of our knowledge, this is the first case report of bleeding from an aneurysm of the superior cerebellar artery feeding a DAVF. Pitfalls of the treatment for hemorrhage of a DAVF are discussed. From the Department of Endovascular Neurosurgery, International Medical Center, Saitama Medical University, Hidaka, Japan. Received September 29, 2014; revision received November 18, 2014; accepted December 3, 2014. Address correspondence to Shinya Kohyama, MD, PhD, Division of Endovascular Neurosurgery, International Medical Center, Saitama Medical University, Doctor’s Office 309, 1397-1 Yamane, Hidaka, Saitama 350-1298, Japan. E-mail: skohyama@saitama-med. ac.jp. 1052-3057/$ - see front matter Ó 2015 by National Stroke Association http://dx.doi.org/10.1016/j.jstrokecerebrovasdis.2014.12.005
Case Report A 72-year-old man with a sudden onset of headache was transferred to our hospital, where a computed tomography scan revealed intracerebellar, subarachnoid, and subdural hemorrhaging in the posterior fossa (Fig 1, A). Catheter angiography revealed a DAVF, which was primarily fed by the left occipital and right posterior meningeal arteries and drained into the occipital sinus (Fig 2, A). The DAVF was diagnosed as Borden type 2 because of suspected slight cerebellar cortical reflux on angiography, which was considered to be the cause of bleeding at the time. On day 2, the patient’s consciousness deteriorated and a second computed tomography scan showed an increase in the area of the hematoma (Fig 1, B). Posterior decompressive craniotomy and external ventricular drainage were performed subsequent to palliative embolization of the left occipital artery using n-butyl-2cyanoacrylate to reduce blood flow to the DAVF. Although the patient’s condition gradually improved, rebleeding occurred on day 16. A small aneurysm of the left superior cerebellar artery was suspected on a second catheter angiography (Fig 2, B). Retrospective analysis of the first angiography revealed that the aneurysm appeared as a smaller venous pouch, which was enhanced at the capillary phase and lacked continuity with any arteries on 3-dimensional digital subtractive angiography.
Journal of Stroke and Cerebrovascular Diseases, Vol. 24, No. 5 (May), 2015: pp e105-e107
e105
e106
S. KOHYAMA ET AL.
Figure 1. (A) Axial computed tomography (CT) scan of the head on admission showing intracerebellar, subarachnoid, and subdural hemorrhaging in the posterior fossa. (B) Axial CT scan of the head after the first rebleeding showing an increase in the size of the hematoma.
This misinterpretation was probably because of partial thrombosis of the aneurysm and/or acute spasm of the parent artery. Selective angiography of the left superior cerebellar artery demonstrated a saccular aneurysm of a branch feeding the DAVF (Fig 3, A). The aneurysm was obliterated with the parent artery using n-butyl-2cyanoacrylate (Fig 3, B). No rebleeding occurred after the second procedure, although there was a residual shunt from the right posterior meningeal artery. The patient was transferred to another hospital 2 months later with a modified Rankin Scale score of 4.
Discussion There are very few reports of aneurysms originating from the feeding arteries of DAVFs despite an increase in hemodynamic stress because most such feeding arteries are dural and covered by the dura mater.4 The usual cause of bleeding of a DAVF is a rupture of dilated pial draining veins. Dural branches from the intradual
arteries, such as the posterior cerebral or cerebellar arteries, occasionally become feeding arteries for DAVFs.5,6 It is possible that aneurysms form on pial arteries feeding DAVFs and bleed, as seen in cases of pial arteriovenous malformation. However, we can find only 1 such case report in which Gacs et al3 described a case of aneurysmal bleeding of the posterior inferior cerebellar artery feeding a DAVF in their series of 16 cases of peripheral aneurysm, however, the authors did not provide detailed information. Kan et al2 reported a case of an unruptured aneurysm of the anterior inferior cerebellar artery feeding a DAVF, which resolved spontaneously with treatment of the DAVF. There may be some unreported cases in which angiographically occult ruptured aneurysms of the feeding arteries resolved spontaneously with flow reduction by complete obliteration of the DAVF in the acute stage. In our case, flow reduction of other dural feeding arteries might have increased the flow of the pial feeding artery and induced the third rupture of the aneurysm.
Figure 2. (A) Angiography (anteroposterior view) of the left external carotid artery showing a dural arteriovenous fistula (arrow) at the occipital sinus fed by transmastoid branches of the occipital artery (white arrows) and draining mainly into the left transverse sinus. Cortical reflux was not obvious. (B) Angiography (lateral view) of the left vertebral artery after the second instance of rebleeding showing a small aneurysm (arrow) of a distal branch of the left superior cerebellar artery feeding dural arteriovenous fistula at the occipital sinus (white arrow).
ANEURYSMAL RUPTURE ON THE FEEDING ARTERY OF DAVF
e107
Figure 3. (A) Super selective angiography (right oblique view) of a branch of the left superior cerebellar artery showing an aneurysm (arrow) and a dural feeding branch to dural arteriovenous fistula at the occipital sinus (white arrow). (B) Complete obliteration of the aneurysm and the parent artery using n-butyl2-cyanoacrylate.
Conclusion Based on our findings, we recommend that an aneurysm of a pial feeding artery should be considered as a cause of bleeding in cases of DAVF.
References 1. Suzuki S, Tanaka R, Miyasaka Y, et al. Dural arteriovenous malformations associated with cerebral aneurysms. J Clin Neurosci 2000;7(Suppl 1):36-38. 2. Kan P, Stevens EA, Warner J, et al. Resolution of an anterior-inferior cerebellar artery feeding aneurysm with
3.
4.
5. 6.
the treatment of a transverse-sigmoid dural arteriovenous fistula. Skull Base 2007;17:205-210. Gacs G, Vinuela F, Fox AJ, et al. Peripheral aneurysms of the cerebellar arteries. Review of 16 cases. J Neurosurg 1983;58:63-68. Muro K, Adel JG, Gottardi-Littell NR, et al. True aneurysm on the posterior meningeal artery associated with a dural arteriovenous fistula: case report. Neurosurgery 2010; 67:E876-E877. Weil AG, McLaughlin N, Denis D, et al. Tentorial branch of the superior cerebellar artery. Surg Neurol Int 2011;2:71. Lawton MT, Sanchez-Mejia RO, Pham D, et al. Tentorial dural arteriovenous fistulae: operative strategies and microsurgical results for six types. Neurosurgery 2008; 62:110-124. discussion 24-5.
Rupture of an Aneurysm of the Superior Cerebellar Artery Feeding a Dural Arteriovenous Fistula Shinya Kohyama, MD, PhD, Fumitaka Yamane, MD, PhD, Hideaki Ishihara, MD, PhD, Nahoko Uemiya, MD, PhD, and Shoichiro Ishihara, MD, PhD
We experienced a very rare case of bleeding from an aneurysm of a branch of the superior cerebellar artery, which feeds a dural arteriovenous fistula (DAVF) of the posterior fossa. The aneurysm was not detected on initial angiography and 2 episodes of rebleeding resulted in deterioration of the patient’s condition. Although rare, aneurysms of the pial feeding arteries should be considered as a cause of bleeding in cases of DAVF. Key Words: Dural arteriovenous fistula—aneurysm— aneurysmal bleeding—superior cerebellar artery. Ó 2015 by National Stroke Association
An intracranial aneurysm associated with a dural arteriovenous fistula (DAVF) is rare, and most are detected incidentally.1 Aneurysms of the feeding arteries of DAVFs are extremely rare despite an increase in hemodynamic stress because most feeding arteries are covered by the dura mater.2-4 We experienced a case of bleeding from an aneurysm of a branch of the superior cerebral artery, which was a feeding artery of a posterior fossa DAVF. We did not detect the aneurysm at the first onset by cerebral angiography, and rebleeding resulted in deterioration of the patient’s condition. To the best of our knowledge, this is the first case report of bleeding from an aneurysm of the superior cerebellar artery feeding a DAVF. Pitfalls of the treatment for hemorrhage of a DAVF are discussed. From the Department of Endovascular Neurosurgery, International Medical Center, Saitama Medical University, Hidaka, Japan. Received September 29, 2014; revision received November 18, 2014; accepted December 3, 2014. Address correspondence to Shinya Kohyama, MD, PhD, Division of Endovascular Neurosurgery, International Medical Center, Saitama Medical University, Doctor’s Office 309, 1397-1 Yamane, Hidaka, Saitama 350-1298, Japan. E-mail: skohyama@saitama-med. ac.jp. 1052-3057/$ - see front matter Ó 2015 by National Stroke Association http://dx.doi.org/10.1016/j.jstrokecerebrovasdis.2014.12.005
Case Report A 72-year-old man with a sudden onset of headache was transferred to our hospital, where a computed tomography scan revealed intracerebellar, subarachnoid, and subdural hemorrhaging in the posterior fossa (Fig 1, A). Catheter angiography revealed a DAVF, which was primarily fed by the left occipital and right posterior meningeal arteries and drained into the occipital sinus (Fig 2, A). The DAVF was diagnosed as Borden type 2 because of suspected slight cerebellar cortical reflux on angiography, which was considered to be the cause of bleeding at the time. On day 2, the patient’s consciousness deteriorated and a second computed tomography scan showed an increase in the area of the hematoma (Fig 1, B). Posterior decompressive craniotomy and external ventricular drainage were performed subsequent to palliative embolization of the left occipital artery using n-butyl-2cyanoacrylate to reduce blood flow to the DAVF. Although the patient’s condition gradually improved, rebleeding occurred on day 16. A small aneurysm of the left superior cerebellar artery was suspected on a second catheter angiography (Fig 2, B). Retrospective analysis of the first angiography revealed that the aneurysm appeared as a smaller venous pouch, which was enhanced at the capillary phase and lacked continuity with any arteries on 3-dimensional digital subtractive angiography.
Journal of Stroke and Cerebrovascular Diseases, Vol. 24, No. 5 (May), 2015: pp e105-e107
e105
e106
S. KOHYAMA ET AL.
Figure 1. (A) Axial computed tomography (CT) scan of the head on admission showing intracerebellar, subarachnoid, and subdural hemorrhaging in the posterior fossa. (B) Axial CT scan of the head after the first rebleeding showing an increase in the size of the hematoma.
This misinterpretation was probably because of partial thrombosis of the aneurysm and/or acute spasm of the parent artery. Selective angiography of the left superior cerebellar artery demonstrated a saccular aneurysm of a branch feeding the DAVF (Fig 3, A). The aneurysm was obliterated with the parent artery using n-butyl-2cyanoacrylate (Fig 3, B). No rebleeding occurred after the second procedure, although there was a residual shunt from the right posterior meningeal artery. The patient was transferred to another hospital 2 months later with a modified Rankin Scale score of 4.
Discussion There are very few reports of aneurysms originating from the feeding arteries of DAVFs despite an increase in hemodynamic stress because most such feeding arteries are dural and covered by the dura mater.4 The usual cause of bleeding of a DAVF is a rupture of dilated pial draining veins. Dural branches from the intradual
arteries, such as the posterior cerebral or cerebellar arteries, occasionally become feeding arteries for DAVFs.5,6 It is possible that aneurysms form on pial arteries feeding DAVFs and bleed, as seen in cases of pial arteriovenous malformation. However, we can find only 1 such case report in which Gacs et al3 described a case of aneurysmal bleeding of the posterior inferior cerebellar artery feeding a DAVF in their series of 16 cases of peripheral aneurysm, however, the authors did not provide detailed information. Kan et al2 reported a case of an unruptured aneurysm of the anterior inferior cerebellar artery feeding a DAVF, which resolved spontaneously with treatment of the DAVF. There may be some unreported cases in which angiographically occult ruptured aneurysms of the feeding arteries resolved spontaneously with flow reduction by complete obliteration of the DAVF in the acute stage. In our case, flow reduction of other dural feeding arteries might have increased the flow of the pial feeding artery and induced the third rupture of the aneurysm.
Figure 2. (A) Angiography (anteroposterior view) of the left external carotid artery showing a dural arteriovenous fistula (arrow) at the occipital sinus fed by transmastoid branches of the occipital artery (white arrows) and draining mainly into the left transverse sinus. Cortical reflux was not obvious. (B) Angiography (lateral view) of the left vertebral artery after the second instance of rebleeding showing a small aneurysm (arrow) of a distal branch of the left superior cerebellar artery feeding dural arteriovenous fistula at the occipital sinus (white arrow).
ANEURYSMAL RUPTURE ON THE FEEDING ARTERY OF DAVF
e107
Figure 3. (A) Super selective angiography (right oblique view) of a branch of the left superior cerebellar artery showing an aneurysm (arrow) and a dural feeding branch to dural arteriovenous fistula at the occipital sinus (white arrow). (B) Complete obliteration of the aneurysm and the parent artery using n-butyl2-cyanoacrylate.
Conclusion Based on our findings, we recommend that an aneurysm of a pial feeding artery should be considered as a cause of bleeding in cases of DAVF.
References 1. Suzuki S, Tanaka R, Miyasaka Y, et al. Dural arteriovenous malformations associated with cerebral aneurysms. J Clin Neurosci 2000;7(Suppl 1):36-38. 2. Kan P, Stevens EA, Warner J, et al. Resolution of an anterior-inferior cerebellar artery feeding aneurysm with
3.
4.
5. 6.
the treatment of a transverse-sigmoid dural arteriovenous fistula. Skull Base 2007;17:205-210. Gacs G, Vinuela F, Fox AJ, et al. Peripheral aneurysms of the cerebellar arteries. Review of 16 cases. J Neurosurg 1983;58:63-68. Muro K, Adel JG, Gottardi-Littell NR, et al. True aneurysm on the posterior meningeal artery associated with a dural arteriovenous fistula: case report. Neurosurgery 2010; 67:E876-E877. Weil AG, McLaughlin N, Denis D, et al. Tentorial branch of the superior cerebellar artery. Surg Neurol Int 2011;2:71. Lawton MT, Sanchez-Mejia RO, Pham D, et al. Tentorial dural arteriovenous fistulae: operative strategies and microsurgical results for six types. Neurosurgery 2008; 62:110-124. discussion 24-5.
