Dural Arteriovenous Fistula Mimicking a Brainstem Glioma Lo¨ıc Le Guennec, Delphine Leclercq, Zoltan Szatmary, Ahmed Idbaih, German Reyes-Botero, Jean-Yves Delattre, Dimitri Psimaras From the AP-HP, Groupe Hospitalier Pitie-Salp etri Service de neurologie 2-Mazarin, Paris, France (LLG, AI, GRB, JYD, DP); AP-HP, Groupe Hospitalier Pitie-Salp etri ´ ˆ ere, ` ´ ˆ ere, ` Service de neuroradiologie, Paris, France (DL, ZS); Universite´ Pierre et Marie Curie-Paris 6, Centre de Recherche de l’Institut du Cerveau et de la Moelle Epiniere ` (CRICM), UMRS 975, Paris, France (AI, GRB, JYD, DP); Inserm U 975, Paris, France (AI, GRB, JYD, DP); and CNRS, UMR 7225, Paris, France (AI, GRB, JYD, DP).
ABSTRACT BACKGROUND: Brainstem intracranial dural arteriovenous fistulas are extremely rare and can mimic a glioma at the time of presentation. CASE: We report a patient with an infiltrating brainstem lesion that finally revealed an intracranial dural arteriovenous fistula, with full neurological improvement after embolization. CONCLUSION: A careful radiological study looking for dilated vessels around the brainstem is necessary in the workup of an infiltrating brainstem lesion, in order to rule out intracranial dural arteriovenous fistula.
Keywords: Brainstem tumor, glioma, dural arteriovenous fistula. Acceptance: Received June 3, 2014, and in revised form November 14, 2014. Accepted for publication January 3, 2015. Correspondence: Address correspondence to Lo¨ıc Le Guennec, Neurologie-Mazarin, Departement de Neurologie, Groupe Hospitalier Pitie-Salp etri ´ ´ ˆ ere, ` 47–83, boulevard de l’hopital, 75013 Paris, France. E-mail: [email protected]. ˆ J Neuroimaging 2015;00:1-3. DOI: 10.1111/jon.12220
Introduction Intracranial dural arteriovenous fistulas (DAVFs) are rare. Their incidence were reported to be .5 per 100.000 adults per years,3 and they represent 12% of intracranial arteriovenous lesions.6 Here, we present a patient with perimedullary DAVFs, revealed by venous congestion of the brainstem, mimicking a glial tumor that dramatically improved after fistula embolization in interventional radiology.
Case A 36-year-old man with no previous medical history was admitted to hospital because of a 2 months history of progressive headache, right hemifacial and lingual hypoesthesia, nausea, and vomiting. Brain MRI performed outside our hospital 2 days before his admission showed a T2/FLAIR hyperintensity the medulla oblongata, isointense on T1-weighted sequences (Fig 1), with punctiform contrast enhancement after gadolinium injection. Brainstem glioma was suspected, and the patient was transferred in the neuro-oncology department to complete a workup to eliminate other differential diagnosis. On the first day of his admission, the patient developed vestibular ataxia and fell, having a cranial trauma. Instantly after this head injury, he presented loss of consciousness and generalized tonic-clonic seizure which resolved after administration of 1 mg intravenous clonazepam. A noncontrast-enhanced cranial CT scan showed a posttraumatic hematoma within the right frontal lobe, associated with a subarachnoid hemorrhage. The neuroradiologist asked to reanalyze the brain MRI performed 2 days before outside our hospital, and after viewing the images, the possibility of a vascular underlying lesion was evoked, and an angioscanner was performed. This angioscanner detected an abnormal vascular enhancement around the medulla oblongata
suggestive of DAVF (Fig 2). A possible diagnosis of brainstem venous congestion secondary to DAVF was considered. This vascular abnormality was also present on the initial brain MRI, but wasn’t identified by the nonspecialized radiologist (Fig 3). At this stage, neurological examination showed right hemicorporeal hypoesthesia, vestibular ataxia with left side driving and right nystagmus. A cerebral angiography performed 1 day after the admission revealed a DAVF draining into spinal perimedullary veins (Fig 4). DAVF was supplied by branches of the right external carotid artery, mainly by the ascending pharyngeal artery, the middle meningeal arteries and the internal maxillary artery. According to the Cognard classification this type corresponds to a type V DAVF characterized by perimedullary venous drainage associated to progressive spinal congestion.12 Embolization using n-butyle-2-cyanoacrylate (NCBA) with a transarterial approach was performed to occlude the DAVF (Fig 5). Patient’s symptoms improved immediately after the endovascular intervention, and one week after he returned to his normal lifestyle. Only a right slight hemifacial hypoesthesia persisted. Follow-up angiogram performed 1 month after embolization was normal and brain MRI performed 6 months after the embolization showed a total regression of the T2/FLAIRweighted hyperintensity in the medulla oblongata (Fig 6). One year after the embolization, patient was symptom free.
Discussion Depending on the affected area of the DAVFs, patients can present with symptoms related to the mass effect of the vascular malformation, the arterial steal phenomena or the venous congestion that can lead to subarachnoid hemorrhage and/or venous edema.12 Congestion occurs because of the increasing venous pressure, responsible of slowing drainage of venous
Copyright
◦ 2015 by the American Society of Neuroimaging C
1
Fig 1. FLAIR axial image showing an homogenous hyperintensity of the medulla oblongata.
Fig 3. T1 axial image with gadolinium injection showing abnormal dilated vessels around the medulla oblongata (top of the arrow).
Fig 4. Cerebral angiography of the right external carotid showing a DAVF (arrowhead) supplied by a distal dural branch of the internal maxillar artery (white arrow) and the petrosal branch of the middle meningeal artery (black arrow) and drained into a spinal perimedullary vein (small arrows).
Fig 2. CT-scan with injection showing abnormal dilated vessels around the medulla oblongata (top of the arrow).
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routes of brain and spinal cord.7,8 Perimedullary venous drainage of DAVFs present a high risk of ischemic or hemorrhagic lesion, contrary to DAVFs with sinus drainage.12 At our knowledge, only eight cases of ischemic lesion secondary to a brainstem DAVF have been reported.1,2,7–11 The diagnosis
Fig 5. Cerebral angiography of the right external carotid after embolization. No residual fistula (arrowhead) or perimedullary vein (small arrows) is opacified in the former topography of the fistula.
Fig 6. FLAIR axial image showing a regression of the hyperintensity of the medulla oblongata.
of brainstem DAVF is challenging because, abnormal dilated vessel can be undiagnosed with an unappropriate MRI protocol, and because it can mimics a neoplasm at the time of presentation. Indeed, the detection of a FLAIR hyperintense
brainstem signal should raise the possibility of a brainstem glioma. However, a careful workup looking for evidence of inflammatory, infectious or vascular process is mandatory in this settings.4 In our patient, DAVFs diagnosis was quickly established, even if it was not the first considered diagnosis. Because of the risk associated to the topography, a surgical diagnostic approach is often not recommended in infiltrating lesion of the brainstem. Once a complete workup is negative for other causes of brainstem lesion than gliomas, clinicians are often confronted to decide on a treatment strategy, such as radiotherapy, without histological confirmation of the lesion. In our case, this approach would have been deleterious, illustrating the need for a careful search of indirect signs of DAVF on MRI and CT scan, such as dilated vessels around the brainstem. If DAVF is suspected, a cerebral angiography must be performed which allows to establish the diagnosis and occlude the draining vein. When venous side of the DAVF is accessible by catheterization, the transvenous approach is recommended, with a high occlusion rate.5 In our case transarterial embolization was the only therapeutic option, because the DAVF was not draining into accessible venous sinus. The neurological improvement of our patient after embolization suggests that treatment of DAVF involving the brainstem is effective and outcome favorable.
References 1. Piippo A, Niemela M, van Popta J, et al. Characteristics and long-term outcome of 251 patients with dural arteriovenous fistulas in a defined population. J Neurosurg 2013;118:923-34. doi: 910.3171/2012.3111.JNS111604. 2. Newton TH, Cronqvist S. Involvement of dural arteries in intracranial arteriovenous malformations. Radiology 1969;93: 1071-8. 3. Cognard C, Gobin YP, Pierot L, et al. Cerebral dural arteriovenous fistulas: clinical and angiographic correlation with a revised classification of venous drainage. Radiology 1995;194:671-80. 4. Uchino A, Kato A, Kuroda Y, et al. Pontine venous congestion caused by dural carotid-cavernous fistula: report of two cases. Eur Radiol 1997;7:405-8. 5. Wang HC, Lin WC, Kuo YL, et al. Factors associated with brainstem congestive encephalopathy in dural arteriovenous fistulas. Clin Neurol Neurosurg 2009;111:335-40. doi: 310.1016/j.clineuro.2008.1011.1004. 6. Crum BA, Link M. Intracranial dural arteriovenous fistula mimicking brainstem neoplasm. Neurology 2004;62:2330-1. 7. Iwasaki M, Murakami K, Tomita T, et al. Cavernous sinus dural arteriovenous fistula complicated by pontine venous congestion. A case report. Surg Neurol 2006;65:516-8. 8. Kai Y, Hamada JI, Morioka M, et al. Brain stem venous congestion due to dural arteriovenous fistulas of the cavernous sinus. Acta Neurochir (Wien) 2004;146:1107-11. 9. Lanz M, Thiemann U, Grzyska U, et al. Transient brainstem ischemia and recurrent syncope caused by a dural arteriovenous fistula. Neurology 2003;61:1152-3. 10. Satoh M, Kuriyama M, Fujiwara T, et al. Brain stem ischemia from intracranial dural arteriovenous fistula: case report. Surg Neurol 2005;64:341-5. 11. Reyes-Botero G, Mokhtari K, Martin-Duverneuil N, et al. Adult brainstem gliomas. Oncologist 2012;17:388-97. doi: 10.1634/theoncologist.2011-0335. 12. Gobin YP, Rogopoulos A, Aymard A, et al. Endovascular treatment of intracranial dural arteriovenous fistulas with spinal perimedullary venous drainage. J Neurosurg 1992;77:718-23.
Le Guennec et al: Arteriovenous fistula mimicking a glioma
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ABSTRACT BACKGROUND: Brainstem intracranial dural arteriovenous fistulas are extremely rare and can mimic a glioma at the time of presentation. CASE: We report a patient with an infiltrating brainstem lesion that finally revealed an intracranial dural arteriovenous fistula, with full neurological improvement after embolization. CONCLUSION: A careful radiological study looking for dilated vessels around the brainstem is necessary in the workup of an infiltrating brainstem lesion, in order to rule out intracranial dural arteriovenous fistula.
Keywords: Brainstem tumor, glioma, dural arteriovenous fistula. Acceptance: Received June 3, 2014, and in revised form November 14, 2014. Accepted for publication January 3, 2015. Correspondence: Address correspondence to Lo¨ıc Le Guennec, Neurologie-Mazarin, Departement de Neurologie, Groupe Hospitalier Pitie-Salp etri ´ ´ ˆ ere, ` 47–83, boulevard de l’hopital, 75013 Paris, France. E-mail: [email protected]. ˆ J Neuroimaging 2015;00:1-3. DOI: 10.1111/jon.12220
Introduction Intracranial dural arteriovenous fistulas (DAVFs) are rare. Their incidence were reported to be .5 per 100.000 adults per years,3 and they represent 12% of intracranial arteriovenous lesions.6 Here, we present a patient with perimedullary DAVFs, revealed by venous congestion of the brainstem, mimicking a glial tumor that dramatically improved after fistula embolization in interventional radiology.
Case A 36-year-old man with no previous medical history was admitted to hospital because of a 2 months history of progressive headache, right hemifacial and lingual hypoesthesia, nausea, and vomiting. Brain MRI performed outside our hospital 2 days before his admission showed a T2/FLAIR hyperintensity the medulla oblongata, isointense on T1-weighted sequences (Fig 1), with punctiform contrast enhancement after gadolinium injection. Brainstem glioma was suspected, and the patient was transferred in the neuro-oncology department to complete a workup to eliminate other differential diagnosis. On the first day of his admission, the patient developed vestibular ataxia and fell, having a cranial trauma. Instantly after this head injury, he presented loss of consciousness and generalized tonic-clonic seizure which resolved after administration of 1 mg intravenous clonazepam. A noncontrast-enhanced cranial CT scan showed a posttraumatic hematoma within the right frontal lobe, associated with a subarachnoid hemorrhage. The neuroradiologist asked to reanalyze the brain MRI performed 2 days before outside our hospital, and after viewing the images, the possibility of a vascular underlying lesion was evoked, and an angioscanner was performed. This angioscanner detected an abnormal vascular enhancement around the medulla oblongata
suggestive of DAVF (Fig 2). A possible diagnosis of brainstem venous congestion secondary to DAVF was considered. This vascular abnormality was also present on the initial brain MRI, but wasn’t identified by the nonspecialized radiologist (Fig 3). At this stage, neurological examination showed right hemicorporeal hypoesthesia, vestibular ataxia with left side driving and right nystagmus. A cerebral angiography performed 1 day after the admission revealed a DAVF draining into spinal perimedullary veins (Fig 4). DAVF was supplied by branches of the right external carotid artery, mainly by the ascending pharyngeal artery, the middle meningeal arteries and the internal maxillary artery. According to the Cognard classification this type corresponds to a type V DAVF characterized by perimedullary venous drainage associated to progressive spinal congestion.12 Embolization using n-butyle-2-cyanoacrylate (NCBA) with a transarterial approach was performed to occlude the DAVF (Fig 5). Patient’s symptoms improved immediately after the endovascular intervention, and one week after he returned to his normal lifestyle. Only a right slight hemifacial hypoesthesia persisted. Follow-up angiogram performed 1 month after embolization was normal and brain MRI performed 6 months after the embolization showed a total regression of the T2/FLAIRweighted hyperintensity in the medulla oblongata (Fig 6). One year after the embolization, patient was symptom free.
Discussion Depending on the affected area of the DAVFs, patients can present with symptoms related to the mass effect of the vascular malformation, the arterial steal phenomena or the venous congestion that can lead to subarachnoid hemorrhage and/or venous edema.12 Congestion occurs because of the increasing venous pressure, responsible of slowing drainage of venous
Copyright
◦ 2015 by the American Society of Neuroimaging C
1
Fig 1. FLAIR axial image showing an homogenous hyperintensity of the medulla oblongata.
Fig 3. T1 axial image with gadolinium injection showing abnormal dilated vessels around the medulla oblongata (top of the arrow).
Fig 4. Cerebral angiography of the right external carotid showing a DAVF (arrowhead) supplied by a distal dural branch of the internal maxillar artery (white arrow) and the petrosal branch of the middle meningeal artery (black arrow) and drained into a spinal perimedullary vein (small arrows).
Fig 2. CT-scan with injection showing abnormal dilated vessels around the medulla oblongata (top of the arrow).
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Journal of Neuroimaging Vol 00 No 0 xxx 2015
routes of brain and spinal cord.7,8 Perimedullary venous drainage of DAVFs present a high risk of ischemic or hemorrhagic lesion, contrary to DAVFs with sinus drainage.12 At our knowledge, only eight cases of ischemic lesion secondary to a brainstem DAVF have been reported.1,2,7–11 The diagnosis
Fig 5. Cerebral angiography of the right external carotid after embolization. No residual fistula (arrowhead) or perimedullary vein (small arrows) is opacified in the former topography of the fistula.
Fig 6. FLAIR axial image showing a regression of the hyperintensity of the medulla oblongata.
of brainstem DAVF is challenging because, abnormal dilated vessel can be undiagnosed with an unappropriate MRI protocol, and because it can mimics a neoplasm at the time of presentation. Indeed, the detection of a FLAIR hyperintense
brainstem signal should raise the possibility of a brainstem glioma. However, a careful workup looking for evidence of inflammatory, infectious or vascular process is mandatory in this settings.4 In our patient, DAVFs diagnosis was quickly established, even if it was not the first considered diagnosis. Because of the risk associated to the topography, a surgical diagnostic approach is often not recommended in infiltrating lesion of the brainstem. Once a complete workup is negative for other causes of brainstem lesion than gliomas, clinicians are often confronted to decide on a treatment strategy, such as radiotherapy, without histological confirmation of the lesion. In our case, this approach would have been deleterious, illustrating the need for a careful search of indirect signs of DAVF on MRI and CT scan, such as dilated vessels around the brainstem. If DAVF is suspected, a cerebral angiography must be performed which allows to establish the diagnosis and occlude the draining vein. When venous side of the DAVF is accessible by catheterization, the transvenous approach is recommended, with a high occlusion rate.5 In our case transarterial embolization was the only therapeutic option, because the DAVF was not draining into accessible venous sinus. The neurological improvement of our patient after embolization suggests that treatment of DAVF involving the brainstem is effective and outcome favorable.
References 1. Piippo A, Niemela M, van Popta J, et al. Characteristics and long-term outcome of 251 patients with dural arteriovenous fistulas in a defined population. J Neurosurg 2013;118:923-34. doi: 910.3171/2012.3111.JNS111604. 2. Newton TH, Cronqvist S. Involvement of dural arteries in intracranial arteriovenous malformations. Radiology 1969;93: 1071-8. 3. Cognard C, Gobin YP, Pierot L, et al. Cerebral dural arteriovenous fistulas: clinical and angiographic correlation with a revised classification of venous drainage. Radiology 1995;194:671-80. 4. Uchino A, Kato A, Kuroda Y, et al. Pontine venous congestion caused by dural carotid-cavernous fistula: report of two cases. Eur Radiol 1997;7:405-8. 5. Wang HC, Lin WC, Kuo YL, et al. Factors associated with brainstem congestive encephalopathy in dural arteriovenous fistulas. Clin Neurol Neurosurg 2009;111:335-40. doi: 310.1016/j.clineuro.2008.1011.1004. 6. Crum BA, Link M. Intracranial dural arteriovenous fistula mimicking brainstem neoplasm. Neurology 2004;62:2330-1. 7. Iwasaki M, Murakami K, Tomita T, et al. Cavernous sinus dural arteriovenous fistula complicated by pontine venous congestion. A case report. Surg Neurol 2006;65:516-8. 8. Kai Y, Hamada JI, Morioka M, et al. Brain stem venous congestion due to dural arteriovenous fistulas of the cavernous sinus. Acta Neurochir (Wien) 2004;146:1107-11. 9. Lanz M, Thiemann U, Grzyska U, et al. Transient brainstem ischemia and recurrent syncope caused by a dural arteriovenous fistula. Neurology 2003;61:1152-3. 10. Satoh M, Kuriyama M, Fujiwara T, et al. Brain stem ischemia from intracranial dural arteriovenous fistula: case report. Surg Neurol 2005;64:341-5. 11. Reyes-Botero G, Mokhtari K, Martin-Duverneuil N, et al. Adult brainstem gliomas. Oncologist 2012;17:388-97. doi: 10.1634/theoncologist.2011-0335. 12. Gobin YP, Rogopoulos A, Aymard A, et al. Endovascular treatment of intracranial dural arteriovenous fistulas with spinal perimedullary venous drainage. J Neurosurg 1992;77:718-23.
Le Guennec et al: Arteriovenous fistula mimicking a glioma
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