The Neuroradiology Journal 21: 423-427, 2008
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Abnormal Flow in the Cavernous Sinus Caused by an Asymptomatic Dural Arteriovenous Fistula of the Contralateral Transverse-Sigmoid Sinus A. UCHINO*, R. EGASHIRA**, K. NOMIYAMA**, Y. TAKASE***, T. MINETA***, S. KUDO** * Department of Diagnostic Radiology, Saitama Medical University, International Medical Center; Saitama, Japan ** Department of Radiology; *** Department of Neurosurgery, Saga Medical School, Saga; Japan
Key words: dural arteriovenous fistula, dural carotid-cavernous fistula, magnetic resonance angiography, cerebral angiography
SUMMARY – A 53-year-old asymptomatic man underwent cranial MR imaging to rule out cerebrovascular disease. On T2-weighted axial images abnormal flow voids were detected at the right cavernous sinus, suggesting a dural carotid-cavernous fistula (CCF). On the MR angiogram, abnormal high intensity signals were observed at the right cavernous sinus and the left transversesigmoid (T-S) sinus, suggestive of coexisting right dural CCF and dural arteriovenous fistula (AVF) of the left T-S sinus. Selective cerebral angiography of the left external carotid artery revealed abnormal flow in the right cavernous sinus caused by the dural AVF of the left T-S sinus via the right inferior petrosal sinus due to occlusion of both the distal left sigmoid sinus and proximal right internal jugular vein.
Introduction Dural arteriovenous fistula (AVF) is an acquired vascular lesion involving the dura mater. The most frequently affected sites are the transverse-sigmoid (T-S) sinuses and the cavernous sinuses. An AVF involving the cavernous sinus is called a dural carotid-cavernous fistula (CCF). A dural CCF can be detected as abnormal flow voids in the cavernous sinus with a dilated superior ophthalmic vein on an MR image 1. On the MR angiogram, abnormal high-intensity signals are seen in the affected cavernous sinus 2. We encountered an asymptomatic patient with a dural AVF of the left T-S sinus mimicking a contralateral dural CCF on MR images. Case Report A 53-year-old man without neurological signs or symptoms underwent cranial MR imaging to rule out cerebrovascular disease because his
mother had recently suffered cerebral hemorrhage. On the T2-weighted axial images obtained with a 3-Tesla system (Magnetom Trio, Tim System 3T; Siemens Medical Solutions, Erlangen, Germany) abnormal flow voids were detected at the right cavernous sinus, and both superior ophthalmic veins were mildly dilated, suggesting a dural CCF. However, there was no signal void in either superior ophthalmic vein (figure 1). There was no brain parenchymal abnormality on any pulse sequence (not shown). On MR angiographic source images obtained by the multislab three-dimensional time-of-flight (3D-TOF) technique without contrast media, abnormal signals were seen at the right cavernous sinus and the left T-S sinus, suggesting coexisting right dural CCF and dural AVF of the left T-S sinus. There was, however, no high-intensity signal in either superior ophthalmic vein (figure 2). Subsequent selective cerebral angiography of the left external carotid artery showed a relatively small dural AVF of the left T-S sinus with retrograde flow in the left transverse si423
Abnormal Flow in the Cavernous Sinus Caused by an Asymptomatic Dural Arteriovenous Fistula of the Contralateral ...
A. Uchino
Figure 1 Axial T2-weighted MR image (TR/TE = 4,500/89 ms, 3-Tesla) shows abnormal flow voids in the right cavernous sinus, suggesting dural CCF (long arrow). Both superior ophthalmic veins are mildly dilated, but there is no definite signal void (short arrows).
nus; the distal left sigmoid sinus was occluded. There was antegrade flow in the right T-S sinus via the torcular herophili without reflux into the superior sagittal or straight sinus. Retrograde flow was seen in the right inferior petrosal sinus; the proximal right internal jugular vein was occluded. Finally, the right cavernous sinus was filled, and the left inferior petrosal sinus was antegradely visualized via the intercavernous sinus. There was no reflux into the cortical veins or superior ophthalmic veins (figures 3 and 4). Thus, both superior ophthalmic veins were thrombosed. The dural AVF was also supplied by the lateral tentorial branch arising from the left internal carotid artery (not shown). Right carotid angiography showed no dural CCF on the right side (not shown). The patient was not treated at the time of diagnosis because he was asymptomatic, and the dural AVF was classified as a Cognard type IIa AVF, a low-risk type 3. The clinical course was uneventful during the six months following the angiographic diagnosis. Discussion Dural AVFs including dural CCFs are usually found in patients with various neurological and/or ophthalmologic symptoms and signs. The main symptoms and signs of an AVF of the T-S sinuses are cranial bruit, headache, papilledema, subarachnoid hemorrhage, seizure, tinnitus, visual failure, and mental deterioration 424
. Our patient had no symptom related to the dural AVF because the shunted blood volume was not great and there was no reflux into the cortical veins or superior ophthalmic veins. In patients with a dural CCF, the involved cavernous sinus is usually enlarged and there are anomalous flow voids within it. In our patient, flow voids were detected incidentally in the right cavernous sinus on axial T2-weighted images. Moreover, both superior ophthalmic veins were mildly dilated. These findings suggested a dural CCF. On the MR angiogram and its source images, sinuses with an AVF are usually of high signal intensity due to rapid shunting of blood. In our patient, the right cavernous sinus and the left T-S sinus were hyperintense. Thus, we diagnosed two independent dural AVFs. The final diagnosis was, however, based on selective cerebral angiography, as noted above. Dural non-cavernous sinus AVF can cause symptoms mimicking dural CCF 5-8. However, in one reported series, most such AVFs were located in the inferior petrosal sinus, close to the cavernous sinus 7. To our knowledge, this is the first report of a patient whose dural AVF of the T-S sinus caused an abnormal flow signal in the contralateral cavernous sinus via the torcular herophili. In our patient, although the reason was unknown, there were multiple venous occlusions, and they caused the unique collateral blood flow. On 3D-TOF MR angiograms obtained by the multislab technique, rapidly flowing antegrade blood sometimes appears as a high-intensity 4
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The Neuroradiology Journal 21: 423-427, 2008
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D
Figure 2 MR angiographic images obtained by the multislab three-dimensional time-of-flight technique without contrast media. A-C) Source images show abnormal high-intensity signals in the right cavernous sinus and left transverse-sigmoid (T-S) sinus (long arrows), suggesting both right dural CCF and dural AVF of the left T-S sinus. There is no increased signal in either superior ophthalmic vein (short arrows), indicative of absence of retrograde flow in these veins. D) Infero-superior maximum intensity projection image shows a dural AVF of the left T-S sinus (arrow). However, the right dural CCF cannot be identified clearly.
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Abnormal Flow in the Cavernous Sinus Caused by an Asymptomatic Dural Arteriovenous Fistula of the Contralateral ...
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A. Uchino
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Figure 3 Lateral projection of left external carotid angiography. A) On the early arterial phase image, a dural AVF is seen at the T-S sinus. Feeding arteries are the occipital artery, the posterior auricular artery, and the posterior branch of the middle meningeal artery. B) On the late phase image, the cavernous sinus is opacified via the inferior petrosal sinus. There is no reflux into the cortical veins. X indicates no visualization of the superior ophthalmic veins.
signal in the cavernous and inferior petrosal sinuses 9. Retrograde flow in the left inferior petrosal and cavernous sinuses, detected as a high-intensity signal on the MR angiogram, is occasionally seen because of venous stenosis in the left brachiocephalic vein 10,11. Our case added another possibility for the high-intensity signal in the cavernous sinus: retrograde flow caused by the remote effect of a dural AVF located at a distant site.
There are several treatment methods for dural AVF, with transvenous coil embolization being the most effective 12. Because our patient had a Cognard type IIa dural AVF, a low-risk type 3, intervention was not performed. However, it is well known that the grade of venous drainage of a dural AVF frequently increases during long-term follow-up 13. Thus, our patient will be closely monitored clinically and radiologically.
References 1 Hirabuki N, Miura T, Mitomo M et Al: MR imaging of dural arteriovenous malformations with ocular signs. Neuroradiology 30: 390-394, 1988. 2 Chen JC, Tsuruda JS, Halbach VV: Suspected dural arteriovenous fistula: results with screening MR angiography in seven patients. Radiology 183: 265-271, 1992. 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 194: 671-680, 1995. 4 Obrador S, Soto M, Silvela J: Clinical syndromes of arteriovenous malformations of the transverse-sigmoid sinus. J Neurol Neurosurg Psychiatry 38: 436-451, 1975.
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5 Barnwell SL, Halbach VV, Dowd CF et Al: Dural arteriovenous fistulas involving the inferior petrosal sinus: angiographic findings in six patients. Am J Neuroradiol 11: 511-516, 1990. 6 Mironov A: Dural arteriovenous fistula of the inferior petrosal sinus producing contralateral exophthalmus. Neuroradiology 36: 619-621, 1994. 7 Hasuo K, Matsumoto S, Mihara F et Al: Dural non-cavernous sinus arteriovenous fistulas symptomatically simulating spontaneous carotid-cavernous fistulas: an analysis of angiographic findings. Radiat Med 15: 203208, 1997. 8 Liu HM, Shih HC, Huang YC et Al: Posterior cranial fossa arteriovenous fistula with presenting as caroticocavernous fistula. Neuroradiology 43: 405-408, 2001.
www. centauro. it
The Neuroradiology Journal 21: 423-427, 2008
A
Figure 4 Antero-posterior projection of left external carotid angiography. A-C) Sequential angiograms show abnormal venous flow (arrows): retrograde flow in the left transverse sinus, antegrade flow in the right T-S sinus via the torcular herophili, retrograde flow in the right inferior petrosal sinus, cross flow from the right cavernous sinus to the left cavernous sinus via the intercavernous sinus, and antegrade flow in the left inferior petrosal sinus. X indicates occlusion of the distal left sigmoid sinus. Y indicates occlusion of the proximal right internal jugular vein.
9 Ouanounou S, Tomsick TA, Heitsman C et Al: Cavernous sinus and inferior petrosal sinus flow signal on three-dimensional time-of-flight MR angiography. Am J Neuroradiol 20: 1476-1481, 1999. 10 Paksoy Y, Genc BO, Genc E: Retrograde flow in the left inferior petrosal sinus and blood steal of the cavernous sinus associated with central vein stenosis: MR angiographic findings. Am J Neuroradiol 24: 1364-1368, 2003. 11 Uchino A, Nomiyama K, Takase Y et Al: Retrograde flow in the dural sinuses detected by three-dimensional time-of-flight MR angiography. Neuroradiology 49: 211-215, 2007. 12 Halbach VV, Higashida RT, Hieshima GB et Al: Transvenous embolization of dural fistulas involving the
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C
transverse and sigmoid sinuses. Am J Neuroradiol 10: 385-392, 1989. 13 Cognard C, Houdart E, Casasco A et Al: Long-term changes in intracranial dural arteriovenous fistulae leading to worsening in the type of venous drainage. Neuroradiology 39: 59-66, 1997. Akira Uchino, MD Department of Diagnostic Radiology Saitama Medical University International Medical Center 1397-1 Yamane Hidaka, Saitama 350-1298, Japan E-mail: [email protected]
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Abnormal Flow in the Cavernous Sinus Caused by an Asymptomatic Dural Arteriovenous Fistula of the Contralateral Transverse-Sigmoid Sinus A. UCHINO*, R. EGASHIRA**, K. NOMIYAMA**, Y. TAKASE***, T. MINETA***, S. KUDO** * Department of Diagnostic Radiology, Saitama Medical University, International Medical Center; Saitama, Japan ** Department of Radiology; *** Department of Neurosurgery, Saga Medical School, Saga; Japan
Key words: dural arteriovenous fistula, dural carotid-cavernous fistula, magnetic resonance angiography, cerebral angiography
SUMMARY – A 53-year-old asymptomatic man underwent cranial MR imaging to rule out cerebrovascular disease. On T2-weighted axial images abnormal flow voids were detected at the right cavernous sinus, suggesting a dural carotid-cavernous fistula (CCF). On the MR angiogram, abnormal high intensity signals were observed at the right cavernous sinus and the left transversesigmoid (T-S) sinus, suggestive of coexisting right dural CCF and dural arteriovenous fistula (AVF) of the left T-S sinus. Selective cerebral angiography of the left external carotid artery revealed abnormal flow in the right cavernous sinus caused by the dural AVF of the left T-S sinus via the right inferior petrosal sinus due to occlusion of both the distal left sigmoid sinus and proximal right internal jugular vein.
Introduction Dural arteriovenous fistula (AVF) is an acquired vascular lesion involving the dura mater. The most frequently affected sites are the transverse-sigmoid (T-S) sinuses and the cavernous sinuses. An AVF involving the cavernous sinus is called a dural carotid-cavernous fistula (CCF). A dural CCF can be detected as abnormal flow voids in the cavernous sinus with a dilated superior ophthalmic vein on an MR image 1. On the MR angiogram, abnormal high-intensity signals are seen in the affected cavernous sinus 2. We encountered an asymptomatic patient with a dural AVF of the left T-S sinus mimicking a contralateral dural CCF on MR images. Case Report A 53-year-old man without neurological signs or symptoms underwent cranial MR imaging to rule out cerebrovascular disease because his
mother had recently suffered cerebral hemorrhage. On the T2-weighted axial images obtained with a 3-Tesla system (Magnetom Trio, Tim System 3T; Siemens Medical Solutions, Erlangen, Germany) abnormal flow voids were detected at the right cavernous sinus, and both superior ophthalmic veins were mildly dilated, suggesting a dural CCF. However, there was no signal void in either superior ophthalmic vein (figure 1). There was no brain parenchymal abnormality on any pulse sequence (not shown). On MR angiographic source images obtained by the multislab three-dimensional time-of-flight (3D-TOF) technique without contrast media, abnormal signals were seen at the right cavernous sinus and the left T-S sinus, suggesting coexisting right dural CCF and dural AVF of the left T-S sinus. There was, however, no high-intensity signal in either superior ophthalmic vein (figure 2). Subsequent selective cerebral angiography of the left external carotid artery showed a relatively small dural AVF of the left T-S sinus with retrograde flow in the left transverse si423
Abnormal Flow in the Cavernous Sinus Caused by an Asymptomatic Dural Arteriovenous Fistula of the Contralateral ...
A. Uchino
Figure 1 Axial T2-weighted MR image (TR/TE = 4,500/89 ms, 3-Tesla) shows abnormal flow voids in the right cavernous sinus, suggesting dural CCF (long arrow). Both superior ophthalmic veins are mildly dilated, but there is no definite signal void (short arrows).
nus; the distal left sigmoid sinus was occluded. There was antegrade flow in the right T-S sinus via the torcular herophili without reflux into the superior sagittal or straight sinus. Retrograde flow was seen in the right inferior petrosal sinus; the proximal right internal jugular vein was occluded. Finally, the right cavernous sinus was filled, and the left inferior petrosal sinus was antegradely visualized via the intercavernous sinus. There was no reflux into the cortical veins or superior ophthalmic veins (figures 3 and 4). Thus, both superior ophthalmic veins were thrombosed. The dural AVF was also supplied by the lateral tentorial branch arising from the left internal carotid artery (not shown). Right carotid angiography showed no dural CCF on the right side (not shown). The patient was not treated at the time of diagnosis because he was asymptomatic, and the dural AVF was classified as a Cognard type IIa AVF, a low-risk type 3. The clinical course was uneventful during the six months following the angiographic diagnosis. Discussion Dural AVFs including dural CCFs are usually found in patients with various neurological and/or ophthalmologic symptoms and signs. The main symptoms and signs of an AVF of the T-S sinuses are cranial bruit, headache, papilledema, subarachnoid hemorrhage, seizure, tinnitus, visual failure, and mental deterioration 424
. Our patient had no symptom related to the dural AVF because the shunted blood volume was not great and there was no reflux into the cortical veins or superior ophthalmic veins. In patients with a dural CCF, the involved cavernous sinus is usually enlarged and there are anomalous flow voids within it. In our patient, flow voids were detected incidentally in the right cavernous sinus on axial T2-weighted images. Moreover, both superior ophthalmic veins were mildly dilated. These findings suggested a dural CCF. On the MR angiogram and its source images, sinuses with an AVF are usually of high signal intensity due to rapid shunting of blood. In our patient, the right cavernous sinus and the left T-S sinus were hyperintense. Thus, we diagnosed two independent dural AVFs. The final diagnosis was, however, based on selective cerebral angiography, as noted above. Dural non-cavernous sinus AVF can cause symptoms mimicking dural CCF 5-8. However, in one reported series, most such AVFs were located in the inferior petrosal sinus, close to the cavernous sinus 7. To our knowledge, this is the first report of a patient whose dural AVF of the T-S sinus caused an abnormal flow signal in the contralateral cavernous sinus via the torcular herophili. In our patient, although the reason was unknown, there were multiple venous occlusions, and they caused the unique collateral blood flow. On 3D-TOF MR angiograms obtained by the multislab technique, rapidly flowing antegrade blood sometimes appears as a high-intensity 4
www. centauro. it
The Neuroradiology Journal 21: 423-427, 2008
A
B
C
D
Figure 2 MR angiographic images obtained by the multislab three-dimensional time-of-flight technique without contrast media. A-C) Source images show abnormal high-intensity signals in the right cavernous sinus and left transverse-sigmoid (T-S) sinus (long arrows), suggesting both right dural CCF and dural AVF of the left T-S sinus. There is no increased signal in either superior ophthalmic vein (short arrows), indicative of absence of retrograde flow in these veins. D) Infero-superior maximum intensity projection image shows a dural AVF of the left T-S sinus (arrow). However, the right dural CCF cannot be identified clearly.
425
Abnormal Flow in the Cavernous Sinus Caused by an Asymptomatic Dural Arteriovenous Fistula of the Contralateral ...
A
A. Uchino
B
Figure 3 Lateral projection of left external carotid angiography. A) On the early arterial phase image, a dural AVF is seen at the T-S sinus. Feeding arteries are the occipital artery, the posterior auricular artery, and the posterior branch of the middle meningeal artery. B) On the late phase image, the cavernous sinus is opacified via the inferior petrosal sinus. There is no reflux into the cortical veins. X indicates no visualization of the superior ophthalmic veins.
signal in the cavernous and inferior petrosal sinuses 9. Retrograde flow in the left inferior petrosal and cavernous sinuses, detected as a high-intensity signal on the MR angiogram, is occasionally seen because of venous stenosis in the left brachiocephalic vein 10,11. Our case added another possibility for the high-intensity signal in the cavernous sinus: retrograde flow caused by the remote effect of a dural AVF located at a distant site.
There are several treatment methods for dural AVF, with transvenous coil embolization being the most effective 12. Because our patient had a Cognard type IIa dural AVF, a low-risk type 3, intervention was not performed. However, it is well known that the grade of venous drainage of a dural AVF frequently increases during long-term follow-up 13. Thus, our patient will be closely monitored clinically and radiologically.
References 1 Hirabuki N, Miura T, Mitomo M et Al: MR imaging of dural arteriovenous malformations with ocular signs. Neuroradiology 30: 390-394, 1988. 2 Chen JC, Tsuruda JS, Halbach VV: Suspected dural arteriovenous fistula: results with screening MR angiography in seven patients. Radiology 183: 265-271, 1992. 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 194: 671-680, 1995. 4 Obrador S, Soto M, Silvela J: Clinical syndromes of arteriovenous malformations of the transverse-sigmoid sinus. J Neurol Neurosurg Psychiatry 38: 436-451, 1975.
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5 Barnwell SL, Halbach VV, Dowd CF et Al: Dural arteriovenous fistulas involving the inferior petrosal sinus: angiographic findings in six patients. Am J Neuroradiol 11: 511-516, 1990. 6 Mironov A: Dural arteriovenous fistula of the inferior petrosal sinus producing contralateral exophthalmus. Neuroradiology 36: 619-621, 1994. 7 Hasuo K, Matsumoto S, Mihara F et Al: Dural non-cavernous sinus arteriovenous fistulas symptomatically simulating spontaneous carotid-cavernous fistulas: an analysis of angiographic findings. Radiat Med 15: 203208, 1997. 8 Liu HM, Shih HC, Huang YC et Al: Posterior cranial fossa arteriovenous fistula with presenting as caroticocavernous fistula. Neuroradiology 43: 405-408, 2001.
www. centauro. it
The Neuroradiology Journal 21: 423-427, 2008
A
Figure 4 Antero-posterior projection of left external carotid angiography. A-C) Sequential angiograms show abnormal venous flow (arrows): retrograde flow in the left transverse sinus, antegrade flow in the right T-S sinus via the torcular herophili, retrograde flow in the right inferior petrosal sinus, cross flow from the right cavernous sinus to the left cavernous sinus via the intercavernous sinus, and antegrade flow in the left inferior petrosal sinus. X indicates occlusion of the distal left sigmoid sinus. Y indicates occlusion of the proximal right internal jugular vein.
9 Ouanounou S, Tomsick TA, Heitsman C et Al: Cavernous sinus and inferior petrosal sinus flow signal on three-dimensional time-of-flight MR angiography. Am J Neuroradiol 20: 1476-1481, 1999. 10 Paksoy Y, Genc BO, Genc E: Retrograde flow in the left inferior petrosal sinus and blood steal of the cavernous sinus associated with central vein stenosis: MR angiographic findings. Am J Neuroradiol 24: 1364-1368, 2003. 11 Uchino A, Nomiyama K, Takase Y et Al: Retrograde flow in the dural sinuses detected by three-dimensional time-of-flight MR angiography. Neuroradiology 49: 211-215, 2007. 12 Halbach VV, Higashida RT, Hieshima GB et Al: Transvenous embolization of dural fistulas involving the
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C
transverse and sigmoid sinuses. Am J Neuroradiol 10: 385-392, 1989. 13 Cognard C, Houdart E, Casasco A et Al: Long-term changes in intracranial dural arteriovenous fistulae leading to worsening in the type of venous drainage. Neuroradiology 39: 59-66, 1997. Akira Uchino, MD Department of Diagnostic Radiology Saitama Medical University International Medical Center 1397-1 Yamane Hidaka, Saitama 350-1298, Japan E-mail: [email protected]
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