- Email: [email protected]
Enhanced MR angiography for depiction of spinal dural arteriovenous fistula in the craniocervical junction
196
Correspondences
Figure 2 In post-contrast T1-weighted images homogeneous gadolinium enhancement was observed (A). MR perfusion imaging revealed a prolonged arrival time (measured as time to peak parameter) (B) and a reduced blood volume (C) in the right occipital and parietal lobes being consistent with a hypoperfusion of the affected hemisphere.
postzygotic recombination giving rise to two different cell clones homozygous for either allele have been discussed. We conclude that in our case genetic mosaicism affects growth regulation agents that leads either to hyper- or hypotrophy depending on tissue-specific environmental factors.
Conflict of interest statement No potential conflict of interest relevant to this article was reported.
b
Department of Neuroradiology, Neurozentrum, Albert Ludwigs-Universität Freiburg, Breisacherstr. 64, 79106 Freiburg, Germany ∗ Corresponding author. E-mail address: [email protected] (S. Hellwig).
doi:10.1016/j.neurad.2010.07.001
Enhanced MR angiography for depiction of spinal dural arteriovenous fistula in the craniocervical junction
References [1] Rafai MA, Otmani HE, Boulaajaj FZ, Sibai M, Moutaouakkil F, Chlihi A, et al. Sturge—Weber-Klippel—Trenaunay syndrome (case report). J Mal Vasc 2008;33(1):35—8. [2] Lin DD, Barker PB, Hatfield LA, Comi AM. Dynamic MR perfusion and proton MR spectroscopic imaging in Sturge-Weber syndrome: correlation with neurological symptoms. J Magn Reson Imaging 2006;24(2):274—81. [3] Comi AM. Advances in Sturge-Weber syndrome. Curr Opin Neurol 2006;19(2):124—8. [4] Happle R. Lethal genes surviving by mosaicism: a possible explanation for sporadic birth defects involving the skin. J Am Acad Dermatol 1987;16(4):899—906. [5] Huq AH, Chugani DC, Hukku B, Serajee FJ. Evidence of somatic mosaicism in Sturge-Weber syndrome. Neurology 2002;59(5):780—2. [6] Danarti R, Konig A, Bittar M, Happle R. Inverse Klippel-Trenaunay syndrome: review of cases showing deficient growth. Dermatology 2007;214(2):130—2.
S. Hellwig a,∗ A. Keuler b I. Mader b F. Amtage a a Department of Neurology, Neurozentrum, Albert Ludwigs-Universität Freiburg, Breisacherstr. 64, 79106 Freiburg, Germany
ARM avec injection pour la détection d’une fistule artério-veineuse durale de la jonction craniocervicale A 75-year-old man was suffered from gradually progressing dysesthesia in all extremities. Magnetic resonance (MR) imaging was performed using a 1.5-T scanner (GE Medical System) equipped with an NV Array Coil. Routine MR imaging showed an intramedullary T2 high intensity area from the medulla oblongata to C7 level (Fig. 1A), which was slightly enhanced (Fig. 1B and C) by gadolinium (0.5 mol/L). We could not find any flow voids as dotlike or serpiginous abnormal signals in the subarachnoid space [1]. Three-dimensional (3D) time-of-flight (TOF) fast-spoiled gradient-recalled (FSPGR) MR angiography (TR: 11.2 ms, TE: 2.5 ms, FA: 40◦ , Bw: 20.8 kHz, FOV: 300 × 300 mm2 , matrix size: 512 × 454, section thickness: 0.5 mm) was performed. Array Spatial Sensitivity Encoding Technique for parallel imaging to reduce scanning time and Spec IR for selective fat suppression were used together with zero-fill interpolation (zip2). The data acquisition lasted 3 min 20 s and was performed during the continuous intravenous injection of 20 mL of gadolinium (0.1 mL/s). The images were post-processed, using targeted maximum intensity projection and multiplanar reformation by Advantage Workstation Version 4.3.
Correspondences
Figure 1 A T2-weighed MR image, demonstrating intramedullary hyperintensity from medulla oblongata to C7 level without flow voids (A). T1-weighed MR images before (B) and after (C) intravenous administration of gadolinium, demonstrating slight marginal enhancement.
Enhanced MR angiography showed the shunt point on the dura, along the dorsal surface of the craniocervical junction, where a meningeal branch of the vertebral artery communicated with an intradural perimedullary vein (left posterior spinal medullary vein) (Fig. 2A and B), which was confirmed by the subsequent selective right vertebral angiography. The contrast medium slowly flowed down to C7 level without venous aneurysms (Fig. 3). Under the diagnosis of spinal dural arteriovenous fistula (SDAVF), suboccipital craniotomy and C1 laminectomy were performed. Congestive veins were observed on the dorsal surface of the medulla oblongata. Abnormal vessels around the right posterior inferior cerebel-
197
Figure 3 Anterior-posterior (A) and lateral (B) views of selective right vertebral angiography, demonstrating fistula in the craniocervical junction. Contrast medium slowly flowed down to C7 level without venous aneurysms.
lar artery were coagulated and sectioned. A dilated draining vein, running more ventrally to the spinal cord, was occluded at the point as close as possible to the fistula. Postoperatively, the intramedullary T2 hyperintensity in the spinal cord was only partially resolved but abnormal vessels were completely disappeared (Fig. 2C and D). Neurological function of the patient was partially restored after the surgery. SDAVF located in the craniocervical junction is rare but important as a cause of congestive myelopathy and subarachnoid hemorrhage [2,3]. Selective spinal DSA is the gold standard of diagnostic imaging and required for the planning of the treatment of SDAVF, either by surgical obliteration or by intravascular embolization. However, DSA is more inva-
Figure 2 Sagittal (A, B) and coronal (A, D) 3D-TOF FSPGR MR angiography treated in maximum intensity projection. The shunt with direct communication between the meningeal branch of the right vertebral artery and the left posterior spinal medullary vein was observed in the pre-operative MR angiography (A, C, arrow: shunting point). Abnormal vessels were disappeared in the post-operative MR angiography (B. D).
198 sive, time consuming, expensive, and also it needs high skill of operators in comparison with MR angiography. The addition of MR angiography to routine MR imaging may improve sensitivity in the detection of SDAVF and expedite the subsequent DSA to estimate the localization of vertebral level of the fistula [4—6]. The point of our techniques for enhanced MR angiography is slow and continuous administration of gadolinium during the scanning time to avoid missing target vessels, because gadolinium arrival time to the target vessels was unknown in advance. Using sequential k-space sampling, more vessels with different flow rate could be simultaneously caught and higher spatial resolution could be obtained than using centric k-space.
Conflict of interest statement There is no conflict of interest.
References [1] Jellema K, Tijssen C, van Gijn J. Spinal dural arteriovenous fistulas: a congestive myelopathy that initially mimics a peripheral nerve disorder. Brain 2006;129:3150—64. [2] Mascalchi M, Scazzeri F, Prosetti D, Ferrito G, Salvi F, Quilici N. Dural arteriovenous fistula at the craniocervical junction with perimedullary venous drainage. AJNR 1996;17: 1137—41. [3] Mull M, Nijenhuis RJ, Backes WH, Krings T, Wilmink JT, Thron A. Value and limitations of contrast-enhanced MR angiography
Correspondences in spinal arteriovenous malformations and dural arteriovenous fistulas. AJNR 2007;28:1249—58. [4] Ali S, Cashen TA, Carroll TJ, et al. Time-resolved spinal MR angiography: initial clinical experience in the evaluation of spinal arteriovenous shunts. AJNR 2007;28:1806—10. [5] Farb RI, Kim JK, Willinsky RA, et al. Spinal dural arteriovenous fistula localization with a technique of first-pass gadolinium-enhanced MR angiography: initial experience. Radiology 2002;222:843—50. [6] Luetmer PH, Lane JI, Gilbertson JR, Bernstein MA, Huston 3rd J, Atkinson JL. Preangiographic evaluation of spinal dural arteriovenous fistulas with elliptic centric contrast-enhanced MR angiography and effect on radiation dose and volume of iodinated contrast material. AJNR 2005;26:711—8.
T. Yamashita a S. Takehara b K. Miyazaki c Y. Kitahama a H. Namba a,∗ a Departments of Neurosurgery, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku Hamamatsu, 431-3192, Japan b Department of Neurosurgery, Yaizu City Hospital, Japan c Department of Radiology, Yaizu City Hospital, Japan ∗ Corresponding author. E-mail address: [email protected] (H. Namba).
doi:10.1016/j.neurad.2010.08.003
Correspondences
Figure 2 In post-contrast T1-weighted images homogeneous gadolinium enhancement was observed (A). MR perfusion imaging revealed a prolonged arrival time (measured as time to peak parameter) (B) and a reduced blood volume (C) in the right occipital and parietal lobes being consistent with a hypoperfusion of the affected hemisphere.
postzygotic recombination giving rise to two different cell clones homozygous for either allele have been discussed. We conclude that in our case genetic mosaicism affects growth regulation agents that leads either to hyper- or hypotrophy depending on tissue-specific environmental factors.
Conflict of interest statement No potential conflict of interest relevant to this article was reported.
b
Department of Neuroradiology, Neurozentrum, Albert Ludwigs-Universität Freiburg, Breisacherstr. 64, 79106 Freiburg, Germany ∗ Corresponding author. E-mail address: [email protected] (S. Hellwig).
doi:10.1016/j.neurad.2010.07.001
Enhanced MR angiography for depiction of spinal dural arteriovenous fistula in the craniocervical junction
References [1] Rafai MA, Otmani HE, Boulaajaj FZ, Sibai M, Moutaouakkil F, Chlihi A, et al. Sturge—Weber-Klippel—Trenaunay syndrome (case report). J Mal Vasc 2008;33(1):35—8. [2] Lin DD, Barker PB, Hatfield LA, Comi AM. Dynamic MR perfusion and proton MR spectroscopic imaging in Sturge-Weber syndrome: correlation with neurological symptoms. J Magn Reson Imaging 2006;24(2):274—81. [3] Comi AM. Advances in Sturge-Weber syndrome. Curr Opin Neurol 2006;19(2):124—8. [4] Happle R. Lethal genes surviving by mosaicism: a possible explanation for sporadic birth defects involving the skin. J Am Acad Dermatol 1987;16(4):899—906. [5] Huq AH, Chugani DC, Hukku B, Serajee FJ. Evidence of somatic mosaicism in Sturge-Weber syndrome. Neurology 2002;59(5):780—2. [6] Danarti R, Konig A, Bittar M, Happle R. Inverse Klippel-Trenaunay syndrome: review of cases showing deficient growth. Dermatology 2007;214(2):130—2.
S. Hellwig a,∗ A. Keuler b I. Mader b F. Amtage a a Department of Neurology, Neurozentrum, Albert Ludwigs-Universität Freiburg, Breisacherstr. 64, 79106 Freiburg, Germany
ARM avec injection pour la détection d’une fistule artério-veineuse durale de la jonction craniocervicale A 75-year-old man was suffered from gradually progressing dysesthesia in all extremities. Magnetic resonance (MR) imaging was performed using a 1.5-T scanner (GE Medical System) equipped with an NV Array Coil. Routine MR imaging showed an intramedullary T2 high intensity area from the medulla oblongata to C7 level (Fig. 1A), which was slightly enhanced (Fig. 1B and C) by gadolinium (0.5 mol/L). We could not find any flow voids as dotlike or serpiginous abnormal signals in the subarachnoid space [1]. Three-dimensional (3D) time-of-flight (TOF) fast-spoiled gradient-recalled (FSPGR) MR angiography (TR: 11.2 ms, TE: 2.5 ms, FA: 40◦ , Bw: 20.8 kHz, FOV: 300 × 300 mm2 , matrix size: 512 × 454, section thickness: 0.5 mm) was performed. Array Spatial Sensitivity Encoding Technique for parallel imaging to reduce scanning time and Spec IR for selective fat suppression were used together with zero-fill interpolation (zip2). The data acquisition lasted 3 min 20 s and was performed during the continuous intravenous injection of 20 mL of gadolinium (0.1 mL/s). The images were post-processed, using targeted maximum intensity projection and multiplanar reformation by Advantage Workstation Version 4.3.
Correspondences
Figure 1 A T2-weighed MR image, demonstrating intramedullary hyperintensity from medulla oblongata to C7 level without flow voids (A). T1-weighed MR images before (B) and after (C) intravenous administration of gadolinium, demonstrating slight marginal enhancement.
Enhanced MR angiography showed the shunt point on the dura, along the dorsal surface of the craniocervical junction, where a meningeal branch of the vertebral artery communicated with an intradural perimedullary vein (left posterior spinal medullary vein) (Fig. 2A and B), which was confirmed by the subsequent selective right vertebral angiography. The contrast medium slowly flowed down to C7 level without venous aneurysms (Fig. 3). Under the diagnosis of spinal dural arteriovenous fistula (SDAVF), suboccipital craniotomy and C1 laminectomy were performed. Congestive veins were observed on the dorsal surface of the medulla oblongata. Abnormal vessels around the right posterior inferior cerebel-
197
Figure 3 Anterior-posterior (A) and lateral (B) views of selective right vertebral angiography, demonstrating fistula in the craniocervical junction. Contrast medium slowly flowed down to C7 level without venous aneurysms.
lar artery were coagulated and sectioned. A dilated draining vein, running more ventrally to the spinal cord, was occluded at the point as close as possible to the fistula. Postoperatively, the intramedullary T2 hyperintensity in the spinal cord was only partially resolved but abnormal vessels were completely disappeared (Fig. 2C and D). Neurological function of the patient was partially restored after the surgery. SDAVF located in the craniocervical junction is rare but important as a cause of congestive myelopathy and subarachnoid hemorrhage [2,3]. Selective spinal DSA is the gold standard of diagnostic imaging and required for the planning of the treatment of SDAVF, either by surgical obliteration or by intravascular embolization. However, DSA is more inva-
Figure 2 Sagittal (A, B) and coronal (A, D) 3D-TOF FSPGR MR angiography treated in maximum intensity projection. The shunt with direct communication between the meningeal branch of the right vertebral artery and the left posterior spinal medullary vein was observed in the pre-operative MR angiography (A, C, arrow: shunting point). Abnormal vessels were disappeared in the post-operative MR angiography (B. D).
198 sive, time consuming, expensive, and also it needs high skill of operators in comparison with MR angiography. The addition of MR angiography to routine MR imaging may improve sensitivity in the detection of SDAVF and expedite the subsequent DSA to estimate the localization of vertebral level of the fistula [4—6]. The point of our techniques for enhanced MR angiography is slow and continuous administration of gadolinium during the scanning time to avoid missing target vessels, because gadolinium arrival time to the target vessels was unknown in advance. Using sequential k-space sampling, more vessels with different flow rate could be simultaneously caught and higher spatial resolution could be obtained than using centric k-space.
Conflict of interest statement There is no conflict of interest.
References [1] Jellema K, Tijssen C, van Gijn J. Spinal dural arteriovenous fistulas: a congestive myelopathy that initially mimics a peripheral nerve disorder. Brain 2006;129:3150—64. [2] Mascalchi M, Scazzeri F, Prosetti D, Ferrito G, Salvi F, Quilici N. Dural arteriovenous fistula at the craniocervical junction with perimedullary venous drainage. AJNR 1996;17: 1137—41. [3] Mull M, Nijenhuis RJ, Backes WH, Krings T, Wilmink JT, Thron A. Value and limitations of contrast-enhanced MR angiography
Correspondences in spinal arteriovenous malformations and dural arteriovenous fistulas. AJNR 2007;28:1249—58. [4] Ali S, Cashen TA, Carroll TJ, et al. Time-resolved spinal MR angiography: initial clinical experience in the evaluation of spinal arteriovenous shunts. AJNR 2007;28:1806—10. [5] Farb RI, Kim JK, Willinsky RA, et al. Spinal dural arteriovenous fistula localization with a technique of first-pass gadolinium-enhanced MR angiography: initial experience. Radiology 2002;222:843—50. [6] Luetmer PH, Lane JI, Gilbertson JR, Bernstein MA, Huston 3rd J, Atkinson JL. Preangiographic evaluation of spinal dural arteriovenous fistulas with elliptic centric contrast-enhanced MR angiography and effect on radiation dose and volume of iodinated contrast material. AJNR 2005;26:711—8.
T. Yamashita a S. Takehara b K. Miyazaki c Y. Kitahama a H. Namba a,∗ a Departments of Neurosurgery, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku Hamamatsu, 431-3192, Japan b Department of Neurosurgery, Yaizu City Hospital, Japan c Department of Radiology, Yaizu City Hospital, Japan ∗ Corresponding author. E-mail address: [email protected] (H. Namba).
doi:10.1016/j.neurad.2010.08.003