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Spinal arteriovenous fistulae with a concomitant cauda equina schwannoma
The Spine Journal 8 (2008) 391–393
Spinal arteriovenous fistulae with a concomitant cauda equina schwannoma Kuang-Chen Hung, MDa,b, Yung-Hsiao Chiang, MD, PhDa,* a
Department of Neurological Surgery, Tri-Service General Hospital, No. 325, Sec 2, Cheng-Kung Rd, National Defense Medical Center, National Defense University, Neihu 114, Taipei, Taiwan, Republic of China b Department of Surgery, Division of Neurosurgery, Armed Forces Taichung General Hospital, No. 348, Sec 2, Chung-Shan Rd., Taiping City 411, Taichung County, Taiwan, Republic of China Received 17 July 2006; accepted 26 October 2006
Abstract
BACKGROUND: Perimedullary spinal arteriovenous malformations or direct spinal arteriovenous fistulaes (AVFs) may be associated with other vascular abnormalities, such as arteriovenous malformations, venous ectasis, and aneurysms, but rarely have been reported with intraspinal intradural tumors. PURPOSE: The authors present an interesting case of type IV-A spinal AVF concomitant with a cauda equina schwannoma. STUDY DESIGN: The diagnostic procedures and surgical outcome were described. METHODS: The patient underwent surgery, the vessel feeding the AVFs was identified and cauterized, and the spinal tumor was removed. The fistula was small and located inside the tumor. The pathology revealed AVF and schwannoma, respectively. RESULTS: After surgery, the patient’s symptoms began to improve and subside. Two years after surgery, follow-up magnetic resonance imaging showed no vascular lesion and tumor in the spinal canal. CONCLUSIONS: The association of spinal AVFs and cauda equina schwannoma has not been reported previously in any literature. The patient presents the symptoms of myelopathy associated with a spinal vascular lesion; it has to be noted that a concomitant and related intradural spinal tumor may exist. Ó 2008 Elsevier Inc. All rights reserved.
Keywords:
Arteriovenous fistulae; Cauda equine; Schwannoma; Spine; Surgery
Introduction
Case report
Intradural spinal perimedullary arteriovenous fistulaes (AVFs) account for 15% to 30% of all spinal arteriovenous malformations [1,2]. Here, the authors review a case in which a patient exhibited both a spinal AVF and a cauda equine schwannoma.
A 62-year-old man presented with urinary retention (two trans-urethral resection of prostates [TURPs] 1 year apart) and a progressive spastic paraparesis characterized by 4/5 motor weakness, hyperreflexia, and decreased pain/temperature appreciation in both lower extremities. Magnetic resonance imaging of the thoracolumbar spine showed cord edema and increased signal in the cord extending from T5 to the conus. Additionally, numberous serpentine flow void signals were visualized along the anterior and posterior surfaces of the lower cervical and entire thoracic cord through the L4 level of the cauda equine; an accompanying 2-cm rim-enhanced lesion was visualized at the L4 level surrounded by flow voids (Fig. 1A). Spinal angiography revealed a small arterial branch of the median sacral artery, which drained directly into the venous system (type IV-A AVF) (Fig. 1B). The 1.5-cm schwannoma was removed,
FDA device/drug status: not applicable. Nothing of value received from a commercial entity related to this research. * Corresponding author. Department of Neurological Surgery, TriService General Hospital, No. 325, Sec 2, Cheng-Kung Rd., Neihu 114, Taipei, Taiwan, Republic of China. Tel.: þ886-2-87927177; fax: þ8862-87927178. E-mail address: [email protected] (Y.-H. Chiang) 1529-9430/08/$ – see front matter Ó 2008 Elsevier Inc. All rights reserved. doi:10.1016/j.spinee.2006.10.022
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K.-C. Hung and Y.-H. Chiang / The Spine Journal 8 (2008) 391–393
Fig. 1. (A) Preoperative enhanced T1-weighted images with fat saturation showed a lobulated mass-like lesion in the spinal canal of the L4 level (arrow), associated with engorged, flow-void channels tangled in the spinal canal of the thoracolumbar region (arrowheads). (B) Super-selective angiogram of the median sacral artery showed an engorged arterial feeder (black arrow) and cephalad-draining engorged vein (white arrow) associated with fistula (black curved arrow) at the L4 level. White arrowhead indicated the position of the catheter.
and the AF fistula within its tumor capsule was cauterized (Fig. 2). Postoperatively, the patient’s paraparesis gradually resolved. He returned to work within 3 months, and 2-year postoperative magnetic resonance imaging (Fig. 3A, B) showed no tumor recurrence and the resolution of the AVF.
Fig. 2. Intraoperative photograph. A 1.5 cm in size nerve sheath tumor (star), and lots of dilated, tortuous veins (arrow head,) emanating from the fistula, which was within the tumor, and a small feeding vessel (curve arrow.). Arrow indicated cauda equine.
Discussion Spinal AVF, resulting in blood flow steal-chronic venous hypertension, congestion, or thrombosis, may contribute to spinal cord ischemia or myelopathy characterized by paraparesis and sphincteric dysfunction [2,3]. Magnetic resonance imaging readily detects vascular malformation of the spinal cord documenting low-signal feeding and drainage vessels (flow voids on T2-weighted images) [4]. Schwannomas are typically characterized on T2-weighted and T1-enhanced scans by uniform hyperintensity (95% T2 studies) [5,6]. Surgical intervention is frequently the optimal treatment for type IV-A spinal AVF wherein a small arterial feeding can be identified and cauterized [6]. Simultaneous removal of the schwannoma was also performed. When a 62-year-old man presented with myelopathy and paraparesis, thoracolumbar enhanced magnetic resonance imaging documented both an AVF (lower cervical to L4) and L4 scahwannoma. Simultaneous removal of the tumor and cauterization of the AVF resulted in rapid and
Fig. 3. Two years after surgery, nonenhanced T1-weighted image (A) and T2-weighted image (B) showed no vascular lesion and tumor in the spinal canal of the thoracolumbar region.
K.-C. Hung and Y.-H. Chiang / The Spine Journal 8 (2008) 391–393
permanent (2- year follow-up) resolution of the patient’s symptoms. References [1] DiChiro G, Doppman JL, Dwyer AJ, et al. Tumors and arteriovenous malformations of the spinal cord: assessment using MR. Radiology 1985;156:689–97. [2] Barrow DL, Colohan AR, Dawson R. Intradural perimedullary spinal cord arteriovenous fistulas (type IV spinal cord arteriovenous malformations). J Neurosurg 1994;81:221–9.
393
[3] Tomlinson FH, Rufenacht DA, Sundt TM Jr, et al. Arteriovenous fistulae of the brain and the spinal cord. J Neurosurg 1993;79: 16–27. [4] Mourier KL, Gobin YP, George B, et al. Intradural perimedullary arterovenous fistulae: results of surgical and endovascular treatment in a series of 35 cases. Neurosurgery 1993;32:885–91. [5] Hu HP, Huang QL. Signal intensity correction of MRI with pathological findings in spinal neurinoma. Neuroradiology 1992;34: 98–102. [6] Ishii N, Matsuzawa H, Houkin K, et al. An evaluation of 70 spinal schwannoma using conventional computed tomography and magnetic resonance imaging. Neuroradiology 1991;33:542.
Spinal arteriovenous fistulae with a concomitant cauda equina schwannoma Kuang-Chen Hung, MDa,b, Yung-Hsiao Chiang, MD, PhDa,* a
Department of Neurological Surgery, Tri-Service General Hospital, No. 325, Sec 2, Cheng-Kung Rd, National Defense Medical Center, National Defense University, Neihu 114, Taipei, Taiwan, Republic of China b Department of Surgery, Division of Neurosurgery, Armed Forces Taichung General Hospital, No. 348, Sec 2, Chung-Shan Rd., Taiping City 411, Taichung County, Taiwan, Republic of China Received 17 July 2006; accepted 26 October 2006
Abstract
BACKGROUND: Perimedullary spinal arteriovenous malformations or direct spinal arteriovenous fistulaes (AVFs) may be associated with other vascular abnormalities, such as arteriovenous malformations, venous ectasis, and aneurysms, but rarely have been reported with intraspinal intradural tumors. PURPOSE: The authors present an interesting case of type IV-A spinal AVF concomitant with a cauda equina schwannoma. STUDY DESIGN: The diagnostic procedures and surgical outcome were described. METHODS: The patient underwent surgery, the vessel feeding the AVFs was identified and cauterized, and the spinal tumor was removed. The fistula was small and located inside the tumor. The pathology revealed AVF and schwannoma, respectively. RESULTS: After surgery, the patient’s symptoms began to improve and subside. Two years after surgery, follow-up magnetic resonance imaging showed no vascular lesion and tumor in the spinal canal. CONCLUSIONS: The association of spinal AVFs and cauda equina schwannoma has not been reported previously in any literature. The patient presents the symptoms of myelopathy associated with a spinal vascular lesion; it has to be noted that a concomitant and related intradural spinal tumor may exist. Ó 2008 Elsevier Inc. All rights reserved.
Keywords:
Arteriovenous fistulae; Cauda equine; Schwannoma; Spine; Surgery
Introduction
Case report
Intradural spinal perimedullary arteriovenous fistulaes (AVFs) account for 15% to 30% of all spinal arteriovenous malformations [1,2]. Here, the authors review a case in which a patient exhibited both a spinal AVF and a cauda equine schwannoma.
A 62-year-old man presented with urinary retention (two trans-urethral resection of prostates [TURPs] 1 year apart) and a progressive spastic paraparesis characterized by 4/5 motor weakness, hyperreflexia, and decreased pain/temperature appreciation in both lower extremities. Magnetic resonance imaging of the thoracolumbar spine showed cord edema and increased signal in the cord extending from T5 to the conus. Additionally, numberous serpentine flow void signals were visualized along the anterior and posterior surfaces of the lower cervical and entire thoracic cord through the L4 level of the cauda equine; an accompanying 2-cm rim-enhanced lesion was visualized at the L4 level surrounded by flow voids (Fig. 1A). Spinal angiography revealed a small arterial branch of the median sacral artery, which drained directly into the venous system (type IV-A AVF) (Fig. 1B). The 1.5-cm schwannoma was removed,
FDA device/drug status: not applicable. Nothing of value received from a commercial entity related to this research. * Corresponding author. Department of Neurological Surgery, TriService General Hospital, No. 325, Sec 2, Cheng-Kung Rd., Neihu 114, Taipei, Taiwan, Republic of China. Tel.: þ886-2-87927177; fax: þ8862-87927178. E-mail address: [email protected] (Y.-H. Chiang) 1529-9430/08/$ – see front matter Ó 2008 Elsevier Inc. All rights reserved. doi:10.1016/j.spinee.2006.10.022
392
K.-C. Hung and Y.-H. Chiang / The Spine Journal 8 (2008) 391–393
Fig. 1. (A) Preoperative enhanced T1-weighted images with fat saturation showed a lobulated mass-like lesion in the spinal canal of the L4 level (arrow), associated with engorged, flow-void channels tangled in the spinal canal of the thoracolumbar region (arrowheads). (B) Super-selective angiogram of the median sacral artery showed an engorged arterial feeder (black arrow) and cephalad-draining engorged vein (white arrow) associated with fistula (black curved arrow) at the L4 level. White arrowhead indicated the position of the catheter.
and the AF fistula within its tumor capsule was cauterized (Fig. 2). Postoperatively, the patient’s paraparesis gradually resolved. He returned to work within 3 months, and 2-year postoperative magnetic resonance imaging (Fig. 3A, B) showed no tumor recurrence and the resolution of the AVF.
Fig. 2. Intraoperative photograph. A 1.5 cm in size nerve sheath tumor (star), and lots of dilated, tortuous veins (arrow head,) emanating from the fistula, which was within the tumor, and a small feeding vessel (curve arrow.). Arrow indicated cauda equine.
Discussion Spinal AVF, resulting in blood flow steal-chronic venous hypertension, congestion, or thrombosis, may contribute to spinal cord ischemia or myelopathy characterized by paraparesis and sphincteric dysfunction [2,3]. Magnetic resonance imaging readily detects vascular malformation of the spinal cord documenting low-signal feeding and drainage vessels (flow voids on T2-weighted images) [4]. Schwannomas are typically characterized on T2-weighted and T1-enhanced scans by uniform hyperintensity (95% T2 studies) [5,6]. Surgical intervention is frequently the optimal treatment for type IV-A spinal AVF wherein a small arterial feeding can be identified and cauterized [6]. Simultaneous removal of the schwannoma was also performed. When a 62-year-old man presented with myelopathy and paraparesis, thoracolumbar enhanced magnetic resonance imaging documented both an AVF (lower cervical to L4) and L4 scahwannoma. Simultaneous removal of the tumor and cauterization of the AVF resulted in rapid and
Fig. 3. Two years after surgery, nonenhanced T1-weighted image (A) and T2-weighted image (B) showed no vascular lesion and tumor in the spinal canal of the thoracolumbar region.
K.-C. Hung and Y.-H. Chiang / The Spine Journal 8 (2008) 391–393
permanent (2- year follow-up) resolution of the patient’s symptoms. References [1] DiChiro G, Doppman JL, Dwyer AJ, et al. Tumors and arteriovenous malformations of the spinal cord: assessment using MR. Radiology 1985;156:689–97. [2] Barrow DL, Colohan AR, Dawson R. Intradural perimedullary spinal cord arteriovenous fistulas (type IV spinal cord arteriovenous malformations). J Neurosurg 1994;81:221–9.
393
[3] Tomlinson FH, Rufenacht DA, Sundt TM Jr, et al. Arteriovenous fistulae of the brain and the spinal cord. J Neurosurg 1993;79: 16–27. [4] Mourier KL, Gobin YP, George B, et al. Intradural perimedullary arterovenous fistulae: results of surgical and endovascular treatment in a series of 35 cases. Neurosurgery 1993;32:885–91. [5] Hu HP, Huang QL. Signal intensity correction of MRI with pathological findings in spinal neurinoma. Neuroradiology 1992;34: 98–102. [6] Ishii N, Matsuzawa H, Houkin K, et al. An evaluation of 70 spinal schwannoma using conventional computed tomography and magnetic resonance imaging. Neuroradiology 1991;33:542.