Child's Nerv Syst (1992) 8:347-350
BlllqS
9 Springer-Verlag 1992
Successful surgical obliteration of a huge intradural arteriovenous fistula of the spinal cord in a child Susumu Wakai 1, Satoshi Inoh 1, Hideaki Iwanaga 1, Masakatsu Nagai 2, Toshihiko Sato z, and Jiro Izumi 3 1 Department of Neurosurgery and z Department of Radiology, Dokkyo University School of Medicine, Mibu, Tochigi, 321-02 Japan 3 Department of Neurosurgery, National Tochigi Hospital, Tochigi, Japan Received August 3, 1990
Abstract. We r e p o r t the case o f a n 8 - y e a r - o l d b o y w i t h a h u g e i n t r a d u r a l spinal a r t e r i o v e n o u s fistula (AVF), w h i c h was successfully o b l i t e r a t e d b y surgery. T h e s y m p t o m s were e p i s o d i c h e a d a c h e s a n d p r o g r e s s i v e m o t o r a n d sens o r y deficits. H e h a d suffered a s u b a r a c h n o i d h e m o r r h a g e twice b e f o r e b u t n o ensuing n e u r o l o g i c a l deficits. Neuroradiological examinations revealed an intradural A V F w i t h a h u g e v e n o u s a n e u r y s m v e n t r a l to the spinal c o r d o f C7 to T2, w h i c h was fed b y the left 5th i n t e r c o s t a l a r t e r y a n d the right t h y r o c e r v i c a l artery. T h e s e two feeding arteries were o c c l u d e d i n t r a d u r a l l y j u s t at the v e n o u s aneurysm emerging point. MR images taken sequentially after s u r g e r y d e m o n s t r a t e d c o m p l e t e t h r o m b o s i s a n d s u b s e q u e n t d i s a p p e a r a n c e o f the t h r o m b o s e d m a l f o r m a tion. N e u r o l o g i c a l s y m p t o m s i m p r o v e d g r a d u a l l y . Treatm e n t o f such m a l f o r m a t i o n s is discussed.
Key words: A r t e r i o v e n o u s fistula - S p i n a l c o r d - Venous aneurysm
A r t e r i o v e n o u s m a l f o r m a t i o n s ( A V M s ) o f the spinal c o r d are r a r e in c h i l d r e n [4, 7 - 9 ] . I n t r a d u r a l a r t e r i o v e n o u s fistula ( A V F ) is even rarer. O n l y one such c h i l d h o o d case has b e e n r e p o r t e d h i t h e r t o [3]. T h e a u t h o r s r e c e n t l y t r e a t ed surgically a 9 - y e a r - o l d b o y w i t h a spinal A V F a c c o m p a n i e d b y a h u g e v e n o u s a n e u r y s m b y o b l i t e r a t i n g the two feeding arteries. F o l l o w - u p m a g n e t i c r e s o n a n c e i m a g i n g ( M R I ) s h o w e d c o m p l e t e t h r o m b o s i s o f the lesion w i t h s u b s e q u e n t d i s a p p e a r a n c e o f the t h r o m b o s e d m a l f o r m a t i o n . T h e r a r i t y o f such a u n i q u e case p r o m p t e d us t o r e p o r t it in this study.
Case report This 9-year-old boy was admitted to the neurosurgial service on 2 December 1988 because of episodic headaches and progressive leg
Correspondence to: S. Wakai
weakness. He twice suffered a subarachnoidal hemorrhage (SAH) in September 1985 and 1986 (Fig. 1) without focal neurological deficits. The boy underwent four-vessel cerebral angiography each time at the National Tochigi Hospital but the cause of the SAH was not discovered. He had a moderate headache accompanied with gait disturbance on 5 September /988. Spinal tap yielded no bloodstained cerebrospinal fluid (CSF). The third four-vessel cerebral angiography undertaken at the same hospital was again negative. The patient was referred to our institute for further investigations.
Examination On admission, the boy showed mild motor weakness of the left leg with extensor plantar response, impaired pain sensation on the fight C8 to T4 segments, and impaired pain and tactile sensation on both L3 to L5 segments. Manual muscle test showed 4 + in all left lowerlimb muscles. He was able to walk but not run. Thermography demonstrated decreased temperature on the left half of the body, particularly in the region where sensory function was impaired. MRI of the spinal cord revealed a large signal-void lesion about 3 x 1.5 cm in size between C7 and T2 on both T1- and T2-weighted images (Fig. 2). The lesion was presumed to be a high-flow vascular mass with cine-MRI. Spinal angiography demonstrated an AVF fed by the left fifth intercostal artery and the right thyrocervical artery. Both feeding arteries were emerging into a huge venous aneurysm at the T1 level on the left side. The AVF was possibly being drained ventrally to the azygous venous system (Fig. 3). Intravascular embolization was contemplated initially to occlude the fistula. However, for fear of proximal lodging of embolized material at the narrow portion of the feeding artery (Fig. 3, left), open surgery was attempted instead.
Operation The boy underwent osteoplastic laminotomy in the prone position from C6 through T3 on 14 December 1988. The dural tension was remarkably high. There was CSF retention rostral to the AVE The CSF flooded upon dural incision. Dilated and tortuous red veins were seen on the dorsal surface of the spinal cord, which was displaced to the right by the venous aneurysm located ventrolaterally to the cord. The AVF was notably pulsating. The arachnoid membrane was turbid and tough, presumably due to previous episodes of SAH. The feeding arteries were identified just ventral to the left C8 root foramen. While these two arteries were clipped temporarily
348
Fig. 1. Computed tomography scans taken in September 1985 at the time of the first episode of subarachnoid hemorrhage. There is thin layer of subarachnoid blood in the basal cisterns and substantial ventricular hematomas
Fig. 2. Tl-weighted sagittal (left, TR/ 750, TE/35) and coronal (right, TR/ 640, TE/36) magnetic images show a huge signal void lesion about 3 x 1.5 cm ventral to the spinal cord between the C7 to T2 level. The spinal cord is markedly compressed dorsally Fig. 3. Selective spinal angiograms showing a fistula with a huge venous aneurysm fed by the radicular artery (arrow heads, left) from the left 5th intercostal artery and the right thyrocervical artery (arrow heads, right). Arrow (left) indicates the emerging point of the right thyrocervical artery into a huge venous aneurysm Fig. 4. Selective spinal angiograms after surgery. The fistula has disappeared. Presumably normal medullary artery is opacified via the right thyrocervical artery
349
Fig. 5. Postoperative Tl-weighted MR images (TR/750, TE/35). Left: Two weeks after surgery. The signal void lesion has changed to a hyperintense mass (arrows), indicating the thrombosis. Right: Three months after surgery. Only a small isointense mass (arrows) is seen ventral to the spinal cord; size appears normal
sensory-evoked potentials were recorded every 10 rain for 1 h to ascertain whether or not to compromise the cord function with occlusion. No remarkable changes on SEP records occurred during the 1-h period. Thus, the feeders were electrocoagulated, followed by clipping with hemoclips. The AVF pulsation ceased immediately following the occlusion and did not become reactivated. Excision of the AVF itself was not attempted.
Postoperative course Although motor weakness and sensory disturbance occurred temporarily after surgery, the boy was able to walk without aid within 9 days. He was able to stand on one leg at the time of discharge 1 month after surgery. Postoperative spinal angiography demonstrated complete obliteration of the AVF (Fig. 4). MRI taken 2 weeks after surgery revealed that the flow-void lesion was a hyperintensity mass, which seemed to correspond to a thrombosed venous aneurysm. The thrombosed AVF decreased greatly in size 3 months after surgery and finally disappeared I year after surgery on MRI (Fig. 5). The boy returned to his class 1.5 months after surgery and has never since complained of headache. He is able to run although subtle muscle weakness and sensory disturbance remain in the left foot.
Discussion Spinal A V M s are classified into three m a j o r categories [5]: (1) dural AVF; (2) intramedullary AVM, which is subdivided into glomus and juvenile types [7]; (3) intrathecal p a r a m e d u l l a r y A V F [1, 5 - 7 ] . The m a l f o r m a tion o f our case belongs to the third category. G u e g u e n et al. subdivided it further into three types relative to caliber, length, n u m b e r o f vessels involving the fistula, and its therapeutic modalities. The A V F o f the present case had giant fistula, type 3 [5], which they stated h a d to be occluded by balloon embolization. We chose surgical ligation o f the feeding arteries just at the emerging point to
the fistula instead, for fear o f proximal lodging o f embolized material at the n a r r o w p o r t i o n o f the feeding artery (Fig. 3, left), leading to medullary ischemia. The procedure is extremely effective in alleviating the symptoms, as well as in obliterating the A V F itself. O u r experience suggests that even in type 3 intrathecal AVFs [5], some cases could be amenable to surgical ligation. M R I has p r o v e d to be very effective in diagnosing spinal A V M s [2]. O u r case u n d e r w e n t four-vessel cerebral a n g i o g r a p h y three times before M R I revealed the lesion. In addition to its efficacy in preoperative evaluation, it is obviously useful as a follow-up study after either intravascular or direct o p e n surgery. In our case, consecutive postoperative M R images explicitly d e m o n s t r a t e d the process o f t h r o m b o l i s a t i o n and subsequent disappearance o f the lesion. Thus, excision o f the fistula itself would n o t be needed as r e c o m m e n d e d by G u e g u e n et al.
[5]. E n l a r g e m e n t o f the venous a n e u r y s m might have caused venous hypertension and further compression to the cord, leading to progressive leg weakness, on the one hand, and on the other b l o c k a d e o f C S F circulation by the large pulsating mass m i g h t have caused episodic headaches in this case. After surgery, the b o y experienced no further headaches.
Acknowledgements. Many thanks are extended to Drs. Chikayuki Ochiai and Toshimoto Arai (Department of Neurosurgery, Dokkyo University School of Medicine) for their valuable discussions, and to Dr. Akira Takahashi (Department of Neurosurgery, Kounan Hospital) for his comments on the possibility of intravascular embolization in this case.
References 1. Djindjian M, Djindjian R, Rey A, Hurth M, Houdart R (1977) Intradural extramedullary spinal arterio-venous malformations fed by the anterior spinal artery. Surg Neurol 8:85-93
350 2. Dormont D, Gelbert F, Assoulline E, Reizine D, Helias A, Riche MC, Chiras J, Bories J, Merland JJ (1988) MR imaging of spinal cord arteriovenous malformations at 0.5 T: study of 34 cases. AJNR 9:833-838 3. Eldridge PR, Holland IM, Punt JAG (1989) Spinal arteriovenous malformations in children. Br J Neurosurg 3:393-398 4. Esparza J, Perez-Higueras A, Perez-Diaz C, Ramo C (1987) Arteriovenous malformation of the spinal cord in the neonate. Child's Nerv Syst 3:301-303 5. Gueguen B, Merland JJ, Riche MC, Rey A (1987) Vascular malformations of the spinal cord: intrathecal perimedullary arteriovenous fistulas fed by medullary arteries. Neurology 37: 969979
6. Heros RC, Debrun GM, Ojemann RG, Lasjaunias PL, Naessens PJ (1986) Direct spinal arteriovenous fistula: a new type of spinal AVM. Case report. J Neurosurg 64:134-139 7. Rosenblum B, Oldfield EH, Doppman JL, Di Chiro G (1987) Spinal arteriovenous malformations: a comparison of dural arteriovenous fistulas and intradural AVM's in 81 patients. J Nem-osurg 67:795-802 8. Scarff TB, Reigel DH (1979) Arteriovenous malformations of the spinal cord in children. Child's Brain 5:341-351 9. Tada T, Sakamoto K, Kobayashi N, Tanaka Y (1985) Arteriovenous malformation of the spinal cord in a 17-month-old child. Child's Nerv Syst 1:298-301
BlllqS
9 Springer-Verlag 1992
Successful surgical obliteration of a huge intradural arteriovenous fistula of the spinal cord in a child Susumu Wakai 1, Satoshi Inoh 1, Hideaki Iwanaga 1, Masakatsu Nagai 2, Toshihiko Sato z, and Jiro Izumi 3 1 Department of Neurosurgery and z Department of Radiology, Dokkyo University School of Medicine, Mibu, Tochigi, 321-02 Japan 3 Department of Neurosurgery, National Tochigi Hospital, Tochigi, Japan Received August 3, 1990
Abstract. We r e p o r t the case o f a n 8 - y e a r - o l d b o y w i t h a h u g e i n t r a d u r a l spinal a r t e r i o v e n o u s fistula (AVF), w h i c h was successfully o b l i t e r a t e d b y surgery. T h e s y m p t o m s were e p i s o d i c h e a d a c h e s a n d p r o g r e s s i v e m o t o r a n d sens o r y deficits. H e h a d suffered a s u b a r a c h n o i d h e m o r r h a g e twice b e f o r e b u t n o ensuing n e u r o l o g i c a l deficits. Neuroradiological examinations revealed an intradural A V F w i t h a h u g e v e n o u s a n e u r y s m v e n t r a l to the spinal c o r d o f C7 to T2, w h i c h was fed b y the left 5th i n t e r c o s t a l a r t e r y a n d the right t h y r o c e r v i c a l artery. T h e s e two feeding arteries were o c c l u d e d i n t r a d u r a l l y j u s t at the v e n o u s aneurysm emerging point. MR images taken sequentially after s u r g e r y d e m o n s t r a t e d c o m p l e t e t h r o m b o s i s a n d s u b s e q u e n t d i s a p p e a r a n c e o f the t h r o m b o s e d m a l f o r m a tion. N e u r o l o g i c a l s y m p t o m s i m p r o v e d g r a d u a l l y . Treatm e n t o f such m a l f o r m a t i o n s is discussed.
Key words: A r t e r i o v e n o u s fistula - S p i n a l c o r d - Venous aneurysm
A r t e r i o v e n o u s m a l f o r m a t i o n s ( A V M s ) o f the spinal c o r d are r a r e in c h i l d r e n [4, 7 - 9 ] . I n t r a d u r a l a r t e r i o v e n o u s fistula ( A V F ) is even rarer. O n l y one such c h i l d h o o d case has b e e n r e p o r t e d h i t h e r t o [3]. T h e a u t h o r s r e c e n t l y t r e a t ed surgically a 9 - y e a r - o l d b o y w i t h a spinal A V F a c c o m p a n i e d b y a h u g e v e n o u s a n e u r y s m b y o b l i t e r a t i n g the two feeding arteries. F o l l o w - u p m a g n e t i c r e s o n a n c e i m a g i n g ( M R I ) s h o w e d c o m p l e t e t h r o m b o s i s o f the lesion w i t h s u b s e q u e n t d i s a p p e a r a n c e o f the t h r o m b o s e d m a l f o r m a t i o n . T h e r a r i t y o f such a u n i q u e case p r o m p t e d us t o r e p o r t it in this study.
Case report This 9-year-old boy was admitted to the neurosurgial service on 2 December 1988 because of episodic headaches and progressive leg
Correspondence to: S. Wakai
weakness. He twice suffered a subarachnoidal hemorrhage (SAH) in September 1985 and 1986 (Fig. 1) without focal neurological deficits. The boy underwent four-vessel cerebral angiography each time at the National Tochigi Hospital but the cause of the SAH was not discovered. He had a moderate headache accompanied with gait disturbance on 5 September /988. Spinal tap yielded no bloodstained cerebrospinal fluid (CSF). The third four-vessel cerebral angiography undertaken at the same hospital was again negative. The patient was referred to our institute for further investigations.
Examination On admission, the boy showed mild motor weakness of the left leg with extensor plantar response, impaired pain sensation on the fight C8 to T4 segments, and impaired pain and tactile sensation on both L3 to L5 segments. Manual muscle test showed 4 + in all left lowerlimb muscles. He was able to walk but not run. Thermography demonstrated decreased temperature on the left half of the body, particularly in the region where sensory function was impaired. MRI of the spinal cord revealed a large signal-void lesion about 3 x 1.5 cm in size between C7 and T2 on both T1- and T2-weighted images (Fig. 2). The lesion was presumed to be a high-flow vascular mass with cine-MRI. Spinal angiography demonstrated an AVF fed by the left fifth intercostal artery and the right thyrocervical artery. Both feeding arteries were emerging into a huge venous aneurysm at the T1 level on the left side. The AVF was possibly being drained ventrally to the azygous venous system (Fig. 3). Intravascular embolization was contemplated initially to occlude the fistula. However, for fear of proximal lodging of embolized material at the narrow portion of the feeding artery (Fig. 3, left), open surgery was attempted instead.
Operation The boy underwent osteoplastic laminotomy in the prone position from C6 through T3 on 14 December 1988. The dural tension was remarkably high. There was CSF retention rostral to the AVE The CSF flooded upon dural incision. Dilated and tortuous red veins were seen on the dorsal surface of the spinal cord, which was displaced to the right by the venous aneurysm located ventrolaterally to the cord. The AVF was notably pulsating. The arachnoid membrane was turbid and tough, presumably due to previous episodes of SAH. The feeding arteries were identified just ventral to the left C8 root foramen. While these two arteries were clipped temporarily
348
Fig. 1. Computed tomography scans taken in September 1985 at the time of the first episode of subarachnoid hemorrhage. There is thin layer of subarachnoid blood in the basal cisterns and substantial ventricular hematomas
Fig. 2. Tl-weighted sagittal (left, TR/ 750, TE/35) and coronal (right, TR/ 640, TE/36) magnetic images show a huge signal void lesion about 3 x 1.5 cm ventral to the spinal cord between the C7 to T2 level. The spinal cord is markedly compressed dorsally Fig. 3. Selective spinal angiograms showing a fistula with a huge venous aneurysm fed by the radicular artery (arrow heads, left) from the left 5th intercostal artery and the right thyrocervical artery (arrow heads, right). Arrow (left) indicates the emerging point of the right thyrocervical artery into a huge venous aneurysm Fig. 4. Selective spinal angiograms after surgery. The fistula has disappeared. Presumably normal medullary artery is opacified via the right thyrocervical artery
349
Fig. 5. Postoperative Tl-weighted MR images (TR/750, TE/35). Left: Two weeks after surgery. The signal void lesion has changed to a hyperintense mass (arrows), indicating the thrombosis. Right: Three months after surgery. Only a small isointense mass (arrows) is seen ventral to the spinal cord; size appears normal
sensory-evoked potentials were recorded every 10 rain for 1 h to ascertain whether or not to compromise the cord function with occlusion. No remarkable changes on SEP records occurred during the 1-h period. Thus, the feeders were electrocoagulated, followed by clipping with hemoclips. The AVF pulsation ceased immediately following the occlusion and did not become reactivated. Excision of the AVF itself was not attempted.
Postoperative course Although motor weakness and sensory disturbance occurred temporarily after surgery, the boy was able to walk without aid within 9 days. He was able to stand on one leg at the time of discharge 1 month after surgery. Postoperative spinal angiography demonstrated complete obliteration of the AVF (Fig. 4). MRI taken 2 weeks after surgery revealed that the flow-void lesion was a hyperintensity mass, which seemed to correspond to a thrombosed venous aneurysm. The thrombosed AVF decreased greatly in size 3 months after surgery and finally disappeared I year after surgery on MRI (Fig. 5). The boy returned to his class 1.5 months after surgery and has never since complained of headache. He is able to run although subtle muscle weakness and sensory disturbance remain in the left foot.
Discussion Spinal A V M s are classified into three m a j o r categories [5]: (1) dural AVF; (2) intramedullary AVM, which is subdivided into glomus and juvenile types [7]; (3) intrathecal p a r a m e d u l l a r y A V F [1, 5 - 7 ] . The m a l f o r m a tion o f our case belongs to the third category. G u e g u e n et al. subdivided it further into three types relative to caliber, length, n u m b e r o f vessels involving the fistula, and its therapeutic modalities. The A V F o f the present case had giant fistula, type 3 [5], which they stated h a d to be occluded by balloon embolization. We chose surgical ligation o f the feeding arteries just at the emerging point to
the fistula instead, for fear o f proximal lodging o f embolized material at the n a r r o w p o r t i o n o f the feeding artery (Fig. 3, left), leading to medullary ischemia. The procedure is extremely effective in alleviating the symptoms, as well as in obliterating the A V F itself. O u r experience suggests that even in type 3 intrathecal AVFs [5], some cases could be amenable to surgical ligation. M R I has p r o v e d to be very effective in diagnosing spinal A V M s [2]. O u r case u n d e r w e n t four-vessel cerebral a n g i o g r a p h y three times before M R I revealed the lesion. In addition to its efficacy in preoperative evaluation, it is obviously useful as a follow-up study after either intravascular or direct o p e n surgery. In our case, consecutive postoperative M R images explicitly d e m o n s t r a t e d the process o f t h r o m b o l i s a t i o n and subsequent disappearance o f the lesion. Thus, excision o f the fistula itself would n o t be needed as r e c o m m e n d e d by G u e g u e n et al.
[5]. E n l a r g e m e n t o f the venous a n e u r y s m might have caused venous hypertension and further compression to the cord, leading to progressive leg weakness, on the one hand, and on the other b l o c k a d e o f C S F circulation by the large pulsating mass m i g h t have caused episodic headaches in this case. After surgery, the b o y experienced no further headaches.
Acknowledgements. Many thanks are extended to Drs. Chikayuki Ochiai and Toshimoto Arai (Department of Neurosurgery, Dokkyo University School of Medicine) for their valuable discussions, and to Dr. Akira Takahashi (Department of Neurosurgery, Kounan Hospital) for his comments on the possibility of intravascular embolization in this case.
References 1. Djindjian M, Djindjian R, Rey A, Hurth M, Houdart R (1977) Intradural extramedullary spinal arterio-venous malformations fed by the anterior spinal artery. Surg Neurol 8:85-93
350 2. Dormont D, Gelbert F, Assoulline E, Reizine D, Helias A, Riche MC, Chiras J, Bories J, Merland JJ (1988) MR imaging of spinal cord arteriovenous malformations at 0.5 T: study of 34 cases. AJNR 9:833-838 3. Eldridge PR, Holland IM, Punt JAG (1989) Spinal arteriovenous malformations in children. Br J Neurosurg 3:393-398 4. Esparza J, Perez-Higueras A, Perez-Diaz C, Ramo C (1987) Arteriovenous malformation of the spinal cord in the neonate. Child's Nerv Syst 3:301-303 5. Gueguen B, Merland JJ, Riche MC, Rey A (1987) Vascular malformations of the spinal cord: intrathecal perimedullary arteriovenous fistulas fed by medullary arteries. Neurology 37: 969979
6. Heros RC, Debrun GM, Ojemann RG, Lasjaunias PL, Naessens PJ (1986) Direct spinal arteriovenous fistula: a new type of spinal AVM. Case report. J Neurosurg 64:134-139 7. Rosenblum B, Oldfield EH, Doppman JL, Di Chiro G (1987) Spinal arteriovenous malformations: a comparison of dural arteriovenous fistulas and intradural AVM's in 81 patients. J Nem-osurg 67:795-802 8. Scarff TB, Reigel DH (1979) Arteriovenous malformations of the spinal cord in children. Child's Brain 5:341-351 9. Tada T, Sakamoto K, Kobayashi N, Tanaka Y (1985) Arteriovenous malformation of the spinal cord in a 17-month-old child. Child's Nerv Syst 1:298-301
