Spinal Dural AVFs: Classifications and Advanced Imaging

AbstractSpinal dural arteriovenous fistulas (SDAVFs) are the most common vascular shunts of the spine. They occur predominantly in men (more than 80%), commonly involve the thoracolumbar spine, and usually cause progressive myelopathy because of venous congestion of the spinal cord. Recent advanced imaging technology can visualize the detailed angioarchitecture of the spinal cord, and this provides more information of the regional microanatomy related with the shunt disease. We retrospectively analyzed the location of the shunt with adjacent vasculatures and assessed the efficacy and the sensitivity of each imaging modality. Based on these data, a new concept of classification for SDAVFs was reviewed.

Clinical presentation and prognostic factors of spinal dural arteriovenous fistulas: an overview

Neurosurgical FOCUS ◽

10.3171/2012.1.focus11376 ◽

2012 ◽

Vol 32 (5) ◽

pp. E17 ◽

Cited By ~ 40

Author(s):

Jennifer E. Fugate ◽

Giuseppe Lanzino ◽

Alejandro A. Rabinstein

Keyword(s):

Spinal Cord ◽

Clinical Symptoms ◽

Neurological Deficits ◽

Intramedullary Spinal Cord ◽

Lower Extremity Weakness ◽

Arteriovenous Fistulas ◽

Signal Abnormality ◽

Sensory Disturbances ◽

Spinal dural arteriovenous fistulas (AVFs), the most common type of spinal cord vascular malformation, can be a challenge to diagnose and treat promptly. The disorder is rare, and the presenting clinical symptoms and signs are nonspecific and insidious at onset. Spinal dural AVFs preferentially affect middle-aged men, and patients most commonly present with gait abnormality or lower-extremity weakness and sensory disturbances. Symptoms gradually progress or decline in a stepwise manner and are commonly associated with pain and sphincter disturbances. Surgical or endovascular disconnection of the fistula has a high success rate with a low rate of morbidity. Motor symptoms are most likely to improve after treatment, followed by sensory disturbances, and lastly sphincter disturbances. Patients with severe neurological deficits at presentation tend to have worse posttreatment functional outcomes than those with mild or moderate pretreatment disability. However, improvement or stabilization of symptoms is seen in the vast majority of treated patients, and thus treatment is justified even in patients with substantial neurological deficits. The extent of intramedullary spinal cord T2 signal abnormality does not correlate with outcomes and should not be used as a prognostic factor.

Asymptomatic spinal dural arteriovenous fistulas: pathomechanical considerations

10.3171/2012.2.spine11500 ◽

2012 ◽

Vol 16 (5) ◽

pp. 441-446 ◽

Cited By ~ 19

Author(s):

Kenichi Sato ◽

Karel G. TerBrugge ◽

Timo Krings

Keyword(s):

Spinal Cord ◽

Clinical Symptoms ◽

Dorsal Side ◽

Venous Hypertension ◽

Venous Outflow ◽

Arteriovenous Fistulas ◽

Asymptomatic Patients ◽

Upper Thoracic ◽

Object Spinal dural arteriovenous fistulas (SDAVFs) consist of a shunt with converging feeding vessels arising from radiculomeningeal arteries and draining retrogradely via a radicular vein into the perimedullary veins, thereby causing progressive myelopathy due to venous hypertension in the spinal cord. The purpose of this study was to evaluate the hypothesis that the obstruction of radicular venous outlets could be an additional factor inducing symptomatic venous hypertension due to a decreased outflow in SDAVFs. Methods The authors compared the clinical and imaging findings in patients with asymptomatic SDAVFs identified incidentally at the upper thoracic region with the findings in symptomatic patients who harbored SDAVFs at the same level. Results All symptomatic patients presented with medullary dysfunction. The mean age of patients with asymptomatic SDAVF was 51.5 years, approximately 10 years younger than the patients with symptomatic SDAVF (64.1 years old). Despite the existence of dilated perimedullary vessels in the dorsal side of the spinal cord in all patients, the spinal cord edema seen in symptomatic patients was not detected on the MR images obtained in patients with asymptomatic SDAVF. The spinal angiograms of the asymptomatic patients distinctively demonstrated early radicular venous outflow from affected perimedullary veins to the extradural venous plexus as a potential alternate route for the venous hypertension to be released. Conclusions Obstruction of the radicular venous outflow could be an important factor in inducing spinal congestive edema due to venous hypertension, as well as subsequent clinical symptoms of SDAVFs.

Spinal epidural arteriovenous fistula with perimedullary drainage

10.3171/spi.2006.5.4.353 ◽

2006 ◽

Vol 5 (4) ◽

pp. 353-358 ◽

Cited By ~ 51

Author(s):

Timo Krings ◽

Michael Mull ◽

Azize Bostroem ◽

Juergen Otto ◽

Franz J. Hans ◽

...

Keyword(s):

Venous Congestion ◽

Resonance Imaging ◽

Rare Type ◽

Arteriovenous Fistulas ◽

Arteriovenous Shunts ◽

Complete Obliteration ◽

Spinal Dural Arteriovenous Fistulas ◽

Spinal Epidural

✓ The classic angiographically demonstrated features of spinal dural arteriovenous fistulas are shunts of radiculomeningeal branches with radicular veins draining exclusively in the direction of perimedullary veins and thereby causing venous congestion. These shunts are located at the point where the radicular vein passes the dura mater. Spinal epidural arteriovenous shunts, however, normally do not drain into the perimedullary veins and are, therefore, asymptomatic, presumably because of a postulated reflux-impeding mechanism between the dural sleeves. The authors report on a patient in whom an epidural arteriovenous shunt showed delayed retrograde drainage into perimedullary veins, leading to the classic clinical (and magnetic resonance imaging–based) findings of venous congestion. Intraoperatively the angiographically established diagnosis was confirmed. Coagulation of both the epidural shunt zone and the radicular vein resulted in complete obliteration of the fistula, as confirmed on repeated angiography. This rare type of fistula should stimulate considerations on the role of valvelike mechanisms normally impeding retrograde flow from the epidural plexus to perimedullary veins and suggest that, in certain pathological circumstances, epidural fistulas can drain retrogradely into perimedullary veins as an infrequent variant of spinal arteriovenous shunts.

Spinal Dural Arteriovenous Fistula Presenting with Myelopathy

Cerebrovascular Neurosurgery ◽

10.1093/med/9780190887728.003.0030 ◽

2019 ◽

pp. 279-286

Author(s):

Vinayak Narayan ◽

Anil Nanda

Keyword(s):

Spinal Cord ◽

Arteriovenous Malformations ◽

Dural Arteriovenous Fistula ◽

Endovascular Embolization ◽

Spinal Dural Arteriovenous Fistula ◽

Arteriovenous Fistulas ◽

Degenerative Spinal Disease ◽

Spinal Arteriovenous Malformations ◽

Abstract: Spinal dural arteriovenous fistulas are a rare cause of congestive myelopathy. Symptoms are insidious in onset and may be confused with degenerative spinal disease. MRI characteristically shows edema of the spinal cord with serpiginous flow voids that follow the surface of the spinal cord. Careful evaluation with spinal angiography is required to ensure accurate diagnosis. Spinal dural arteriovenous fistulas differ from spinal arteriovenous malformations in that most fistulas have only a single fistulous point without a nidus. Spinal dural arteriovenous fistulas may be treated successfully with either surgical resection or endovascular embolization depending on their anatomy. Earlier treatment is associated with better outcomes.

Spinal dural arteriovenous fistula associated with a spinal perimedullary fistula

10.3171/spi.2006.4.3.241 ◽

2006 ◽

Vol 4 (3) ◽

pp. 241-245 ◽

Cited By ~ 20

Author(s):

Timo Krings ◽

Volker A. Coenen ◽

Martin Weinzierl ◽

Marcus H. T. Reinges ◽

Michael Mull ◽

...

Keyword(s):

Spinal Cord ◽

Arteriovenous Fistula ◽

Dural Arteriovenous Fistula ◽

Vascular Malformations ◽

Venous Drainage ◽

Elevated Pressure ◽

Spinal Dural Arteriovenous Fistula ◽

Arteriovenous Fistulas ◽

Progressive Myelopathy ◽

Dural Arteriovenous Fistulas

✓ Among spinal cord vascular malformations, dural arteriovenous fistulas (DAVFs) must be distinguished from intradural malformations. The concurrence of both is extremely rare. The authors report the case of a 35-year-old man who suffered from progressive myelopathy and who harbored both a DAVF and an intradural perimedullary fistula. During surgery, both fistulas were identified, confirmed, and subsequently obliterated. The fistulas were located at two levels directly adjacent to each other. Although the incidence of concurrent spinal DAVFs is presumed to be approximately 2%, the combination of a dural and an intradural fistula is exceedingly rare; only two other cases have been reported in the literature. One can speculate whether the alteration in venous drainage caused by the (presumably congenital) perimedullary fistula could possibly promote the production of a second dural fistula due to elevated pressure with concomitant venous stagnation and subsequent thrombosis. The authors conclude that despite the rarity of dual pathological entities, the clinician should be aware of the possibility of the concurrence of more than one spinal fistula in the same patient.

Mirror-Image Spinal Dural Arteriovenous Fistulas at the Craniocervical Junction

Neurosurgery ◽

10.1227/neu.0b013e318223bab5 ◽

2011 ◽

Vol 69 (5) ◽

pp. E1166-E1171 ◽

Cited By ~ 10

Author(s):

Jumpei Oshita ◽

Satoshi Yamaguchi ◽

Shinji Ohba ◽

Kaoru Kurisu

Keyword(s):

Spinal Cord ◽

Urinary Incontinence ◽

Computed Tomographic Angiography ◽

Craniocervical Junction ◽

Computed Tomographic ◽

Arteriovenous Fistulas ◽

Mirror Site ◽

Tomographic Angiography ◽

Abstract BACKGROUND AND IMPORTANCE We report an extremely rare case with mirror-site spinal dural arteriovenous fistulas (DAVFs) at the craniocervical junction. Although multiple spinal DAVFs have been reported in the literature, complete mirror-site lesions with fistulas and feeding arteries in the symmetric position have not been previously described. CLINICAL PRESENTATION A 74-year-old man presented with walking disturbance, urinary incontinence, and constipation progressing over a 14-month period. T2-weighted magnetic resonance imaging showed a high-intensity area in the spinal cord at the level from C4 to C6 and multiple flow voids at the surface of the spinal cord. Three-dimensional computed tomographic angiography revealed bilateral DAVFs located in the mirror site of the craniocervical junction. Direct surgery with suboccipital craniectomy and C1 laminectomy revealed dilated tortuous red veins on the dorsal surface of the spinal cord. We found bilateral symmetric red veins around the dural penetration of the vertebral artery. Both red veins were successfully interrupted with the aneurysmal clips. Postoperative 3-dimensional computed tomographic angiography revealed a disappearance of the bilateral fistulas. Magnetic resonance images obtained 6 months after the surgery confirmed the disappearance of the intramedullary high-intensity area and flow voids. The symptoms before the operation improved after surgery, especially urinary incontinence and constipation, with slight walking disturbance. CONCLUSION Because fistulas in the present case existed at the same spinal level, we found multiple fistulas on the first examination. This early notification resulted in a good outcome from the first operation. If patients with spinal DAVFs have rapidly progressing symptoms, one should suspect multiple fistulas.

Spinal Dural Arteriovenous Fistulas (FAVDR) with Peri- Medullary Venous Drainage: Clinical, Radiological and Therapeutic Aspects (Case Report and Literature Review)

European Journal of Medical and Health Sciences ◽

10.24018/ejmed.2021.3.5.1056 ◽

2021 ◽

Vol 3 (5) ◽

pp. 32-33

Author(s):

Tarek Mesbahi ◽

Abderrahmane Rafiq ◽

Nidal Amara ◽

Marouane Makhchoune ◽

Abdelhakim Lakhdar

Keyword(s):

Spinal Cord ◽

Case Report ◽

Clinical Picture ◽

Standard Treatment ◽

Venous Drainage ◽

Cord Compression ◽

Arteriovenous Fistulas ◽

Chronic Myelopathy ◽

Spinal dural arteriovenous fistulas are rare and often unrecognized, they occur predominantly in men, with an initial clinical picture most often misleading made of chronic myelopathy in the absence of treatment, the evolution is slowly towards a definitive paraplegia. We report the case of a patient referred for a table of spinal cord compression revealing a spinal dural fistula with perimedullary venous drainage treated urgently, due to the worsening of the clinical picture. The standard treatment consists of surgical or endovascular exclusion of the fistula (in our case the fistula was surgically excluded). From this case and based on the literature, we will specify the a, clinical, radiological characteristics as well as the prognosis of these malformations, and we will discuss the possibilities of therapeutic management.

Magnetic resonance imaging findings in treated spinal dural arteriovenous fistulas: lack of correlation with clinical outcomes

10.3171/2010.11.spine10178 ◽

2011 ◽

Vol 14 (4) ◽

pp. 548-554 ◽

Cited By ~ 25

Author(s):

Timothy J. Kaufmann ◽

Jonathan M. Morris ◽

Andrea Saladino ◽

Jay N. Mandrekar ◽

Giuseppe Lanzino

Keyword(s):

Spinal Cord ◽

Mr Imaging ◽

Clinical Outcomes ◽

Imaging Findings ◽

Urinary Function ◽

Arteriovenous Fistulas ◽

Imaging Characteristics ◽

Object Little information is available on follow-up MR imaging after treatment of spinal dural arteriovenous fistulas (DAVFs). The authors studied MR imaging findings in treated spinal DAVFs in relation to clinical outcomes. Methods A retrospective review of patients with spinal DAVFs who had undergone both pre- and postoperative spinal MR imaging was conducted. Postoperative MR images were obtained as routine follow-up studies or because of subjective or objective clinical deterioration. Several pre- and posttreatment MR imaging characteristics were evaluated by 2 neuroradiologists blinded to the clinical outcome. Clinical outcomes of motor, sensory, and urinary function (in relation to the patient's preoperative status) at the time of the postoperative MR imaging were obtained from the clinical record. The chi-square, Fisher exact, and rank-sum tests were performed to correlate imaging findings and changes with clinical outcomes. Results Thirty-four patients met inclusion criteria. Treatment was surgical in 33 patients and endovascular in 1 patient. Follow-up MR imaging was performed at a mean 168 ± 107 days after treatment. Twenty-seven patients (79.4%) were either clinically stable or improved, and 7 (20.6%) experienced worsening in one or more clinical outcomes. Most patients were found to have improvement of MR imaging changes. However, some degree of persistent spinal cord signal abnormality, enhancement, and swelling was observed in 31 (91.2%), 29 (85.3%), and 18 (52.3%) patients, respectively. Changes in these MR imaging characteristics compared with preoperative MR imaging did not correlate with clinical outcomes (p > 0.05), with the one exception of a significant correlation between change in urinary function and extent of spinal cord contrast enhancement (p = 0.026), a correlation of uncertain importance. Ten of the 34 patients underwent posttreatment digital subtraction angiography, and 3 of these patients had recurrent/residual DAVFs. Worsening of motor function significantly correlated with recurrent/residual DAVF (p = 0.053). Conclusions Spinal cord abnormalities persist on postoperative MR imaging studies in patients with treated spinal DAVFs, and although they tend to mildly improve with time, these changes may not correlate with clinical outcomes. However, regardless of imaging findings, worsening motor function may correlate with a recurrent or residual DAVF.

“Black butterfly” sign on T2*-weighted and susceptibility-weighted imaging: A novel finding of chronic venous congestion of the brain stem and spinal cord associated with dural arteriovenous fistulas

Journal of the Neurological Sciences ◽

10.1016/j.jns.2017.05.066 ◽

2017 ◽

Vol 379 ◽

pp. 64-68 ◽

Cited By ~ 4

Author(s):

Mikako Enokizono ◽

Noriko Sato ◽

Minoru Morikawa ◽

Yukio Kimura ◽

Atsuhiko Sugiyama ◽

...

Keyword(s):

Spinal Cord ◽

Brain Stem ◽

Venous Congestion ◽

Susceptibility Weighted Imaging ◽

Arteriovenous Fistulas ◽

The Brain

Three-dimensional angioarchitecture of spinal dural arteriovenous fistulas, with special reference to the intradural retrograde venous drainage system

10.3171/2013.1.spine12305 ◽

2013 ◽

Vol 18 (4) ◽

pp. 398-408 ◽

Cited By ~ 15

Author(s):

Keisuke Takai ◽

Taichi Kin ◽

Hiroshi Oyama ◽

Masaaki Shojima ◽

Nobuhito Saito

Keyword(s):

Spinal Cord ◽

Dura Mater ◽

Drainage System ◽

Venous Drainage ◽

Conus Medullaris ◽

University Hospital ◽

Arteriovenous Fistulas ◽

Artery Of Adamkiewicz ◽

Object There have been significant advances in understanding the angioarchitecture of spinal dural arteriovenous fistulas (AVFs). However, the major intradural retrograde venous drainage system has not been investigated in detail, including the most proximal sites of intradural radiculomedullary veins as they connect to the dura mater, which are the final targets of interruption in both microsurgical and endovascular treatments. Methods Between April 1984 and March 2011, 27 patients with 28 AVFs were treated for spinal dural AVFs at the authors' university hospital. The authors assessed vertebral levels of feeding arteries and dural AVFs by using conventional digital subtraction angiography. They also assessed 3D locations of the most proximal sites of intradural radiculomedullary veins and the 3D positional relationship between the major intradural retrograde venous drainage system and intradural neural structures, including the spinal cord, spinal nerves, and the artery of Adamkiewicz, by using operative video recordings plus 3D rotational angiography and/or 3D computer graphics. In addition, they statistically assessed the clinical results of 27 cases. Of these lesions, 23 were treated with open microsurgery and the rest were treated with endovascular methods. Results Feeding arteries consisted of T2–10 intercostal arteries with 19 lesions, T-12 subcostal arteries with 3 lesions, and L1–3 lumbar arteries with 6 lesions. The 3D locations of the targets of interruption (the most proximal sites of intradural radiculomedullary veins as they connect to the dura mater) were identified at the dorsolateral portion of the dura mater adjacent to dorsal roots in all 19 thoracic lesions, whereas they were identified at the ventrolateral portion of the dura mater adjacent to ventral roots in 7 (78%) of 9 cases of conus medullaris/lumbar lesions (p < 0.001). The major intradural retrograde venous drainage system was located dorsal to the spinal cord in all 19 thoracic lesions, whereas it was located ventral to the spinal cord in 4 (44%) of 9 cases of conus/lumbar lesions (p = 0.006). In 3 (11%) of 27 cases, AVFs had a common origin of the artery of Adamkiewicz. In 2 lumbar lesions, the artery of Adamkiewicz ascended very close to the vein because of its ventral location. Although all lesions were successfully obliterated without major complications and both gait and micturition status significantly improved (p = 0.005 and p = 0.015, respectively), conus/lumbar lesions needed careful differential diagnosis from ventral intradural perimedullary AVFs, because the ventral location of these lesions contradicted the Spetzler classification system. Conclusions The angioarchitecture of spinal dural AVFs in the thoracic region is strikingly different from that in conus/lumbar regions with regard to the intradural retrograde venous drainage system. One should keep in mind that spinal dural AVFs are not always dorsal types, especially in conus/lumbar regions.