Perimedullary Venous Drainage Research Articles

Transarterial Embolization of Intracranial Dural Arteriovenous Fistulas Cognard Type V With Direct Drainage Into the Perimedullary Veins: Case Report and Literature Review.

Cognard type V fistula (CVF) is a rare type of dural arteriovenous fistula characterized by spinal perimedullary venous drainage. Owing to the lack of pathognomonic findings, misdiagnosis is common. Patients often undergo multiple spinal angiograms negative for spinal vascular malformations. Digital subtraction angiography is the gold standard diagnostic tool. The preferred treatment option is endovascular management with embolization through a transarterial, transvenous, or combined approach. Other options include open surgery, stereotactic radiosurgery, or a combination of both. The patient from case # 1 presented with progressive weakness and hypoesthesia in the bilateral lower extremities, with urinary and bowel incontinence. The DSA identified a CVF fed by the meningohypophyseal trunk and a draining perimedullary vein. Embolization with 0.1 ccs of Onyx-18 was performed with complete fistula occlusion. The patient from case # 2 developed bilateral lower extremity weakness, diffuse numbness, and urinary incontinence. The DSA showed a CVF fed by tributaries from the ascending pharyngeal artery and posterior meningeal artery branches of the V3 segment, draining into a perimedullary vein. Embolization with 0.3 cc of Onyx-18 was performed with 100% occlusion of the fistula. A 1-year follow-up angiogram confirmed complete fistula occlusion. Both patients consented to the procedure. Even if a patient only presents symptoms of myelopathy, CVF should be considered. Herein, we present 2 cases of CVF with direct drainage into the perimedullary veins which presented exclusively with myelopathy syndrome and describe treatment with trasarterial embolization with Onyx.

Cognard Type Ⅴ Torcular Dural Arteriovenous Fistula: A Rare Entity

Tentorial dural arteriovenous fistulas (DAVFs) are a dangerous subtype of fistula. Lawton etal classified this type of fistula into 6 categories based on specific operative strategies. Clinical manifestations of 6 types of tentorial DAVFs vary to some extent. Cognard type V DAVFs in the tentorial region are usually petrosal/superior petrosal sinus DAVFs. DAVFs with perimedullary venous drainage around the torcular herophili are rare. The veins of the posterior fossa are intricate and variable. There are anatomic communications between the perimedullary vein and cerebellar vein or veins of the brainstem. Almost all of the Cognard type V DAVFs are found in the posterior fossa. Here, we present a Cognard type V DAVF with a fistula located around the torcular herophili.

Our Experience of Eight Patients with Dural Arteriovenous Fistula's at Foramen Magnum with Respect to Presentation, Angioarchitecture, and Endovascular Treatment Outcomes.

Background Dural arteriovenous fistulas (DAVFs) around foramen magnum (FM) with peri medullary venous drainage, are uncommon and have wide spectrum of presentation. Literature about this lesion is sparse. We intent to analyze and report our experience with these cases with respect to presentation, evaluation, and endovascular treatment outcomes. Materials and Methods All the eight patients who were diagnosed with DAVFs at FM and treated with transarterial embolization using ethylene viny alcohol were included in this study. Clinical record sheets, radiological, and angiographic data of these patients were retrieved from our departmental database. Results Duration of symptoms ranged from 1 day to 3 years. Presentation with progressive ascending sensory symptoms and weakness ( N = 4), acute headache ( N = 2) acute quadriplegia ( N = 1), and right ear bruit ( N = 1) was seen. Exclusive feeders from occipital artery (OA) and vertebral artery (VA) were seen in two and four patients, respectively. Dual feeders from a combination of ascending pharyngeal artery and VA; from a combination of OA and VA were seen in one patient each. The exclusive venous drainage to spinal peri medullary veins ( N = 3), brain stem peri medullary veins ( N = 1), and both combined ( N = 4). Two patients had a draining vein aneurysm. Complete obliteration of fistula was achieved in all patients. Complete resolution of symptoms was seen in six patients; two patients had significant improvement. Conclusion The clinical presentation of dural AVF at foramen magnum is wide ranging and these lesions can be treated effectively and safely by transarterial embolization. Duration of symptoms strongly influences the final patient outcome.

Tentorial dural arteriovenous fistula with perimedullary venous drainage-associated cervical myelopathy: illustrative case.

Tentorial dural arteriovenous fistulas (DAVFs) with perimedullary venous drainage causing cervical myelopathy are very uncommon conditions with an extremely aggressive behavior. When the characteristic radiological clues are missing, the unspecific clinical picture may cause delay and make the diagnosis challenging. Here the authors report a case of a 58-year-old man who developed progressive spastic tetraparesis and dyspnea with an extensive mild enhancing cervical cord lesion initially oriented as a neurosyphilis-associated transverse myelitis. Acute worsening after steroid administration redirected the diagnosis, and a tentorial Cognard type V DAVF was elicited. The microsurgical disconnection process is described, and previously documented cases in the literature are reviewed. If a DAVF is highly suspected, it is important to consider the possibility of its intracranial origin, and spinal as well as cerebral arteriography must be performed.

Abstract #2 LATAM Experience: Cost Effectiveness of Endovascular Stroke Therapy. Analysis From a Colombian Healthcare Perspective

Foramen magnum dural arteriovenous fistulas (DAVF) with perimedullary venous drainage represent a small minority of intracranial DAVF, and only a number of small series with limited cases have been reported. The purpose of this retrospective study is to summarize experience of transarterial Onyx embolisation in the treatment of these lesions, with emphasis on the balloon-augmented technique.Five consecutive patients with DAVF at the foramen magnum were treated by transarterial embolisation using the Onyx system. Their symptoms included myelopathy (n = 4) and SAH (n = 1). Suppliers were from the vertebral artery (VA) (n = 4), occipital artery (OA) (n = 4), and ascending pharyngeal artery (APA) (n = 2), with drainage to the perimedullary veins. After catheterization of the dilated supplier, the fistulous connections, proximal draining veins and appropriate distal segment of the feeders of these DAVF were transarterial embolized using Onyx-18. In three patients, balloon-augmented technique was used to assist embolisation. The technical feasibility of the procedure, angiographic results, and clinical outcome were evaluated.In every case, complete obliteration was achieved. Neither intraprocedural vessel rupture nor other procedure-related complications occurred. The results remained stable in all patients on follow-up angiograms (mean, 7.2 months). At the last clinical follow-up (mean, 17.6 months), two patients showed complete resolution of the initial symptoms, and three patients showed significant improvement.We found that Onyx embolisation is a feasible and safe alternative to open surgery in the treatment of selective DAVF at the foramen magnum. The balloon-augmented technique widens indications for transarterial Onyx packing of these lesions, and improved safety of the procedure.

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

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.

Progressive myelopathy due to treatable intracranial dural arterovenous fistulae

Intracranial dural arteriovenous fistulae (DAVF) can rarely have a perimedullary venous drainage (Cognard Type V) resulting in an aggressive but potentially treatable and reversible myelopathy. Early diagnosis is often challenging.

Combined surgical and endovascular approach to treat a carotid cavernous fistula with associated brainstem venous congestion

Endovascular embolization is the standard approach for management of carotid cavernous fistulas (CCFs) due to the ease of access and reduced level of risk associated with the procedure compared with...

“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

A dural arteriovenous fistula (DAVF) with spinal perimedullary venous drainage can cause progressive myelopathy, and it is sometimes incorrectly diagnosed as another spinal cord disease. Here we report the cases of three individuals with a DAVF (one craniocervical junction DAVF and two tentorial DAVFs) with progressive myelopathy showing unique magnetic resonance (MR) imaging findings. MR T2*WI or susceptibility-weighted imaging (SWI) demonstrated symmetrical dark signal intensity lesions predominantly in the dorsal aspect of medulla and the central gray matter of cervical spinal cord that showed the “black butterfly” silhouette. Cerebral angiography revealed DAVFs draining into anterior and posterior spinal veins. Dark signals on T2*WI and SWI were presumed to be hemorrhages, which were probably caused by prolonged venous congestion. Identifying this “black butterfly” sign can facilitate the diagnosis of DAVF, differentiating DAVF from other spinal cord diseases such as demyelinating lesions and neoplasms.

First-Pass Contrast-Enhanced MR Angiography in Evaluation of Treated Spinal Arteriovenous Fistulas: Is Catheter Angiography Necessary?

Catheter angiography is typically used for follow-up of treated spinal AVFs. The purpose of this study was to determine the diagnostic performance and utility of first-pass contrast-enhanced MRA in the posttreatment evaluation of spinal AVFs compared with DSA. A retrospective review was performed of all patients at our tertiary referral hospital (from January 2000 to April 2015) who underwent spine MR imaging, first-pass contrast-enhanced MRA, and DSA after surgical and/or endovascular treatment of a spinal AVF. Presence of recurrent or residual fistula on MRA, including vertebral level of the recurrent/residual fistula, was evaluated by 2 experienced neuroradiologists blinded to DSA findings. Posttreatment conventional MR imaging findings were also evaluated, including presence of intramedullary T2 hyperintensity, perimedullary serpentine flow voids, and cord enhancement. The performance of MRA and MR imaging findings for diagnosis of recurrent/residual fistula was determined by using DSA as the criterion standard. In total, 28 posttreatment paired MR imaging/MRA and DSA studies were evaluated in 22 patients with prior spinal AVF and 1 patient with intracranial AVF with prior cervical perimedullary venous drainage. Six image sets of 5 patients demonstrated recurrent/residual disease at DSA. MRA correctly identified all cases with recurrent/residual disease with 1 false-positive (sensitivity, 100%; specificity 95%; P < .001), with correct localization in all cases without interobserver disagreement. Conventional MR imaging parameters were not significantly associated with recurrent/residual spinal AVF. First-pass MRA demonstrates high sensitivity and specificity for identifying recurrent/residual spinal AVFs and may potentially substitute for DSA in the posttreatment follow-up of patients with spinal AVFs.

A 75-year-old man with treatable progressive quadriparesis: answer

MRI showed diffuse cervical cord swelling and enlarged anterior spinal medullary veins. These abnormalities were suggestive of intracranial dural arterio-venous fistula (DAVF) with perimedullary venous drainage, confirmed by cerebral angiography. The fistula was fed by the middle meningeal artery and the left superior cerebellar artery (Fig. 1). Embolization of the middle meningeal artery using Onyx (ev3 Endovascular, Plymouth, MN, USA) unfortunately failed. Instead transarterial embolization of the left cerebellar artery was achieved using Histoacryl (TissueSeal, Ann Arbor, MI, USA). After 1 year, the patient could comfortably walk without a mobility device. MRI and brain angiography showed disappearance of the spinal cord swelling and of the DAVF (Fig. 2). Intracranial DAVF type V result from an abnormal communication between intracranial meningeal arteries and spinal perimedullary veins [1]. The arterialized spinal veins lead to congestive edema and subsequent ischemia of the spinal cord, causing myelopathy [2]. Various etiologies are postulated, including cerebral vein thrombosis, head trauma, and increased systemic thrombotic activity [3]. MRI findings are signal abnormalities of the spinal cord, enlarged perimedullary vessels, and cord enlargement [4]. An accurate diagnosis is established by cerebral angiography, and not by spinal angiography. First line of treatment is endovascular obliteration of the DAVF and the predictive factor

Normal Venous Phase Documented during Angiography in Patients with Spinal Vascular Malformations: Incidence and Clinical Implications.

A key angiographic sign observed in patients with spinal vascular malformations is the absence of a normal venous phase. While this finding alone is often believed to rule out a lesion impacting the perimedullary venous drainage, the observation of a venous phase in several patients with vascular malformations led us to reconsider the validity of that sign. Eighty-one patients with 6 spinal arteriovenous malformations, 16 perimedullary arteriovenous fistulas, 61 spinal epidural or dural AVFs, and 1 paravertebral AVF (2 patients had multiple lesions) were reviewed. The venous phase was defined as normal, absent, or indeterminate. The venous phase timing was analyzed in patients with spinal dural or epidural AVFs. The existence of a venous phase could not be determined for technical reasons in 23 patients. A venous phase was documented in 25 of 58 patients (43%), including 16 of 49 vascular malformations (40.0%) with perimedullary venous drainage. Twelve of the 30 patients (40.0%) with dural or epidural AVFs had a normal venous phase, appearing, on average, 10.1 seconds and best visualized 15.0 seconds after opacification of the artery of Adamkiewicz. A normal venous phase was observed in 43% of patients with spinal vascular malformations, and within an acceptable delay (<18 seconds) in 40% of slow-flow AVFs. While it remains an important angiographic sign, the observation of a normal venous phase cannot be used to exclude the presence of a vascular malformation or justify interrupting a diagnostic spinal angiogram.

Unilateral contrast-enhancing pontomedullary lesion due to an intracranial dural arteriovenous fistula with perimedullary spinal venous drainage: the exception that proves the rule

A large spectrum of possible diagnoses must be taken into consideration when a contrast-enhancing lesion of the pontomedullary region is found on MRI. Among these diagnoses are neoplastic, inflammatory, and infectious, as well as vascular pathologies. The authors report a rare case of an intracranial dural arteriovenous fistula (DAVF) with perimedullary spinal venous drainage (Cognard Type V) that initially presented as a unilateral contrast-enhancing pontomedullary lesion mimicking a brainstem neoplasm in a 76-year-old man. Following occlusion of the DAVF by transarterial embolization that resulted in clinical and radiological improvement, the fistula recurred 10 months later and was finally cured by a combined endovascularand surgical approach that resulted in complete occlusion. Clinical symptoms and MRI findings gradually improved following this treatment. A literature review on the MRI findings of Cognard Type V DAVF was performed. Centrally located medullary or pontomedullary edema represents the typical imaging finding, while unilateral edema as seen in the authors' patient is exceptionally rare. The hallmark imaging finding suggestive of DAVF consisting of perimedullary engorged vessels may not always be present or may only be very subtly visible. Therefore, the authors suggest performing contrast-enhanced MR angiography or even digital subtraction angiography in the presence of an unclear edematous brainstem lesion before scheduling stereotactic biopsy.

Lumbar spinal epidural arteriovenous fistula with perimedullary venous drainage after endoscopic lumbar surgery.

Spinal epidural arteriovenous fistulas (AVFs) with perimedullary venous drainage are rare. This report describes a case of lumbar epidural AVF in a patient with a history of endoscopic lumbar discectomy at the same level 8 years prior to presenting with progressive myelopathy secondary to retrograde venous reflux into the perimedullary vein. A 69-year-old man presented with progressive lower extremity weakness and sensory disturbance and loss of sphincter control 8 years after endoscopic lumbar discectomy for a disc herniation at L4-5 level. Magnetic resonance imaging showed spinal cord edema and dilated intradural perimedullary vessels. Spinal angiography revealed an epidural AVF at the site of the previous endoscopic lumbar surgery with intradural perimedullary venous drainage. The fistula was successfully occluded via endovascular transarterial embolization, and the patient had stabilization of his neurological deficits. Lumbar spinal epidural AVFs, especially those associated with iatrogenic trauma, are rare. Endoscopic surgical procedure can occlude the epidural venous plexus and disturb venous drainage, thereby inducing local venous hypertension and leading to epidural AVF with perimedullary venous drainage. This type of pathology should be considered within the differential diagnosis of delayed neurological deterioration after spinal surgery.

Risk Factors of Hematomyelia Recurrence and Clinical Outcome in Children with Intradural Spinal Cord Arteriovenous Malformations

Few published data are available concerning the risk of re-bleeding of spinal cord AVM after an hematomyelia and concerning the long-term clinical outcome. Our aim was to assess the risk of recurrence and long-term clinical outcome after hematomyelia in children with spinal cord AVMs. This single-center retrospective study reviewed the clinical and radiologic data of 28 children younger than 18 years of age with arteriovenous malformation who had experienced at least 1 episode of hematomyelia between 1988 and 2012. Long-term clinical outcome was assessed by the American Spinal Injury Association Impairment Scale, and radiologic review included MR imaging and angioarchitecture on angiography (blinded to clinical information) before treatment and at recurrence. Sixteen children (57%) experienced 1 episode of hematomyelia, while 12 children (43%) experienced recurrence. Girls and boys were equally affected (sex ratio, 1:1), and mean clinical follow-up was 5.7 ± 4.4 years. The risk of recurrence was higher for AVMs of the cervical and upper thoracic spine, 12 (100%) versus 11 (69%) (P = .01). A high American Spinal Injury Association scale score at last follow-up was reported for 11 children (39%), and the risk of recurrence tended to be associated with poorer functional prognosis (7 [64%] versus 5 [29%], P = .07). At the time of recurrence, perimedullary venous drainage was the main factor associated with recurrence (P = .002). Occlusion rate ≥50% was associated with a decreased risk of recurrence (P = .047). In the present series, cervical and upper thoracic spinal cord AVMs and microarchitecture were predictive of the risk of hematomyelia recurrence. Perimedullary venous drainage was one of the main parameters associated with recurrence. Functional prognosis was better in patients with a single episode of hematomyelia.

Fistule durale intracrânienne à drainage veineux périmédullaire : considérations anatomiques, cliniques et thérapeutiques à propos d’un cas, et revue de la littérature

Intracranial dural arteriovenous fistulae with perimedullary venous drainage are unusual type of vascular brain malformations. Patients may present with a rapidly progressive ascending myelopathy associated with autonomic dysfunction, which can cause a misdiagnosis and delay the therapeutic management. These clinical signs must be quickly recognized to avoid a poor outcome. The authors report the case of a 60-year-old woman presenting with a progressive myelopathy due to a dural arteriovenous fistula with perimedullary venous drainage. The diagnosis was suspected on brain-spinal MRI and confirmed by brain arteriography visualizing the arteriovenous shunt in the middle segment of the superior petrous sinus. MRI showed edema in the medulla oblongata. The treatment was performed early by endovascular glue embolization of the arteriovenous shunt and of the origin of the vein. Brain arteriography and clinical follow-up, one month later, showed complete disappearance of the dural fistula and regression of clinical symptoms. MRI control showed the reduction of the brain stem edema. Because of the early pejorative prognosis of these kinds of fistulae, early diagnosis and treatment are needed.

Endovascular treatment for dural arteriovenous fistula at the foramen magnum: Report of five consecutive patients and experience with balloon-augmented transarterial Onyx injection

Foramen magnum dural arteriovenous fistulas (DAVF) with perimedullary venous drainage represent a small minority of intracranial DAVF, and only a number of small series with limited cases have been reported. The purpose of this retrospective study is to summarize experience of transarterial Onyx embolisation in the treatment of these lesions, with emphasis on the balloon-augmented technique. Five consecutive patients with DAVF at the foramen magnum were treated by transarterial embolisation using the Onyx system. Their symptoms included myelopathy (n=4) and SAH (n=1). Suppliers were from the vertebral artery (VA) (n=4), occipital artery (OA) (n=4), and ascending pharyngeal artery (APA) (n=2), with drainage to the perimedullary veins. After catheterization of the dilated supplier, the fistulous connections, proximal draining veins and appropriate distal segment of the feeders of these DAVF were transarterial embolized using Onyx-18. In three patients, balloon-augmented technique was used to assist embolisation. The technical feasibility of the procedure, angiographic results, and clinical outcome were evaluated. In every case, complete obliteration was achieved. Neither intraprocedural vessel rupture nor other procedure-related complications occurred. The results remained stable in all patients on follow-up angiograms (mean, 7.2 months). At the last clinical follow-up (mean, 17.6 months), two patients showed complete resolution of the initial symptoms, and three patients showed significant improvement. We found that Onyx embolisation is a feasible and safe alternative to open surgery in the treatment of selective DAVF at the foramen magnum. The balloon-augmented technique widens indications for transarterial Onyx packing of these lesions, and improved safety of the procedure.

Spinal Epidural Arteriovenous Fistulas With Unusual Manifestation of Sudden Onset of Severe Neurological Deficits: Case Report

Spinal epidural arteriovenous fistulas with perimedullary venous drainage cause venous hypertension, and usually manifest as slowly progressive myelopathy. We treated two patients presenting with sudden onset of severe neurological deficits. Moreover, in Case 1, the venous drainage was exclusively epidural and no perimedullary venous drainage was present. Angiographic findings of this patient were characterized by a slow-flow fistula with marked retention of the epidural venous drainage. Rapidly progressing thrombosis of the epidural venous plexus may have caused the sudden onset of the symptoms. In Case 2, hematomyelia may also be possibly associated with the sudden onset of the symptoms. Early diagnosis and treatment are essential to achieve favorable outcome in such cases because venous congestion results in irreversible venous infarction within a short period.

Tips and traps in spinal cord pathology

While reviewing major pathological conditions, the radiologist must learn to adapt his technique to the indication and look for multifocal lesions. In conditions involving malformation, transdural cord herniation and diastematomyelia may be discovered late. In vascular diseases, a dural arteriovenous fistula with perimedullary venous drainage is the most common vascular malformation and a source of diagnostic error. On discovering a medullary cavity, the radiologist needs to know when to discount focal distensions of the ependymal canal and how to detect tumoral syringomyelia. In the case of a tumour, he should know the characteristics of common tumours such as astrocytomas, ependymomas, haemangioblastomas and cavernomas. In inflammatory diseases, he should know when a brain examination is required. When faced with images appearing to show a tumour, he should consider the possibility of pseudotumours and in particular of granulomatoses.

Letter to the editor of Acta Neurochirurgica: Intracranial venous drainage of a lumbar spinal dural arteriovenous fistula

Dear Editor, We would like to report the findings of intracranial venous drainage of a spinal dural arteriovenous fistula (sDAVF). While intracranial dural arteriovenous fistulas have long been recognized to have spinal venous drainage with characteristic myelopathy, to the best of our knowledge, intracranial venous drainage of a spinal AVF has not been previously documented [2, 3]. A 73 year old man was discovered to have a L4 (sDAVF) with retrograde intracranial drainage to the deep venous system (Fig. 1). This lesion was found incidentally during aortic angiography for repair of an abdominal aneurysm endo-leak. The patient denied previous symptoms consistent with sDAVF including myelopathic changes, bowel or bladder incontinence, or sensory changes [7]. He further denied any sign or symptom related to the intracranial venous drainage. The patient was counseled to undergo treatment based upon the pattern of drainage but ultimately elected to forgo further evaluation and treatment. Intracranial dural arteriovenous fistulas are well known to have perimedullary spinal venous drainage and cause myelopathy [3, 4]. However, to our knowledge, retrograde intracranial drainage from a sDAVF of the lumbar spine has not been described before. A patient with a lumbar sDAVF and brainstem symptoms has been reported by Wu and coworkers, but the draining vein did not extend intracranially [8]. Another report by Hashimoto et al., found perimesencephalic hemorrhage in conjunction with a sDAVF [5]. In comparison, our patient was asymptomatic despite the high level of venous drainage. This was probably related to prevalent involvement of the anterior venous drainage of the cord (Fig. 1) with relative sparing of the usually more robust dorsal draining system. He was thus spared the symptoms consistent with congestion of this system [1, 3, 6]. It is possible that the fistula developed in the setting of abnormal vasculature of the radicular arteries due both to the aneurysm and its endovascular treatment. A. M. Burrows :G. Lanzino (*) Department of Neurologic Surgery, Mayo Clinic, 200 1st St SW, Rochester, MN 55901, USA e-mail: lanzino.giuseppe@mayo.edu