Spinal cord arteriovenous malformations in two patients with hereditary hemorrhagic telangiectasia

Acute thrombosis of a giant perimedullary arteriovenous fistula in a pediatric HHT patient

Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant hereditary disorder that results in arteriovenous malformations (AVMs) in the nose, mucocutaneous surfaces and visceral organs, including lung, brain, liver, bowel and rarely spinal cord. We describe a case of a young child with HHT who presented with acute paraparesis due to acute thrombosis of a spinal perimedullary arteriovenous fistula. Patient underwent coil embolization of spinal arteriovenous shunt with resolution of clinical symptoms. This case highlights the possibility of catastrophic complications in young children with HHT, the potential preventive role of screening for spinal AVMs in HHT and the importance of timely intervention.

Intracranial subarachnoid hemorrhage caused by an aneurysm at the thoracic spinal region: case report and literature review

Background: The most common cause of intracranial subarachnoid hemorrhage (SAH) is an intracranial aneurysm or other vascular lesion; however, spinal lesions have also been implicated. Furthermore, vascular lesions rarely occur in the thoracolumbar region. We herein presented a case of intracranial SAH caused by an isolated aneurysm in the thoracic spinal artery.Case presentation: A 79-year-old woman developed the sudden onset of headaches in the parietal and occipital regions followed by vomiting. Head computed tomography (CT) scans showed SAH in the basal cistern and around the parietal lobe cortex. Cerebral angiography detected no aneurysm or vascular malformation. Spinal CT on day 1 showed extensive SAH at the posterior surface of the spinal cord, which was the most prominent at the level of T9/10, and spinal angiography subsequently revealed an aneurysm fed by the T10 radicular artery. The aneurysm was resected by T8-10 laminectomy, and the patient recovered with no long-term neurological deficit.Conclusions: A literature review revealed 17 cases of intracranial SAH from thoracolumbar vascular lesions. Most cases resulted in poor functional outcomes, which occurred in the later phase of the disease and may have been avoided with earlier diagnoses and interventions. We suggest whole spine CT as a useful tool for rapid screening of this rare lesion, and is recommended when an initial survey for intracranial lesions does not detect any likely lesions. Furthermore, ventricular reflux on head CT may lead to an accurate diagnosis in the absence of spinal symptoms.

Clinical presentation and treatment paradigms in patients with hereditary hemorrhagic telangiectasia and spinal vascular malformations

Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant disorder that causes angiodysplasia and results in mucocutaneous telangiectasias and arteriovenous malformations of organs. Although central nervous system vascular malformations can occur anywhere along the neuraxis, spinal vascular malformations are rare. We present our experience with the presentation and management of spinal vascular malformations in patients with HHT. Of the more than 800 patients with the diagnosis of HHT screened at our institution from 1995 through 2017, four patients with spinal vascular malformations (age range 1 month-77 years; 2 male, 2 female) were identified, three of whom came to clinical attention after significant neurological deterioration from previously unknown malformations. A review of the literature including our patients demonstrated 29 total spinal arteriovenous fistulas (AVFs) in 28 HHT patients (69% male). The lesions were located predominantly in the thoracic spine (65.5%). Three lesions were not treated, 17 were treated with embolization, 6 were surgically resected, and 3 were treated with embolization and surgery. In 14 cases, the patients presented with hemorrhage of the AVF. Overall, 79% of patients achieved complete or near-complete occlusion, with 75% reporting improvement in neurological function. Discovery of spinal lesions often occurs after neurological decline because current screening protocols do not include evaluation of the patient for spinal lesions. Most patients benefit from intervention, which is tailored to the characteristics of the patient and their malformation. Given the often-severe neurological deficit encountered at presentation, we favor a protocol that screens HHT patients for spinal vascular malformations.

Cervical spine arteriovenous fistula associated with hereditary haemorrhagic telangiectasia

Reported is a case of a man aged 55 years who presented with progressive spastic paraparesis. Examination demonstrated multiple cutaneous telangiectases. Subsequent development of upper limb weakness, acute urinary retention and eventual respiratory compromise resulted in the requirement for intensive care unit admission and mechanical ventilation. MRI spine revealed diffuse T2 hyperintensity in the cervical cord with enhancement and cord expansion. Immunomodulatory therapy for a presumed diagnosis of transverse myelitis yielded no response, so a vascular aetiology was suspected. Spinal angiography demonstrated an arteriovenous fistula involving the upper cervical cord. Endovascular embolisation was successfully performed and a marked clinical improvement was achieved. Cervical arteriovenous fistulas can cause progressive myelopathy, subarachnoid haemorrhage and brainstem dysfunction. Management typically comprises endovascular embolisation or surgical interruption. A clinical diagnosis of hereditary haemorrhagic telangiectasia was also made in this case, and spinal arteriovenous fistula formation has been associated with this condition.

Spinal arteriovenous fistulae in patients with hereditary hemorrhagic telangiectasia: A case report and systematic review of the literature

BACKGROUND

Although rare, spinal arteriovenous malformations (AVMs) are thought to be more prevalent in the hereditary Hereditary Hemorrhagic Telangiectasia (HHT) population.

METHODS

We report a case of a spinal AVM in a 37-year-old female with HHT treated with endovascular embolization. In addition, we report findings from a systematic review of the literature on the clinical characteristics, angioarchitecture, and clinical outcomes of HHT patients with spinal AVMs.

RESULTS

The patient is a 37 year-old female with definite HHT who presented with a one-year history of progressive gait difficulty. The spinal fistula was incidentally detected on chest computed tomography (CT). Spinal angiography demonstrated a large perimedullary arteriovenous fistula was supplied by a posterolateral spinal artery. The fistula was treated with detachable coils. The patient made a complete neurological recovery. Our systematic review yielded 25 additional cases of spinal AVMs in HHT patients. All fistulae were perimedullary (100.0%). Treatments were described in 24 of the 26 lesions. Endovascular-only treatment was performed in 16 cases (66.6%) and surgical-only treatment was performed in five cases (20.8%). Complete or near-complete occlusion rates were 86.7% (13/15) for endovascular treated cases, 100.0% (4/4) for surgery and 66.6% (2/3) for combined treatments. Overall, 80.0% of patients (16/20) reported improvement in function following treatment, 100.0% (5/5) in the surgery group and 84.6% (11/13) reported improvement in the endovascular group.

CONCLUSIONS

Spinal fistulae in HHT patients are usually type IV perimedullary fistulae. Both endovascular and surgical treatments appeared to be effective in treating these lesions. However, it is clear that endovascular therapy has become the preferred treatment modality.

Pediatric perimedullary arteriovenous fistula of the conus medullaris supplied by the artery of Desproges-Gotteron

The cone artery, or artery of Desproges-Gotteron, is sometimes seen arising from the internal iliac artery. The authors describe a case of a symptomatic perimedullary arteriovenous fistula (AVF) of the conus medullaris in an 8-year-old boy who presented with a protracted history of urinary difficulty and severe sudden-onset right lumbosciatic pain that evolved to severe paraparesis with compromise of the sphincter muscles. The spinal AVF, which was supplied by the cone artery and a thoracic radiculomedullary artery that joined at the fistula site in a large partially thrombosed varix, was completely occluded with Onyx liquid embolic. The patient's clinical condition improved rapidly after embolization. As shown in this patient, urgent endovascular embolization of spinal AVFs can be very rewarding, even in patients with severe neurological presentation. The artery of Desproges-Gotteron appears to be a rare arterial variation. To the authors' knowledge, this is the first pediatric case of a conal AVF supplied by this artery.

Spinal arteriovenous fistulas in children with hereditary hemorrhagic telangiectasia

Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant angiodysplasia with high penetrance and variable expression. The manifestations of HHT are often age related, and spinal arteriovenous fistula (AVF) may be the initial presentation of HHT in young children. Because spinal AVFs are rarely reported, however, screening is not incorporated into current clinical recommendations for the treatment of patients with HHT. The authors describe 2 cases of children younger than 2 years of age with acute neurological deterioration in the context of a spinal AVF and in whom HHT was subsequently diagnosed. One patient presented with intraventricular and subarachnoid hemorrhage and the other with acute thrombosis of an intramedullary varix. These cases highlight the potential for significant neurological morbidity from a symptomatic AVF in very young children with HHT. Given the lack of data regarding the true incidence and natural history of these lesions, these cases raise the question of whether spinal cord imaging should be incorporated into screening recommendations for patients with HHT.

Pediatric high-flow, cervical spinal, macro-arteriovenous fistula, treated with the endovascular cotton candy glue injection technique

A 3-year-old boy presented to our hospital with progressive neurological deficits. Spinal magnetic resonance imaging (MRI) revealed a perimedullary macro-arteriovenous fistula (PMAVF) resulting in a large venous pouch within the parenchyma of the lower cervical spinal cord. Transarterial varix embolization of the fistula from the venous side was performed using N-butyl cyanoacrylate with tantalum powder. Postembolization angiography confirmed obliteration of the fistula, and MRI revealed thrombosis and reduction in size of the venous component. The patient's clinical symptoms were reduced dramatically following the intervention, and no neurological complications occurred due to the treatment. The prognosis of spinal PMAVF depends primarily on the presence of medullar signs and symptoms and on time to treatment. The volume of the venous pouch after the intervention was markedly reduced, and complete clinical recovery was obtained. Urgent endovascular intervention, as seen in this case, is considered first-line therapy and aims to decrease the risk of neurological sequela.

A novel association between RASA1 mutations and spinal arteriovenous anomalies

BACKGROUND AND PURPOSE

CM-AVM is a recently recognized autosomal dominant disorder associated with mutations in RASA1. Arteriovenous lesions have been reported in the brain, limbs, and the face in 18.5% of patients. We report a novel association between RASA1 mutations and spinal arteriovenous anomalies.

MATERIALS AND METHODS

In a collaborative study, 5 index patients (2 females, 3 males) with spinal AVMs or AVFs and cutaneous multifocal capillary lesions were investigated for the RASA1 gene mutation.

RESULTS

All 5 patients were found to have RASA1 mutation (2 de novo, 3 familial), and all had multifocal capillary malformations at birth. Neurologic deficits developed at ages ranging from infancy to early adulthood. All spinal anomalies (2 AVMs at the conus, 1 AVM at the lumbosacral junction, and 1 cervical and 1 cervicothoracic AVF) were complex, extensive, and fast-flow lesions. All patients required treatment based on the clinical and/or radiologic appearance of the lesions.

CONCLUSIONS

To our knowledge, an association of RASA1 mutation and spinal AVM/AVF has not been described. MR imaging screening of patients with characteristic CMs and neurologic symptoms presenting at a young age may be useful in detecting the presence of fast-flow intracranial or intraspinal arteriovenous anomalies before potentially significant neurologic insult has occurred.

Acute paraplegia due to spinal arteriovenous fistula in two patients with hereditary hemorrhagic telangiectasia

Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant disorder characterized by recurrent epistaxis, cutaneous telangiectasia, and visceral arteriovenous malformations (AVM). Of these, spinal AVM is a rare manifestation that concerns mainly children. In this report, we describe two cases of spinal AVM revealed by acute paraparesis due to subarachnoid hemorrhage in children with HHT and reviewed the literature on spinal arteriovenous malformations in HHT. In most of the cases reported, the clinical presentation was acute in the pediatric population and insidious during adulthood. The prognosis of spinal AVM mainly depends on the presence or not of medullar signs and symptoms and on the delay before treatment. In conclusion, any child with a family history of HHT should be considered at risk for spinal AVM in order to improve management of such complications and to decrease the risk of neurological sequellae.

Hereditary hemorrhagic telangiectasia: from epistaxis to life-threatening GI bleeding

Hereditary hemorrhagic telangiectasia (HHT) is a rare inherited disorder characterized by widespread mucosal, dermal, and visceral telangiectasias, which can appear as red spots on the lips, tongue, fingers, nose, or intestines. Recurrent epistaxis is the universal presentation, but almost any organ can be affected. Gastrointestinal (usually stomach and small bowel), oral, and urogenital sites are the most common areas affected, whereas pulmonary arteriovenous fistulae can be the most catastrophic. This disorder can present at age 10, and if present, appears in most people by age 21. Gastrointestinal manifestations can cause minor-to-life-threatening bleeding and can lead to the need for liver transplantation. Therapy for HHT includes laser and Argon treatments, embolization, hormones, and surgery. Family members should be screened to provide early recognition and treatment. Gastroenterology nurses should be aware of this rare but potentially fatal disorder as it can be diagnosed or ruled out in the endoscopy suite.

Diagnosis and endovascular treatment of pediatric spinal arteriovenous shunts

Spinal arteriovenous shunts (SAVSs) are rarely diagnosed in infants and children, but they are important clinically because morbidity can be significant. Although these lesions do not form a distinct pathologic group separate from the SAVSs seen in older patients, experience with these malformations in the pediatric population has led to the identification of several important features that are characteristic of this group of SAVSs. Association with genetic abnormalities, heritable (hereditary hemorrhagic telangiectasia) and nonheritable somatic (spinal arteriovenous metameric syndrome or Cobb syndrome), is relatively common and likely underrecognized. Male predominance is more pronounced than in the adult population. Hemorrhagic presentation is more frequent than in adults, except in extremely young children. The natural history seems to be better than previously thought, with early rehemorrhage uncommon. Despite early presentation and severe symptoms, these lesions are frequently amenable to endovascular treatment, often with anatomic cure achieved and with improvement or stabilization of symptoms after partial targeted treatment.

Spinal arteriovenous shunts presenting as intracranial subarachnoid haemorrhage

Background

In approximately 5% of patients with intracranial subarachnoid haemorrhage (SAH), the cause is another than a ruptured aneurysm or perimesencephalic haemorrhage. One of these causes is a spinal arteriovenous shunt (SAVS). The aim of this study was to investigate the characteristics of patients with SAVS who present with intracranial SAH without symptoms and signs suggesting a spinal cause.

Methods

We systematically reviewed the literature and searched the SAH database of the University Medical Center Utrecht, The Netherlands, for patients with SAVS presenting with intracranial SAH and studied the characteristics of patients with SAVS whose clinical presentation mimicked intracranial SAH caused by rupture of a saccular aneurysm.

Results

Thirty-five patients were identified after a review of the literature. In our SAH database, comprising 2142 patients included in the period 1985–2004, we found one patient (0.05%, 95 % CI 0.006–0.3%). SAH due to SAVS occurred at any age (4–72 years). The SAVS was located at the craniocervical junction in 14 patients, at the cervical level in 11, and at the thoracolumbar level in the remaining 11 patients. The majority of patients (n = 26, 72%) had no disabling deficits at discharge or follow-up.

Conclusion

Rupture of a SAVS presenting as intracranial SAH is rare and can occur at any age. The SAVS can be located not only at the craniocervical junction or cervical level but also in the thoracolumbar region. Most patients with SAVS presenting as intracranial SAH have a good recovery.

Spinal arteriovenous shunts presenting before 2 years of age: analysis of 13 cases

BACKGROUND AND PURPOSE

A minority of patients with spinal arteriovenous malformations (SAVM) are symptomatic as neonates or infants. We analyzed the clinical and anatomic factors associated with this early presentation, and reviewed our experience in treating patients with these lesions.

METHODS

A retrospective review of clinical records and imaging studies was performed for patients with SAVM who presented at less than 2 years of age and who were examined by the diagnostic and interventional neuroradiology service at our institution. Clinical, imaging and treatment data had been entered prospectively into a department database.

RESULTS

Thirteen patients were identified that had SAVMs that were either diagnosed or that became symptomatic before 2 years of age (nine boys, four girls). These represented 13% of the SAVM seen during the same period of time. The mean age at presentation was 6.9+/-6.4 months. Of the 13 patients, 11 had neurologic symptoms attributable to the spinal lesion. The presentation was nonhemorrhagic in ten patients and associated with hemorrhage in three. Ten lesions were fistulas [spinal cord arteriovenous fistulas (SCAVFs)] (77%); two were of the nidus type of malformation. There were syndromic associations in eight patients: hereditary hemorrhagic telangectasia (HHT) in six patients, all but one of these lesions were intradural high-flow perimedullary SCAVFs (46% of overall SAVM and 56% of SCAVF), and spinal arteriovenous metameric syndrome in two patients. One patient had Hirschprung's anomaly. Eight patients underwent endovascular treatment alone, one had surgery and embolization, and four were not treated. In all patients undergoing embolization, n-butyl cyanoacrylate liquid adhesive was used. Of those patients who underwent endovascular treatment, the lesion was completely obliterated in 7 and a 90% reduction in nidal size was achieved in the remaining 2. There was one treatment complication (infection) which resolved with medical therapy. No procedure-related permanent morbidity or mortality was seen. Follow-up data were available (mean 31.4 months) in ten patients (nine treated). All treated patients were either stable or improved, with none showing further deterioration following treatment.

CONCLUSION

Factors associated with early presentation in neonates and infants with spinal arteriovenous shunts include the presence of high-flow, solitary fistulas and HHT. Specifically, the presence of SCAVF in a child less than 2 years of age is highly suggestive of HHT. Despite the aggressive nature of these lesions, many are amenable to endovascular treatment, and this is associated with a favorable posttreatment course in most cases.

Spinal Cord Intradural Arteriovenous Fistulae: Anatomic, Clinical, and Therapeutic Considerations in a Series of 32 Consecutive Patients Seen between 1981 and 2000 with Emphasis on Endovascular Therapy

OBJECTIVE:

To review our series of intradural spinal cord arteriovenous fistulas (SCAVFs), analyzing symptoms and related angioarchitecture, and to study the morphological and clinical results of embolization.

METHODS:

Thirty-two SCAVFs (in 22 adults and 10 children) were treated between 1981 and 2000. These lesions were classified as microarteriovenous fistulas (mAVFs) or macroarteriovenous fistulas (MAVFs) according to shunt morphology. Location, architecture, presenting symptoms, and age group were detailed. The selection of patients for endovascular versus surgical treatments was analyzed, as were the anatomic and clinical results obtained by embolization with n-butylcyanoacrylate. Clinical status was evaluated according to the Karnofsky Performance Scale score.

RESULTS:

Ten SCAVFs were found in the pediatric population (four mAVFs and six MAVFs). All four mAVFs presented with acute symptoms. Three mAVFs (two cervical and one thoracic) presented hematomyelia; in one patient with a thoracic AVF, subarachnoid hemorrhage was suspected. All six MAVFs were located in the thoracolumbar cord (five associated with hereditary hemorrhagic telangiectasias). Four of the six MAVFs presented with hemorrhage. In the adult population, there were 21 mAVFS (95%) and one MAVF (5%). Only two mAVFs were found in the cervical cord, all other shunts affecting the thoracolumbar region. Hemorrhage was present in 6 of the 22 cases seen in adults (27%). The symptoms of SCAVFs did not differ from those found in spinal cord arteriovenous shunts of nidus type. Pial venous reflux and congestion were the most frequently encountered features in both the adult and pediatric groups. Arterial aneurysms (different from false aneurysms) were not found in association with hemorrhagic presentation of SCAVFs. Mean follow-up in our series was 3.3 years. Of the MAVFs, 86% were embolized, with 67% cured. The others had more than 75% occlusion. All patients followed up improved significantly. Of the mAVFs, 48% were treated endovascularly. Successful embolization was performed in 75% of patients. One patient was not embolized because of vasospasm, whereas 67% percent of mAVFs were completely occluded, 22% were more than 90% occluded, and 11% were 75% occluded. Complementary surgery was deemed unnecessary. All patients with mAVFs improved significantly at follow-up. Transient complications occurred in 22% of all patients, with no permanent morbidity or mortality. No patient bled or rebled after embolization. Thirty-six percent of mAVFs were operated on because of anticipated technical difficulties for endovascular approach or distal localization of the shunt.

CONCLUSION:

Endovascular treatment of SCAVFs stabilizes, normalizes, or improves neurological symptoms in all patients at long-term follow-up, with no bleeds or rebleeds. Embolization of SCAVFs with glue is a safe treatment that compares favorably with other approaches and significantly improves the poor natural history of the disease.

Manifestations of hereditary hemorrhagic telangiectasia in children and adolescents

The medical literature provides little information on manifestations of hereditary hemorrhagic telangiectasia (HHT) in children. The presented investigation was initiated to analyze early presenting symptoms in HHT, which should help to make the diagnosis at a young age and thus prevent potential complications from occult visceral arteriovenous malformations (AVM), which have commonly been described in HHT. A series of 15 children and adolescents with a suspicious diagnosis of HHT were examined clinically for typical signs and symptoms of the disorder. If the diagnosis of HHT seemed to be likely, recommendations for non-invasive screening procedures were given. Screening was directed at the detection of occult visceral AVMs. Main outcome measures were the definition of principal signs of HHT in children and adolescents. Family history was positive for HHT in 13 persons. The principal sign of recurrent epistaxis was present in 10/15 individuals and the earliest age of onset with regard to epistaxis was 4 years. Cutaneous vascular lesions were present in 5/15 patients. Screening for AVMs was performed in six individuals and revealed vascular lesions of the brain in two patients and vascular lesions of the lung in two patients. Gastrointestinal hemorrhages were present in one infant. Based on these findings, diagnosis of HHT seemed likely in ten individuals and unlikely in five individuals. Signs and symptoms of HHT in children and adolescents may be discrete, but are detectable at an earlier age than previously thought. Clinical examinations in children from HHT families may help identify candidates who will benefit from molecular genetic testing or screening imaging studies.

Metachronous Multiplicity of Spinal Cord Arteriovenous Fistula and Spinal Dural AVF in a Patient with Hereditary Haemorrhagic Telangiectasia

SUMMARY

HHT (Hereditary Haemorrhagic Telangiectasia or Rendu Osler Weber disease) is a known autosomal dominant dysplasia. The first clinical presentation of HHT in a child may be a cerebral or spinal AVM. We present the case of a young boy with HHT who had a previous spinal cord AVF treated by surgical obliteration and then presented with a spinal dural AVF nine months later. This patient had surgical obliteration of a spinal cord perimedullary AVF and subsequently developed a new spinal dural AVF at a different level. The diagnosis was made by spinal MR imaging and spinal angiography.

Giant spinal perimedullary fistula in hereditary haemorrhagic telangiectasia: diagnosis, endovascular treatment and review of the literature

Hereditary hemorrhagic telangiectasia (HHT, Rendu-Osler-Weber disease) is a vascular disorder with dominant autosomal transmission characterised usually by multiple mucocutaneous and visceral abnormalities. Neurological manifestations due to the primary involvement of spinal cord by vascular malformations are rare. We present a young man with HHT associated with a central nervous system arteriovenous malformation and a giant perimedullary fistula, that was manifested as progressive myelopathy. The diagnosis was made coupling magnetic resonance imaging to selective spinal arteriography. The therapeutic option was endovascular treatment by mechanically detachable coils which resulted in full exclusion of the fistula with full improvement of symptoms. During follow-up a stable clinical and morphological outcome was achieved. Clinical manifestations in HHT, with emphasis on neurological symptoms, are reviewed as well as the therapeutic options to deal with giant perimedullary fistula.

Embolization of spinal cord arteriovenous shunts: morphological and clinical follow-up and results--review of 69 consecutive cases

OBJECTIVE

We sought to analyze the results of embolization in patients with intradural spinal cord arteriovenous shunts.

METHODS

The clinical and radiological files of 69 of a population of 155 patients treated with embolization between 1981 and 1999 were reviewed retrospectively. The patients' clinical status was evaluated according to Karnofsky Performance Scale score. Twenty-one (14%) of 155 patients were treated surgically because they were thought to be poor candidates for embolization. Twenty-four (15%) of 155 patients were considered untreatable with surgery or embolization; in these patients, follow-up was proposed, but only 8 of them were followed appropriately and remained stable after the first consultation. Forty-one (26%) of 155 patients consulted our group, but no follow-up could be obtained. In 69 (45%) of 155 patients, comprising 20 children and 49 adults, endovascular treatment was performed with the patients under general anesthesia and without provocative tests, mainly with acrylic glue, in 99% of these patients.

RESULTS

The mean number of diagnostic and therapeutic sessions was 3.5 per patient, and the mean number of pure therapeutic sessions was 1.5 per patient. Follow-up ranged between 6 months and 18 years (mean, 5.6 yr). In 16% of patients, anatomic obliteration of spinal cord arteriovenous shunts was obtained. Embolization reduced more than 50% of the spinal cord arteriovenous shunts in 86% of cases. No recanalization was noted on follow-up angiograms. Good clinical outcomes were obtained in 83% of the patients: 15% of them were asymptomatic, 43% were improved, and 25% were stable. In 4% of patients, embolization failed to stabilize the disease. Transient deficits were seen after embolization in 14% of the patients, and permanent severe complications occurred in 4% of the patients (Karnofsky Performance Scale score <or=70). Mild worsening was seen in 9% of the patients (Karnofsky Performance Scale score, 80). No bleeding or rebleeding was seen after endovascular treatment was considered to have been completed.

CONCLUSION

This study proves that embolization with acrylic glue is a therapeutic option that compares favorably with surgery or embolization with other agents (particles, coils, or balloons). It offers stable long-term clinical results, despite not necessarily achieving total cure. Studies of larger series with longer follow-up are necessary to confirm these encouraging therapeutic data.

Spinal cord arteriovenous shunts: from imaging to management

Spinal cord arteriovenous shunts (SCAVSs) are either fistulas or niduses that can be separated in four different groups according to their localization and relationship to the dura. Paraspinal AVSs are located outside the spine and are responsible for neurological symptoms because of cord compression by ertatic veins, venous congestion or arterial steal. Epidural shunts are located in the epidural space and drain in epidural veins with secondary intradural congestion. Dural shunts are embedded in the dura, produce a cord venous myelopathy after draining through veins that either pierce the dura far from a nerve root or accompany a nerve root. Intradural shunts affect the cord, the roots or the filum. Additionally, they can be classified according to their potential relationships with genetics, vascular biological features and angiogenesis into genetic hereditary lesions (hereditary hemorrhagic telangiectasia), genetic non-hereditary lesions (multiple lesions with metameric links) and single lesions (AVMs or micro AVFs). MRI and MRA are able to visualise SCAVS early after the onset of clinical symptoms. The type of shunt and its localization may remain difficult to be precise. Angiography remains the gold standard for analysis of the anatomical, morphological and architectural features necessary for therapeutic decisions in both paediatric and adult populations. In our series, embolisation is chosen in first intention whatever the type of shunt responsible for the clinical symptoms and glue is preferably used. In paraspinal, dural or epidural arteriovenous shunts, the goal of treatment should be complete closure of the shunt. A complete cure by embolization is rather easily achieved in paraspinal lesions. Failure of endovascular therapy in dural or epidural shunts must bring the patient to surgery. The prognosis of most intradural shunts seems better than previously thought, even after haemorrhage. In intradural spinal cord arteriovenous shunts, embolisation targeted towards the portions of the malformation felt to be responsible for the symptoms (venous congestion) or pointing to the point of rupture (false aneurysms) of the malformation, allows restoration of a new hemodynamic equilibrium between the malformation and the cord itself. Such targeted treatment offers long-term stabilisation or improvement to patients suffering from SCAVSs and good protection against (re) haemorrhages, with an acceptable morbidity. Cure of the shunt is not imperative to obtain these satisfactory outcomes. The clinical results obtained by such management compare favourably with those obtained by neurosurgery.

Venous manifestations of spinal arteriovenous fistulas

Spinal dural AVFs, the most common type of spinal arteriovenous malformations, are symptomatic because of venous hypertension and congestion. This has been referred to as venous congestive myelopathy. The typical MRI findings that reflect venous congestive myelopathy include peripheral T2 hypointensity that outlines a T2 hyperintensity within a swollen spinal cord. Enlarged perimedullary vessels are typically present. Contrast-enhanced MRA has become instrumental in localizing the site of these fistulas. Spinal epidural AVFs and the perimedullary spinal cord AVFs may also present with a congestive myelopathy and have similar findings on MRI. Angiography remains the gold standard for characterization of the angioarchitecture of spinal vascular malformations. [figure: see text] Multidisciplinary treatment planning is mandatory and requires knowledge of the natural history of these vascular lesions.

Classification of Spinal Cord Arteriovenous Shunts: Proposal for a Reappraisal—The Bicêtre Experience with 155 Consecutive Patients Treated between 1981 and 1999

OBJECTIVE

Spinal cord arteriovenous shunts (SCAVSs) are currently classified according to their morphological features. Certain shunts cannot be fully integrated into the predetermined categories that are usually described, however. Can these classifications be reevaluated on the basis of recent anatomic, biological, and genetic advances?

METHODS

We reviewed the clinical and radiological files for 155 SCAVSs that were treated at Hôpital Bicêtre between 1981 and 1999. The lesions were examined with respect to their number (single or multiple), their primary architectural type (nidus or fistula), and their possible links with associated metameric lesions.

RESULTS

All SCAVSs were either arteriovenous malformations or fistulae, with the latter being either micro- or macrofistulae. All SCAVSs corresponded to three categories, i.e., genetic hereditary lesions (macrofistulae and hereditary hemorrhagic telangiectasia), genetic nonhereditary lesions (all of which were multiple lesions with metameric or myelomeric associations), and single lesions (which could represent incomplete presentations of one of the previous groups). Of the SCAVSs in our series, 81% were single lesions and 19% were multiple; among these, 59% were true intradural shunts with metameric features. Ten cases of Cobb syndrome, three cases of Klippel-Trenaunay syndrome, and two cases of Parkes-Weber syndrome, all with associated cord lesions, were observed. Nineteen percent of SCAVSs were fistulae; 23% of those were macrofistulae, of which 83% were related to Rendu-Osler-Weber disease.

CONCLUSION

It seems legitimate to propose a categorization that takes into consideration a primary malformation (nidus or fistula) that evolves with time and in which angioarchitectural changes occur. Recognition of the factors originally responsible for the shunt (e.g., genetic hereditary or genetic nonhereditary) allows a different classification of SCAVSs.