Double spinal dural arteriovenous fistulas: case report and review of the literature

Multiple Synchronous Spinal Dural Arteriovenous Fistulas: A Systematic Literature Review

BACKGROUND AND OBJECTIVES

Spinal dural arteriovenous fistulas (SDAVFs) lead to progressive neurological decline with symptoms such as paraparesis, bowel and bladder dysfunction, and sensory disturbances because of impaired spinal cord venous drainage. This study aimed to systematically review the literature on multiple synchronous SDAVFs and present 2 cases from our institution.

METHODS

A comprehensive search was performed to identify all published cases of multiple synchronous SDAVFs. Overall, 23 patients with multiple synchronous SDAVFs were identified, including 21 from 19 articles and 2 from this study. The clinical presentation, lesion location, radiographic features, surgical treatment, and outcomes were analyzed in each patient.

RESULTS

All patients in this study were male, and the duration from symptom onset to diagnosis in many of these patients was longer than that previously reported. Previous studies suggested that multiple SDAVFs typically occurred within 3 or fewer vertebral levels. However, >50% of the examined patients had remote lesions separated by more than 3 vertebral levels. Patients with remote lesions had a significantly worse outcome (1/7 vs 8/11, 95% CI 0.001-0.998; P = .049).

CONCLUSION

Accurately locating fistulas before spinal angiography is critical for managing multiple remote SDAVFs. Considering the possibility of multiple remote SDAVFs, careful interpretation of imaging findings is essential for an accurate diagnosis and appropriate treatment planning.

De Novo Radicular Arteriovenous Fistula After Treatment of Spinal Arteriovenous Fistula: A Case Report and Literature Review

De novo spinal dural arteriovenous fistulas (AVFs) have been reported as metachronous AVFs However, metachronous spinal AVFs are extremely rare, and their pathogenesis remains uncertain. We report a case of de novo radicular AVF (RAVF) following treatment for spinal AVF at the craniocervical junction (CCJ). We also reviewed the literature and discussed the pathogenesis of metachronous spinal AVF. A 64-year-old male patient diagnosed with spinal AVF at the CCJ supplied from the right C1 segmental artery was treated with Onyx-18 (eV3 Inc, CA, USA) trans-arterial embolization, resulting in partial occlusion. Angiography showed a slight residual shunt two weeks after the embolization without another shunt lesion. A five-year follow-up spinal angiography showed de novo RAVF at the C4 level and complete occlusion of the first AVF. The second AVF was not treated because it was asymptomatic, and the patient remained asymptomatic. De novo RAVF was found to develop five years after the embolization of a CCJ-spinal AVF in a patient. This is the first case of de novo RAVF post-treatment of a spinal AVF. This case demonstrated that RAVF could develop as an acquired disease.

Long-term outcomes and prognostic factors in patients with treated spinal dural arteriovenous fistulas: a prospective cohort study

OBJECTIVE

To define the pattern of long-term clinical outcomes and prognostic factors in patients with spinal dural arteriovenous fistulas (SDAVFs).

DESGIN

Prospective cohort study based on constantly recruiting patients with SDAVFs in two medical centres in China.

SETTING

Patients with SDAVFs were recruited consecutively between March 2013 and December 2014 in two referral centres.

PARTICIPANTS

A prospective cohort of 94 patients with SDAVFs was included in this study, and 86 patients (mean age 53.0 years, 71 men) completed the study. Patients who had previously undergone endovascular or neurosurgical treatment or had neurological dysfunction caused by other diseases or refused treatment were excluded.

INTERVENTIONS

All patients underwent neurosurgery or endovascular embolisation. These patients were evaluated with the modified Aminoff and Logue's Scale (mALS) 1 day before and 3, 6, 12 and 72 months after treatments.

RESULTS

The duration of symptoms ranged from 0.5 to 66 months (average 12.8 months). The location of SDAVFs was as follows: 33.7% above T7, 50.0% between/include T7 and T12% and 16.3% below T12. 75 patients (87.2%) underwent neurosurgical treatment, and 9 patients (10.5%) underwent endovascular treatment. 58 patients (67.4%) exhibited an improvement in mALS of one point or greater at 72 months. Patients with less disability were more likely to improve at 72 months (p<0.05). 48 patients (55.8%) showed deterioration at 72 months compared with 12 months. 61% of the patients suffered numbness, and 22% had pain before treatment. However, 81% of patients had numbness, and 28% had pain after treatment. This deterioration was related to 1-year mALS and age.

CONCLUSION

Nearly two-thirds of the patients experienced clinical improvement at 72 months, and preoperative (1 day before treatment) mALS was the strongest predictor of clinical improvement. However, 55.8% of patients showed deterioration after temporary recovery. All patients with SDAVFs should accept treatment as soon as possible.

Case of Cowden Syndrome with 15 Spinal Arteriovenous Fistulas

BACKGROUND

Spinal vascular malformations are rarely multiple: fewer than 50 observations have been documented so far, with a maximum of 4 coexisting lesions per patient, always restricted to a single vertebral region (e.g., cervical or thoracic).

CASE DESCRIPTION

We describe the case of a 61-year-old woman with Cowden syndrome with 15 spinal arteriovenous fistulas (AVFs) at the cervical, thoracic, and lumbar levels and an adrenal AVF. She was initially referred for reevaluation of an upper cervical spinal epidural spinal arteriovenous fistula diagnosed 6 years earlier. Her history included breast carcinoma, a malignant salivary gland tumor, and removal of multiple ovarian, thyroid, and gastric hamartomas. Computed tomography and magnetic resonance imaging confirmed the presence of a prominent cervical vascular lesion. Spinal digital subtraction angiography revealed the presence of 15 additional vascular anomalies.

CONCLUSIONS

This multiplicity of AVFs appears to result from a combination of various factors including local regional hemodynamic changes, growth factor-mediated alterations involving notably vascular endothelial growth factor pathways, and the prothrombotic state associated with abnormalities in blood vessel structure.

True metachronous multiple spinal dural arteriovenous fistulas: case report and review of the literature

Spinal dural arteriovenous fistulas (DAVFs) are the most common type of spinal vascular disorders. Multiple spinal DAVFs are very rare, and the majority of them appear synchronously. True metachronous multiple spinal DAVFs occur even more rarely. We report a case of true metachronous multiple spinal DAVFs. A 61-year-old male presented with progressive paraparesis. Spinal MRI showed extensive edema of the spinal cord from T5 to the conus and prominent vascular flow voids. MR angiography showed a left T10 DAVF. The fistula was treated surgically and the clinical symptoms gradually resolved. Recurrence of symptoms occurred 4 months after surgery. A second angiography showed a new fistula located at the right L1. The second fistula was treated surgically and the symptoms again gradually improved. Metachronous multiple spinal DAVF may present within 4 months of each other.

Multidisciplinary approach in the treatment of spinal dural arteriovenous fistula-results of endovascular and surgical treatment

BACKGROUND

The results of treatment for spinal dural arteriovenous fistula (SDAVF) have been controversial. The goal of this study was to compare results of endovascular and surgical treatments to contribute to determining an optimal treatment strategy.

METHODS

A retrospective analysis of the set of 24 SDAVF patients (11 in the endovascular and 13 in the surgical group) was performed. The clinical effect (using the modified Rankin scale [mRS]), the radicality, and the number of clinical recurrences as well as the impact of age, the level of impairment, and the duration of symptoms before the treatment were evaluated.

RESULTS

The average age was 60.1 ± 8.4 years. The median duration of symptoms before establishing a diagnosis was 12 (1-70) months. Clinical improvement was reported in 11 out of 24 (45.8%) patients (36.4% following embolization and 53.8% following surgery, p = 0.444). Radical performance was achieved in 47.4% of endovascular versus 92.9% of surgical procedures (p = 0.009). Clinical recurrence was reported in 35.3% of patients in the endovascular group, whereas no clinical recurrence was reported in the surgical group (p = 0.0133). The graphical residuum after 1 surgery out of 14 (7.1%) was cured early during the control angiography. Clinical improvement was reported 42.1% of patients with mRS ≤ 3 versus 60% of patients with mRS ≥ 4 and, in 57.1% of patients aged ≥ 60 versus in 30% of patients < 60 years (p > 0.05 in both cases). The impact of the duration of symptoms on the clinical results was not statistically significant.

CONCLUSIONS

The surgical treatment of SDAVF appeared to be a more efficient method in terms of the clinical effect, radicality, and lower recurrence rate in comparison with the endovascular treatment. No statistically significant dependence of the clinical result on age, deficit burden, or symptom duration was found.

Double spinal dural arteriovenous fistulas

BACKGROUND

Spinal dural arteriovenous fistulas (SDAVF) are usually solitary lesions. Synchronous and/or metachronous double SDAVF have rarely been reported in the literature. We report on three patients with double SDAVF and present our single center experience in the diagnostic and treatment management in these patients.

MATERIAL AND METHODS

We retrospectively revised our medical database for all patients who were diagnosed and treated in our center due to a SDAVF between 1990 and 2017. All data including demographics, clinical presentations, as well as radiological data were re-evaluated for this study.

RESULTS

Three (1.4%) of 209 consecutive patients with SDAVF presented double SDAVF with different arterial feeders and venous drainage patterns. All three patients were men. The mean age at time of diagnosis was 67.9 ± 10 years (median; 68, range: 53-82). Myelopathic symptoms were reported in all three cases. All three fistulas were located in the thoracolumbar region between T7 and L2. MRI/CE-MRA showed medullar T2-hyperintensity, intramedullary contrast-enhancement and dilatation of perimedullary veins in various extensions.

CONCLUSION

Double SDAVF are extremely rare and were found in 1.4% of patients in our series. The vast majority of the reported double SDAVF in the literature has been detected synchronously within an area of equal or less than three vertebral levels. Thus, whenever the SDAVF is identified, further injections of the fistula-zone neighbored segmental arteries might be recommended. However, due to the extremely low incidence of double SDAVF a complete spinal DSA is not indicated.

Clinical outcomes and prognostic factors in patients with spinal dural arteriovenous fistulas : a prospective cohort study in two Chinese centres

BACKGROUND

The short-term outcomes and prognostic factors of patients with spinal dural arteriovenous fistulas (SDAVFs) have not been defined in large cohorts.

OBJECTIVE

To define the short-term clinical outcomes and prognostic factors in patients with SDAVFs.

METHODS

A prospective cohort of 112 patients with SDAVFs were included consecutively in this study. The patients were serially evaluated with the modified Aminoff and Logue's Scale (mALS) one day before surgery and at 3 months, 6 months and 12 months after treatment. Univariate and multivariate analyses were performed to identify demographic, clinical and procedural factors related to favourable outcome.

RESULTS

A total of 94 patients (mean age 53.5 years, 78 were men) met the criteria and are included in the final analyses. Duration of symptom ranged from 0.5 to 66 months (average time period of 12.7 months). The location of SDAVFs was as follows: 31.6% above T7 level, 48.4% between T7 and T12 level (including T7 and T12) and 20.0% below T12 level. A total of 81 patients (86.2%) underwent neurosurgical treatment, 10 patients (10.6%) underwent endovascular treatment, and 3 patients (3.2%) underwent neurosurgical treatment after unsuccessful embolisation. A total of 78 patients demonstrated an improvement in mALS score of one point or greater at 12 months. Preoperative mALS score was associated with clinical improvement after adjusting for age, gender, duration of symptoms, location of fistula and treatment modality using unconditional logistic regression analysis (p<0.05).

CONCLUSION

Approximately four fifths of the patients experienced clinical improvement at 12 months and preoperative mALS was the strongest predictor of clinical improvement in the cohort.

Spinal dural arteriovenous fistulas: the most frequent vascular malformations of the spinal cord

Spinal dural arteriovenous fistulas are produced by direct communication between the arterial and venous systems of the spinal cord, causing hypertension in the latter with spinal cord dysfunction. It is a rare pathology with unknown etiology and non-specific clinical symptoms that usually results in a delayed diagnosis. Often radiologists are the first to guide the disease towards an adequate diagnosis. Characteristic findings can be seen through MR or MR angiography, and may even locate the fistula in a high percentage of cases, although the pathology must be confirmed by spinal angiography. There are two treatment modalities: endovascular and surgical therapy. Endovascular treatment has improved in recent years with the advantages of a less invasive approach and is therefore usually chosen as primary therapy. In this article we review the main clinical manifestations, imaging findings and treatment of this pathology.

Early description of synchronous double spinal vascular malformations by Łucja Frey in 1928

The Polish neurologist Łucja Frey (1889–1942) is principally remembered for her description of the auriculotemporal nerve (or Frey's) syndrome. She also reported a complex case of spinal cord vascular malformation in 1928, which included one of the earliest accurate anatomopathological depictions of a spinal arteriovenous malformation as well as the first known observation of double synchronous spinal cord vascular malformation.

An abbreviated translation of Frey's report is followed by a discussion of the place occupied by her contribution in the development of our current understanding of spinovascular disorders.

Concomitant origin of the anterior or posterior spinal artery with the feeder of a spinal dural arteriovenous fistula (SDAVF)

Background/objective

The concomitant origin of the anterior spinal artery (ASA) or the posterior spinal artery (PSA) from the feeder of a spinal dural arteriovenous fistula (SDAVF) is rare and the exact incidence is not known. We present our experience with the management of SDAVFs in such cases.

Methods

In 63 patients with SDAVF between 1993 and 2015, the feeder origin of the SDAVF was evaluated to determine whether it was concomitant with the origin of the ASA or PSA. Embolization was attempted when the patient did not want open surgery and an endovascular approach was regarded as safe and possible. The outcome of the procedure was evaluated as complete, partial, or no obliteration. The clinical outcome was evaluated by Aminoff–Logue (ALS) gait and micturition scale scores.

Results

Nine patients (14%) had a concomitant origin of the ASA or PSA with the feeder. There were two cervical, five thoracic, and two lumbar level SDAVFs. A concomitant origin of the feeder was identified with the ASA (n=7) and PSA (n=2). Embolization was performed in four patients and open surgery was performed in five. Embolization resulted in complete obliteration in three patients and partial obliteration in one. Using the ALS gait and micturition scale, the final outcome improved in six while three cases remained in an unchanged condition over 2–148 months.

Conclusions

The concomitant origin of the ASA or PSA with the feeder occurs occasionally. Complete obliteration of the fistula can be achieved either by embolization or open surgery. Embolization can be carefully performed in selected patients who are in a poor condition and do not want to undergo open surgery.

Spinal Dural Arteriovenous Fistula: A Review

Spinal dural arteriovenous fistula (SDAVF) is a rare disease, the etiology of which is not entirely clear. It is the most common vascular malformation of the spinal cord, comprising 60-80 % of the cases. The clinical presentation and imaging findings may be nonspecific and misleading, often mistaking it for other entities like demyelinating or degenerative diseases of the spine.This chapter describes the imaging findings, clinical signs, and symptoms of this disease and also the available treatment options according to the current literature.Angiography is still considered the gold standard for diagnosis; however, MRI/MRA is increasingly used as a screening tool. Modern endovascular techniques are becoming increasingly more effective in treating SDAVF offering a less invasive treatment option; however, they still lag behind surgical success rates which approach 100 %. The outcome of both treatment options is similar if complete obliteration of the fistula is obtained and depends mainly on the severity of neurological dysfunction before treatment.Heightened awareness by radiologists and clinicians to this rare entity is essential to make a timely diagnosis of this treatable disease. A multidisciplinary treatment approach is required in order to make appropriate treatment decisions.

Intramedullary hemorrhage from a thoracolumbar dural arteriovenous fistula

BACKGROUND CONTEXT

Spinal dural arteriovenous fistulas (AVFs) are acquired lesions presenting typically with neurologic deficits secondary to chronic congestive myelopathy. The low-flow and low-volume nature of these lesions makes hemorrhage very unlikely, and intramedullary hemorrhage caused by thoracolumbar dural AVFs is exceedingly rare.

PURPOSE

The purpose of this study was to report a case of intramedullary hemorrhage caused by a thoracolumbar dural AVF.

STUDY DESIGN/SETTING

The study design included a case report and review of literature.

METHODS

A case of intramedullary hemorrhage from a thoracolumbar dural AVF was reported, and the literature regarding hemorrhagic presentations of dural AVF was reviewed.

RESULTS

A 66-year-old woman presented with a sudden onset of abdominal pain, paraplegia, sensory loss below the costal margins, and urinary retention. Magnetic resonance imaging scan showed intramedullary hemorrhage with abnormal flow voids raising suspicion of an intramedullary AV malformation. However, subsequent selective spinal angiography demonstrated a spinal dural AVF fed by the T7 intercostal artery and a varix within the draining vein. Complete obliteration of the dural AVF and the varix was achieved via embolization. As far as we are aware, there are only two other similar cases in the literature. Literature review revealed that presentation of thoracolumbar dural AVFs with hemorrhage is frequently associated with accelerated venous flow and the presence of a venous varix.

CONCLUSIONS

Although very unusual, a spinal dural AVF may present with intramedullary hemorrhage, and hemorrhage in such conditions may be associated with an accelerated venous flow and the presence of a venous varix.

Spinal dural arteriovenous fistulas: outcome and prognostic factors

The aim of this study is to review the clinical outcome of patients treated for spinal dural arteriovenous malformations and investigate the presence of pretreatment indicators of outcome after short- and midterm follow-up. The authors retrospectively reviewed the records of 65 consecutive patients treated either surgically or endovascularly in 3 neurosurgery departments between 1989 and 2009. After treatment, 80% of patients reported improvement of at least 1 symptom. Motor symptoms improved more than sensory disorders, pain, or sphincter impairment. Spinal dural arteriovenous fistulas at the thoracic level, and in particular at the lower level, responded better than those in other spinal areas. Spinal dural arteriovenous fistula is a rare pathology with a malignant course that should be treated aggressively. This study appears to confirm that neurological status before treatment, anatomical location of the fistula, and symptoms at presentation are all factors that can predict outcome. Early diagnosis of spinal dural arteriovenous malformations in the lower thoracic area in patients with an Aminoff scale score < 3 was associated with the most favorable outcome.

Multiple spinal and cranial dural arteriovenous fistulas

Synchronous multiplicity of cranial and spinal dural arteriovenous fistulas (DAVFs) is known but uncommon. The authors report on a patient with the unusual finding of multiple cranial and multiple separate spinal DAVFs. The patient initially presented with vague visual symptoms in 2004. A cranial DAVF was identified along the left transverse sinus with cortical venous reflux and another DAVF was identified along the posterior part of the superior sagittal sinus with no cortical venous reflux. The first DAVF was treated both endovascularly and surgically and the second was left untreated. The follow-up angiogram showed multiple spinal DAVFs at the levels of C-1, C-2, and C-6 on the left side and at the C-3 level on the right side along with another cranial DAVF along the anterior part of the superior sagittal sinus with cortical venous reflux. A retrospective analysis of the digital subtraction angiogram and MR images suggested that the cervical spinal DAVFs were already present in 2004 (6 years previously). Multiple DAVFs, although rare, do exist and it is important to look for any evidence of their presence when evaluating patients with symptoms suggestive of arteriovenous fistulas.

Mirror-Image Spinal Dural Arteriovenous Fistulas at the Craniocervical Junction

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

Spinal dural arteriovenous (AV) fistulas are the most commonly encountered vascular malformation of the spinal cord and a treatable cause for progressive para- or tetraplegia. They most commonly affect elderly men and are classically found in the thoracolumbar region. The AV shunt is located inside the dura mater close to the spinal nerve root where the arterial blood from a radiculomeningeal artery enters a radicular vein. The increase in spinal venous pressure leads to decreased drainage of normal spinal veins, venous congestion, and the clinical findings of progressive myelopathy. On MR imaging, the combination of cord edema, perimedullary dilated vessels, and cord enhancement is characteristic. Therapy has to be aimed at occluding the shunting zone, either by superselective embolization with a liquid embolic agent or by a neurosurgical approach. Following occlusion of the fistula, the progression of the disease can be stopped and improvement of symptoms is typically observed.

Spinal dural arteriovenous fistula mimicking prostate hyperplasia

BACKGROUND

Initially described in 1926, spinal dural arteriovenous fistula remains diagnostically challenging. Presenting symptoms are often common complaints in general practice or the emergency department, such as leg weakness or numbness. One of the less recognized early features is that of sphincteric disturbance.

OBJECTIVES

To elucidate the underappreciated early feature of urinary sphincter disturbance in spinal arteriovenous fistula.

CASE REPORT

We report on 2 patients with early urinary symptoms that mimicked obstructive uropathy, both of whom sought medical attention on several occasions before the diagnosis was reached. The clinical and imaging findings of spinal dural fistula are discussed.

CONCLUSION

Atypical presentations of bladder dysfunction in addition to other neurologic complaints in the appropriate patient population should prompt spinal imaging to exclude a spinal dural fistula. Timely diagnosis and treatment can prevent the progression of spinal cord edema to infarction with paraparesis, and permanent bladder and bowel dysfunction.

Epidural Spinal Myelolipoma in a Dog

Epidural spinal myelolipoma was diagnosed in a 13-year-old, male Siberian husky that was referred for evaluation of progressive pelvic limb paresis and urinary incontinence. An epidural mass was detected by magnetic resonance imaging and computed tomography. The mass was removed and identified histopathologically as an epidural myelolipoma. Pelvic limb paresis improved after surgery, but urinary retention associated with neurological bladder dysfunction persisted.

Spinal epidural arteriovenous fistula with perimedullary drainage. Case report and pathomechanical considerations

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 with peri-medullary venous drainage: analysis of a series from a single centre and review of the literature]

INTRODUCTION

The optimal diagnosis and therapeutic managements of spinal dural arteriovenous fistulae, a rare disease, is discussed.

MATERIAL AND METHODS

We report a series of 10 patients seen in a 7-year period, treated by embolization.

RESULTS

There were 6 males and 4 females, with an average age of 58.4 years (range: 31 to 74 years). Diagnosis was made 2 days to 5 years (mean 15.3 months) after symptom onset with a high rate of incomplete or atypical clinical patterns (prolonged isolated sensory disorder, lumbo-sciatalgia, claudication, monoplegia), or sudden-onset deficit. In all cases, spinal MRI showed an intramedullary high-intensity signal on T2-weighted images but enlarged intradural vessels in only 70p.cent of cases. Angiography showed in all cases an arteriovenous fistula at the upper dorsal level (T1 to T7, 5 cases), lower dorsal (T8-T12, in 3 cases) and lumbar levels (2 cases). The fistula was successfully obliterated after initial embolization in 3 cases, but two (2 cases) or 3 procedures (2 cases) were sometimes required. The endovascular therapy failed in 3 cases.

CONCLUSION

In this series, the fistula was successfully obliterated in 70p.cent of patients. In the literature, fistula of 96.8p.cent to 97.9p.cent of patients were obliterated by surgery, which is a more invasive treatment. Embolization could be used as the first-line therapy, but incomplete obliteration requires rapid surgery. While the success of embolization is demonstrated, MRI and angiography must still be performed 6 months later.

Metachronous double spinal dural arteriovenous fistulas

✓ Spinal dural arteriovenous fistulas (DAVFs), the most common of spinal vascular malformations, are AVFs in the dura mater of the nerve root and/or adjacent spinal dura. These fistulas are most often solitary and are fed by a single radicular artery that primarily supplies the dura mater. Multiple spinal DAVFs are rarely reported in the literature. Those that have been documented have been synchronous in their presentation in that they were found during the same examination or were present at the initial examination but missed and only recognized at the second examination. The authors report the case of a patient with two spinal DAVFs occurring at different spinal levels at different points in time (metachronous).

Spinal dural arteriovenous fistula

PURPOSE OF REVIEW

To summarize clinical key points, diagnostic features, and results of imaging and therapy of spinal dural arteriovenous fistula (SDAVF).

RECENT FINDINGS

SDAVF accounts for 70% of spinal arteriovenous malformation with an annual incidence of 5-10 cases per million. At least 80% of patients are male, and more than 66% of patients are in the sixth and seventh decade of life indicating preponderance of gender and age. Thrombophilia is not a predisposing factor of disease. Clinical course is predominated by symptoms of congestive myelopathy, but subarachnoid hemorrhage may occur. Double SDAVF is a rare problem in the management of disease. Magnetic resonance imaging has replaced myelography as screening procedure. Contrast-enhanced magnetic resonance angiography and multislice computerized tomographic angiography may facilitate diagnostic procedure, however, spinal angiography is still required to confirm diagnosis. Treatment by permanent occlusion of fistula results in clinical improvement in 70% of cases. Microsurgical shunt interruption has proven secure and reliable. Endovascular shunt embolization has been established as a standardized procedure, but occlusion rates are still lower than in surgical treatment.

SUMMARY

Advances have been made in diagnosis and treatment of SDAVF, but the disease is still not completely understood.

Spinal dural arteriovenous fistula associated with a spinal perimedullary fistula: case report

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.

Spinal vascular malformations

Spinal vascular malformations are rare diseases that consist of true inborn cavernomas and arteriovenous malformations (including perimedullary fistulae, glomerular and juvenile AVMs) and presumably acquired dural arteriovenous fistulae. This review article gives an overview of the imaging features both on MRI and angiography, the differential diagnoses, the clinical symptomatology and the potential therapeutic approaches to these diseases. It is concluded that MRI is the diagnostic modality of first choice in suspected spinal vascular malformation and should be complemented by selective spinal angiography. Treatment in symptomatic patients offers an improvement in the prognosis, but should be performed in specialized centers. Patients with spinal cord cavernomas and perimedullary fistulae type I are surgical candidates. Dural arteriovenous fistulae can either be operated upon or can be treated by an endovascular approach, the former being a simple, quick and secure approach to obliterate the fistula, while the latter is technically demanding. In spinal arteriovenous malformations, the endovascular approach is the method of first choice; in selected cases, a combined therapy might be sensible.