Iterative Denoising Accelerated 3D FLAIR Sequence for Hydrops MR Imaging at 3T.

BACKGROUND AND PURPOSE: 3D FLAIR sequences have become the criterion standard for identifying endolymphatic hydrops, but scan time remains an important limitation to their widespread use. Our purpose was to evaluate the diagnostic performance and image quality of an accelerated 3D FLAIR sequence combined with an iterative denoising algorithm. MATERIALS AND METHODS: This was a retrospective study performed on 30 patients with clinical suspicion of endolymphatic hydrops who underwent 3T MR imaging 4 hours after gadolinium injection using two 3D FLAIR sequences. The first (conventional FLAIR) was accelerated with a conventional turbo factor of 187. The second was accelerated with an increased turbo factor of 263, resulting in a 33% scan time reduction (5 minutes 36 seconds versus 8 minutes 15 seconds, respectively). A sequence was reconstructed in-line immediately after the accelerated 3D FLAIR acquisition from the same raw data with iterative denoising (accelerated-FLAIR iterative denoising). The signal intensity ratio image quality score and endolymphatic hydrops diagnosis were evaluated. RESULTS: The mean signal intensity ratio for symptomatic and asymptomatic ears of accelerated-FLAIR iterative denoising was significantly higher than the mean SNR of conventional FLAIR (29.5 versus 19 and 25.9 versus 16.3, P < .001). Compared with the conventional FLAIR sequence, the image-quality score was higher with accelerated-FLAIR iterative denoising (mean image-quality score, 3.8 [SD, 0.4] versus 3.3 [SD, 0.6] for accelerated-FLAIR iterative denoising and conventional FLAIR, respectively, P = .003). There was no significant difference in the diagnosis of endolymphatic hydrops between the 2 sequences. Interreader agreement was good-to-excellent. CONCLUSIONS: The iterative denoising algorithm applied to an accelerated 3D FLAIR sequence for exploration of endolymphatic hydrops enabled significantly reducing the scan time without compromising image quality and diagnostic performance.

Pulsatile Tinnitus Due to Stenosis of the Marginal Sinus: Diagnosis and Endovascular Treatment.

BACKGROUND AND PURPOSE: Venous pulsatile tinnitus is a disabling condition mainly caused by a stenosis of the lateral sinus. Here, we aimed to report a novel cause of venous pulsatile tinnitus, stenosis of the marginal sinus. MATERIALS AND METHODS: We retrospectively analyzed patients with isolated venous pulsatile tinnitus for which the suspected cause was a stenosis of the marginal sinus, treated or not, between January 2017 and December 2020. Patient charts and imaging were systematically reviewed. All patients underwent noncontrast temporal bone CT and MR imaging. RESULTS: Eight patients (7 women; median age, 36 years) were included. Six patients (75%) were overweight, and 1 patient had idiopathic intracranial hypertension. All patients presented with a typical venous pulsatile tinnitus. The stenosis of the marginal sinus was detected using oblique reconstructions on postcontrast 3D MR imaging. There was no other pathologic finding except ipsilateral stenosis of the lateral sinus in 3 patients. Four patients underwent endovascular therapy with placement of a stent in the marginal sinus, leading to complete resolution of the pulsatile tinnitus for all of them. No complication occurred. Of note, the symptoms of intracranial hypertension also regressed after stent placement in that patient. CONCLUSIONS: Marginal sinus stenosis is a novel cause of venous pulsatile tinnitus, which can be easily detected on MR imaging. Marginal sinus stent placement is safe and efficient. We hypothesized that the marginal sinus stenosis pathophysiology is similar to that of lateral sinus stenosis, which is a common and well-known cause of venous pulsatile tinnitus, explaining the similar clinical presentation and endovascular management.

Unusual arterial thrombotic events in Covid-19 patients.

INTRODUCTION: COVID-19 infection is commonly complicated with pro-thrombotic state and endothelial dysfunction. While several studies reported a high incidence of venous thromboembolic events. The occurrence of arterial thromboses are yet rarely described and could be underestimated. OBJECTIVES: To describe the clinical and biological characteristics of COVID-19 patients presenting with an associated arterial thromboembolic event. MATERIAL AND METHODS: We performed a retrospective multicentric study in 3 centers between France and Italy. All patients with a confirmed SARS-CoV-2 infection and arterial thromboembolic events were included in the analysis. RESULTS: From March 8th to April 25th 2020, we identified 20 patients (24 events) with arterial thromboembolic events over 209 admitted patients (9.6%) with severe COVID-19 infection. Arterial thrombotic events included acute coronary occlusions (n = 9), stroke (n = 6), limb ischemia (n = 3), splenic infarcts (n = 3), aortic thrombosis (n = 2) and occlusive mesenteric ischemia (n = 1). At the time of the event, 10/20 (50%) of patients received thromboprohylaxis, 2/20 (10%) were receiving treatment dose anticoagulation and 5/20 (25%) were receiving antiplatelet therapy. CONCLUSION: Our observations suggest that serious arterial thrombotic events might occur in Covid-19 patients. However, the exact incidence of such events and the best way to prevent them yet remains to be investigated.

Large vessel stroke in six patients following SARS-CoV-2 infection: a retrospective case study series of acute thrombotic complications on stable underlying atherosclerotic disease.

BACKGROUND AND PURPOSE: Ischaemic stroke has been described in association with COVID-19. Several pathophysiological mechanisms have been suggested, i.e. prothrombotic state, cardiac injury etc. It was sought to assess the potential association between ischaemic stroke associated with SARS-CoV-2 infection and underlying atherosclerotic lesions. METHODS: A retrospective analysis of stroke related to large vessel occlusion was conducted amongst patients with SARS-CoV-2 infection and underlying mild atherosclerotic disease, between 19 March and 19 April 2020 in six different stroke centers in the Île-de France area, France. RESULTS: The median age was 52 years, median body mass index was 29.5 kg/m2 . All patients displayed previous vascular risk factors such as high blood pressure, diabetes, dyslipidemia or body mass index > 25. The delay between the first respiratory symptoms of COVID-19 and stroke was 11.5 days. At baseline, all had tandem occlusions, i.e. intracerebral and extracerebral thrombus assessed with computed tomography or magnetic resonance imaging. Cases displayed a large thrombus in the cervical carotid artery with underlying mild non-stenosing atheroma, after an etiological workup based on angio-computed tomography or magnetic resonance imaging and/or cervical echography. CONCLUSION: Our study should alert clinicians to scrutinize any new onset of ischaemic stroke during COVID-19 infection, mainly in patients with vascular risk factors or underlying atherosclerotic lesions.

MRI evaluation of the endolymphatic space in otosclerosis and correlation with clinical findings.

PURPOSE: The purpose of this study was to investigate the clinical features of ears with otosclerosis and their correlation with endolymphatic hydrops and blood-labyrinth barrier (BLB) impairment on 3T magnetic resonance imaging (MRI). MATERIALS AND METHODS: This was a single-center retrospective imaging study. Thirty-nine ears from 29 patients (17 men, 12 women; mean age 52±12 [SD] years; range 27-74 years) with non-operated otosclerosis were included. All patients underwent three-dimensional fluid attenuated inversion recovery (FLAIR) MRI sequences performed 4hours after the intravenous administration of a single dose of gadolinium-based contrast material. MRI examinations were analyzed by two radiologists for the presence of saccular hydrops (SH) and BLB impairment. Results of MRI examinations were compared with clinical findings, hearing levels and extent of otosclerotic lesions based on high-resolution computed tomography findings. BLB impairment was evaluated using the signal intensity ratio, ratio of intensities between the basal turn of the cochlea and the medulla. RESULTS: SH was observed in 1/39 (3%) otosclerotic ears and BLB impairment in 8/39 (21%) while 8/29 patients with otosclerosis (28%) had vertigo. No significant associations were found between SH or BLB impairment on MRI, and the presence of vertigo or the degree of sensorineural hearing loss. CONCLUSION: Clinical manifestations of otosclerosis (sensorineural hearing loss and rotatory vertigo) were not significantly associated with MRI findings such as BLB impairment and endolymphatic hydrops. SH was only observed in one patient with obstruction of the vestibular aqueduct by an otosclerotic focus.

Comparison of Enhancement of the Vestibular Perilymph between Variable and Constant Flip Angle-Delayed 3D-FLAIR Sequences in Menière Disease.

BACKGROUND AND PURPOSE: Endolymphatic hydrops in patients with Menière disease relies on delayed postcontrast 3D-FLAIR sequences. The purpose of this study was to compare the degree of perilymphatic enhancement and the detection rate of endolymphatic hydrops using constant and variable flip angles sequences. MATERIALS AND METHODS: This was a retrospective study performed in 16 patients with Menière disease who underwent 3T MR imaging 4 hours after gadolinium injection using two 3D-FLAIR sequences with a constant flip angle at 140° for the first and a heavily-T2 variable flip angle for the second. The signal intensity ratio was measured using the ROI method. We graded endolymphatic hydrops and evaluated the cochlear blood-labyrinth barrier impairment. RESULTS: Both for symptomatic and asymptomatic ears, the median signal intensity ratio was significantly higher with the constant flip angle than with the heavily-T2 variable flip angle (7.16 versus 1.54 and 7.00 versus 1.45, P < .001). Cochlear blood-labyrinth barrier impairment was observed in 4/18 symptomatic ears with the heavily-T2 variable flip angle versus 8/19 with constant flip angle sequences. With heavily-T2 variable flip angle sequences, endolymphatic hydrops was observed in 7-10/19 symptomatic ears versus 12/19 ears with constant flip angle sequences. We found a significant association between the clinical symptomatology and the presence of endolymphatic hydrops with constant flip angle but not with heavily-T2 variable flip angle sequences. Interreader agreement was always perfect with constant flip angle sequences while it was fair-to-moderate with heavily-T2 variable flip angle sequences. CONCLUSIONS: 3D-FLAIR constant flip angle sequences provide a higher signal intensity ratio and are superior to heavily-T2 variable flip angle sequences in reliably evaluating the cochlear blood-labyrinth barrier impairment and the endolymphatic space.

Empty Sella Is a Sign of Symptomatic Lateral Sinus Stenosis and Not Intracranial Hypertension.

BACKGROUND AND PURPOSE: Empty sella has been reported in patients with idiopathic intracranial hypertension and is thought to be a sign of elevation of intracranial pressure. However, it can also be found in patients with lateral sinus stenosis presenting with isolated pulsatile tinnitus without signs of intracranial hypertension. We hypothesized that the volume of the sella turcica would be similar in both groups of patients undergoing stent placement for lateral sinus stenosis. MATERIALS AND METHODS: Consecutive patients with idiopathic intracranial hypertension or isolated venous pulsatile tinnitus and undergoing lateral sinus stent placement from January 2012 to December 2017 were included. The primary outcome was the estimated volume of the sella turcica based on preoperative CTA measurements. The ratio of the pituitary gland height/sellar height was calculated on preoperative MR imaging. Sellar volumes were compared among the 3 groups: pulsatile tinnitus, idiopathic intracranial hypertension, and a control group, matched by age and sex. RESULTS: Eighty-eight patients underwent lateral sinus stent placement. The median age was 37 years, and 94% were women. No difference in age, sex, or body mass index was found among the groups. Patients undergoing venous stent placement had significantly higher sellar volumes than the control group (P < 0.001). There was no difference in the sellar volumes (P = .63) or gland/sellar height ratios (P = .25) between the pulsatile tinnitus and idiopathic intracranial hypertension groups. CONCLUSIONS: Empty sella is found in 2 differing groups of patients undergoing lateral sinus stent placement, suggesting that it is a radiologic sign of symptomatic hemodynamic lateral sinus stenosis rather than elevated intracranial pressure.

Distal Balloon Angioplasty of Cerebral Vasospasm Decreases the Risk of Delayed Cerebral Infarction.

BACKGROUND AND PURPOSE: Conventional angioplasty of cerebral vasospasm combines proximal balloon angioplasty (up to the first segment of cerebral arteries) with chemical angioplasty for distal arteries. Distal balloon angioplasty (up to the second segment of cerebral arteries) has been used in our center instead of chemical angioplasty since January 2015. We aimed to assess the effect of this new approach in patients with aneurysmal SAH. MATERIALS AND METHODS: The occurrence, date, territory, and cause of any cerebral infarction were retrospectively determined and correlated to angioplasty procedures. Delayed cerebral infarction, new angioplasty in the territory of a previous angioplasty, angioplasty complications, 1-month mortality, and 6- to 12-month modified Rankin Scale ≤ 2 were compared between 2 periods (before-versus-after January 2015, from 2012 to 2017) with adjustment for age, sex, World Federation of Neurosurgical Societies score, and the modified Fisher grade. RESULTS: Three-hundred-ninety-two patients were analyzed (160 before versus 232 after January 2015). Distal balloon angioplasty was associated with the following: higher rates of angioplasty (43% versus 27%, P < .001) and intravenous milrinone (31% versus 9%, P < .001); lower rates of postangioplasty delayed cerebral infarction (2.2% versus 7.5%, P = .01) and new angioplasty (8% versus 19%, P = .003) independent of the rate of patients treated by angioplasty and milrinone; and the same rates of stroke related to angioplasty (3.6% versus 3.1%, P = .78), delayed cerebral infarction (7.7% versus 12.5%, P = .12), mortality (10% versus 11%, P = .81), and favorable outcome (79% versus 73%, P = .21). CONCLUSIONS: Our study suggests that distal balloon angioplasty is safe and decreases the risk of delayed cerebral infarction and the recurrence of vasospasm compared with conventional angioplasty. It fails to show a clinical benefit possibly because of confounding changes in adjuvant therapies of vasospasm during the study period.

Postoperative MR imaging features after superior semicircular canal plugging in Minor syndrome.

PURPOSE: To report the postoperative magnetic resonance imaging (MRI) features after superior semicircular canal plugging in patients with Minor syndrome. MATERIALS AND METHODS: The MRI examinations with 3D T2-weighted SPACE sequence of 12 patients with superior semicircular canal dehiscence syndrome (SCDS) were retrospectively assessed. Two radiologists independently evaluated the presence of a filling defect of the superior semicircular canal above the superior ampulla and the common crus using an oblique plane parallel to the superior semicircular canal (Pöschl's plane). RESULTS: Postoperative MRI showed a filling defect above the ampulla of the superior semicircular canal and the common crus in 8/12 patients (67%). Three patients (3/12; 25%) had a filling defect involving also the superior ampulla that caused postoperative labyrinthitis with labyrinthine enhancement on MRI in 2 patients. One patient (1/12; 8%) had incomplete plugging of superior semicircular canal with abnormal functional tests and remaining symptoms. CONCLUSION: Postoperative MRI shows a normal plugging aspect of the superior semicircular canal in 67% of patients. MRI can reveal complications that may have therapeutic implications.

Endovascular management of extracranial occlusions at the hyperacute phase of stroke with tandem occlusions.

BACKGROUND AND PURPOSE: The management of cervical artery occlusions in hyperacute stroke with tandem cervical/intracranial occlusions has not yet become standardized, especially when the circle of Willis is effective. METHODS: We retrospectively analyzed the safety and accuracy of current approaches to manage the cervical occlusion in consecutive patients with tandem occlusions addressed for intracranial mechanical thrombectomy (MT) in our department from January 2012 to May 2017. The different approaches that could be performed in a same patient during the same procedure or hospitalization were analyzed separately. RESULTS: We reported 64 approaches to manage the cervical occlusion in 49 patients with tandem occlusion (14% of MT): medical treatment alone in 16/64 (25%), stenting/angioplasty in 16/64 (25%), occlusion with coils in 12/64 (19%), angioplasty alone in 9/64 (14%), stent-retriever in 8/64 (12%), and/or thromboaspiration in 3/64 (5%). Early ipsilateral embolic recurrence occurred after 9/64 (14%) of them. It was strongly associated with the presence of a cervical intraluminal thrombus (P=0.001) and was then lower after occlusion with coils and stent-retriever compared to medical treatment alone and thromboaspiration (P=0.002). Occlusion with coils had a lower rate of radiological intracranial hemorrhage at 48-hour compared to other approaches (P=0.009). The 3-month rates of favorable outcome (P=0.806) and mortality (P=0.878) were similar. One delayed stroke was imputable to an occlusion with coils, for a median (Q1-Q3) follow-up of 10 (3-20) months. CONCLUSIONS: Cervical occlusion with coils and thrombectomy with stent-retrievers may be relevant to prevent early embolic recurrence in cervical occlusions with intraluminal thrombus. Stent-retrievers should be further assessed as a first-line approach, since delayed stroke may occur following occlusion with coils. Medical treatment alone may be sufficient when no cervical intraluminal thrombus is present, the Willis polygon is effective, and the cervical occlusion can be crossed easily to perform the intracranial thrombectomy.

Parent artery occlusion in large, giant, or fusiform aneurysms of the carotid siphon: clinical and imaging results.

BACKGROUND AND PURPOSE: Parent artery occlusion has long been considered the reference treatment for large/giant or fusiform aneurysms of the carotid siphon. However, meager recent data exist on this technique, which tends to be replaced by stent-assisted reconstructive techniques. In our department since 2004, we have assessed the safety, efficacy, and complication risk factors of parent artery occlusion by using coils for trapping these aneurysms. MATERIALS AND METHODS: We determined retrospectively the complication rate, factors associated with the occurrence of an ischemic event, changes in symptoms of mass effect, evolution of the aneurysmal size, and the growth of an additional aneurysm after treatment. RESULTS: Fifty-six consecutive patients were included, with a median age of 54 years (range, 25-85 years; 92% women), 48% with giant aneurysms and 75% with infraclinoid aneurysms. There was a permanent morbidity rate of 5% exclusively due to ischemia, a zero mortality rate, an aneurysmal retraction rate of 91%, and an improvement rate for pain of 98% and for cranial nerve palsy of 72%, with a median follow-up of >3 years. Para-/supraclinoid topography of the aneurysm (P = .043) and the presence of cardiovascular risk factors (P = .024) were associated with an excessive risk of an ischemic event, whereas the presence of a mural thrombus had a protective role (P = .033). CONCLUSIONS: In this study, parent artery occlusion by using coils to treat large/giant or fusiform aneurysms of the carotid siphon was safe and effective, especially for giant infraclinoid aneurysms. According to recent meta-analyses, these results suggest that the validation of stent-assisted reconstructive treatments for these aneurysms requires controlled studies with parent occlusion artery.

Diaphragms of the carotid and vertebral arteries: an under-diagnosed cause of ischaemic stroke.

BACKGROUND AND PURPOSE: Diaphragms of the internal carotid and vertebral arteries as a cause of ischaemic stroke are reported and stenting of diaphragms as a therapeutic option in stroke secondary prevention is described. METHODS: Five patients were cared for in our institution from 2000 to 2011 for recurrent ischaemic strokes which were classified to be of undetermined aetiology after completion of the usual investigations. Because the patients had already had ischaemic strokes in the territory of the same artery, a conventional digital subtracted angiography was performed. A diaphragm was identified on the artery that supplied the territory in which the stroke occurred. The stroke was therefore attributed to the diaphragm. Clinical and radiological data, treatment and the clinical course of the patients was retrospectively reviewed. RESULTS: The diaphragm was located in the vertebral artery in three cases and in the bulb of the internal carotid artery in two. In all cases cerebral MR showed ischaemic strokes of different ages downstream of the diaphragm. Stenting was performed in four cases. No patient had a symptomatic recurrent ischaemic event after stenting. CONCLUSIONS: Diaphragms are a rare cause of recurrent embolic strokes which are often not detected with non-invasive imaging. Stenting appears to be a therapeutic option in stroke secondary prevention. These observations suggest that conventional angiography should be performed in cases of recurrent ischaemic strokes in the territory of a single artery and in cases of ischaemic stroke of undetermined aetiology in young adults when the usual investigations are negative.

Subarachnoid and intra-cerebral hemorrhage in young adults: rare and underdiagnosed.

OBJECTIVES: Convexity subarachnoid and intra-cerebral hemorrhages, in patients aged<50 years, are always a diagnostic challenge. This condition is characterized by acute headaches with or without neurological symptoms and/or seizures, and by the radiological demonstration of subarachnoid and/or intra-cerebral hemorrhages and, more rarely, by the association of ischemic events. PATIENTS AND METHODS: In a prospective series of 30 consecutive patients (median age 31 years; 22 women) with a subarachnoid and intra-cerebral hemorrhages, 19 were diagnosed with reversible cerebral vasoconstriction syndrome (RCVS), 7 with cerebral venous sinus thrombosis (CVST), and 4 with a bleeding mycotic aneurysm (MA). RESULTS: RCVS appeared spontaneously in 16 patients and was related to the postpartum period in three cases. Subarachnoid hemorrhage (SAH) was demonstrated in 24 patients as follows: 18 cases were in cortical areas, 4 were in the polygon of Willis, one was inter-hemispheric, and one was inter-hemispheric/intra-cerebral. A convexity pure intra-cerebral hemorrhage (ICH) was recorded in 6 cases. Among the 7 patients suffering from CVST, the superior sagittal sinus was involved in 4 cases, the transverse sinuses (TS) in 2, and the TS plus sigmoid sinus (SS) in one. CONCLUSION: The three most common causes in this series were RCVS, followed by CVST and bleeding from MA. Because of atypical clinical or radiological presentations, this large spectrum of etiologies can cause diagnostic difficulties. Therefore, careful analysis is needed to ensure correct and prompt diagnosis and to avoid any dangerous delays in management.

Dural arteriovenous fistulas presenting with reversible dementia are associated with a specific venous drainage.

BACKGROUND AND PURPOSE: Venous drainage of dural arteriovenous fistula (DAVF) with dementia has never been reported. The aim of this study was to discover if specific vascular conditions exist to develop dementia in patients with DAVF. METHODS: Venous drainage in patients embolized in our centre between 1996 and 2012 for a DAVF with dementia were qualitatively analyzed and compared with a control group without dementia. RESULTS: Eight patients with dementia and 45 control patients were included. The prevalence of dementia was 4%. Diffuse hemispheric white matter lesions on magnetic resonance imaging (MRI) were consistently associated with dementia. Cognitive symptoms dramatically improved after embolization. The consistent angiographic feature in patients with dementia was drainage of the DAVF into both the straight sinus and the superior sagittal sinuses. Only two patients in the control group had similar abnormalities. CONCLUSIONS: The association of a reflux from the fistula into the straight sinus and the superior sagittal sinuses is a necessary condition to develop such a reversible dementia in DAVF. Venous hypertension in the territory of transparenchymal veins may explain this reversal phenomenon. A rapidly progressive dementia with diffuse white matter lesions on MRI should evoke this diagnosis to the physician.

[Usefulness of Bispectral Index (BIS) monitoring for early detection of cerebral hypoperfusions]. / Intérêt du monitorage de l'index bispectral (BIS) pour la détection précoce des hypoperfusions cérébrales.

OBJECTIVES: The goal of the study was to assess whether clinically significant cerebral hypoperfusion in awake patients would be associated with some alterations in the values of the bispectral index (BIS) monitoring. STUDY DESIGN: Observational study. POPULATION AND METHODS: We monitored the BIS during endovascular carotid artery occlusion testing in awake patients. RESULTS: Twenty-eight patients were included. Twenty-one adequately tolerated the procedure. Their BIS value remained stable throughout the procedure. Four patients had poor angiographic tolerance, but no clinical symptoms. Their BIS value slightly decreased during the test (minimal BIS: 83 [79-87]). Three patients had poor clinical and angiographic tolerance of the occlusion. They all experienced an immediate and dramatic decrease in their BIS value (minimal BIS: ipsilateral to clamping: 50 [45-60]; contralateral to clamping: 48 [45-52]). In all patients, the clinical symptoms and the BIS normalized after deflating the occlusion balloon. CONCLUSION: In awake patients, the observed values of the BIS monitoring seem to be associated with clinically relevant cerebral hypoperfusion.

Epileptic seizures at initial presentation in patients with brain arteriovenous malformation.

OBJECTIVES: Brain arteriovenous malformations (AVMs) often present with epileptic seizures, but prospective data on the risk of seizures with respect to morphologic AVM characteristics are scarce. METHODS: We studied 155 consecutive patients with AVMs from a prospective, single-center database using demographic and morphologic factors based on prospectively coded MRI and digital subtraction angiography (DSA) data. Univariate analysis and multivariate logistic regression models were used to test the effect of demographic (age and sex) and morphologic characteristics (AVM size, anatomic and arterial location, and venous drainage pattern) on seizures as initial presentation in patients with unruptured brain AVMs. RESULTS: Overall, 45 patients with AVMs initially presented with seizures (29%). By univariate comparison, male sex (p = 0.02), increasing AVM size (p < 0,006), frontal lobe localization (p < 0.0001), arterial borderzone location (p < 0.0006), superficial venous drainage (p = 0.0002), and presence of venous ectasia (p = 0.003) were statistically associated with seizures. The multivariate analysis confirmed an independent effect of male sex, frontal lobe AVMs, and arterial borderzone location on seizure occurrence. All patients with seizures showed the presence of a superficial venous drainage component. CONCLUSIONS: Our study suggests that seizures mainly occur in AVMs with superficial drainage. Other predisposing factors include male sex, increasing AVM size, and frontal lobe and arterial borderzone location. Whether or not interventional treatment has an effect on the long-term risk of epilepsy remains to be determined.

The use of Onyx in different types of intracranial dural arteriovenous fistula.

BACKGROUND AND PURPOSE: Recently some series have been published about the use of Onyx for the treatment of DAFVs with satisfactory results. Our aim was to describe the treatment of different types of intracranial DAVFs with transcatheter injection of Onyx through an arterial approach. MATERIALS AND METHODS: At the Department of Interventional Neuroradiology, Hospital Lariboisière Paris, between January 2005 and January 2010, we treated 44 DAVFs in 42 patients. All patients were initially treated by arterial injection of Onyx. The average patient age was 56 years (range, 27-86 years), and there were 17 women and 25 men treated. RESULTS: A total of 58 arterial pedicles were catheterized, with the middle meningeal artery representing the most common site (n = 38). The average time of injection was 30 minutes (range, 15-60 minutes), and the average amount of Onyx was 2.5 mL (range, 0.6-6.5 mL). Of the 20 fistulas with direct venous drainage into a dural sinus (types I and II), we achieved the preservation of the sinus in 7 patients. Of the 44 fistulas embolized, 8 required a second embolization treatment and 1 fistula required a third treatment. In 9 cases, a complementary treatment was performed via transvenous embolization with coils and/or open surgery. Early complications were observed in 6 patients: Four had nerve injury (facial palsy, n = 2, and neuralgia, n = 2), and 2 had complications related to extension of venous thrombosis postembolization. All 6 patients had partial or complete resolution of these symptoms. CONCLUSIONS: The treatment of DAVFs by intracranial arterial injection of Onyx is safe, and, in most cases, results in the occlusion of the arterial venous shunt. In DAVFs with direct sinus drainage, sinus preservation was only possible in 7 of 20 patients (35%).