Value of 4D MR angiography at 3T compared with DSA for the follow-up of treated brain arteriovenous malformation.

BACKGROUND AND PURPOSE: Four-dimensional, contrast-enhanced MRA is a useful technique for the diagnosis and classification of brain AVM. The purpose of this study was to evaluate its usefulness in the follow-up of treated brain AVM. MATERIALS AND METHODS: Patients with treated brain AVM (embolization, radiosurgery, and/or surgery) were investigated with both DSA (the "gold standard") and 4D MRA. Four-dimensional MRA was performed at 3T using a 4D sequence, combining contrast-enhanced timing-robust angiography, keyhole, and sensitivity encoding techniques. Examinations were evaluated by 2 independent readers and disagreements were resolved by a third reader. Interobserver and intermodality agreement with respect to residual nidus, residual venous drainage, and brain AVM patency were determined. RESULTS: Between May 2008 and February 2013, 37 patients with a median age of 45 years (interquartile range = 26-55) were prospectively included. Examinations were acquired 36 months (IQR = 10-45.5) after the last treatment. Interobserver agreement for brain AVM patency was very good for both 4D MRA (κ 0.82, 95% CI .67-.98) and DSA (κ 0.84, 95% CI .69-.98). After consensus reading, intermodality agreement for the evaluation of brain AVM patency was good (κ 0.73, 95% CI .55-.90). Diagnostic accuracy of 4D MRA for residual brain AVM compared with DSA, reached a sensitivity of 73.7%, specificity 100%, positive predictive value 100%, and negative predictive value 78.3%. Agreements by technique of treatment are also detailed. CONCLUSIONS: Four-dimensional MRA is a useful radiation-free technique for the follow-up of patients with treated brain AVM, especially patients treated by radiosurgery. However, given its actual limitations it is not sufficient to assert the cure; DSA remains mandatory for this purpose.

Combined treatment of brain AVMs with use of Onyx embolization followed by radiosurgery.

BACKGROUND AND PURPOSE: The treatment of cerebral AVMs is complex, reliant on interventions such as embolization, surgery, and radiosurgery, or a combination of these modalities. To date, treatment with the embolic agent Onyx, followed by radiosurgery, has not been evaluated. The goal of this study was to evaluate the safety and efficacy of this combination in a homogeneous, monocentric series. MATERIALS AND METHODS: From April 2003 to June 2008, a total of 20 patients (11 women and 9 men; age range, 10-55 years) were treated for AVMs with Onyx embolization followed by radiosurgery. AVM sizes were <3 cm in 7 patients and ≥3 cm in 13 patients. Modalities and complications of the procedure were analyzed as well as the long-term clinical and anatomic outcomes (2-5 years after treatment). RESULTS: Of 17 patients evaluated by DSA after radiosurgery, 10 (58.8%) were observed to have complete occlusion of the AVM nidus. Complete occlusion was observed in 5 (71.4%) of 7 Spetzler-Martin grade I-II AVMs and in 5 (50.0%) of 10 Spetzler-Martin grade III-IV AVMs. Complete occlusion was observed in 4 (80.0%) of 5 AVMs of <3 cm and 6 (50.0%) of 12 AVMs of >3 cm. One of 20 patients had significant worsening of clinical status (mRS ≥2) at long-term follow-up. CONCLUSIONS: In this preliminary series, the safety and efficacy of combined treatment by Onyx embolization followed by radiosurgery are quite satisfactory, with a low rate of clinical complications (5.0%) and a 58.8% rate of complete obliteration of the AVM.

Mechanical thrombectomy in acute stroke: prospective pilot trial of the solitaire FR device while under conscious sedation.

BACKGROUND AND PURPOSE: The best approach between general anesthesia and conscious sedation to perform mechanical thrombectomy remains unknown. The goal of our study was to evaluate the feasibility, safety, and efficacy of mechanical thrombectomy under conscious sedation in patients with acute ischemic stroke, using the Solitaire FR device, in a prospective, single-center, single-arm study. MATERIALS AND METHODS: The study included consecutive patients with acute ischemic stroke due to a large artery occlusion within 6 hours of symptom onset for the anterior circulation, and within 24 hours for the posterior circulation. After intravenous thrombolysis (when no contraindications), thrombectomy was performed with the Solitaire device in patients under conscious sedation. Primary efficacy and safety end points were good functional outcome (mRS ≤2) at 3 months and mortality at 3 months. Secondary end points were recanalization (TICI ≥2) and failure rate. RESULTS: From May 2010 to July 2011, 36 patients were treated. Median baseline NIHSS score was 17.5. The occlusion site was MCA in 21 patients (58.4%), ICA-MCA tandem occlusion in 9 patients (25.0%), terminal ICA in 2 patients (5.5%), and basilar artery in 4 patients (11.1%). Twenty-three patients (63.9%) received intravenous thrombolysis. Superselective catheterization of the occluded vessel was not feasible in 5/36 cases (13.9%). Successful revascularization was achieved in 28/36 patients (77.8%). After 3 months, 22 patients (61.1%) showed good functional outcome (mRS ≤2) and the median NIHSS score was 8.5. Overall mortality rate at 3 months was 22.2% (8/36). CONCLUSIONS: In acute ischemic stroke, mechanical thrombectomy while under conscious sedation is feasible in a large percentage of cases (86.1%) and is associated with a short procedure delay and a high percentage of good functional outcomes at 3 months (61.1%).

Intrasaccular flow-disruption treatment of intracranial aneurysms: preliminary results of a multicenter clinical study.

BACKGROUND AND PURPOSE: The endovascular treatment of intracranial aneurysms with unfavorable anatomy (large aneurysms, wide-neck) is frequently challenging and is also associated with a high incidence of significant recurrences. The WEB, an intrasaccular flow disrupter, was designed for use in this type of aneurysm. We report our early experience with this device in this multicenter study. MATERIALS AND METHODS: Twenty patients with 21 aneurysms were treated by using the WEB in 3 European centers. The ability to successfully deploy the WEB, immediate posttreatment angiographic results, adverse events, clinical outcome, and angiographic follow-up results were recorded. RESULTS: Aneurysm location was the ICA (4/21, 19.1%), MCA (8/21, 38.1%), AcomA (5/21, 23.8%), and BA (4/21, 19.1%). No treatment failures were reported. Treatment was performed exclusively with the WEB in 16/21 (76.2%) patients. Additional treatment (coiling and/or stent placement) was used in 5/21 (23.8%) patients. One patient (4.8%) experienced transient clinical worsening (mRS 1 at 1 month, mRS 0 at 3 months) related to a thromboembolic event. Inadvertent detachment of the WEB was observed, and the WEB was retrieved in 1 patient, without adverse effects. In the short-term follow-up (2-8 months), adequate occlusion (total occlusion or neck remnant) was observed in 80.0% of aneurysms. CONCLUSIONS: Intrasaccular flow disruption is a new endovascular approach for aneurysm treatment. In our preliminary experience, this treatment was feasible and mostly used in bifurcation aneurysms (MCA, BA, ICA) with unfavorable anatomy. Further studies are needed to precisely evaluate the indications, safety, and efficacy of this new technique.

Brain arteriovenous malformation diagnosis: value of time-resolved contrast-enhanced MR angiography at 3.0T compared to DSA.

INTRODUCTION: This study was conducted in order to evaluate the value of time-resolved contrast-enhanced magnetic resonance angiography (TR-CE-MRA) with a 3.0-T magnetic field compared to digital subtraction angiography (DSA) as the reference standard for the diagnosis of brain arteriovenous malformation (bAVM). METHODS: Nineteen patients with 19 angiographically confirmed untreated bAVM were investigated with both DSA and TR-CE-MRA for the initial diagnosis. Examinations were compared by two independent readers. Interobserver agreement and intermodality agreement with respect to nidus size, arterial feeders, and venous drainage were determined using the K statistic test. Also, the quality of the TR-CE-MRA images was evaluated. RESULTS: Seventeen of the 19 bAVM (89.5%) detected with DSA were diagnosed with TR-CE-MRA. Interobserver agreement for TR-CE-MRA was good for nidus size, venous drainage, and arterial feeders (K = 0.75, 95% CI 0.50-1.00; K = 0.77, 95% CI 0.54-1.00; and K = 0.80, 95% CI 0.59-1.00 respectively). Intermodality agreement was good for nidus size and venous drainage (K = 0.75, 95% CI 0.49-1.00 and K = 0.77, 95% CI 0.54-1.00, respectively) and moderate for arterial feeders (K = 0.44, 95% CI 0.17-0.70). CONCLUSION: TR-CE-MRA at 3.0 T has a good sensitivity for bAVM detection and good agreement with DSA for determining nidus size and the type of venous drainage, suggesting that TR-CE-MRA is potentially a reliable tool for the diagnosis and assessment of bAVMs. However, it still suffers from low spatial resolution and vessel superposition, making differentiation of the arterial feeders of the nidus difficult at times.

Flow-diverter silk stent for the treatment of intracranial aneurysms: 1-year follow-up in a multicenter study.

BACKGROUND AND PURPOSE: FD stent placement is a promising therapy for challenging intracranial aneurysms. Long-term evaluations about angiographic and morphologic results are still missing. This is the aim of this multicenter series. MATERIALS AND METHODS: We report our experience and 1-year FU in a retrospective chart review of 65 consecutive subjects with 77 unruptured or recanalized aneurysms that were treated with Silk FD stents at 6 centers in France. Both angiographic and clinical results were recorded before treatment and at 6 and 12 months after treatment. At the 12-month FU, relationships between angiographic aneurysm occlusion and shrinkage of the thrombosed aneurysm sac were evaluated. RESULTS: Stent deployment was achieved in 64 cases (98.5%) and failed in 1 case (1.5%). Seven misdeployments of the Silk stent caused the occlusion of 6 parent arteries. Overall acute/subacute procedural morbidity was 7.7%, and mortality was zero. Delayed complications were observed in 10.9% of subjects. At the 6-month FU, permanent morbidity was 7.8% and mortality was 3%. Complete occlusion occurred within 6 months in 68% of aneurysms and within 12 months after treatment in 84.5% of aneurysms. At the 12-month FU, in angiographically complete occluded aneurysms, MR imaging/CT analysis showed the complete disappearance of the thrombosed aneurysm in 30% of cases and partial shrinkage in 52%; furthermore, thrombosed aneurysms were stable in 11% of cases and enlarged in 7%. CONCLUSIONS: The Silk stent is an effective tool for the treatment of challenging aneurysms because it allows complete occlusion in most cases 1 year after treatment. Permanent morbidity was 7.8%, and mortality was 3%.

Double lumen remodelling balloon: a new technique for treatment of bifurcation aneurysms.

Bifurcation aneurysms (carotid bifurcation aneurysms, top of basilar artery aneurysms and middle cerebral artery aneurysms) are frequently treated by endovascular treatment (EVT) but their treatment is sometimes difficult singularly when the neck is wide. The "remodelling technique" is used for the treatment of these difficult aneurysms. However, the use of this technique is more complicated in bifurcation aneurysms compared to side-wall aneurysms. It is effectively necessary to protect in the same time the aneurysm neck, the parent vessel, and also the collateral branches. We present endovascular treatment of two cases of bifurcation aneurysms using a new technique of remodelling for endovascular treatment of bifurcation aneurysms by using a double lumen balloon.

Direct carotid-cavernous fistula following intracavernous carotid aneurysm treatment with a flow-diverter stent. A case report.

A 39-year-old woman presented with a right intra-cavernous carotid aneurysm measuring 1.76 cm×1.33 cm. The aneurysm was treated with a self-expandable flow-diverter stent. Follow-up MRI showed normal flow in the internal carotid artery with partial thrombosis of the aneurysmal sac. Two weeks later, the patient developed a right direct carotid-cavernous fistula. The fistula was treated by transvenous route. We concluded that rupture of a previously unruptured aneurysm can occur after treatment with a flow-diverter stent.

Post-embolization perianeurysmal edema revealed by temporal lobe epilepsy in a case of unruptured internal carotid artery aneurysm treated with bare platinum coils.

We report the case of a patient with an unruptured internal carotid artery (ICA) aneurysm treated with bare platinum coils. The patient had seizures 1 month after treatment. Postoperative imaging showed perianeurysmal edema and enhancement of the aneurismal wall. After aneurysm coiling, perianeurysmal edema is an unusual complication that can be asymptomatic or cause symptoms depending on its location. Epilepsy as a clinical presentation of perianeurysmal edema has not previously been reported. Literature about post-embolization perianeurysmal edema is reviewed.

[Preoperative mixed embolization of a paraganglioma using Onyx]. / Embolisation préopératoire par abord mixte d'un paragangliome à l'aide d'Onyx.

Paragangliomas, or glomus tumors, are highly vascular benign tumors of the head and neck. Clinical symptoms are essentially progressive and neurological, involving infiltration of the regional cranial nerves. The usual treatment is surgery, which itself is a challenge because of the close proximity of vital structures and the considerable blood loss. Preoperative embolization can reduce morbidity, and several techniques have been described using arterial injection of particles or of cyanoacrylate directly into the tumor. This case report is of a patient treated by surgery using a new technique-preoperative embolization involving both the arteries and veins, and injection of Onyx, resulting in complete devascularization of the tumor's arteriovenous network.