René Anxionnat

Ruptured Intracranial Aneurysms: Factors Affecting the Rate and Outcome of Endovascular Treatment Complications in a Series of 782 Patients (CLARITY Study)

PURPOSE To analyze the clinical and anatomic factors that affect the occurrence and outcome of complications (thromboembolic events and intraoperative rupture) in the endovascular treatment of ruptured intracranial aneurysms in a large multicenter series, the CLARITY study (Clinical and Anatomic Results in the Treatment of Ruptured Intracranial Aneurysms). MATERIALS AND METHODS This study was approved by the institutional review boards of the participating centers, and written informed consent was obtained from all patients. In the CLARITY series, 782 patients (314 men, 468 women; age range, 19-80 years, mean age, 51.3 years +/- 13.2 [standard deviation]) with 782 ruptured aneurysms underwent endovascular treatment for ruptured intracranial aneurysms at 20 institutions. Uni- and multivariate analyses were performed to determine factors (demographic characteristics, risk factors, anatomic factors, and therapeutic factors) that affect the occurrence of treatment-related complications. RESULTS A higher rate of thromboembolic events was observed in patients with aneurysms larger than 10 mm (28.0% vs 10.7% in patients with aneurysms < or =10 mm, P < .001), in smokers (16.1% vs 10.1% in nonsmokers, P = .015), and in patients with aneurysms with a neck larger than 4 mm (20.8% vs 11.0% in aneurysms with a neck < or =4 mm, P = .004).The frequency of intraoperative rupture was higher in patients with middle cerebral artery (MCA) aneurysms (8.5% vs 3.7% in patients without MCA aneurysms, P = .029), in patients younger than 65 years (5.0% vs 0.8% in patients older than 65 years, P = .032), and in patients without hypertension (5.4% vs 1.5% in patients with hypertension, P = .017). CONCLUSION The rate of thromboembolic events in the endovascular treatment of ruptured aneurysms is significantly affected by aneurysm size and neck size but not by aneurysm location. Conversely, the rate of intraoperative rupture is significantly affected by aneurysm location but not aneurysm size.

Vasospasm after subarachnoid hemorrhage: interest in diffusion-weighted MR imaging.

Background and Purpose— Vasospasm secondary to subarachnoid hemorrhage (SAH) is responsible for severe ischemic complications. Although effective, angioplasty must be performed at a very early stage to produce any clinical recovery. Diagnostic investigations to assess arterial narrowing (transcranial Doppler, angiography) or cerebral perfusion (xenon CT, single-photon emission CT) do not provide evidence of the extent of parenchymal ischemia. In stroke, diffusion-weighted MR imaging (DWI) appears to be the most sensitive procedure to detect cerebral ischemia. We studied asymptomatic vasospasm in patients with aneurysmal SAH to assess whether DWI provides predictive markers of silent ischemic lesions and/or progression toward symptomatic ischemia. Methods— Seven asymptomatic vasospasm patients (average blood velocity rates >120 cm/s), 3 patients with symptomatic vasospasm, and 4 patients with SAH but without vasospasm were studied at regular intervals by DWI, and their apparent diffusion coefficients (ADCs) were calculated. Results— All patients with vasospasm including those without symptoms presented abnormalities on DWI with a reduction of the ADC prevalently in the white matter. No such abnormalities were observed in patients without vasospasm. The abnormalities on DWI resolved completely in 4 of the 7 patients, with no parenchymal lesion. Resolution was partial in 3 patients whose white matter still presented residual round, focal ischemic lesions. Conclusions— Being able to correlate abnormalities on DWI with parenchymal involvement in asymptomatic patients would be of considerable clinical significance. It is hoped that larger studies will be undertaken to determine whether the ADC has a reversibility threshold, because this would facilitate patient management.

Treatment of hemorrhagic intracranial dissections: Commentary

OBJECTIVETo analyze the treatment options in hemorrhagic intracranial dissections. METHODSThis study involved a retrospective review of 27 patients with 29 dissections treated during a 16-year period, mainly by endovascular treatment (EVT). RESULTSEVT was performed in the acute stage in 12 of the 29 dissections, and occlusion was performed using coils at the dissection site in six dissections and with proximal balloon occlusion in six dissections. Wrapping was performed in one case. In the remaining 16 dissections, which were not treated, mainly for anatomic reasons, three patients died, one from rebleeding. Angiographic follow-up performed in the 13 surviving patients demonstrated an initially misdiagnosed lesion in one and worsening lesions in five that led to delayed EVT in five and surgical clipping in one. One of these dissections, which was located on a dominant vertebral artery, was treated after subsequent rupture using a stent and coils to preserve the patency of the parent vessel. Four ischemic complications related to EVT resulted in a moderate disability in two patients. No rebleeding occurred after EVT, but one patient died because of a poor initial clinical status; the other patients improved. In the 10 patients treated conservatively, four died, three from a poor initial clinical status and one from rebleeding, and six patients had a good clinical outcome. Of the 27 patients, three had rebleeding and one died as a result of that rebleeding. Seventeen patients (63%) had a good recovery, six (22%) had a moderate disability, and four (15%) died. CONCLUSIONEVT provides effective protection against rebleeding. When possible, occlusion with coils at the dissection site is the current method of choice. Another option is parent artery occlusion with balloons, and the use of a stent may preserve vessel permeability in specific cases.

Endovascular Treatment of ACom Intracranial Aneurysms: Report on series of 280 Patients

The immediate and long-term outcomes, complications, recurrences and the need for retreatment were analyzed in a series of 280 consecutive patients with anterior communicating artery aneurysms treated with the endovascular technique. From October 1992 to October 2001 280 patients with 282 anterior communicating artery aneurysms were addressed to our center. For the analysis, the population was divided into two major groups: group 1, comprising 239 (85%) patients with ruptured aneurysms and group 2 comprising of 42 (15%) patients with unruptured aneurysms. In group 1, 185 (77.4%) patients had a good initial pre-treatment Hunt and Hess grade of I-III. Aneurysm size was divided into three categories according to the larger diameter: less than 4 mm, between 4 and 10 mm and larger than 10 mm. The sizes of aneurysms in groups 1 and 2 were identical but a less favorable neck to depth ratio of 0.5 was more frequent in group 2. Endovascular treatment was finally performed in 234 patients in group 1 and 34 patients in group 2. Complete obliteration was more frequently obtained in group 2 unlike a residual neck or opacification of the sac that were more frequently seen in group 1. No peri-treatment complications were recorded in group 2. In group 1 the peri-treatment mortality and overall peri-treatment morbidity were 5.1% and 8.1% respectively. Eight patients (3.4%) in group 1 presented early post treatment rebleeding with a mortality of 88%. The mean time to follow-up was 3.09 years. In group 1, 51 (21.7%) recurrences occurred of which 14 were minor and 37 major. In group 2, eight (23.5%) recurrences occurred, five minor and three major. Two patients (0.8%) presented late rebleeding in group 1. Twenty-seven second endovascular retreatments were performed, 24 (10.2%) in group 1 and three (8.8%) in group 2, seven third endovascular retreatments and two surgical clippings in group 1 only. There was no additional morbidity related to retreatments. Endovascular treatment is an effective method for the treatment of anterior communicating artery aneurysms allowing late rebleeding prevention. Peri-treatment rebleeding warrants caution in anticoagulation management. This is a single center experience and the follow-up period is limited. Patients should be followed-up in the long-term as recurrences may occur and warrant additional treatment.

Quantitative evaluation of an algorithm for correcting geometrical distortions in DSA images: applications to stereotaxy

In digital subtraction angiography, the use of an image intensifier as a detector introduces geometrical distortions in the images. For stereotactic applications, such as the irradiation of cerebral arteriovenous malformations, these distortions have necessarily to be corrected, and the accuracy of this correction has to be examined. As the distortions depend on many parameters that vary during an examination (such as magnetic field and spatial position of the acquisition chain), the correction accuracy must be defined as a function of the acquisition protocol. We have developed a correction method based on the calibration of geometrical distortions using an image of a grid phantom. An experimental study of the influence of acquisition parameters over the distortion has been performed. A protocol has been defined which ensures a correction accuracy of 0.1 millimeter. Finally, we have studied the accuracy obtained in the 3D location of a target as a function of the accuracy of the distortion correction. The final precision allows the use of our method for digital x-ray stereotactic applications.

Nontraumatic Subarachnoid Hemorrhage Management: Evaluation with Reduced Iodine Volume at CT Angiography

PURPOSE To evaluate the technical quality and the diagnostic performance of a protocol with use of low volumes of contrast medium (25 mL) at 64-detector spiral computed tomography (CT) in the diagnosis and management of adult, nontraumatic subarachnoid hemorrhage (SAH). MATERIALS AND METHODS This study was performed outside the United States and was approved by the institutional review board. Intracranial CT angiography was performed in 73 consecutive patients with nontraumatic SAH diagnosed at nonenhanced CT. Image quality was evaluated by two observers using two criteria: degree of arterial enhancement and venous contamination. The two independent readers evaluated diagnostic performance (lesion detection and correct therapeutic decision-making process) by using rotational angiographic findings as the standard of reference. Sensitivity, specificity, and positive and negative predictive values were calculated for patients who underwent CT angiography and three-dimensional rotational angiography. The intraclass correlation coefficient was calculated to assess interobserver concordance concerning aneurysm measurements and therapeutic management. RESULTS All aneurysms were detected, either ruptured or unruptured. Arterial opacification was excellent in 62 cases (85%), and venous contamination was absent or minor in 61 cases (84%). In 95% of cases, CT angiographic findings allowed optimal therapeutic management. The intraclass correlation coefficient ranged between 0.93 and 0.95, indicating excellent interobserver agreement. CONCLUSION With only 25 mL of iodinated contrast medium focused on the arterial phase, 64-detector CT angiography allowed satisfactory diagnostic and therapeutic management of nontraumatic SAH.

Brainstem infarction in a patient with internal carotid dissection and persistent trigeminal artery: a case report

BackgroundThe primitive trigeminal artery (PTA) is the most commonly described fetal anastomosis between the carotid and vertebrobasilar circulations.Case presentationWe report a 42-year-old patient presenting with internal carotid dissection, and imaging features of brainstem infarction.ConclusionBased on the imaging studies we presume occlusive carotid dissection with extensive thrombosis within a persistent trigeminal artery as the cause of this brainstem ischemia.

Symptomatic Radionecrosis after AVM Stereotactic Radiosurgery.: Study of 16 Consecutive Patients

The purpose of our study was to analyze the outcome of symptomatic radionecrosis following stereotactic radiosurgery for brain arterio venous malformations. Of 225 patients treated by linear accelerator radiosurgery for brain AVM, 16 (7, 1%) presented post-radiosurgery symptomatic radionecrosis on a mean follow-up period of 50 months (range 1–123 months). Once diagnosed with radionecrosis, 14 of 16 patients were subjected to high dose corticotherapy consisting of escalating doses of dexamethasone for several weeks. The mean interval of occurrence of new symptoms was 11.6 months post-radiosurgery (range 6–20 months). The mean time of follow-up was 2.9 years post radiotherap y ranging from seven months to eight years. Of the 16 patients with symptomatic radionecrosis, 11 (68, 75%) showed complete resolution of symptoms while five (31, 25%) showed improvement but still presented a neurological deficit at the closing date of the study. At the closing date, 11 patients (68.75%) had angiographically completely obliterated arterio venous malformations while another two patients had an obliteration of 95% to 98% and one patient had a 98% obliteration with development of a new contralateral AVM. In our series, symptomatic radionecrosis occurred in 7.1% of patients treated with stereotactic radiosurgery for brain AVM. These patients where subjected to a prompt, high dose corticosteroid treatment and most presented symptom resolution or improvement with a fair obliteration rate, offering protection from bleeding. Permanent neurologic deficits attributable to radionecrosis occurred in 2.2% of our patient population treated with stereotactic radiosurgery for brain AVM.

Endovascular treatment of acute ischemic stroke with ERIC device

BACKGROUND AND PURPOSE After 6 positive randomized trials, mechanical thrombectomy with stent-retriever is now recommended as a first-line treatment for acute ischemic stroke (AIS). The ERIC device is a device with several interlinked cage-like spheres fixed on a pusher wire. Neurothrombectomy France (NTF) is a registry conducted in France to analyze the results of mechanical thrombectomy. In order to analyze its performances, the subgroup of patients treated with the ERIC device was analyzed. MATERIALS AND METHODS NTF is a prospective, multicenter registry dedicated to the evaluation of endovascular treatment for AIS. Primary endpoint was modified Rankin Scale (mRS) at 3months. Secondary endpoints were revascularization at the end of the procedure evaluated with the Thrombolysis In Cerebral Infarction (TICI) scale and rate of procedural complications. Patients treated with the ERIC device were extracted from the NTF registry and analyzed. RESULTS From April 2013 to May 2014, 230 patients were included in the NTF registry. Thirty-one patients (13.5%) were treated with ERIC (male: 64.5%; median age: 61years). Median baseline NIHSS was 16. Median ASPECTS was 6. Occlusion location was internal carotid artery (51.6%), middle cerebral artery-M1 (45.2%), and basilar artery (3.2%). Cervical occlusion was associated in 16.1%. Revascularization (TICI 2b-3) was obtained in 87.1%. Good clinical outcome (mRS 0-2) at 3months was obtained in 55.2%. Death rate was 6.9% related to the stroke. CONCLUSION This prospective, multicenter series shows good performances of the ERIC device in the treatment of acute ischemic stroke with revascularization in 87.1% and favorable clinical outcome in 55.2%.

Brain AVM Embolization. Retrospective Study Concerning 728 Patients Followed between 1984 and 2004.

45Nancy deserves to be clarified because it ex-plains the specificity of this population. Indeed,until 1995, more than 60% of patients present-ing an intracerebral arteriovenous malforma-tion were addressed to the Department by for-eign neurosurgical teams. Obviously, these neu-rosurgical teams preferred to treat by them-selves patients presenting arteriovenous mal-formations considered as simple i.e. small andlocated in non eloquent cerebral territories.This explains why the percentage of large arte-riovenous malformations, located in highlyfunctional zones, seems particularly significantin our population. During the 10 last years, thepercentage of foreign patients has graduallydropped to stabilize around 33% of patients re-ferred for an arteriovenous malformation.The studied population includes 728 patientswith an increased male prevalence: 57% menand 43 % women. The date of the first symp-tom varies significantly from 1 year to 84 yearswith an average age of 29 years. The averageage of the first therapeutic intervention is de-layed compared to the age of initial diagnosis.This age is 32 years with a minimum of twoyears and a maximum of 69 years. This shows,that on average, the patients are taken incharge within only three years after the oc-curence of the first symptom and that, with theexception of cases urgently addressed becauseof severe haemorrhage, no patient was taken incharge after the age of 69. It is important to no-tice that this attitude is completely different