Penumbral Rescue by normobaric O = O administration in patients with ischemic stroke and target mismatch proFile (PROOF): Study protocol of a phase IIb trial.

RATIONALE: Oxygen is essential for cellular energy metabolism. Neurons are particularly vulnerable to hypoxia. Increasing oxygen supply shortly after stroke onset could preserve the ischemic penumbra until revascularization occurs. AIMS: PROOF investigates the use of normobaric oxygen (NBO) therapy within 6 h of symptom onset/notice for brain-protective bridging until endovascular revascularization of acute intracranial anterior-circulation occlusion. METHODS AND DESIGN: Randomized (1:1), standard treatment-controlled, open-label, blinded endpoint, multicenter adaptive phase IIb trial. STUDY OUTCOMES: Primary outcome is ischemic core growth (mL) from baseline to 24 h (intention-to-treat analysis). Secondary efficacy outcomes include change in NIHSS from baseline to 24 h, mRS at 90 days, cognitive and emotional function, and quality of life. Safety outcomes include mortality, intracranial hemorrhage, and respiratory failure. Exploratory analyses of imaging and blood biomarkers will be conducted. SAMPLE SIZE: Using an adaptive design with interim analysis at 80 patients per arm, up to 456 participants (228 per arm) would be needed for 80% power (one-sided alpha 0.05) to detect a mean reduction of ischemic core growth by 6.68 mL, assuming 21.4 mL standard deviation. DISCUSSION: By enrolling endovascular thrombectomy candidates in an early time window, the trial replicates insights from preclinical studies in which NBO showed beneficial effects, namely early initiation of near 100% inspired oxygen during short temporary ischemia. Primary outcome assessment at 24 h on follow-up imaging reduces variability due to withdrawal of care and early clinical confounders such as delayed extubation and aspiration pneumonia. TRIAL REGISTRATIONS: ClinicalTrials.gov: NCT03500939; EudraCT: 2017-001355-31.

Safety and effectiveness of the LVIS and LVIS Jr devices for the treatment of intracranial aneurysms: Final results of the LEPI multicenter cohort study.

BACKGROUND: The Low profile visualized intraluminal support (LVIS)/LVIS Jr is a self-expanding braiding stent for the treatment of intracranial aneurysm. This study is to determine the safety and effectiveness of the LVIS/LVIS Jr for the treatment of intracranial aneurysms in a real-world setting. METHODS: This prospective, observational, multicenter study enrolled patients with unruptured, ruptured and recanalized intracranial aneurysms treated with the LVIS stents, between February 2018 to December 2019. Primary endpoint was the cumulative morbidity and mortality rate (CMMR) assessed at 12 months follow-up (FU). RESULTS: A total of 130 patients were included (62.3 % women, mean age 55.9 ± 11.4) on an intention-to-treat basis. Four patients (3.1 %) had 2 target aneurysms; 134 total aneurysms were treated. The aneurysms were mainly located on the middle cerebral artery (41/134; 30.6 %) and the anterior communicating artery (31/134; 23.1 %). The CMMR at 1 year linked to the procedure and/or device was 4.6 % (6/130). The overall mortality was 1.5 % (2/130), none of these deaths adjudged as being linked to the procedure and/or device. All aneurysms (134/134, 100 %) were successfully treated with LVIS stent and/or other devices. At a mean FU of 16.8 months post-procedure, complete/nearly complete occlusion was achieved in 112 aneurysms (92.6 %), and only 3 patients (2.5 %) required aneurysm retreatment. CONCLUSION: This study provides evidence that the LVIS/LVIS Jr devices are safe and effective in the treatment of complex intracranial aneurysms, with very high rates of adequate occlusion at FU. These angiographic results are stable over time with an acceptable complication rate. TRIAL REGISTRATION: ClinicalTrial.gov under NCT03553771.

"National survey for preliminary evaluation of neuroradiological protocols in patients with infective endocarditis".

OBJECTIVES: The aim of this study was to identify imaging protocols in patients with infective endocarditis through a nationwide survey. METHODS: An electronic evolutionary survey was sent to interventional Neuroradiologists among neuroradiological centers, under the aegis of the Société Française de Neuroradiologie. Among 33 contacted centers, 25 completed the survey (21 universitary hospitals and 4 peripheric hospitals). RESULTS: Most of the centers (88%) used systematic imaging screening in IE patients. MRI was the first imaging method used in 66% of cases, while CT was used in 44%. When no IIA was detectable in CT-scan screening, 6 (54,54%) stopped investigations, while 9 (81,81%) continued with MRI exploration in case of hemorrhage, ischemia or enhancement. Sulcal hemorrhage on MRI was an indication of complementary DSA in 25 centers (100%). Regarding IIA characterization, 12 centers (48%) used systematic DSA, whereas for 10 centers (40%), DSA was conditioned by hemorrhage or patient status. CONCLUSION: We highlighted large variations in Neuroimaging exploration and follow-up of IE patients in real-world practices. Expert guidelines able to standardize practices are warranted to improve the management of this serious and often misdiagnosed pathology.

Influence of prior intravenous thrombolysis in patients treated with mechanical thrombectomy for M2 occlusions: insight from the Endovascular Treatment in Ischemic Stroke (ETIS) registry.

BACKGROUND: Intravenous thrombolysis (IVT) for patients treated with mechanical thrombectomy (MT) for proximal occlusions has recently been questioned through randomized trials. However, few patients with M2 occlusions were included. We investigated the influence of prior IVT for patients presenting M2 occlusions treated with MT in comparison with MT alone. METHODS: We conducted a retrospective analysis of the Endovascular Treatment in Ischemic Stroke (ETIS) registry, a multicenter observational study. Data from consecutive patients treated with MT for M2 occlusions between January 2015 and January 2022 at 26 comprehensive stroke centers were analyzed. The primary endpoint was 90-day modified Rankin Scale score of 0-2. Outcomes were compared using propensity score approaches. We also performed sensitivity analysis in relevant subgroups of patients. RESULTS: Among 1132 patients with M2 occlusions treated with MT, 570 received prior IVT. The two groups were comparable after propensity analysis. The rate of favorable functional outcome was significantly higher in the IVT+MT group compared with the MT alone group (59.8% vs 44.7%; adjusted OR 1.38, 95% CI 1.10 to 1.75, P=0.008). Hemorrhagic and procedural complications were similar in both groups. In sensitivity analysis excluding patients with anticoagulation treatment, favorable recanalization was more frequent in the IVT+MT group (OR 1.37, 95% CI 1.11 to 1.70, P=0.004). CONCLUSIONS: In cases of M2 occlusions, prior IVT combined with MT resulted in better functional outcome than MT alone, without increasing the rate of hemorrhagic or procedural complications. These results suggest the benefit of IVT in patients undergoing MT for M2 occlusions.

Antithrombotic therapies for neurointerventional surgery: a 2021 French comprehensive national survey.

BACKGROUND: Neurointerventionists lack guidelines for the use of antithrombotic therapies in their clinical practice; consequently, there is likely to be significant heterogeneity in antithrombotic use between centers. Through a nationwide survey, we aimed to obtain an exhaustive cross-sectional overview of antithrombotic use in neurointerventional procedures in France. METHODS: In April 2021, French neurointerventional surgery centers were invited to participate in a nationwide 51-question survey disseminated through an active trainee-led research collaborative network (the JENI-RC). RESULTS: All 40 centers answered the survey. Fifty-one percent of centers reported using ticagrelor and 43% used clopidogrel as premedication before intracranial stenting. For flow diversion treatment, dual antiplatelet therapy was maintained for 3 or 6 months in 39% and 53% of centers, respectively, and aspirin was prescribed for 12 months or more than 12 months in 63% and 26% of centers, respectively. For unruptured aneurysms, the most common heparin bolus dose was 50 IU/kg (59%), and only 35% of centers monitored heparin activity for dose adjustment. Tirofiban was used in 64% of centers to treat thromboembolic complications. Fifteen percent of these comprehensive stroke centers reported using tenecteplase to treat acute ischemic strokes. Cangrelor appeared as an emergent drug in specific indications. CONCLUSION: This nationwide survey highlights the important heterogeneity in clinical practices across centers. There is a pressing need for trials and guidelines to further evaluate and harmonize antithrombotic regimens in the neurointerventional field.

Impaired cerebrovascular reactivity is associated with recurrent stroke in patients with severe intracranial arterial stenosis: A C02 BOLD fMRI study.

BACKGROUND AND PURPOSE: Severe intracranial atherosclerotic stenosis (SIAS) remains at risk of recurrent ischemic events despite intensive medical management. Exhausted cerebrovascular reserve seems to be associated with higher risk of recurrent stroke. MATERIALS AND METHODS: We used whole brain MRI to estimate basal perfusion using dynamic susceptibility contrast and cerebrovascular reactivity (CVR) to hypercapnic challenge (CO2 inhalation) using BOLD contrast, in 20 patients with symptomatic SIAS (>70%) of the middle cerebral artery (MCA) or the distal internal carotid artery. We studied relationships between individual clinical, biological, radiological baseline characteristics, recurrent ischemic events, basal perfusion parameters (mean transit time, delay, time to peak, cerebral blood flow and volume), and CVR measured in MCA territories (CVRMCA), and reported using laterality indices (LI). RESULTS: Ten patients had an impaired CVR with (|LI| CVRMCA≥0.08). During a mean follow-up of 3.3 years, all recurrent ipsilateral ischemic events occurred within the first year. They were more frequent in impaired CVRMCA group (n=7/10 patients) than in normal CVRMCA group (n=1/10), with different survival curves (log rank, P=0.007). CONCLUSION: Impaired CVR is associated with an increased rate of recurrent stroke in patients with symptomatic SIAS. CVR mapping should be used as a well tolerated method to select higher-risk patients in further therapeutic trials such as endovascular procedures.

Facet joint syndrome: from diagnosis to interventional management.

Low back pain (LBP) is the most common pain syndrome, and is an enormous burden and cost generator for society. Lumbar facet joints (FJ) constitute a common source of pain, accounting for 15-45% of LBP. Facet joint degenerative osteoarthritis is the most frequent form of facet joint pain. History and physical examination may suggest but not confirm facet joint syndrome. Although imaging (radiographs, MRI, CT, SPECT) for back pain syndrome is very commonly performed, there are no effective correlations between clinical symptoms and degenerative spinal changes. Diagnostic positive facet joint block can indicate facet joints as the source of chronic spinal pain. These patients may benefit from specific interventions to eliminate facet joint pain such as neurolysis, by radiofrequency or cryoablation. The purpose of this review is to describe the anatomy, epidemiology, clinical presentation, and radiologic findings of facet joint syndrome. Specific interventional facet joint management will also be described in detail. TEACHING POINTS: • Lumbar facet joints constitute a common source of pain accounting of 15-45%. • Facet arthrosis is the most frequent form of facet pathology. • There are no effective correlations between clinical symptoms, physical examination and degenerative spinal changes. • Diagnostic positive facet joint block can indicate facet joints as the source of pain. • After selection processing, patients may benefit from facet joint neurolysis, notably by radiofrequency or cryoablation.

Greater occipital nerve MR tractography: Feasibility and anatomical considerations.

BACKGROUND AND PURPOSE: To assess the feasibility of greater occipital nerve (GON) tractography using a fully automated tractography technique on the whole-neck volume, in comparison with anatomical knowledge. METHODS: Healthy subjects were consecutively included in this study if they had no history or symptoms of headache or brain disorder. A 3T MRI scanner with a 32 channel head coil was used. The following parameters for Diffusion Weighed (DWI) were used: b value of 1000 s/mm2, 32 directions, acquired voxel size: 2 mm isotropic. High-Order tractography with the Constrained Spherical Deconvolution (CSD) model was generated. Track-Weighted Imaging (TWI) maps were generated with MRTrix. Two radiologists performed blind evaluations of the GON pathways on TWI maps. RESULTS: A total of 20 healthy subjects were included (12 males and eight females, mean age 53.8 years old). In comparison with anatomical atlas, GON complete visualization (from C1-C2 origin to muscular emergence) was possible in 18 out of 20 healthy subjects. In two cases, GON was not visible in the cervical spine foramen. CONCLUSION: Tractography through TWI is a feasible technique to accurately depict GON. This technique may appear as a promising technique for therapeutic management of patients with occipital neuralgia.

Parietal operculum and motor cortex activities predict motor recovery in moderate to severe stroke.

While motor recovery following mild stroke has been extensively studied with neuroimaging, mechanisms of recovery after moderate to severe strokes of the types that are often the focus for novel restorative therapies remain obscure. We used fMRI to: 1) characterize reorganization occurring after moderate to severe subacute stroke, 2) identify brain regions associated with motor recovery and 3) to test whether brain activity associated with passive movement measured in the subacute period could predict motor outcome six months later. Because many patients with large strokes involving sensorimotor regions cannot engage in voluntary movement, we used passive flexion-extension of the paretic wrist to compare 21 patients with subacute ischemic stroke to 24 healthy controls one month after stroke. Clinical motor outcome was assessed with Fugl-Meyer motor scores (motor-FMS) six months later. Multiple regression, with predictors including baseline (one-month) motor-FMS and sensorimotor network regional activity (ROI) measures, was used to determine optimal variable selection for motor outcome prediction. Sensorimotor network ROIs were derived from a meta-analysis of arm voluntary movement tasks. Bootstrapping with 1000 replications was used for internal model validation. During passive movement, both control and patient groups exhibited activity increases in multiple bilateral sensorimotor network regions, including the primary motor (MI), premotor and supplementary motor areas (SMA), cerebellar cortex, putamen, thalamus, insula, Brodmann area (BA) 44 and parietal operculum (OP1-OP4). Compared to controls, patients showed: 1) lower task-related activity in ipsilesional MI, SMA and contralesional cerebellum (lobules V-VI) and 2) higher activity in contralesional MI, superior temporal gyrus and OP1-OP4. Using multiple regression, we found that the combination of baseline motor-FMS, activity in ipsilesional MI (BA4a), putamen and ipsilesional OP1 predicted motor outcome measured 6 months later (adjusted-R2 = 0.85; bootstrap p < 0.001). Baseline motor-FMS alone predicted only 54% of the variance. When baseline motor-FMS was removed, the combination of increased activity in ipsilesional MI-BA4a, ipsilesional thalamus, contralesional mid-cingulum, contralesional OP4 and decreased activity in ipsilesional OP1, predicted better motor outcome (djusted-R2 = 0.96; bootstrap p < 0.001). In subacute stroke, fMRI brain activity related to passive movement measured in a sensorimotor network defined by activity during voluntary movement predicted motor recovery better than baseline motor-FMS alone. Furthermore, fMRI sensorimotor network activity measures considered alone allowed excellent clinical recovery prediction and may provide reliable biomarkers for assessing new therapies in clinical trial contexts. Our findings suggest that neural reorganization related to motor recovery from moderate to severe stroke results from balanced changes in ipsilesional MI (BA4a) and a set of phylogenetically more archaic sensorimotor regions in the ventral sensorimotor trend, in which OP1 and OP4 processes may complement the ipsilesional dorsal motor cortex in achieving compensatory sensorimotor recovery.

Potentially stress-induced acute splanchnic segmental arterial mediolysis with a favorable spontaneous outcome.

A 62-year-old woman presented with hemithoracic anesthesia and acute abdominal pain following a violent psychological stress. Magnetic resonance imaging showed a thoracic hematoma with arachnoiditis of the spinal cord. Tomography revealed a typical aspect of segmental arterial mediolysis with multiple aneurysms and stenoses of the splanchnic arteries, confirmed by abdominal arteriography. There was no argument for hereditary, traumatic, atherosclerotic, infectious, or inflammatory arterial disease. Segmental arterial mediolysis was diagnosed on the basis of the radiologic data and probably involved both medullary and splanchnic arteries. The patient spontaneously recovered and was in good health 18 months later.

Post traumatic deafness: a pictorial review of CT and MRI findings.

UNLABELLED: Hearing loss is a common functional disorder after trauma, and radiologists should be aware of the ossicular, labyrinthine or brain lesions that may be responsible. After a trauma, use of a systematic approach to explore the main functional components of auditory pathways is essential. Conductive hearing loss is caused by the disruption of the conductive chain, which may be due to ossicular luxation or fracture. This pictorial review firstly describes the normal 2-D and 3-D anatomy of the ossicular chain, including the incudo-malleolar and incudo-stapedial joints. The role of 3-D CT in the post-traumatic evaluation of injury to the temporal bone is then evaluated. In the case of sensorineural hearing loss, CT can detect pneumolabyrinth and signs of perilymphatic fistulae but fails to detect subtle lesions within the inner ear, such as labyrinthine haemorrhage or localized brain axonal damage along central auditory pathways. The role that MRI with 3-D-FLAIR acquisition plays in the detection of inner ear haemorrhage and post-traumatic lesions of the brain parenchyma that may lead to auditory agnosia is also discussed. KEY POINTS: • The most common middle ear injuries are incudo-malleolar and incudo-stapedial joint luxation. • In patients with SNHL, CT can detect pneumolabyrinth or perilymphatic fistula • 3-D-FLAIR MRI appears the best sequence to highlight labyrinthine haemorrhage • Axonal damage and brain hematoma may lead to deafness.

Diffusion MRI: Pitfalls, literature review and future directions of research in mild traumatic brain injury.

Mild traumatic brain injury (mTBI) is a leading cause of disability in adults, many of whom report a distressing combination of physical, emotional and cognitive symptoms, collectively known as post-concussion syndrome, that persist after the injury. Significant developments in magnetic resonance diffusion imaging, involving voxel-based quantitative analysis through the measurement of fractional anisotropy or mean diffusivity, have enhanced our knowledge on the different stages of mTBI pathophysiology. Other diffusion imaging-derived techniques, including diffusion kurtosis imaging with multi-shell diffusion and high-order tractography models, have recently demonstrated their usefulness in mTBI. Our review starts by briefly outlining the physical basis of diffusion tensor imaging including the pitfalls for use in brain trauma, before discussing findings from diagnostic trials testing its usefulness in assessing brain structural changes in patients with mTBI. Use of different post-processing techniques for the diffusion imaging data, identified the corpus callosum as the most frequently injured structure in mTBI, particularly at sub-acute and chronic stages, and a crucial location for evaluating functional outcome. However, structural changes appear too subtle for identification using traditional diffusion biomarkers, thus disallowing expansion of these techniques into clinical practice. In this regard, more advanced diffusion techniques are promising in the assessment of this complex disease.

Rupture of lenticulostriate artery aneurysms.

The authors report on 3 rare cases of ruptured lenticulostriate artery (LSA) aneurysms that were heralded by deep cerebral hematomas. The hematomas were unilateral in 2 cases and bilateral in 1; in the bilateral case, only a single LSA aneurysm could be identified on the right side of the brain. Because of their small size (≤ 2 mm), fusiform aspect, and deep location within the brain, all of the aneurysms were treated conservatively. There was no hemorrhage recurrence, and follow-up angiography demonstrated spontaneous thrombosis in 2 of the 3 cases. The clinical course was favorable in 2 of the 3 patients. The course in the patient with the bilateral hematoma was marked by an ischemic event after the initial episode, resulting in an aggravation of deficits. The cause of this second event was uncertain. Because our knowledge about the natural history of LSA aneurysms is incomplete, there is no consensus concerning a therapeutic strategy. The authors' experience in 3 reported cases leads them to think that a conservative approach involving close angiographic monitoring may be proposed as first-line treatment. If the monitored aneurysm then persists or grows in size, its occlusion should be considered. Nonetheless, other studies are needed to further strengthen the legitimacy of this strategy.