TAGE Score for Symptomatic Intracranial Hemorrhage Prediction After Successful Endovascular Treatment in Acute Ischemic Stroke.

BACKGROUND: Determine if early venous filling (EVF) after complete successful recanalization with mechanical thrombectomy in acute ischemic stroke is an independent predictor of symptomatic intracranial hemorrhage (sICH) and integrate EVF into a risk score for sICH prediction. METHODS: Consecutive patients with anterior acute ischemic stroke treated by mechanical thrombectomy issued from patients enrolled in the THRACE trial (Thrombectomie des Artères Cérébrales) and from 2 prospective registries were included and divided into a derivation (Center I; n=402) and validation cohorts (THRACE and center 2; n=507). EVF was evaluated by 2 blinded readers. sICH was defined according to the modified European cooperative acute stroke study II. Clinical and radiological data were analyzed in the derivation cohort (C1) to identify independent predictors of sICH and construct a predictive score test on the validation cohort (THRACE + C2). RESULTS: Symptomatic ICH rate was similar between the two cohorts (9.9% and 8.9% respectively, P=0.9). Time from onset-to-successful recanalization >270 minutes (odds ratio [OR], 7.8 [95% CI, 2.5-24]), Alberta Stroke Program Early CT Score (≤5 [OR, 2.49 (95% CI, 1.8-8.1) or 6-7 [OR, 1.15 (95% CI, 1.03-4.46)]), glucose blood level >7 mmol/L (OR, 2.92 [95% CI, 1.26-6.7]), and EVF presence (OR, 11.9 [95% CI, 3.8-37.5]) were independent predictors of sICH and constituted the Time-Alberta Stroke Program Early CT-Glycemia-EVF score. Time-Alberta Stroke Program Early CT-Glycemia-EVF score was associated with an increased risk of sICH in the derivation cohort (OR increase per unit, 1.99 [95% CI, 1.53-2.59]; P<0.001) with area under the curve, 0.832 [95% CI, 0.767-0.898]. The score had good performance in the validation cohort (area under the curve, 0.801 [95% CI, 0.69-0.91]). CONCLUSIONS: Time-Alberta Stroke Program Early CT-Glycemia-EVF score is a simple tool with readily available clinical variables with good performances for sICH prediction after mechanical thrombectomy. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT01062698.

Extensive Cerebral Venous Thrombosis Secondary to Recreational Nitrous Oxide Abuse.

Nitrous oxide, colloquially known as "whippets," is a commonly abused inhalant by adolescents and young adults. There are limited data describing the adverse effects of this abuse. We present a 16-year-old girl with no medical history who presented to the emergency department for confusion, hallucinations, weakness, and headaches. Imaging revealed extensive cerebral thrombosis. She had no prior history of venous or arterial thrombosis. Hypercoagulability workup demonstrated an elevated homocysteine level. She was treated with effective anticoagulation and vitamin B12 folate supplementation. To our knowledge, there are a very few cases in the medical literature of cerebral venous thrombosis following the use of nitrous oxide. The pathophysiology of the disorder appears to be linked to the metabolism of vitamin B12 inducing hyperhomocysteinemia and a procoagulant state.

Differentiating central from peripheral causes of acute vertigo in an emergency setting with the HINTS, STANDING, and ABCD2 tests: A diagnostic cohort study.

BACKGROUND: Diagnosing stroke in dizzy patients remains a challenge in emergency medicine. The accuracy of the neuroophthalmologic examination HINTS performed by emergency physicians (EPs) is unknown. Our objective was to determine the accuracy of the HINTS examination performed by trained EPs for diagnosing central cause of acute vertigo and unsteadiness and to compare it with another bedside clinical tool, STANDING, and with the history-based score ABCD2. METHODS: This was a prospective diagnostic cohort study among patients with isolated vertigo and unsteadiness seen in a single emergency department (ED). Trained EPs performed HINTS and STANDING tests blinded to attending physicians. ABCD2 ≥ 4 was used as the threshold and was calculated retrospectively. The criterion standard was diffusion-weighted brain magnetic resonance imaging (MRI). Peripheral diagnoses were established by a normal MRI, and etiologies were further refined by an otologic examination. RESULTS: We included 300 patients of whom 62 had a central lesion on neuroimaging including 49 strokes (79%). Of the 238 peripheral diagnoses, 159 were vestibulopathies, mainly benign paroxysmal positional vertigo (40%). HINTS and STANDING tests reached high sensitivities at 97% and 94% and NPVs at 99% and 98%, respectively. The ABCD2 score failed to predict half of central vertigo cases and had a sensitivity of 55% and a NPV of 87%. The STANDING test was more specific and had a better positive predictive value (PPV; 75% and 49%, respectively; positive likelihood ratio [LR+] = 3.71, negative likelihood ratio [LR-] = 0.09) than the HINTS test (67% and 44%, respectively; LR+ = 2.96, LR- = 0.04). The ABCD2 score was specific (82%, LR+ = 3.04, LR- = 0.56) but had a very low PPV (44%). CONCLUSIONS: In the hands of EPs, HINTS and STANDING tests outperformed ABCD2 in identifying central causes of vertigo. For diagnosing peripheral disorders, the STANDING algorithm is more specific than the HINTS test. HINTS and STANDING could be useful tools saving both time and costs related to unnecessary neuroimaging use.

MT-DRAGON score for outcome prediction in acute ischemic stroke treated by mechanical thrombectomy within 8 hours.

OBJECTIVES: The MRI-DRAGON score includes clinical and MRI parameters and demonstrates a high specificity in predicting 3 month outcome in patients with acute ischemic stroke (AIS) treated with intravenous tissue plasminogen activator (IV tPA). The aim of this study was to adapt this score to mechanical thrombectomy (MT) in a large multicenter cohort. METHODS: Consecutive cases of AIS treated by MT between January 2015 and December 2017 from three stroke centers were reviewed (n=1077). We derived the MT-DRAGON score by keeping all variables of the MRI-DRAGON score (age, initial National Institutes of Health Stroke Scale score, glucose level, pre-stroke modified Rankin Scale (mRS) score, diffusion weighted imaging-Alberta Stroke Program Early CT score ≤5) and considering the following variables: time to groin puncture instead of onset to IV tPA time and occlusion site. Unfavorable 3 month outcome was defined as a mRS score >2. Score performance was evaluated by c statistics and an external validation was performed. RESULTS: Among 679 included patients (derivation and validation cohorts, n=431 and 248, respectively), an unfavorable outcome was similar between the derivation (51.5%) and validation (58.1%, P=0.7) cohorts, and was significantly associated with all MT-DRAGON parameters in the multivariable analysis. The c statistics for unfavorable outcome prediction was 0.83 (95%CI 0.79 to 0.88) in the derivation and 0.8 (95%CI 0.75 to 0.86) in the validation cohort. All patients (n=55) with an MT-DRAGONscore ≥11 had an unfavorable outcome and 60/63 (95%) patients with an MT-DRAGON score ≤2 points had a favorable outcome. CONCLUSION: The MT-DRAGON score is a simple tool, combining admission clinical and radiological parameters that can reliably predict 3 month outcome after MT.

Precise finger somatotopy revealed by focal motor cortex injury.

BACKGROUND: Somatotopy is considered the hallmark of the primary motor cortex. While this is fundamentally true for the major body parts (head, upper and lower extremities), evidence supporting the existence of within-limb somatotopy is scarce. METHOD: We report a young man presenting recurrent ischemic strokes with selective finger weakness in whom serial motor cortex mapping procedures were performed. RESULT: Following the first stroke, which largely spared the motor cortex, motor mapping displayed overlap of the motor representations of the hand muscles. The second focal stroke, affecting the lateral part of the hand knob, resulted in selective loss of the first dorsal interosseous muscle motor evoked potentials while sparing those of the adductor digiti minimi muscle. This observation is in apparent contradiction with the first mapping results that suggested complete overlap of motor representations. DISCUSSION: Our mapping results provide evidence for the existence of very precise within-limb somatotopy and confirm the proposed homuncular order, whereby lateral fingers are represented laterally and medial fingers medially. The discrepancy between the initial and subsequent mapping results is discussed in light of functional organization of the primary motor cortex.

Efficacy of Endovascular Therapy in Acute Ischemic Stroke Depends on Age and Clinical Severity.

BACKGROUND AND PURPOSE: Efficacy of endovascular treatment (EVT) for ischemic stroke because of large vessel occlusion may depend on patients' age and stroke severity; we, therefore, developed a prognosis score based on these variables and examined whether EVT efficacy differs between patients with good, intermediate, or poor prognostic score. METHODS: A total of 4079 patients with an acute ischemic stroke were identified from the Paris Stroke Consortium registry. We developed the stroke checkerboard (SC) score (SC score=1 point per decade ≥50 years of age and 2 points per 5 points on the National Institutes of Health Stroke Scale) to predict spontaneous outcome. The primary outcome was the adjusted common odds ratio for an improvement in the modified Rankin Scale at 90 days after EVT, in patients with low, intermediate, or high SC scores. To rule out potential selection biases, a nested case-control analysis, with individual matching for all major prognostic factors, was also performed, to compare patients with large vessel occlusion in the anterior circulation treated or not with EVT. RESULTS: In patients untreated with EVT, SC scores <8 were predictive of good outcomes (modified Rankin Scale score, 0-2; area under the curve, 0.87), whereas SC scores >12 were predictive of poor outcomes (modified Rankin Scale score, 4-6; area under the curve, 0.88). In the overall population, there was an interaction between EVT and prognosis group (P<0.001). EVT was associated with improved outcome in patients with SC scores >12 (common odds ratio, 1.70; 95% confidence interval, 1.13-2.56) and SC scores 8 to 12 (odds ratio, 1.37; 95% confidence interval, 1.11-1.69) but not in patients with SC scores <8 (odds ratio, 0.72; 95% confidence interval, 0.56-0.93). Similar results were obtained in the case-control analysis among 449 patients treated with EVT and 449 matched patients untreated with EVT. CONCLUSIONS: In patients stratified with the SC score, EVT was associated with improved functional outcome in older and more severe patients but not in younger and less severe patients.

Combining Standard Conventional Measures and Ecological Momentary Assessment of Depression, Anxiety and Coping Using Smartphone Application in Minor Stroke Population: A Longitudinal Study Protocol.

Context: Stroke has several consequences on survivors' daily life even for those who experience short-lasting neurological symptoms with no functional disability. Depression and anxiety are common psychological disorders occurring after a stroke. They affect long-term outcomes and quality of life but they are difficult to diagnose because of the neurobiological consequences of brain lesions. Current research priority is given to the improvement of the detection and prevention of those post-stroke psychological disorders. Although previous studies have brought promising perspectives, their designs based on retrospective tools involve some limits regarding their ecological validity. Ecological Momentary Assessment (EMA) is an alternative to conventional instruments that could be a key in research for understanding processes that underlined post-stroke depression and anxiety onset. We aim to evaluate the feasibility and validity of anxiety, depression and coping EMA for minor stroke patients. Methods: Patients hospitalized in an Intensive Neuro-vascular Care Unit between April 2016 and January 2017 for a minor stroke is involved in a study based on an EMA methodology. We use a smartphone application in order to assess anxiety and depression symptoms and coping strategies four times a day during 1 week at three different times after stroke (hospital discharge, 2 and 4 months). Participants' self-reports and clinician-rates of anxiety, depression and coping are collected simultaneously using conventional and standard instruments. Feasibility of the EMA method will be assessed considering the participation and compliance rate. Validity will be the assessed by comparing EMA and conventional self-report and clinician-rated measures. Discussion: We expect this study to contribute to the development of EMA using smartphone in minor stroke population. EMA method offers promising research perspective in the assessment and understanding of post-stroke psychological disorders. The development of EMA in stroke population could lead to clinical implications such as remotely psychological follow-ups during early supported discharge. Trial registration: European Clinical Trials Database Number 2014-A01937-40.

The Hand Motor Hotspot is not Always Located in the Hand Knob: A Neuronavigated Transcranial Magnetic Stimulation Study.

The hand motor hot spot (hMHS) is one of the most salient parameters in transcranial magnetic stimulation (TMS) practice, notably used for targeting. It is commonly accepted that the hMHS corresponds to the hand representation within the primary motor cortex (M1). Anatomical and imaging studies locate this representation in a region of the central sulcus called the "hand knob". The aim of this study was to determine if the hMHS location corresponds to its expected location at the hand knob. Twelve healthy volunteers and eleven patients with chronic neuropathic pain of various origins, but not related to a brain lesion, were enrolled. Morphological magnetic resonance imaging of the brain was normal in all participants. Both hemispheres were studied in all participants except four (two patients and two healthy subjects). Cortical mapping of the hand motor area was conducted using a TMS-dedicated navigation system and recording motor evoked potentials (MEPs) in the contralateral first dorsal interosseous (FDI) muscle. We then determined the anatomical position of the hMHS, defined as the stimulation site providing the largest FDI-MEPs. In 45 % of hemispheres of normal subjects and 25 % of hemispheres of pain patients, the hMHS was located over the central sulcus, most frequently at the level of the hand knob. However, in the other cases, the hMHS was located outside M1, most frequently anteriorly over the precentral or middle frontal gyrus. This study shows that the hMHS does not always correspond to the hand knob and M1 location in healthy subjects or patients. Therefore, image-guided navigation is needed to improve the anatomical accuracy of TMS targeting, even for M1.

Central and peripheral motor drive to the palatal muscles.

AIM OF THE STUDY: To characterize the motor command of the soft palate muscles using a magnetic stimulation technique. MATERIAL AND METHODS: Motor evoked potentials (MEPs) were recorded in 10 right-handed and 5 left-handed subjects at the midline of the palate or on the right or left hemipalate to peripheral and cortical magnetic stimulation. RESULTS: Mean palatal MEP amplitude ranged from 0.06 to 0.26mV to peripheral stimulation and from 0.36 to 1.09mV to cortical stimulation. In hemipalate recordings, MEPs to peripheral stimulation had greater amplitude when recorded ipsilaterally to the stimulation side, whereas MEPs to cortical stimulation were symmetrical. In midline recordings, right-handed subjects showed greater palatal MEP amplitude to right (rather than left) peripheral stimulation and to left (rather than right) cortical stimulation. Mean palatal MEP latency ranged from 4.0 to 4.1ms to peripheral stimulation and from 9.0 to 10.2ms to cortical stimulation; mean central conduction time ranged from 4.9 to 6.2ms. CONCLUSION: Palatal MEPs were easily and reliably obtained, including selective responses in each hemipalate. A bilateral cortical command of the palate is supported by our results, with a possible predominant motor drive from the left hemisphere in right-handed subjects.

Tremor in multiple sclerosis: The intriguing role of the cerebellum.

Tremor is frequently encountered in multiple sclerosis (MS) patients. However, its underlying pathophysiological mechanisms remain poorly understood. Our aim was to assess the potential role of the cerebellum and brain stem structures in the generation of MS tremor.We performed accelerometric (ACC) and electromyographic(EMG) assessment of tremor in 32MS patients with manual clumsiness. In addition to clinical examination, patients underwent a neurophysiological exploration of the brainstem and cerebellar functions,which consisted of blink and masseter inhibitory reflexes, cerebello-thalamo-cortical inhibition (CTCi), and somatosensory evoked potentials. Tremor was clinically visible in 18 patients and absent in 14. Patients with visible tremor had more severe score of ataxia and clinical signs of cerebellar dysfunction, as well as a more reduced CTCi on neurophysiological investigation. However, ACC and EMG recordings confirmed the presence of a real rhythmic activity in only one patient. In most MS patients, the clinically visible tremor corresponded to a pseudorhythmic activity without coupling between ACC and EMG recordings. Cerebellar dysfunction may contribute to the occurrence of this pseudorhythmic activity mimicking tremor during posture and movement execution.

Cortical excitability changes over time in progressive multiple sclerosis.

In 25 patients with progressive forms of multiple sclerosis (MS), motor cortex excitability was longitudinally studied over one year by means of transcranial magnetic stimulation (TMS). The following TMS parameters were considered: resting and active motor thresholds (MTs), input-output curve, short-interval intracortical inhibition (SICI), and intracortical facilitation. Clinical evaluation was based on the Expanded Disability Status Scale (EDSS). In the 16 patients not receiving disease-modifying drugs, the EDSS score worsened, resting MT increased, and SICI decreased. By contrast, no clinical for neurophysiological changes were found over time in the nine patients receiving immunomodulatory therapy. The natural course of progressive MS appears to be associated with a decline in cortical excitability of both pyramidal neurons and inhibitory circuits. This pilot study based on a small sample suggests that disease-modifying drugs may allow cortical excitability to remain stable, even in patients with progressive MS.

Reappraisal of the anatomical landmarks of motor and premotor cortical regions for image-guided brain navigation in TMS practice.

Image-guided navigation systems dedicated to transcranial magnetic stimulation (TMS) have been recently developed and offer the possibility to visualize directly the anatomical structure to be stimulated. Performing navigated TMS requires a perfect knowledge of cortical anatomy, which is very variable between subjects. This study aimed at providing a detailed description of sulcal and gyral anatomy of motor cortical regions with special interest to the inter-individual variability of sulci. We attempted to identify the most stable structures, which can serve as anatomical landmarks for motor cortex mapping in navigated TMS practice. We analyzed the 3D reconstruction of 50 consecutive healthy adult brains (100 hemispheres). Different variants were identified regarding sulcal morphology, but several anatomical structures were found to be remarkably stable (four on dorsoventral axis and five on rostrocaudal axis). These landmarks were used to define a grid of 12 squares, which covered motor cortical regions. This grid was used to perform motor cortical mapping with navigated TMS in 12 healthy subjects from our cohort. The stereotactic coordinates (x-y-z) of the center of each of the 12 squares of the mapping grid were expressed into the standard Talairach space to determine the corresponding functional areas. We found that the regions whose stimulation produced almost constantly motor evoked potentials mainly correspond to the primary motor cortex, with rostral extension to premotor cortex and caudal extension to posterior parietal cortex. Our anatomy-based approach should facilitate the expression and the comparison of the results obtained in motor mapping studies using navigated TMS.

Stroke rehabilitation using noninvasive cortical stimulation: motor deficit.

Noninvasive cortical stimulation (NICS) has been used during the acute, postacute and chronic poststroke phases to improve motor recovery in stroke patients having upper- and/or lower-limb paresis. This paper reviews the rationale for using the different NICS modalities to promote motor stroke rehabilitation. The changes in cortical excitability after stroke and the possible mechanisms of action of cortical stimulation in this context are outlined. A number of open and placebo-controlled trials have investigated the clinical effect of repetitive transcranial magnetic stimulation (rTMS) or transcranial direct current stimulation (tDCS) of the primary motor cortex in patients with motor stroke. These studies attempted to improve motor performance by increasing cortical excitability in the stroke-affected hemisphere (via high-frequency rTMS or anodal tDCS) or by decreasing cortical excitability in the contralateral hemisphere (via low-frequency rTMS or cathodal tDCS). The goal of these studies was to reduce the inhibition exerted by the unaffected hemisphere on the affected hemisphere and to then restore a normal balance of interhemispheric inhibition. All these NICS techniques administered alone or in combination with various methods of neurorehabilitation were found to be safe and equally effective at the short term on various aspects of poststroke motor abilities. However, the long-term effect of NICS on motor stroke needs to be further evaluated before considering the use of such a technique in the daily routine management of stroke.

Stroke rehabilitation using noninvasive cortical stimulation: aphasia.

Poststroke aphasia results from the lesion of cortical areas involved in the motor production of speech (Broca's aphasia) or in the semantic aspects of language comprehension (Wernicke's aphasia). Such lesions produce an important reorganization of speech/language-specific brain networks due to an imbalance between cortical facilitation and inhibition. In fact, functional recovery is associated with changes in the excitability of the damaged neural structures and their connections. Two main mechanisms are involved in poststroke aphasia recovery: the recruitment of perilesional regions of the left hemisphere in case of small lesion and the acquisition of language processing ability in homotopic areas of the nondominant right hemisphere when left hemispheric language abilities are permanently lost. There is some evidence that noninvasive cortical stimulation, especially when combined with language therapy or other therapeutic approaches, can promote aphasia recovery. Cortical stimulation was mainly used to either increase perilesional excitability or reduce contralesional activity based on the concept of reciprocal inhibition and maladaptive plasticity. However, recent studies also showed some positive effects of the reinforcement of neural activities in the contralateral right hemisphere, based on the potential compensatory role of the nondominant hemisphere in stroke recovery.

Stroke rehabilitation using noninvasive cortical stimulation: hemispatial neglect.

The rehabilitation of neuropsychological sequels of cerebral stroke such as hemispatial neglect by noninvasive cortical stimulation (NICS) attracts increasing attention from the scientific community. The NICS techniques include primarily repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS). They are based on the concept of either reactivating a hypoactive cortical region affected by the stroke (the right hemisphere in case of neglect) or reducing cortical hyperactivity of the corresponding cortical region in the contralateral hemisphere (the left hemisphere). In the studies published to date on the topic of neglect rehabilitation, rTMS was used to inhibit the left parietal cortex and tDCS to either activate the right or inhibit the left parietal cortex. Sham-controlled NICS studies assessed short-term effects, whereas long-term effects were only assessed in noncontrolled rTMS studies. Further controlled studies of large series of patients are necessary to determine the best parameters of stimulation (including the optimal cortical target location) according to each subtype of neglect presentation and to the time course of stroke recovery. To date, even if there are serious therapeutic perspectives based on imaging data and experimental studies, the evidence is not compelling enough to recommend any particular NICS protocol to treat this disabling condition in clinical practice.

Congenital agenesis of internal carotid artery with ipsilateral Horner presenting as focal neurological symptoms.

Internal carotid artery (ICA) agenesis is a rare developmental anomaly and is most frequently asymptomatic, but it may also present as cerebrovascular accidents. The association with Horner's syndrome is exceptional. We present three cases of agenesis of ICA associated with Horner's syndrome and hypochromia iridum presenting as focal neurological symptoms. A system of collaterals develops as a consequence of agenesis of the ICA, making the majority of cases asymptomatic. Three types of collateral circulations have been described. These collaterals increase the risk of aneurysm formation and the occurrence of life-threatening subarachnoid hemorrhages. The association of congenital Horner's syndrome and hypochromia iridum without anhidrosis is highly suggestive of sympathetic pathway injury early in life. Such signs should prompt further diagnostic evaluation to demonstrate the presence of the agenesis of the carotid canal. Early diagnosis is essential to rule out potentially life-threatening associated vascular anomalies.