Estimation of central arterial pressure from the radial artery in patients undergoing invasive neuroradiological procedures.

BACKGROUNDS: Central arterial pressure can be derived from analysis of the peripheral artery waveform. The aim of this study was to compare central arterial pressures measured from an intra-aortic catheter with peripheral radial arterial pressures and with central arterial pressures estimated from the peripheral pressure wave using a pressure recording analytical method (PRAM). METHODS: We studied 21 patients undergoing digital subtraction cerebral angiography under local or general anesthesia and equipped with a radial arterial catheter. A second catheter was placed in the ascending aorta for central pressure wave acquisition. Central (AO) and peripheral (RA) arterial waveforms were recorded simultaneously by PRAM for 90-180 s. During an off-line analysis, AO pressures were reconstructed (AOrec) from the RA trace using a mathematical model obtained by multi-linear regression analysis. The AOrec values obtained by PRAM were compared with the true central pressure value obtained from the catheter placed in the ascending aorta. RESULTS: Systolic, diastolic and mean pressures ranged from 79 to 180 mmHg, 47 to 102 mmHg, and 58 to 128 mmHg, respectively, for AO, and 83 to 174 mmHg, 47 to 107 mmHg, and 60 to 129 mmHg, respectively, for RA. The correlation coefficients between AO and RA were 0.86 (p < 0.01), 0.83 (p < 0.01) and 0.86 (p < 0.01) for systolic, diastolic and mean pressures, respectively, and the mean differences - 0.3 mmHg, 2.4 mmHg and 1.5 mmHg. The correlation coefficients between AO and AOrec were 0.92 (p < 0.001), 0.87 (p < 0.001) and 0.92 (p < 0.001), for systolic, diastolic and mean pressures, respectively, and the mean differences 0.01 mmHg, 1.8 mmHg and 1.2 mmHg. CONCLUSIONS: PRAM can provide reliable estimates of central arterial pressure.

Diffusion kurtosis and quantitative susceptibility mapping MRI are sensitive to structural abnormalities in amyotrophic lateral sclerosis.

OBJECTIVE: To construct a clinical diagnostic biomarker using state-of-the-art microstructural MRI in the motor cortex of people with amyotrophic lateral sclerosis (ALS). METHODS: Clinical and MRI data were obtained from 21 ALS patients (aged 54 ±â€¯14 years, 33% female) and 63 age- and gender-matched controls (aged 48 ±â€¯18 years, 43% female). MRI was acquired at 3T and included T1-weighted scan (for volumetrics), arterial spin labelling (for cerebral blood flow), susceptibility-weighted angiography (for iron deposition) and multiband diffusion kurtosis imaging (for tissue microstructure). Group differences in imaging measures in the motor cortex were tested by general linear model and relationships to clinical variables by linear regression. RESULTS: The ALS group had mild-to-moderate impairment (disease duration: 1.8 ±â€¯0.8 years; ALS functional rating scale 40.2 ±â€¯6.0; forced vital capacity 83% ±â€¯22%). No age or gender differences were present between groups. We found significant group differences in diffusion kurtosis metrics (apparent, mean, radial and axial kurtosis: p < .01) and iron deposition in the motor cortex (p = .03). Within the ALS group, we found significant relationships between motor cortex volume, apparent diffusion and disease duration (adjusted R2 = 0.27, p = .011); and between the apparent and radial kurtosis metrics and ALS functional rating scale (adjusted R2 = 0.25, p = .033). A composite imaging biomarker comprising kurtosis and iron deposition measures yielded a maximal diagnostic accuracy of 83% (81% sensitivity, 85% specificity) and an area-under-the-curve of 0.86. CONCLUSION: Diffusion kurtosis is sensitive to early changes present in the motor region in ALS. We propose a composite imaging biomarker reflecting tissue microstructural changes in early ALS that may provide clinically valuable diagnostic information.

Left Thalamus Arteriovenous Malformation Secondary to Radiation Therapy of Original Vermian Arteriovenous Malformation: Case Report.

A 70-year-old gentleman with history of hypothyroidism, hyperlipidemia, hypertension, and right superior cerebellar aneurysm presented to the neurosurgery service in 2008 with vertigo. Diagnostic cerebral angiography performed that year demonstrated a vermian arteriovenous malformations (AVM). The patient underwent stereotactic proton beam radiosurgery, which resulted in a decrease in flow and size of the lesion, and the patient was lost to follow-up. Now at the age of 80, the patient presented with acute gait instability. Cerebral angiogram demonstrated his stable vermian AVM and a new 1.1 cm AVM nidus in the region of the left posterior thalamus. Although AVMs are often described as congenital lesions, there is a growing body of literature suggesting that AVMs can grow, spontaneously regress, and even arise de novo in response to some insult. Understanding what leads to the growth, remodeling, regression, and hemorrhage of AVMs is crucial in order to better direct therapeutic endeavors. We would argue that this patient's AVM is secondary to endothelial cell damage from radiation therapy. Radiation can cause endothelial cell injury and upregulation of factors, such as vascular endothelial growth factor and transforming growth factor beta expression, which are implicated in AVM development pathways. We believe that this patient's new AVM is secondary to entrance radiation dosing affecting the thalamus during radiation therapy for the original vermian AVM.

Deep Venous Thrombosis with Decreased Cerebral Blood Flow to the Thalamus was Completely Restored by Factor Xa Inhibitor.

BACKGROUND: Cerebral venous thrombosis is rare and an uncommon cause of stroke and has diverse etiologies and varied clinical presentations. Here, we report 2 cases of deep cerebral venous thrombosis. CASE DESCRIPTION: A 64-year-old woman presented with cerebral venous thrombosis due to a hypercoagulable state associated with ovarian tumor. On initial fluid-attenuated inversion recovery and diffusion-weighted imaging, there was a diffuse high-intensity lesion in the bilateral thalamus. Computed tomography angiography showed occlusion of the straight sinus, vein of Galen, and internal cerebral vein. Single-photon emission computed tomography showed decreased cerebral blood flow in the bilateral thalamus. After 3 weeks of factor Xa inhibitor therapy, the patient's consciousness gradually improved and eventually became clear enough to leave the hospital. She had no neurological deficit. Another patient was a 47-year-old man who presented with splitting headache and drowsiness. Magnetic resonance venography confirmed deep thrombosis of the vein of Galen. He completely recovered after 4 weeks of factor Xa inhibitor therapy. CONCLUSIONS: This study reports on 2 rare cases of decreased cerebral blood flow in the bilateral thalamus on single-photon emission computed tomography, which improved following the administration of factor Xa inhibitor.

Hybrid Capability to Integrate Multiple Treatment Modalities for Managing High-Grade Intracranial Dural Arteriovenous Fistulas.

BACKGROUND: An integrated multimodality approach can be effective in treatment of high-grade dural arteriovenous fistulas. Nevertheless, this requires a high level of efficient cooperation between different departments, underlying a degree of bias in the decisional process. In comparison, hybrid capability, integrating these modalities in one hand, may allow aggregating multimodality treatment strategies by pooling their individual benefits, leading to a more holistic view of the consequences of each modality. METHODS: We retrospectively reviewed 18 cases of dural arteriovenous fistulas subjected to a hybrid treatment approach at the Diakonieklinikum Jung-Stilling, Siegen, Germany, between March 2008 and January 2017. Nine cases were excluded. We selected 4 cases that highlight different aspects of hybrid capability for illustrative purposes. RESULTS: Hybrid capability allows treatment of a dural arteriovenous fistula based on the individual clinical situation of the patient and features of the lesion, free of interdepartmental bias. The surgeon maintains a level of flexibility that enables him or her to move from a minimally invasive endovascular approach to a maximally invasive surgical access according to the specific situation. Hybrid capability can lead to a highly efficient treatment regimen with palliation of symptoms and complete obliteration of the fistula, improving performance in these complex pathologies. CONCLUSIONS: Hybrid capability has great potential in the treatment of complex neurovascular lesions. It remains to be seen if a single surgeon with hybrid capability can supersede the current multidepartmental practice and achieve better outcomes.

Abnormally high risk of stroke in Brugada syndrome.

BACKGROUND: The present study sought to evaluate the incidence of cerebrovascular events in a large cohort of patients with Brugada syndrome (BrS) analysing possible predictors, clinical characteristics and prognosis of cardioembolic events secondary to atrial fibrillation. METHODS: A total of 671 consecutive patients (age 42.1 ±â€Š17.0 years; men 63%) with a diagnosis of BrS were retrospectively analysed over a mean follow-up period of 10.8 ±â€Š5.5 years. The diagnosis of ischemic stroke was made according to the AHA/ASA guidelines using computed tomography (CT) and angio-CT in the emergency department. RESULTS: Among 671 patients with BrS, 79 (11.8%) had atrial fibrillation. The incidence of cardioembolic stroke in patients with BrS and atrial fibrillation was 13.9% (11 events). These patients had a low CHA2DS2Vasc score (82%, 0 and 1). Patients with transient ischemic attack/stroke were more frequently asymptomatic (91 vs. 25%; P < 0.0001) and older (59.4 ±â€Š11.2 vs. 43.9 ±â€Š16.7; P = 0.004) as compared with those without cerebrovascular events. CONCLUSION: The incidence of cardioembolic stroke in patients with BrS and atrial fibrillation was unexpectedly high. The cerebrovascular accidents were often the presenting clinical manifestation and were significantly associated with asymptomatic atrial fibrillation and older age. CHADS2 and CHA2DS2Vasc scores did not predict the unexpectedly high risk of thromboembolic events in this group of patients. The use of more invasive diagnostic tools might be useful in order to increase the rate of atrial fibrillation detection.

The Value of Exercise Rehabilitation Program Accompanied by Experiential Music for Recovery of Cognitive and Motor Skills in Stroke Patients.

BACKGROUND: The aim of this study was to systematically assess the effects of exercise rehabilitation program accompanied by experiential music for clinical recovery. METHODS: This was a prospective randomized study with 65 stroke survivor patients. All cases underwent a neuropsychological assessment first as a prescreening test, during the admission at the Rehabilitation center (baseline), and 6 months poststroke. All patients received standard treatment for stroke in terms of medical care and rehabilitation. Additionally, all patients were separated into 2 Groups: a music Group (daily listening to experiential/traditional music), and a control Group (CG) with no experiential/traditional music therapy (standard care only). Computed tomography perfusion and full neurological examination including GCS were assessment. As Recovery was defined the improvement of cognitive and motor skills of the limb in the affected site, with an increase of muscle strength at least by 1/5 and with emotional progress. RESULTS: Statistically significant differences were found between the Group CG and the rest of the patients in respect of Lesion size (P = .001) and CBF in affected area (P = .001). Μultivariate analysis revealed that only Group and Lesion size were independent predictors for Recovery (odd ratio [OR][95%confidence interval]) .11(.001-.133) and .798(.668-.954) respectively. CONCLUSION: The findings of this study suggest that the music-based exercise program has a positive effect on mood profile in stroke patients and Recovery rate is higher when exercise rehabilitation program was accompanied by an enriched sound environment with experiential music.

A Rare Complication of Sarcoidosis.

BACKGROUND: Cerebral vasculitis is a serious, but uncommon inflammatory condition of the blood vessel walls, with an annual incidence of 1-2 per million. A variety of disorders including encephalopathy, stroke, seizure, acute or subacute focal deficits should be considered as a differential diagnosis. CLINICAL CASE: A 56-year old male with a past history of pulmonary sarcoid presented with a unilateral facial numbness and loss of balance arising during sleep. His computed tomography scan of the brain was normal but brain magnetic resonance imaging with gadolinium demonstrated scattered infarcts in mixture of stroke topography not purely in keeping with embolism nor intrinsic small vessel disease. Further investigations including carotid ultrasound, transthoracic echo and 24-hour electrocardiogram were within normal limits. However, computed tomography angiography showed evidence of a widespread intracranial vasculopathy, as well as evidence of dissection of the left common carotid artery. His elevated calcium was consistence with a sarcoidosis relapse and cerebrospinal fluid analysis was in keeping with a central nervous system inflammatory process. Treatment was commenced with high dose steroids with additional pulsed intravenous cyclophosphamide together with antiplatelet therapy and a statin. CONCLUSIONS: This case illustrates the intracranial vasculopathy as a rare complication of sarcoidosis. Although sarcoid is well recognized to affect the central nervous system, it is unusual in the form of cerebral vasculitis.

Drip-and-Ship Thrombolytic Therapy for Acute Ischemic Stroke.

BACKGROUND: Neuroendovascular therapy is a common treatment for patients with acute ischemic stroke of the anterior circulation who fail to respond to recombinant tissue plasminogen activator. However, although most hospitals can provide recombinant tissue plasminogen activator therapy, many cannot perform neuroendovascular therapy. Thus, use of a drip-and-ship treatment-liaison system allowing recombinant tissue plasminogen activator-treated patients to be transferred to facilities offering neuroendovascular therapy is important. METHODS: We retrospectively analyzed 16 drip-and-ship patients transferred to our hospital for additional neuroendovascular therapy after they received intravenous recombinant tissue plasminogen activator at prior hospitals between June 2009 and March 2017. RESULTS: The mean patient age was 68 ± 17 years. Ten patients had cardiogenic embolism and 6 had atherothrombosis. Additional neuroendovascular therapy was performed in 14 patients. Median National Institute of Health Stroke Scale and diffusion-weighted image-Alberta Stroke Program Early Computed Tomography Scores before recombinant tissue plasminogen activator therapy were 14 and 8, respectively. Occluded or stenotic lesions of the cerebral arteries were detected by magnetic resonance angiography in the internal carotid artery (n = 4), middle cerebral artery (n = 10), and basilar artery (n = 3) (1 patient had tandem lesions). Mean intervals from onset-to-recombinant tissue plasminogen activator, recombinant tissue plasminogen activator-to-our hospital (door), door-to-puncture, and onset-to-recanalization were 166, 65, 32, and 334 minutes, respectively. No patients showed symptomatic intracranial hemorrhage. CONCLUSIONS: Magnetic resonance imaging/angiography performed in previous hospitals allows initiation of reperfusion therapy immediately after transfer. Thus, drip-and-ship plus neuroendovascular therapy is a safe and useful system for treatment of patients with acute infarcts.

Artery of Percheron Infarct: ARarity Not to be Missed.

Artery of Percheron (AOP) is a rare vascular variant of posterior cerebral circulation and it supplies blood to the bilateral paramedian thalami and the rostral midbrain. Artery of Percheron infarct requires a comprehensive clinical and radiological examination. It can be easily overlooked due to normal CTfindings and wide range of differential diagnosis. Classic triad of presentation is altered mental status, memory impairment and the vertical gaze palsy. We report a case of a 66-year female who had sudden onset of severe vertigo, diplopia and ataxia. Anon-contrast CTBrain was performed which was normal. Her MRI brain with diffusion weighted images (DWI) confirmed bilateral thalamic infarcts which were initially thought to be calcifications, as usually happens with diagnosing artery of Percheron infarcts. However, by reviewing and ruling out all other possible causes of such symptoms and further review of neuroimaging, lead us to the correct diagnosis.

Efficacy of New Measures Saving Time in Acute Stroke Management: A Quantified Analysis.

BACKGROUND: Time to treatment remains the most important factor in acute ischemic stroke prognosis. We quantified the effect of new interventions reducing in-hospital delays in acute stroke management and assessed its repercussion on door-to-imaging (DTI), imaging-to-needle (ITN), and door-to-needle (DTN) times. METHODS: Prospective registry of consecutive stroke patients who were candidates for reperfusion therapy attended in a tertiary care hospital from February 1 to December 31, 2014. A series of measures aimed at reducing in-hospital delays were implemented. We compared DTI, ITN, and DTN times between patients who underwent the interventions and those who did not. RESULTS: 231 patients. DTI time was lower when personal history was reviewed and tests were ordered before patient arrival (2.5 minutes saved, P = .016) and when electrocardiogram was not made (5.4 minutes saved, P < .001). Not performing a computed tomography angiography and not waiting for coagulation results from laboratory before intravenous thrombolysis (25.5%) reduced ITN time significantly (14 and 12 minutes saved, respectively, P < .001). These interventions remained as independent predictors of a shorter ITN and DTN time. Completing all steps resulted in the lowest DTI and ITN times (13 and 19 minutes, respectively). CONCLUSIONS: Every measure is an important part of a chain focused on saving time in acute stroke: the lowest DTI and ITN times were obtained when all steps were completed. Measures shortening ITN time produced a greater impact on DTN time reduction; therefore, ITN interventions should be considered a critical part of new protocols and guidelines.

Collaborative Interventions Reduce Time-to-Thrombolysis for Acute Ischemic Stroke in a Public Safety Net Hospital.

BACKGROUND AND PURPOSE: Shorter time-to-thrombolysis in acute ischemic stroke (AIS) is associated with improved functional outcome and reduced morbidity. We evaluate the effect of several interventions to reduce time-to-thrombolysis at an urban, public safety net hospital. METHODS: All patients treated with tissue plasminogen activator for AIS at our institution between 2008 and 2015 were included in a retrospective analysis of door-to-needle (DTN) time and associated factors. Between 2011 and 2014, we implemented 11 distinct interventions to reduce DTN time. Here, we assess the relative impact of each intervention on DTN time. RESULTS: The median DTN time pre- and postintervention decreased from 87 (interquartile range: 68-109) minutes to 49 (interquartile range: 39-63) minutes. The reduction was comprised primarily of a decrease in median time from computed tomography scan order to interpretation. The goal DTN time of 60 minutes or less was achieved in 9% (95% confidence interval: 5%-22%) of cases preintervention, compared with 70% (58%-81%) postintervention. Interventions with the greatest impact on DTN time included the implementation of a stroke group paging system, dedicated emergency department stroke pharmacists, and the development of a stroke code supply box. CONCLUSIONS: Multidisciplinary, collaborative interventions are associated with a significant and substantial reduction in time-to-thrombolysis. Such targeted interventions are efficient and achievable in resource-limited settings, where they are most needed.

Complex neurological symptoms in bilateral thalamic stroke due to Percheron artery occlusion.

The artery of Percheron is a rare anatomical variant where a single thalamic perforating artery arises from the proximal posterior cerebral artery (P1 segment) between the basilar artery and the posterior communicating artery and supplies the rostral mesencephalon and both paramedian territories of the thalami. Almost one-third of human brains present this variant. Occlusion of the artery of Percheron mostly results in a bilateral medial thalamic infarction, which usually manifests with altered consciousness (including coma), vertical gaze paresis, and cognitive disturbance. The presentation is similar to the "top of the basilar syndrome", and early recognition should be prompted. We describe the case of a young female with this vessel variant who experienced a bilateral thalamic stroke. Magnetic resonance angiography demonstrated bilateral thalamic infarcts and a truncated artery of Percheron. Occlusion of the vessel was presumably due to embolism from a patent foramen ovale. Thrombolysis was performed, with incomplete symptom remission, cognitive impairment, and persistence of speech disorders. Early recognition and treatment of posterior circulation strokes is mandatory, and further investigation for underlying stroke etiologies is needed.

The Posterior Limb of the Internal Capsule as the Subcortical Transitional Zone of the Anterior and Posterior Circulations: Insights from Human 7T MRI.

BACKGROUND: In patients with cerebral infarction, identifying the distribution of infarction and the relevant artery is essential for ascertaining the underlying vascular pathophysiological mechanisms and preventing subsequent stroke. However, visualization of the basal perforating arteries (BPAs) has had limited success, and simultaneous viewing of background anatomical structures has only rarely been attempted in living human brains. Our study aimed at identifying the BPAs with 7T MRI and evaluating their distribution in the subcortical structures, thereby showing the clinical significance of the technique. METHODS: Twenty healthy subjects and 1 patient with cerebral infarction involving the posterior limb of the internal capsule (ICpost) and thalamus underwent 3-dimensional fast spoiled gradient-echo sequence as time-of-flight magnetic resonance angiography (MRA) at 7T with a submillimeter resolution. The MRA was modified to detect inflow signals from BPAs, while preserving the background anatomical signals. BPA stems and branches in the subcortical structures and their origins were identified on images, using partial maximum intensity projection in 3 dimensions. RESULTS: A branch of the left posterior cerebral artery (PCA) in the patient ran through both the infarcted thalamus and ICpost and was clearly the relevant artery. In 40 intact hemispheres in healthy subjects, 571 stems and 1,421 branches of BPAs were detected in the subcortical structures. No significant differences in the numbers of stems and branches were observed between the intact hemispheres. The numbers deviated even less across subjects. The distribution analysis showed that the subcortical structures of the telencephalon, such as the caudate nucleus, anterior limb of the internal capsule, and lenticular nucleus, were predominantly supplied by BPAs from the anterior circulation. In contrast, the thalamus, belonging to the diencephalon, was mostly fed by BPAs from the posterior circulation. However, compared with other subcortical structures, the ICpost, which marks the anatomical boundary between the telencephalon and the diencephalon, was supplied by BPAs with significantly more diverse origins. These BPAs originated from the internal carotid artery (23.1%), middle cerebral artery (38.5%), PCA (17.3%), and the posterior communicating artery (21.1%). CONCLUSIONS: The modified MRI method allowed the detection of the relevant BPA within the infarcted area in the stroke survivor as well as the BPAs in the subcortical structures of living human brains. Based on in vivo BPA distribution analyses, the ICpost is the transitional zone of the anterior and posterior cerebral circulations.

Predicting stroke outcome using clinical- versus imaging-based scoring system.

BACKGROUND: Several models to predict outcome in ischemic stroke patients receiving intravenous (i.v.) alteplase can be divided into clinical-based and imaging-based systems. Alberta Stroke Program Early Computed Tomography (CT) Score (ASPECTS) and Dense cerebral artery sign/early infarct signs on admission CT scan, prestroke modified Rankin Scale (mRS) score, Age, Glucose level at baseline, Onset-to-treatment time, and baseline National Institutes of Health Stroke Scale score (DRAGON) are typical imaging- and clinical-based scoring systems, respectively. Therefore, we compared predictability of stroke outcome of clinical (DRAGON)- and imaging (ASPECTS)-based scoring systems. METHODS: We analyzed patients who were diagnosed with middle cerebral artery territory stroke and treated with i.v. alteplase at Gachon University Gil Hospital over 5 years and compared performance of 2 scoring systems for prediction of good functional outcome (mRS, 0-2) with Pearson correlation and area under the curve-receiver operating characteristic (AUC-ROC). In addition, we analyzed predicting power of several clinical factors and 2 scoring systems by multiple regression analysis. RESULTS: Study population (N = 120) had mean age of 66.2 ± 13.2 years. ASPECTS (r = -.841, P < .0001) and DRAGON (r = .657, P < .0001) were significantly correlated with good functional outcome. In addition, statistical comparisons suggested that ASPECTS (AUC-ROC, .972; 95% confidence interval [CI], .947-.996) is significantly superior to DRAGON (AUC-ROC, .854; 95% CI, .786-.922) in predicting functional outcome (difference between areas, .118 ± .0332; 95% CI, .0559-.180, P = .0002). Multiple regression analysis revealed that ASPECTS was the independent predictor of good prognosis (OR, 6.59 per 1-point increase; 95% CI, 2.35-18.49; P < .0001 and OR, 77.67 for ASPECTS ≥ 8; 95% CI, 14.30-421.79; P < .0001). CONCLUSIONS: ASPECTS is superior method for predicting functional outcome in acute ischemic stroke patients receiving i.v. alteplase compared with DRAGON and integration of ASPECTS score into clinical care pathway as decision-making tool can be reasonable.

Intravenous thrombolysis with recombinant tissue plasminogen activator in a stroke patient treated with rivaroxaban.

As limited amounts of data are available regarding thrombolytic therapy for patients taking novel oral anticoagulants, thrombolytic therapy is not recommended in such cases. Here, we report an acute stroke patient taking rivaroxaban who received intravenous thrombolysis with recombinant tissue plasminogen activator (rt-PA). An 80-year-old man with a history of nonvalvular atrial fibrillation, who had been receiving 10 mg of rivaroxaban showed abrupt onset of aphasia and right hemiparesis. National Institutes of Health Stroke Scale score was 10. Onset of neurologic deficits occurred 4 hours after the last dose of rivaroxaban. Clinical data on admission were as follows: blood pressure, 170/90 mm Hg; prothrombin time (PT), 22.6 seconds (control, 12.9 seconds); international normalized ratio, 2.03; activated partial thromboplastin time, 46 seconds (normal, 23-32 seconds); and creatinine level, 1.11 mg/dL. Magnetic resonance angiography revealed occlusion of the superior trunk of the left middle cerebral artery. Intravenous infusion of .6 mg/kg of rt-PA (total dose, 36 mg) was performed 6 hours after the last rivaroxaban administration with informed consent. The neurologic deficit improved during infusion of rt-PA. Repeat brain computed tomography showed left frontal cortical infarction without hemorrhagic changes. In the case of rivaroxaban, it is difficult to accurately determine the drug activity. As the anticoagulant activity of rivaroxaban can be estimated from its pharmacokinetics and PT, it is clinically important to obtain accurate information about the timing of medication and blood sampling.

Clinical spectrum of artery of Percheron infarct: clinical-radiological correlations.

BACKGROUND: The occlusion of the artery of Percheron results in bilateral thalamic and mesencephalic infarctions. In this series, we attempted to classify the subtypes of clinical presentations and long-term prognosis with regards to radiological patterns. METHODS: We sought the clinical and radiological findings of 15 (8 men and 7 women; mean age 48 years) consecutive patients with Percheron artery infarct over 10 years. We classified the clinical symptoms according to the presence of a mental status disturbance (MSD), behavioral amnesic impairment (BAI), aphasia/dysarthria, ocular movement disorders (OMDs), motor deficit, cerebellar signs, and others. The Percheron artery infarct images were classified as bilateral paramedian thalamic with rostral midbrain infarction (BPTRMI), bilateral paramedian thalamic without midbrain infarction (BPTWMI), bilateral paramedian and anterior thalamic with midbrain infarction (BPATMI), and bilateral paramedian and anterior thalamic without midbrain infarction. The outcome was evaluated using a modified Rankin Scale (mRS). RESULTS: OMD and MSD were the most common clinical manifestations in patients with BPTRMI (n = 8). BAI and MSD were the main clinical findings in patients with BPTWMI (n = 6). A patient with BPATMI had a combination of clinical manifestations. After a mean follow-up of 55 months, a good outcome (mRS score ≤ 2) was present in 25% of the patients with BPTRMI, 67% of the patients with BPTWMI, and in 1 patient with BPATMI. CONCLUSIONS: Our findings suggest that it is possible to identify clinical and radiological subgroups of Percheron artery infarct. The long-term follow-up outcome is generally good, except in cases with midbrain involvement.

Anatomical variations in the posterior part of the circle of willis and vascular pathology in bilateral thalamic infarction.

BACKGROUND AND PURPOSE: Bilateral paramedian thalamic infarction is a rare subtype of stroke the etiology of which still remains undetermined in many patients. METHODS: From a computed tomography (CT)/magnetic resonance imaging report database, we identified and analyzed 48 patients with bilateral paramedian thalamic infarction on diffusion-weighted imaging. Vascular pathologies were noted on CT angiography (CTA)/magnetic resonance angiography (MRA) and the P1 segments of the posterior cerebral artery (PCA) described as normal, hypoplastic, or absent. RESULTS: Vascular imaging revealed top of the basilar artery (BA) occlusion in 6 (12.5%), BA occlusion in 4 (8.3%), BA stenosis in 1 (2.1%), and BA hypoplasia in 3 (6.3%), PCA occlusion in 4 (8.3%), and PCA stenosis in 4 (8.3%) patients. In 18 (37.5%) patients, one or both P1 segments of the PCA were hypoplastic or absent. Patients with hypoplastic/absent P1 segments were more likely to have exclusively bilateral paramedian thalamic lesions (P < .001). An embolic source could be identified in 25 (55.6%) patients; there were no significant differences between both groups. CONCLUSIONS: Vascular imaging is useful to determine underlying vascular pathologies and may support the diagnosis of small vessel disease in those patients with isolated bilateral paramedian thalamic infarction, hypoplastic/absent P1 segment of the PCA, and lack of vascular pathology.