bluuebunny/crossref_metadata_2025_split huggingface dataset:
Association of Pretreatment ASPECTS Scores with tPA‐Induced Arterial Recanalization in Acute Middle Cerebral Artery Occlusion
Authors: Tsivgoulis Georgios , Saqqur Maher , Sharma Vijay K. , Lao Annabelle Y. , Hoover Steven L. , Alexandrov Andrei V. ,   for the CLOTBUST Investigators
Published: October 2009

ABSTRACTBACKGROUND AND PURPOSE The Alberta Stroke Program Early CT‐Score (ASPECTS) assesses early ischemic changes within the middle cerebral artery (MCA) and predicts poor outcome and increased risk for thrombolysis‐related symptomatic ICH. We evaluated the potential relationship between pretreatment ASPECTS and tPA‐induced recanalization in patients with MCA occlusions. SUBJECTS & METHODS Consecutive patients with acute ischemic stroke due to MCA occlusion were treated with standard IV‐tPA and assessed with transcranial Doppler (TCD) for arterial recanalization. Early recanalization was determined with previously validated Thrombolysis in Brain Ischemia (TIBI) flow‐grading system at 120 minutes after tPA‐bolus. All pretreatment CT‐scans were prospectively scored by trained investigators blinded to TCD findings. Functional outcome at 3 months was evaluated using the modified Rankin Scale (mRS). RESULTSIV‐tPA was administered in 192 patients (mean age 68 ± 14 years, median NIHSS‐score 17). Patients with complete recanalization (n= 51) had higher median pretreatment ASPECTS (10, interquartile range 2) than patients with incomplete or absent recanalization (n= 141; median ASPECTS 9, interquartile range 3, P= .034 Mann‐Whitney U‐test). An ASPECTS ≤6 was documented in 4% and 17% of patients with present and absent recanalization, respectively (P= .019). Pretreatment ASPECTS was associated with complete recanalization (OR per 1‐point increase: 1.54; 95% CI 1.06–2.22, P= .023) after adjustment for baseline characteristics, risk factors, NIHSS‐score, pretreatment TIBI grades and site of arterial occlusion on baseline TCD. Complete recanalization (OR: 33.97, 95% CI 5.95–185.99, P < .001) and higher ASPECTS (OR per 1‐point increase: 1.91; 95% CI 1.17–3.14, P= .010) were independent predictors of good functional outcome (mRS 0–2).CONCLUSIONS Higher pretreatment ASPECT‐scores are associated with a greater chance of complete recanalization and favorable long‐term outcome in tPA‐treated patients with acute MCA occlusion.
Quantitative Magnetic Resonance Angiography of the Cerebrovasculature in Physiologic and Pathologic States
Authors: Conway Stafford A. , Bowling Susana M. , Geyer James D. , Potts Daniel C. , Clemons Brett L. , Gomez Camilo R. 
Published: October 2009

ABSTRACTBACKGROUND In the past, clinical decisions regarding treatment of neurovascular disorders leading to ischemia have been guided by the percentage of stenosis of the vessel in question. However, such an approach assumes a predictable and stable relationship between the percentage of stenosis and the degree of flow reduction it causes. Historically, this type of relationship has been difficult to document. Thus, a method for noninvasively measuring the absolute flow of specific cerebral arteries is of potential practical value. METHODS We set to quantify the mean blood flow (Qm, in mL/min) in the cerebral arteries using quantitative magnetic resonance angiography (QMRA), and to compare the findings in normal vessels with those found in vessels considered pathologically narrowed. Specific vascular segments were identified, studied, and the results entered into a database. Statistical analyses of the measurements were carried out using StatPlus for Microsoft Excel. It involved comparing of the Qm found in specific vessels, as well as those found in normal and abnormal vessels, using analysis of variance (ANOVA). The abnormal vessels were selected from specifically identified magnetic resonance angiography (MRA) studies. RESULTS A total of 57 patients, 26 men and 31 women, with ages ranging from 19 to 86 years (mean = 64.5), underwent MRA with subsequent QMRA of 157 arteries. The latter included 72 internal carotid (ICA), 45 vertebral (VA), 18 common carotid (CCA), 13 middle cerebral (MCA), and nine basilar (BA) arteries. The mean Qm obtained were CCA = 313.9 (±115.4), ICA = 231.1 (±83.7), VA = 90.5 (±45.8), MCA = 92.5 (±62.3) and BA = 120.1 (±64.5). ANOVA showed significant differences between individual vessels (P < .00001). The values obtained were consistent with those predicted mathematically, as derivatives of their proportional contributions to overall cerebral arterial flow (Qbrain) as a product of the normal cardiac output (CO) [ie, Qbrain = CO*.2]. Further ANOVA of the normal and abnormal vessels showed statistically significant differences between the two groups (186.5 ± 108.6 vs. 117.9 ± 76.1, respectively; P= .000514). CONCLUSIONS The use of QMRA provides the mean for direct measurement of absolute blood flow within the cerebral arteries in physiologic and pathologic states. This technique may be of future importance in characterizing absolute flow compromise in the cerebral arteries under a variety of clinically relevant circumstances.
Ultrasonic Radio‐Frequency Spectrum Analysis Differentiates Normal and Edematous Brain Tissue from Meningioma Intraoperatively
Authors: Strowitzki Martin , Brand Sebastian , Ketter Ralf , Steudel Wolf Ingo , Jenderka Klaus‐Vitold 
Published: October 2009

ABSTRACTIntraoperative ultrasound imaging of the brain is used for tumor localization and resection control. The aim of the present study was to prove whether spectral analysis of radio‐frequency (rf) signals is able to improve its diagnostic capabilities by adding quantitative acoustical parameters to pure visual analysis. Meningioma was chosen as a first model because of its distinct borders during surgery as well as in ultrasound imaging. Rf signals were captured intraoperatively. Spectral analysis of rf signals was performed off‐line in areas of normal brain, edematous tissue, and meningioma within the bandwidth of the transducer. At 5.0 MHz, attenuation allowed significant differentiation for normal brain versus edema (P= .00002), normal brain versus meningioma (P= .000004), and edema versus meningioma (P= .002). The slope of attenuation reached significant levels among the three groups, too. Backscatter analysis consisted of determination of the power spectral density with a significant difference for edema versus meningioma at 5 MHz (P= .02). The same was true for a relative integrated backscatter coefficient (P= .01). Frequency‐dependent backscatter coefficients were estimated using a standard phantom with edema showing the highest values followed by parenchyma and meningioma. Spectral analysis of rf signals has the potential of differentiating intracranial tissues as could be shown exemplarily with meningioma in this study. If this is also true for infiltrating tumors, the method might serve as a tool to better define tumor borders, thus improving the extent of resection.
Identification of the Sensorimotor Cortex with Functional MRI: Frequency and Actual Contribution in a Neurosurgical Context
Authors: Pujol Jesus , Deus Joan , Acebes Juan J. , Villanueva Alicia , Aparicio Alberto , Soriano‐Mas Carles , Ortiz Hector , Conesa Gerardo 
Published: October 2009

ABSTRACTBACKGROUND AND PURPOSE We assessed the actual frequency of motor functional MRI (fMRI) in a neurosurgical environment and estimated the extent to which it aided surgeons' identifications of the sensorimotor cortex. METHODS During five consecutive years, an fMRI protocol aimed at generating a selective activation of the hand cortical area was prescribed to 147 patients showing a centrally located space‐occupying lesion, which represents 6.7% of all assisted surgical candidates showing an intracranial mass. Three senior neurosurgeons indicated the position of the sensorimotor cortex on two different anatomical displays, reporting confidence ratings for each decision. RESULTS The sensorimotor cortex could not be identified in 16.5% of cases using conventional anatomical MRI, and in 15% of cases using 3‐dimensional reconstructions. In an additional 12.5% of cases, the neurosurgeons were not confident when they correctly identified the sensorimotor cortex. The tumor distorting effect on central region anatomy significantly contributed to sensorimotor cortex misidentification. fMRI, by contrast, showed a selective activation indicating the position of the sensorimotor cortex in all but 4% of cases. CONCLUSIONS In our neurosurgical environment, fMRI was prescribed to a selected group of surgical candidates showing a centrally located brain lesion. Compared to conventional anatomical imaging, fMRI does appear to improve the identification of sensorimotor cortex.
Rotational Vertebrobasilar Insufficiency Due to Dynamic Compression of the Dominant Vertebral Artery by the Thyroid Cartilage and Occlusion of the Contralateral Vertebral Artery at C1–2 Level
Authors: Dabus Guilherme , Gerstle Ronald J. , Parsons Matthew , Cross DeWitte T. , Moran Christopher J. , Thompson Robert , Derdeyn Colin P. 
Published: October 2009

ABSTRACTBACKGROUND Vertebrobasilar insufficiency caused by head rotation is an uncommon event. The mechanism is obstruction of the vertebral artery resulting in flow limitation or, less frequently, thromboembolism. CASE DESCRIPTION A 41‐year‐old male developed dizziness and light‐headedness during chiropractic manipulation when his head was turned to the extreme right position. Computed tomography angiography (CTA) of the neck and selective digital subtraction angiography (DSA) of the vertebral arteries revealed that when the patient turned his head to the extreme right position the dominant right vertebral artery was compressed between the posterior aspect of the thyroid cartilage and anterior aspect of the right transverse process of C6 resulting in focal stenosis, while the left vertebral artery is severely compressed with significant flow limitation at the level of C1–2. Because the patient was healthy and asymptomatic, conservative management was adopted. At the 9‐month follow‐up visit the patient was asymptomatic and able to compensate for his problem avoiding turning his head to the extreme right position. CONCLUSIONS We present an uncommon case of rotational vertebrobasilar insufficiency (VBI) where the dominant vertebral artery has an anomalous course compressed by the thyroid cartilage at C6 level, associated with contralateral vertebral artery rotational stenosis at C1–2. The patient was successfully managed conservatively.
Early Spontaneous Recanalization Following Acute Carotid Occlusion
Authors: Szabo Kristina , Kern Rolf , Gass Achim , Griebe Martin , Lanczik Oliver , Daffertshofer Michael , Hennerici Michael G. 
Published: October 2009

ABSTRACTBACKGROUND AND PURPOSE Occlusion of the internal carotid artery (ICA) and stroke may be the consequence of either local thrombosis due to atherosclerosis or massive embolism. Up to date, there are only few reports of subsequent recanalization. METHODS We report 12/76 cases of acute ICA occlusion leading to ischemic stroke, in which early recanalization was identified. Ultrasound and stroke MRI findings, therapeutic options, and outcome are described. RESULTS 10/12 patients showed an‐ or hypoechogenic morphology of occlusion. While in 7/12 cases complete recanalization was seen, in 5/12 patients partial recanalization with filiform flow (4) or residual high‐grade stenosis (1) was detected. 10/12 patients had territorial or subcortical infarction, while two showed small cortical lesions only. In 7/12 cases, a potential cardiac source of embolism was found. Five patients received tPA; four patients underwent early carotid endarterectomy of the partially recanalized ICA within 48 hours. In the 10‐day follow‐up examination 10/12 patients showed clinical improvement as measured by the NIHSS.CONCLUSIONS Spontaneous recanalization after occlusion of the ICA may occur and might be more frequent than hitherto assumed. Echogenicity analysis and serial examinations of symptomatic ICA occlusion is useful for identifying a patient subgroup that might benefit from further therapy.
Functional Imaging of Stroke Recovery: An Ecological Review from a Neural Network Perspective with an Emphasis on Motor Systems
Authors: Erik Ween Jon 
Published: October 2009

ABSTRACTFunctional imaging is beginning to outline the brain's functional architecture and mechanisms of recovery from injury. I will review primarily the motor‐function literature from normal populations, learning trials, stroke recovery, and rehabilitation with a neural network approach that may prove fruitful in further advancing our understanding of brain plasticity in response to focal lesions. A key consideration in this review will be how the development of distributed motor networks might constrain recovery as a function of the altered connectivity between damaged and nondamaged areas. It will be argued that this connectivity is central to both recovery from injury and response to treatment.
Clinical‐Sonographic Index (CSI): A Novel Transcranial Doppler Diagnostic Model for Middle Cerebral Artery Stenosis
Authors: Jung Keun‐Hwa , Lee Yong‐Seok 
Published: October 2009

ABSTRACTBACKGROUND Transcranial Doppler sonography is useful for the diagnosis of middle cerebral artery (MCA) stenosis. Although the previous studies have focused on the elevated mean flow velocity (MFV) or asymmetry of MFV, the lack of clinical correlation might limit diagnostic accuracy. We try to develop and validate a new diagnostic model including more comprehensive clinical and sonographic parameters. METHODS Consecutive patients with magnetic resonance angiography (MRA)‐verified MCA stenosis were included, and compared with control subjects with normal MCA. The age, sex, corresponding symptoms (CS) to sonographic side, diabetes mellitus (DM), and hypertension were included for analysis. As sonographic parameters, MFV (cm/sec), asymmetry index (AI,%), and difference of pulsatility index (ΔPI) were analyzed. Clinical‐sonographic index (CSI) model was built with significant parameters by multivariate logistic regression analysis. RESULTS One hundred and seven patients (

M:F = 53:54
, age: 61.6 ± 11.6 years), and 100 control subjects (M:F = 49:51, age: 54.9 ± 14.5 years) were included. In logistic regression, MFV (odds ratio [OR], 1.057; 95% confidence interval [95% CI], 1.030–1.084), AI (OR, 1.067; 95% CI, 1.031–1.104), ΔPI (OR, 41.754; 95% CI, 2.771–626.999), CS (OR, 15.904; 95% CI, 5.055–50.042), and DM (OR, 3.949; 95% CI, 1.132–13.783) were independent predictors of MCA stenosis. CSI was simplified for clinical use, CSI = MFV(cm/sec) + 3 * AI (%) + 180 *ΔPI + 90 * CS(presence = 1, absence = 0) + 30 * DM (presence = 1, absence = 0). The area under the receiver operator characteristic (ROC) curve of MCA stenosis versus MFV, ΔPI, AI, and CSI was .641, .668, .865 and .953. According to ROC curve, cut‐off point for MCA stenosis was suggested as CSI > 180 (sensitivity: 87%, specificity: 92%).CONCLUSION CSI might be useful to enhance diagnostic accuracy.
Dual Origin Extracranial Vertebral Artery: Case Report and Embryology
Authors: Thomas Ajith J. , Germanwala Anand V. , Vora Nirav , Prevedello Daniel M. , Jovin Tudor , Kassam Amin , Horowitz Michael 
Published: October 2009

ABSTRACT Duplication of the vertebral artery origin is a rare vascular anomaly. The authors describe this finding in a patient who underwent neurointerventional treatment for a midbasilar aneurysm. The embryology and clinical significance is also presented.
Cerebral Changes in SLE With or Without Antiphospholipid Syndrome. A Case‐Control MRI Study
Authors: Valdés‐Ferrer Sergio I. , Vega Felipe , Cantú‐Brito Carlos , Ceballos‐Ceballos Joel , Estañol Bruno , García‐Ramos Gullermo , Cabral Antonio R. 
Published: October 2009

ABSTRACTBACKGROUND To determine and characterize the prevalence of cerebral changes on MRI in patients with antiphospholipid syndrome (APLS) within systemic lupus erythematosus (SLE). METHODS Seventy‐one patients with SLE were prospectively studied with brain MRI: 32 with definite APLS and 39 without. Atrophy, ventricular enlargement, leukoaraiosis, interuncal distance, Evans' index, infarcts, and white matter hyperintensities (WMH) were analyzed. Demographic data, treatment, and SLE activity were analyzed. RESULTS Groups were similar in age (32.4 vs. 32.8 years old; P= non‐significant [NS]), and gender. Duration of disease was longer in patients with APLS (87.3 vs. 55.4 months; P= .064). Cortical atrophy was common in both groups (68.7% vs. 89.7%; P= NS). Leukoaraiosis was present in only 3 patients (9.4%; P= .08), all in the APLS group. WMH were found in more than 40% of the patients from both groups. Infarcts (21.9% vs. 2.6%; P= .019) and infarcts plus WHM (12.5% vs. 0; P= .037) were more common in patients with APLS. CONCLUSIONS Although a higher prevalence of neurological involvement in SLE has been reported in APLS patients, we found gross brain changes to be similar between groups. Strokes and leukoaraiosis were more common in the APLS group, consistent with the idea of an APLS‐induced prothrombotic state.
Postprocedure Intravenous Eptifibatide Following Intra‐Arterial Reteplase in Patients with Acute Ischemic Stroke
Authors: Qureshi Adnan I. , Hussein Haitham M. , Janjua Nazli , Harris‐Lane Pansy , Ezzeddine Mustapha A. 
Published: October 2009

ABSTRACTBACKGROUND AND PURPOSEEarly use of intravenous platelet glycoprotein IIB/IIIA antagonists after intra‐arterial (IA) thrombolysis may reduce the risk of reocclusion and microvascular compromise.METHODSWe performed a retrospective study to determine the in‐hospital outcomes using serial neurological evaluations and imaging among patients treated with intravenous eptifibatide administered as a 135 microg/kg single‐dose bolus, followed by 0.5 microg/kg/min infusions for 20 to 24 hours following treatment with IA reteplase.RESULTSTwenty patients were treated (mean age ± standard deviation, 68.4 ± 14.5 years; median National Institutes of Health Stroke Scale [NIHSS] score was 17). The dose of reteplase ranged from 0.5 to 4 units. Eleven patients demonstrated early neurological improvement, defined as a decline of ≥4 points on the 24 hours NIHSS score compared with initial NIHSS score; neurological deterioration, defined as an increase of ≥4 points on the 24 hours NIHSS score as compared with initial NIHSS score, was observed in one patient. Two asymptomatic intracerebral hemorrhages were observed while no symptomatic hemorrhages were observed on serial computed tomographic scans.CONCLUSIONSThe use of intravenous eptifibatide within 24 hours in selected patients after IA thrombolysis is feasible and safe. Further studies are required to determine the benefit of early use of intravenous eptifibatide following thrombolysis.
Treatment of Extracranial Carotid Artery Pseudoaneurysms with Stent Grafts: Case Series
Authors: Gupta Rishi , Thomas Ajith J. , Masih Amit , Horowitz Michael B. 
Published: October 2009

ABSTRACTBACKGROUND AND PURPOSE Extracranial carotid artery pseudoaneurysms are a rare entity with a poorly defined natural history. Treatment has been limited to open surgical repair and limited experience with endovascular repair. We review our experience with the use of stent grafts to treat this disease entity. METHOD We retrospectively reviewed the interventional databases of two university hospitals (Michigan State University and University of Pittsburgh Medical Center) between 2004 and 2006 to identify patients with carotid pseudoaneurysms that were treated with stent grafts. A total of five patients were identified. RESULTS Of the five patients treated, four presented with acute bleeding secondary to carcinomatous invasion of the carotid artery, while one presented with thromboembolic events. Four of the five were successfully occluded with stent grafts. The one patient in whom the bleeding could not be stopped with the stent graft expired due to cardiac arrest. There were no peri‐procedural complications noted as a result of stent graft placement. CONCLUSIONS Stent grafts can be utilized to treat pseudoaneurysms safely, but may not always stop active extravasation as an isolated therapy. Long‐term data is required to determine the durability of the treatment.
Magnetic Resonance Imaging Traits in Siblings Discordant for Alzheimer Disease
Authors: Cuenco Karen T. , Green Robert C. , Zhang J. , Lunetta Kathryn , Erlich Porat M. , Cupples L. Adrienne , Farrer Lindsay A. , DeCarli Charles ,   for the MIRAGE Study Group
Published: October 2009

ABSTRACTBACKGROUND Magnetic resonance imaging (MRI) can aid clinical assessment of brain changes potentially correlated with Alzheimer disease (AD). MRI traits may improve our ability to identify genes associated with AD‐outcomes. We evaluated semi‐quantitative MRI measures as endophenotypes for genetic studies by assessing their association with AD in families from the Multi‐Institutional Research in Alzheimer Genetic Epidemiology (MIRAGE) Study. METHODS Discordant siblings from multiple ethnicities were ascertained through a single affected proband. Semi‐quantitative MRI measures were obtained for each individual. The association between continuous/ordinal MRI traits and AD were analyzed using generalized estimating equations. Medical history and Apolipoprotein E (APOE)ɛ4 status were evaluated as potential confounders. RESULTS Comparisons of 214 affected and 234 unaffected subjects from 229 sibships revealed that general cerebral atrophy, white matter hyperintensities (WMH), and mediotemporal atrophy differed significantly between groups (each at P < .0001) and varied by ethnicity. Age at MRI and duration of AD confounded all associations between AD and MRI traits. Among unaffected sibs, the presence of at least one APOEɛ4 allele and MRI infarction was associated with more WMH after adjusting for age at MRI.CONCLUSION The strong association between MRI traits and AD suggests that MRI traits may be informative endophenotypes for basic and clinical studies of AD. In particular, WMH may be a marker of vascular disease that contributes to AD pathogenesis.
MRI Shows Dorsal Lesions and Spinal Cord Atrophy in Chronic Sensory Neuronopathies
Authors: França Marcondes C. , D'Abreu Anelyssa , Zanardi Verônica A. , Faria Andréia V. , Lopes‐Cendes Iscia , Nucci Anamarli , Cendes Fernando 
Published: October 2009

ABSTRACTBACKGROUND AND PURPOSE Sensory neuronopathies (SN) represent a specific subgroup of peripheral nervous system diseases, characterized by degeneration of dorsal root ganglia (DRG) and its projections. We tried to estimate the frequency and extent of spinal cord MRI abnormalities in a group of patients with SN and correlate these with clinical and neurophysiological features. METHODS We performed spinal cord MRI scans in 16 chronic SN patients. Images were analyzed for the presence of posterior hyperintense lesions on T2WI and cord areas at C3 level were obtained using a previously validated method. A group of 14 healthy controls with similar age and gender distribution was used for comparison. ANOVA was employed for statistical analysis. RESULTS Posterior T2WI lesions were found in 13 out of 16 patients. Cord areas were significantly smaller in SN patients than controls (84.3 × 97.2 mm2, P < .05). Atrophy correlated with severity of sensory ataxia and neurophysiologic abnormalities but not with duration of disease. CONCLUSIONS These findings support volumetric spinal cord MRI as a useful tool in the assessment of chronic SN.