bluuebunny/crossref_metadata_2025_split huggingface dataset:
Insonation Method and Diagnostic Flow Signatures for Transcranial Power Motion (M‐Mode) Doppler
Authors: Alexandrov Andrei V. , Demchuk Andrew M. , Burgin W. Scott 
Published: November 2009

ABSTRACT Background and purpose. Power motion mode Doppler (PMD) simultaneously displays flow signal intensity and direction over several centimeters of intracranial space. Insonation protocol for PMD and spectral transcranial Doppler (TCD) with typical PMD flow signatures is described in serial patients with acute stroke symptoms examined via conventional windows with a PMD/ TCD unit. Results. Thirty‐five patients were studied within 12 hours after stroke onset (age 64 ±15 years; 8 received intravenous and 3 intra‐arterial thrombolysis). One patient had no temporal window, and 3 patients had suboptimal windows. In 90% of patients, PMD showed more than 1 ipsilateral temporal windows. In 63% of patients (n= 22), PMD simultaneously displayed the entire M1 (65–45 mm) and proximal M2 (45–30 mm) flows, leading to spectral TCD examination of the proximal M2 middle cerebral artery (MCA) in 28 of 35 patients (80%). All patients had sufficient foraminal (depth display = 60–110 mm) and orbital (depth display = 30–80 mm) windows. PMD displayed the entire basilar artery stem (75–100+ mm) in 69% (n= 24) of patients, and the distal basilar flow was detected in all patients by both PMD and TCD. TCD results were normal (12), proximal intracranial stenosis (5), large vessel occlusion (17), and cerebral circulatory arrest (1). Compared to spectral TCD, PMD signatures of similar diagnostic significance were low resistance (vessel identification and recanalization), high resistance (ophthalmic artery identification and distal obstruction), collateral (communicating arteries and leptomeningeal flow), reverberating (circulatory arrest), and branch embolization. Conclusions. PMD is a window‐finding tool and a guide for spectral TCD gate placement. PMD facilitates flow detection in the M2 branches and the distal basilar artery. PMD can demonstrate recanalization of the entire MCA main stem and proximal branches, increase the yield of embolus detection and procedure monitoring, and facilitate abnormal flow pattern recognition.
Reorganization of Motor Representation in a Patient with Epilepsia Partialis Continua as Shown by [O15]‐Labeled Butanol Positron Emission Tomography and Functional Magnetic Resonance Imaging
Authors: Stoeckel M. C. , Kleinschmidt A. , Ebner A. , Witte O. W. , Seitz R. J. 
Published: November 2009

ABSTRACTThe authors investigated a 38‐year‐old patient with focal cortical dysplasia in the right precentral cortex using positron emission tomography and functional magnetic resonance imaging to localize the hand and finger motor representations. The patient presented clinically with epilepsia partialis continua, supposed to originate from the perirolandic area harboring the cortical malformation. Both methods revealed an abnormal bilateral activation of motor cortex during left‐hand finger movements. The results suggest that the so‐called eloquent but nevertheless pathological dysplastic cortex accommodates motor representations.
A Reinvestigation of Maximal Signal Drop in Dynamic Susceptibility Contrast Magnetic Resonance Imaging
Authors: Liu Yi‐Jui , Chung Hsiao‐Wen , Huang Ing‐Jye , Wang Fu‐Nien , Chin Shy‐Chyi , Lee Chang‐Shin , Chen Cheng‐Yu 
Published: November 2009

ABSTRACT Background and Purpose. The purpose of this study was to reevaluate the usefulness of relative maximum signal drop (rMSD), as compared to relative cerebral blood volume (rCBV) and cerebral blood flow (rCBF), in dynamic susceptibility contrast magnetic resonance imaging (MRI). Methods. Twenty‐five patients (11 with cerebral gliomas and 14 with infarcts of middle cerebral arterial territories) were included. The rMSD values were measured from 83 regions of interest and compared with measurements from corresponding rCBV and rCBF maps. Results. In stroke patients, rMSD correlated strongly with rCBF (r= 0.96) but only fairly with rCBV (r= 0.69). The absence of an association between rMSD and rCBV was evident in regions of increased contrast bolus dispersion. In glioma patients, the correlation of rMSD with rCBF (r= 0.85) was similar to that of rMSD with rCBV (r= 0.80). The interparameter associations were well predicted by computer simulations. Conclusions. The authors conclude that rMSD is as useful as rCBF under a variety of pathophysiological conditions, whereas in conditions with normal mean transit time, such as brain tumors, rMSD provides equivalent blood volume information to rCBV. The simplicity of rMSD maps could lead to the increased use of perfusion‐weighted MRI.
Functional Magnetic Resonance Imaging in Acute Unilateral Optic Neuritis
Authors: Russ Michael O. , Cleff Ulrich , Lanfermann Heinrich , Schalnus Rainer , Enzensberger Wolfgang , Kleinschmidt Andreas 
Published: November 2009

ABSTRACTDespite good clinical criteria for diagnosing optic neuritis (ON), only a few techniques can precisely assess its impact on visual brain function. The authors studied whether functional magnetic resonance imaging (fMRI) of visual activation reliably reflects the cerebral consequences of acute unilateral ON, and how fMRI correlates with clinical function and visual evoked potentials (VEPs). Twenty ON patients, before and after steroid treatment, were compared to 20 controls. Each eye was stimulated separately with a checkerboard pattern reversing at 1, 2, 4, and 8 Hz. VEPs were recorded the same day. Initially, affected eye responses differed significantly from those of unaffected counterparts and controls in 12 patients. Post hoc classification by fMRI criteria was correct in ∼ 85%. fMRI and VEP response parameters (as well as visual acuity) correlated significantly. The higher stimulation frequencies yielded greater fMRI responses from unaffected eyes, but not from affected eyes, in controls. The fMRI responses were quantifiable in every subject, whereas in 11 ON eyes, no VEPs were obtained during the acute stage. The authors conclude that fMRI is sensitive to the cerebral response alteration during ON and might therefore contribute to evaluating the temporal evolution of the visual functional deficit during recovery or therapy.
Susceptibility Contrast and Arterial Spin Labeled Perfusion MRI in Cerebrovascular Disease
Authors: Wolf Ronald L. , Alsop David C. , McGarvey Michael L. , Maldjian Joseph A. , Wang Jiongjiong , Detre John A. 
Published: November 2009

ABSTRACT Purpose. To directly compare dynamic susceptibility contrast (DSC) and continuous arterial spin labeled (CASL) magnetic resonance (MR) perfusion techniques in patients with known cerebrovascular disease, with the goals of identifying possible pitfalls in interpretation and determining potential for a complementary role in this setting. Methods. DSC and CASL MR perfusion studies were performed and compared in 11 patients with acute and/or chronic cerebrovascular disease. Using an automated segmentation technique, Pearson correlation coefficients were generated for CASL perfusion measurements compared to DSC perfusion maps (time‐to‐peak [TTP], relative cerebral blood volume [rCBV], cerebral blood flow [rCBF], and mean transit time [MTT]) by hemisphere and vascular territory. Results. TTP maps obtained using DSC perfusion MR correlated best both subjectively and objectively with CASL perfusion MRmeasurements when all patients studied were considered. If patients with a major transit delay were excluded, DSC rCBF correlated best with CASL CBF measurements. Conclusion. There may be a complementary role for CASL and DSC perfusion MR methods in cerebrovascular disease, especially in the setting of a marked transit delay.
Transcranial Doppler Markers of Diffusion‐Perfusion Mismatch
Authors: Restrepo Lucas , Razumovsky Alexander Y. , Ziai Wendy , Barker Peter B. , Beauchamp Norman J. , Wityk Robert J. 
Published: November 2009

ABSTRACT Background and Purpose. During the evaluation of acute ischemic stroke with diffusion‐ and perfusion‐weighted magnetic resonance imaging (DWI and PWI, respectively), the presence of salvageable brain tissue is suggested by the occurrence of a perfusion‐diffusion “mismatch.” DWI and PWI, however, are not universally available and have inherent inconveniences, which justify a search for practical diagnostic alternatives. The purpose of this study is to investigate whether there are transcranial Doppler (TCD) markers of mismatch. Methods. Retrospective analysis of 22 patients with acute ischemic stroke affecting the middle cerebral artery (MCA) territory, who had a TCD performed within 24 hours of magnetic resonance imaging (MRI) with DWI and PWI. Results. MRI and TCD were performed on average 10.8 ± 9.2 hours apart. Time from symptom onset to MRI and TCD completion were 1.6 ± 1.6 and 2 ± 1.9 days, respectively. MCA and intracranial internal carotid artery (ICA) cerebral blood flow velocity (CBFV) asymmetry, together with a large ICA‐to‐MCA gradient, were associated with the presence of mismatch. The combined use of 2 TCD parameters (MCA CBFV asymmetry of ≥30% and ICA‐to‐MCA gradient ≥20 cm/sec) had a sensitivity of 75%, specificity of 80%, positive predictive value of 82%, and negative predictive value of 73% at detecting mismatch cases. Conclusions. Diffusion‐perfusion mismatch appears to be associated with interhemispheric asymmetry between MCA and ICA CBFVs, and a large CBFV gradient between the ICA and MCA on the affected side. Prospective studies are required to verify these observations and to determine whether TCD can be used to follow patients with mismatch.
Ipsilateral Hemiplegia in a Lateral Medullary Infarct– Opalski's Syndrome
Authors: Kimura Yasuyuki , Hashimoto Hiroyuki , Tagaya Masafumi , Abe Yuko , Etani Hideki 
Published: November 2009

ABSTRACTA 42‐year‐old man was admitted complaining of the sudden onset of headache, vomiting, vertigo, and gait disturbance. The authors found hemiparesis of his right limbs, right Horner's syndrome, and decreased pain and temperature sensation of his right face and left limbs. Diffusion‐weighted imaging (DWI) showed an acute small infarct located on the right side of the lateral lower medulla. This is the first report of Opalski's syndrome with lower medullary infarction detected by DWI.
Diffusion‐Weighted MRI in Creutzfeldt‐Jakob Disease: A Better Diagnostic Marker Than CSF Protein 14‐3‐3?
Authors: Mendez Oscar E. , Shang Jingzi , Jungreis Charles A. , Kaufer Daniel I. 
Published: November 2009

ABSTRACTTwo middle‐aged patients presented with rapidly progressive dementia and ataxia, nonspecific electroencephalography findings, and negative cerebrospinal fluid (CSF) protein 14‐3‐3. Both patients underwent brain magnetic resonance imaging (MRI) scans that demonstrated abnormalities on diffusion‐weighted imaging (DWI) sequences, and both were later confirmed to have Creutzfeldt‐Jakob disease (CJD) by tissue examination. Because a recent position paper from the American Academy of Neurology characterized CSF protein 14‐3‐3 as a gold standard for clinically diagnosing CJD, the authors reviewed studies of CJD in which DWI‐MRI imaging and CSF protein 14‐3‐3 studies were both performed. Among 19 reported cases of CJD with DWI‐MRI lesions, CSF protein 14‐3‐3 was negative in 6 cases and positive in 2 others. The authors' findings suggest that multifocal cortical and subcortical hyperintensities confined to gray matter regions in DWI‐MRI may be a more useful noninvasive diagnostic marker for CJD than CSF protein 14‐3‐3. These observations provide a compelling rationale for a prospective comparative study.
Reversal of Perfusion and Diffusion Abnormalities After Intravenous Thrombolysis for a Lacunar Infarction
Authors: Chalela Julio A. , Ezzeddine Mustapha , Latour Lawrence , Warach Steven 
Published: November 2009

ABSTRACTPerfusion and diffusion magnetic resonance imaging (MRI) have been used to guide therapy in patients with large vessel occlusions. In an analogous fashion, the authors used perfusion and diffusion MRI to demonstrate a perfusion deficit and a matching diffusion lesion in a patient with lacunar infarct. Following thrombolytic therapy, the authors observed a reversal of the perfusion deficit, the diffusion lesion, and clinical recovery. This case suggests that perfusion and diffusion MRI may be informative in patients with lacunar infarction who are candidates for thrombolysis.
Variability and Validity of a Simple Visual Rating Scale in Grading White Matter Changes on Magnetic Resonance Imaging
Authors: Fan Yu Hua , Lam Wynnie W. M. , Mok Vincent C. T. , Huang Ru Xun , Wong Ka Sing 
Published: November 2009

ABSTRACT Background and Purpose. A new simple visual rating scale can be used in magnetic resonance imaging (MRI) to grade the severity of white matter changes (WMC). The authors sought to study the interobserver variability and the validity of this visual rating scale against a computer‐aided quantitative method in measuring WMC. Methods. The authors examined 220 magnetic resonance images from stroke‐free patients with traditional risk factors for atherosclerosis and middle cerebral artery stenosis who were participants in a clinical trial requiring MRI examination. The severity of WMC was graded from 0 (no WMC) to 3 (severe WMC). For the quantitative assessment of WMC, the volume of WMC were measured with a computer‐aided, automated segmentation method. The interobserver variability was also determined. Results. The mean volumes were significantly different among the different groups, which were scored 1, 2, and 3 (1324.59, 6475.48, and 25,440.05 mm3, respectively; 1‐way analysis of variance, P < .001). Interobserver variability for grading WMC was good in different locations of the brain. Excellent results were found in the frontal lobe (κ=0.829) and the parietal‐occipital lobe (κ=0.646), whereas poor results were found in the basal ganglia (κ=0.391). There was perfect agreement between the 2 observers in 89.1% for the frontallobe and 77.0% for the parietal‐occipital lobe. Conclusions. The results suggest that this simple visual rating scale is a valid and reliable method for grading WMC in the lobar region but not in the basal ganglion.
Subcortical Hypointensity in Partial Status Epilepticus Associated with Nonketotic Hyperglycemia
Authors: Seo Dae Won , Na Dong Gyu , Na Duk L. , Moon So Young , Hong Seung Bong 
Published: November 2009

ABSTRACTTransient gray and white matter magnetic resonance signal changes have frequently been reported because of underlying epileptic activity. However, transient subcortical hypointensity on T2 and fluid‐attenuated inversion recovery images in the setting of status epilepticus (SE) has rarely been reported. The authors note 3 of 6 retrospective cases with partial SE associated with nonketotic hyperglycemia showing transient subcortical T2 hypointensity near the epileptic focus. These changes may be due to the accumulation of free radicals and iron deposition related to a hyperglycemia‐induced hypoxic‐ischemic state.
Bilateral Internal Carotid Artery Dissection Mimicking Inflammatory Demyelinating Disease
Authors: Lie C. , Schwenk S. , Szabo K. , Lanczik O. , Hennerici M. G. , Gass A. 
Published: November 2009

ABSTRACT Background and Purpose. Internal carotid artery (ICA) dissection (ICAD) may be extremely difficult to diagnose only on the basis of historical information and clinical signs, and even standard brain imaging (computed tomography [CT], T2‐weighted magnetic resonance imaging [MRI]) may not be sufficient to delineate the underlying pathology clearly, as shown in this case. Methods. The clinical presentation and parenchymal lesion pattern on CT were suggestive of inflammatory demyelinating disease, and additional multiparametric MRI was per‐formed. Results. Diffusion‐weighted MRI, magnetic resonance angiography, and perfusion‐weighted MRI revealed acute ischemic lesions, bilateral ICA obstruction, and bilateral hypoperfusion in the middle cerebral artery territories. Bilateral ICAD was confirmed by Doppler and duplex ultrasound, and anticoagulation therapy was initiated. A follow‐up examination showed recanalization of the obstructed ICAs and the normalization of cerebral perfusion. Conclusion. This case illustrates the importance of demonstrating the pathology and the value of multiparametric MRI techniques for the diagnosis and monitoring of ICAD and its hemodynamic consequences.
“Congenital” Horner's Syndrome and Carotid Dissection
Authors: Robertson William C. , Pettigrew L. Creed 
Published: November 2009

ABSTRACTThe authors describe a child presenting with Horner's syndrome after the repeated application of birthing forceps to the head and neck during vaginal delivery. Magnetic resonance imaging and angiography confirmed that the proximal right internal carotid artery (ICA) showed injury caused by dissection. Carotid duplex and transcranial ultrasonography provided supporting evidence of distal right ICA occlusion with the development of intracranial collaterals. The authors interpret these findings to indicate that the child suffered a traumatic dissection of the distal right ICA to mimic “congenital” Horner's syndrome (CHS). In a review of English medical literature published since 1972, the authors found 70 cases of CHS, none of which was attributed to carotid dissection. This case demonstrates that carotid dissection is an underreported cause of CHS.
Voxel‐Based Mapping of Cortical Ischemic Damage Using Tc 99M L, L‐Ethyl Cysteinate Dimer Spect in Acute Stroke
Authors: Mahagne Marie‐Hélène , David Olivier , Darcourt Jacques , Migneco Octave , Dunac Antoine , Chatel Marcel , Baron Jean‐Claude 
Published: November 2009

ABSTRACT Background and Purpose. When performed soon after stroke onset, single‐photon emission computed tomography (SPECT) with hexamethylpropylenamine oxime or Tc 99m L, L‐ethyl cysteinate dimer (ECD) has significant added predictive value compared to neurological scores. With ECD SPECT, the degree of tracer uptake reduction predicts neurological recovery, and using a 40% threshold to characterize irreversibly damaged tissue (IDT), significant correlations have been observed. How‐ ever, correlations between this uptake threshold and tissue out‐ comes have not been assessed. The purpose of this study was to validate the 40% ECD uptake threshold for the probabilistic mapping of IDT using an automatic, voxel‐based approach. Methods. In 10 acute stroke patients, the authors first com‐ pared early ECD SPECT and late coregistered magnetic reso‐ nance imaging (MRI) data and assessed for IDT and “tissue at risk” (ie, tissue with ECD uptake below and above 40%) the per‐ centage of voxels ultimately infarcted and noninfarcted on late brain MRI. They then assessed the correlations between the vol‐ umes of brain tissue compartments and subsequent neurologi‐ cal recovery. Finally, to assess whether visual SPECT analysis is reliable compared to the more complexvoxel‐based approach, the authors compared the predictive value of the 2 methods for neurological recovery. Results. The majority of IDT voxels (aver‐ age = 84%), defined by ECD uptake < 40%, evolved toward infarction, and 51.8% to 100% of at‐risk voxels (average = 89%) escaped infarction. The extent of IDT correlated significantly with neurological recovery (P= .0009). There was good agree‐ ment between visual and voxel‐based analyses (P= .0004). Conclusion. The results support the validity of the ECD uptake thresholds chosen, suggesting that ECD uptake can reflect neuronal viability and that ECD SPECT can be useful for the early detection of potentially salvageable tissue and irreversible damage. These preliminary results encourage the use of this method in a clinical setting for fast decision making in choosing acute therapy.
Brain Tissue Water Uptake after Middle Cerebral Artery Occlusion Assessed with CT
Authors: Dzialowski Imanuel , Weber Johannes , Doerfler Arnd , Forsting Michael , Von Kummer Rüdiger 
Published: November 2009

ABSTRACT Background and Purpose. To study whether computed tomography (CT) can measure the water content of early ischemic edema. Methods. The authors obtained cranial CT in 5 groups of rats subjected to 1 hour (n = 8),2 hours (n = 11),3 hours (n = 13),4 hours (n = 13), or 6 hours (n = 14) of right middle cerebral artery (MCA) occlusion. Immediately after CT, the authors removed the rats’ brains and determined tissue water content by the dry‐wet weight method. They correlated brain x‐ray attenuation with brain tissue water content. Results. Mean brain tissue water content remained constant in the nonischemic left hemispheres at 77.9%± 0.6% and increased up to 79.3%± 1.0% in the right hemispheres after 6 hours of permanent right MCA occlusion. X‐ray attenuation remained constant in the left hemispheres at 75.6 ± 2.2 Hounsfield units (HU) and decreased to 71.7 ± 3.4 HU in the right hemispheres after 6 hours of right MCA occlusion. The decrease in x‐ray attenuation correlated significantly with the increase in ischemic brain tissue water content (y= 217.3 – 1.8 ×x; r= .55, P < .0001). That means that a 1% increase in hemispheric tissue water content causes a decrease in x‐ray attenuation of 1.8 HU. Conclusions. After MCA occlusion, immediate brain tissue net water uptake is associated with a decrease in x‐ray attenuation. CT can monitor ischemic edema in an acute stroke.
Treatment of Marburg Variant Multiple Sclerosis with Mitoxantrone
Authors: Jeffery Douglas R. , Lefkowitz David S. , Crittenden Jeffrey P. 
Published: November 2009

ABSTRACTMarburg variant multiple sclerosis (MS) is a severe, sometimes monophasic, form of MS leading to advanced disability or death within a period of weeks to months. No consistently successful treatment for Marburg variant MS has been described. The case reported here is that of a 34‐year‐old woman with Marburg variant MS whose magnetic resonance imaging scan showed extensive brainstem, periventricular white matter, subcortical, and cortical involvement, giving the appearance of an “MS cerebritis.” The patient had no response to treatment with methylprednisolone but improved and recovered after treatment with mitoxantrone (MITX). Because MITX has potent anti‐inflammatory effects and demonstrated efficacy in worsening MS, it may be an appropriate agent for the treatment of Marburg variant MS.
Reliability of Semiquantitative Ultrasonic Perfusion Imaging of the Brain
Authors: Eyding Jens , Wilkening Wilko , Reckhardt Markus , Meves Saskia , Postert Thomas 
Published: November 2009

ABSTRACTBackground and Purpose. Contrast burst depletion imaging (CODIM) visualizes cerebral perfusion by destruction of microbubbles and observation of image intensity course. Because of its complexity, artifacts occur. Criteria of reliability to improve diagnostic significance were created and validated. Methods and Results. Eighteeen healthy volunteers were examined with 2 echo contrast agents (ECAs) and 3 frame rates in 3 regions of interest (ROIs). Perfusion coefficient (PC), T min (time todecrease intensity to 10% of its max), and relative error (RE) (deviation of measured data from fitted model) were determined. PC differed significantly neither between CA nor between frame rates (overall mean = 1.60 ± 0.21 · 10 – 2s –1). Tmindiffered significantly between frame rate groups (P< .001, 33.4 ± 11.2 s/0.5 Hz; 3.6 ± 2.5 s/5 Hz) since it is related to destruction of microbubbles that occurs with each frame and to the perfusion rate. RE was higher in the Optison group and tended to decrease in ROIs closer to the probe. Conclusions. PC was independent of frame rate and ECA. T min was shorter with higherframe rates. Due to a very rapid decay at 5 Hz, the ideal frame rate should be about 1 Hz, that is, because the number of frames acquired within T min and therefore signal‐to‐noise ratio ishigher at 1 Hz. Since the algorithm is complex (high RE) and more artifacts should occur in patients (insufficient bone window, etc), a triggering of the insonations by, for example, heart rate could decrease artifacts and increase diagnostic power of CODIM.