bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Prevalence of Asymptomatic Intracranial Large‐Vessel Occlusive Disease: The Role of Diabetes
Authors: Elmore Erin M. , Mosquera Aurelio , Weinberger Jesse 
Published: November 2009

ABSTRACT Objective. To investigate the prevalence of asymptomatic intracranial stenosis using transcranial Doppler ultrasonography in patients with evidence of asymptomatic carotid stenosis. Background. Symptomatic atherosclerotic intracranial largeartery stenosis accounts for approximately 10% of ischemic strokes annually. It is unknown whether a significant risk for stroke is associated with asymptomatic intracranial stenosis, especially in patients with known asymptomatic carotid disease. Design and Methods. Transcutaneous real‐time B‐mode Doppler ultrasonography was performed on 510 patients referred for the evaluation of asymptomatic carotid bruits. A peak systolic flow velocity > 1.40 m/s indicated carotid stenosis. Transcranial Doppler ultrasound was performed to identify intracranial large‐artery disease. The peak systolic flow velocity indicating stenosis was > 120 cm/s for anterior circulation and > 100 cm/s for posterior circulation. Demographic and cerebrovascular risk factor information was recorded at the time of examination. Chi‐square analysis with Pearson correction was performed to examine the significance of the findings. Results. Five hundred ten patients (252 male, 258 female) aged 71.4±10.45 years were studied. The laboratory's accuracy was previously established as 93% for each technique for laboratory certification. Two hundred patients (39.2%) were found to have extracranial carotid stenosis, and 66 (12.9%) were found to have intracranial stenosis. Thirty‐seven patients (56%, P < .01) were found to have concurrent stenosis. In patients with intracranial stenosis, 19 (28.8%, P < .03) had diabetes, and 26 (39.4%, p < .03) had coronary disease. There was no corresponding correlation with extracranial carotid disease and diabetes or coronary artery disease. Conclusions. The prevalence of patients with asymptomatic intracranial stenosis with concurrent carotid stenosis was greater than expected. Coexisting diabetes and coronary disease were significant risk factors in this population. Doppler ultrasonography may be a useful technique in delineating asymptomatic intracranial stenosis in those patients with existing carotid stenosis. Further studies are needed to clarify the risk of this population for stroke from asymptomatic intracranial stenosis and to determine optimal therapy.
Brain CT and MRI Findings in 100 Consecutive Patients with Intracranial Tuberculoma
Authors: Wasay Mohammad , Kheleani Bhojo A. , Moolani Mahesh K. , Zaheer Jazia , Pui Margaret , Hasan Sheema , Muzaffar Suhail , Bakshi Rohit , Sarawari Arif R. 
Published: November 2009

ABSTRACT Objective. The characteristics of intracranial tuberculoma on computed tomography (CT) and magnetic resonance imaging (MRI) are not well known. The authors reviewed the features of tuberculoma on CT scans and MRI. The authors also correlated the MRI characteristics on various pulse sequences with neuropathological findings. Methods. The charts of patients with intracranial tuberculoma were consecutively reviewed during the period from 1988 to 1999. The diagnosis of tuberculoma was based on pathology (n = 19), clinical or neuroimaging response to tuberculous chemotherapy (n = 57), or evidence of systemic tuberculosis (n=24). Neuropathological specimens of tuberculoma were graded for the amount of fibrosis, gliosis, necrosis, and cell types (lymphocytes, macrophages, plasma cells). Results. One hundred patients (43 men) were identified. The age range was 1 to 75 years (mean = 30 y). The number of lesions ranged from 1 to > 100 (mean = 4.5 lesions/patient). Thirty‐one patients had solitary lesions, whereas 69 had multiple lesions. Thirty‐seven patients had hydrocephalus. After contrast administration, >450 lesions were seen on CT and MRI images in all 100 scans. The diameter of these enhancing lesions ranged from 1 mm to 5 cm. Lesions > 1 cm showed varied enhancement, including irregular shapes, ringlike shapes, open rings, and lobular patterns. Targetlike lesions were seen in only 2 patients. Other features included cortical and subcortical infarcts (12 patients), calcification (10% of lesions), edema (33 patients), meningeal enhancement (12 patients), mass effect, and/or midline shift (18 patients). A hypointense core with a hyperintense rim was the most common signal characteristic on T2‐weighted MRI. The central hypointensity on T2‐weighted and fluid‐attenuated inversion recovery (FLAIR) images reflected extensive necrosis and hypercellularity. Conclusion. Multiple tuberculomas and infratentorial locations were more common in the authors'patient population than in previous reports. The MRI signal characteristics of intracranial tuberculoma are extremely diverse. An isointense or hypointense core with a hyperintense rim on T2‐weighted and FLAIR images is the most common presentation. Core hypointensity of lesions on these images is related to necrosis and the large number of cells.
Symmetry of Cerebral Hemodynamic Indices Derived from Bilateral Transcranial Doppler
Authors: Schmidt Eric A. , Piechnik Stefan K. , Smielewski Piotr , Raabe Andreas , Matta Basil F. , Czosnyka Marek 
Published: November 2009

ABSTRACT Objective. The authors evaluated with bilateral transcranial Doppler (TCD) ultrasonography the norm of interhemispheric difference for several cerebrovascular hemodynamic parameters. Methods. Forty‐four volunteers (33 male, 11 female; average age = 21 years; range, 20–23 years) were studied. The authors recorded bilateral systolic, diastolic, and mean flow velocity (FV) and noninvasive systolic, diastolic, and mean arterial blood pressure. Calculated indices included Gosling's pulsatility index (GPI), an index of autoregulation (Mx), critical closing pressure (CCP), and a noninvasive estimator of cerebral perfusion pressure (nCPP). All indices were averaged per side and patient. For each parameter, the left‐right correlation coefficient (r2) and the 95% confidence limit of the left‐right differences were calculated. Results. All TCD‐derived indices displayed significant correlations between the left and right sides: r2=0.49 for mean FV (FVm), r2=0.66 for GPI, r2=0.79 for Mx, r2=0.93 for CCP, and r2=0.94 for nCPP. The 95% confidence intervals for the left‐right differences were 20 cm/s for FVm, 0.16 for GPI, 0.18 for Mx, 13 mm Hg for CCP, and 4.6 mm Hg for nCPP. Conclusions. This study gives the reference values for the assessment of left‐right symmetry of cerebral hemodynamics using various TCD‐derived indices. These reference values should be useful for clinical studies assessing the left‐right asymmetry of cerebral hemodynamics on a daily basis.
Magnetic Resonance Imaging of Meningoradiculomyelitis in Early Disseminated Lyme Disease
Authors: Tullman Mark J. , Delman Bradley N. , Lublin Fred D. , Weinberger Jesse 
Published: November 2009

ABSTRACTLyme disease, a multisystem illness caused by the spirochete Borrelia burgdorferi, is the most common vector‐borne disease in the United States. There are 3 clinical stages of Lyme disease: early localized, early disseminated, and late persistent disease. Neuroborreliosis, infection of the nervous system by B. burgdorferi, may occur during early disseminated or late persistent disease. Spinal cord involvement in early disseminated disease is extremely rare. In patients with early disseminated neuroborreliosis, treatment with antibiotics often leads to rapid recovery and may prevent further complications of Lyme disease. The authors present the clinical and radiographic findings, both before and after treatment, in a patient with meningoradiculomyelitis due to early disseminated Lyme disease.
Pituitary Apoplexy in the Setting of Coronary Angiography
Authors: Skljarevski Vladimir , Khoshyomn Sami , Fries Timothy J. 
Published: November 2009

ABSTRACTPituitary apoplexy (PA) is a rare but potentially life‐threatening event. Typically, it results from hemorrhage into a pituitary adenoma, although cases affecting the intact gland have been reported. PA may occur spontaneously or in a setting of certain diagnostic and therapeutic procedures. The association of PA and contrast administration in the setting of neuroimaging have been postulated. The authors report a case of PA following coronary angiography. To the best of the authors'knowledge, this scenario has not been previously reported. A 66‐year‐old woman with a congenital septal defect underwent coronary angiography that was technically uncomplicated. After the procedure, the patient experienced retro‐orbital pain and developed ophthalmoplegia. Magnetic resonance imaging (MRI) showed a hemorrhagic sellar mass extending into the cavernous sinus. A 3‐month follow‐up MRI revealed cystic changes. The patient expired 4 months later because of cardiorespiratory failure. PA in the absence of adenoma was confirmed on autopsy. The authors hypothesize that apoplexy here was related to the administration of Omnipaque in combination with the anticoagulation effect of heparin.
Roles for Imaging in Understanding the Pathophysiology, Clinical Evaluation, and Management of Patients with Mitochondrial Disease
Authors: Parry A. , Matthews P. M. 
Published: November 2009

ABSTRACTPrimary mitochondrial disorders remain uncommon, but they enter into the differential diagnosis for a broad range of syndromes. Functional and structural imaging methods offer important clinical tools for patient assessment when these diseases are suspected. Although the findings are not specific, in the appropriate clinical context, these tests can guide the use of more specific or invasive investigations. They have provided considerable information concerning the underlying pathophysiology of this heterogeneous range of disorders. Monitoring these changes potentially facilitates the identification of new therapies and their individualization.
Thalamic Involvement in Multiple Sclerosis: A Diffusion‐Weighted Magnetic Resonance Imaging Study
Authors: Fabiano Andrew J. , Sharma Jitendra , Weinstock‐Guttman Bianca , Munschauer Frederick E. , Benedict Ralph H. B. , Zivadinov Robert , Bakshi Rohit 
Published: November 2009

ABSTRACT Background and Purpose. Injury to deep gray matter structures in multiple sclerosis (MS) has been suggested by recent neuroimaging and neuropathology studies. Diffusion‐weighted magnetic resonance imaging (MRI) can assess tissue damage with greater sensitivity than conventional MRI. The authors'objective was to assess thalamic gray matter damage by diffusion‐weighted imaging in MS patients. Methods. This was a retrospective study performed at a tertiary care, university‐affiliated comprehensive MS center of 82 MS patients and 43 controls. The main outcome measures were thalamic apparent diffusion coefficients (ADCs), whole‐brain atrophy (brain parenchymal fraction), fluid‐attenuated inversion recovery (FLAIR) hyperintense lesion volume, and clinical course. Results. ADCs in the left thalamus were higher in MS patients (0.741 ± 0.044 × 10−3 mm2/s) than controls (0.723 ± 0.036 × 10−3 mm2/s) (P= .027) and higher in secondary progressive MS patients (0.761 ± 0.044 × 10−3 mm2/s) than relapsing‐remitting MS patients (0.735 ± 0.032 × 10−3 mm2/s) (P= .029). ADCs in the right thalamus were higher in secondary progressive MS patients (0.784 ± 0.069 × 10−3 mm2/s) than controls (0.757 ± 0.038 × 10−3 mm2/s) (P= .033). In the MS group, left thalamus ADCs correlated negatively with brain parenchymal fraction (r= ‐0.30, P= .008), total left hemispheric FLAIR lesion volume correlated with ADCs in the left (r= 0.35, P= .001) and right (r= 0.39, P < .001) thalami, and total right hemispheric FLAIR lesion volume correlated with ADCs in the left (r= 0.31, P= .006) and right thalami (r= 0.22, P= .048). Conclusion. MS patients have increased water diffusion in the thalamus that is partly associated with clinical course, lesion load, and whole‐brain atrophy. Both indirect and direct mechanisms of gray matter injury may play a role in the pathophysiology of MS.
Contrast M‐Mode Power Doppler Ultrasound in the Detection of Right‐to‐Left Shunts: Utility of Submandibular Internal Carotid Artery Recording
Authors: Topçuoglu M. A. , Palacios I. F. , Buonanno F. S. 
Published: November 2009

ABSTRACTCardiac right‐to‐left shunts (RLSs) can be detected by echo‐cardiography and transcranial Doppler ultrasound (TCD). In patients without adequate transtemporal bone windows, results may be obtained by insonating extracranial arteries; however, the sensitivity and practicality of this approach is unknown. In 34 patients evaluated with echocardiography for RLSs, 73 studies were performed with unilateral, simultaneous contrast TCD (cTCD) of the middle cerebral artery (MCA) and anterior cerebral artery (ACA) and submandibular power M‐mode Doppler (PMD)ultrasound of the extracranial internal carotid artery (ecICA). The number of microbubble (MB) signals and their times of first appearance were determined. RLS volume was graded on 6 levels (I = trace, II = small, III = medium, IVa = large, IVb = shower, IVc = curtain) and compared between MCA and ecICA recordings. In 2 of 24 cTCD studies in 15 patients without evidence of RLSs on single‐gated MCA monitoring, low‐volume RLSs (grades I and II) were detected via ecICA insonation; in both, MB signatures were tracked in the ecICA, passing into the ipsilateral ACA. In 40 of 49 studies (26 patients) in which RLSs were demonstrated with single‐gated MCA monitoring, more MBs were detected in the ecICA than the MCA, with either single‐gated or M‐mode images, with increases of 76.9% and 66.1%, respectively (P= .027). Compared to single‐gated studies, M‐mode technology detected nonsignificant increases in MB number in both the MCA and the ecICA (by 20.2% and 14.0%, respectively). Contrast PMD with cervical ICA recording is at least as sensitive and specific as the traditional MCA method in detecting RLSs; furthermore, this method seems to be more sensitive for low‐volume RLSs (grades I‐III) because of air MB decay (9.2%) and entry into the ipsilateral ACA (34.2%). This is in concordance with the increase of detected RLS grades observed in 32.7% of patients with echocardiography‐documented RLSs. The authors therefore suggest the incorporation of ecICA PMD not only in patients with poor ultrasonic bone windows but also in every patient being evaluated for suspected RLSs.
Diffusion‐Weighted Echo‐Planar MRI of the Brain with Calculated ADCs: A Useful Tool in the Differential Diagnosis of Tumor Necrosis from Abscess?
Authors: Dorenbeck U. , Butz B. , Schlaier J. , Bretschneider T. , Schuierer G. , Feuerbach S. 
Published: November 2009

ABSTRACT Background and Purpose. It was the aim of this study to evaluate whether brain abscesses could be distinguished reliably from necrotic brain tumors using diffusion‐weighted imaging (DWI) with calculated apparent diffusion coefficients (ADCs). Methods. The authors studied 27 lesions in 26 patients (21 tumors and metastases, 5 pyogenic brain abscesses, and 1 cerebral toxoplasmosis). DWI was obtained with a single‐shot echo‐planar imaging spin‐echo sequence. ADCs were calculated for all images. Results. ADCs (× 10−3 mm2/s) measured in the necrotic parts of the tumors ranged from 2.94 (glioblastoma) to 1.51 (astrocytoma III). In the inflammatory lesions, ADCs ranged between 0.91 and 3.07 (cerebral toxoplasmosis and pyogenic abscess). The contrast‐enhanced parts of the lesions showed ADC values from 0.77 (pyogenic abscess) up to 1.68 (glioblastoma). Conclusions. DWI with calculated ADC values does not allow the reliable differentiation of enhanced central necrotic intracranial lesions.
Volume Flow in the Common Carotid Artery does not Decrease Postprandially
Authors: Eicke Bernhard Martin , Seidel Elisabeth , Krummenauer Frank 
Published: November 2009

ABSTRACT Background and Purpose. A commonplace explanation for postprandial fatigue is the assumption of the redistribution of perfusion from the cerebral to the mesenterial territory. However, this assumption has never been scientifically proven. Methods. Because approximately 70% of the blood flow in the common carotid artery (CCA) is directed to the internal carotid artery, this vessel can be seen as a major brain‐supplying artery. Flow volume in the CCA can be measured by color M‐mode duplex sonography. The authors investigated the flow volume rate in 20 healthy volunteers before and after the intake of a high‐energy meal. Heart rate, blood pressure, and expiratory CO2 were also measured at both times. Results. There was a significant (P= .001) increase in right, left, and net CCA flow volume postprandially (right: from 362.0 [interquartile range 315.5–410.5] to 401.5 [322.1–486.4] mL/min; left: from 384.5 [345.5–439.0] to 414.5 [357.9–527.7] mL/min; net: from 756.0 [683.0–822.5] to 832.4 [713.7–967.26] mL/min). This increase was paralleled by a statistically significant increase in heart rate from 66 (58–70) to 76 (63–84) bpm, but without substantial correlation (r= 0.28) with the volume flow changes. There was no correlation with any other tested parameter. Conclusions. The authors conclude that the assumption of global brain hypoperfusion in the postprandial state cannot serve as an explanation for postprandial fatigue.
Endovascular Treatment of a Left Carotid Artery “Bowtie” Pseudoaneurysm with a Covered Wallgraft Stent
Authors: Koenigsberg Robert A. , Urrutia Victor , McCormick Daniel , Alani Firas , Ryu David , Nair Bronwyn , Thomas Carole 
Published: November 2009

ABSTRACTThe authors present an unusual case of a young male patient with a large left common carotid artery pseudoaneurysm in a shape similar to that of a bowtie treated with a covered Wallgraft. The Wallgraft is a covered stent originally designed to be used in the treatment of tracheobronchial fistula and peripheral arterial applications. The favorable out‐come of this case illustrates its endovascular application in nonsurgical traumatic injuries of the carotid artery.
Giant Axonal Neuropathy: MRS Findings
Authors: Alkan Alpay , Kutlu Ramazan , Sigirci Ahmet , Baysal Tamer , Altinok Tayfun , Yakinci Cengiz 
Published: November 2009

ABSTRACTGiant axonal neuropathy (GAN) is a rare genetic disease of childhood involving the central and peripheral nervous systems. Axonal loss with several giant axons filled with neurofilaments is the main histopathological feature of peripheral nerve biopsies in this disease. Routine neuroimaging studies reveal diffuse hyperintensities in cerebral and cerebellar white matter. In this case report, the authors present the brain magnetic resonance spectroscopic features (normal N‐acetylaspartate/creatine and increased choline/creatine and myoinositol/creatine ratios), which might indicate the absence of neuroaxonal loss and the presence of significant demyelination and glial proliferation in white matter, of an 11‐year‐old boy diagnosed with GAN.
Asymmetric Neuroimaging in Creutzfeldt‐Jakob Disease: A Ruse
Authors: Bavis James , Reynolds Patrick , Tegeler Charles , Clark Paige 
Published: November 2009

ABSTRACTCreutzfeldt‐Jakob disease (CJD) causes diffuse neurological symptoms, but asymmetric lesions have been found on conventional magnetic resonance imaging (MRI) and diffusion‐weighted imaging (DWI).Less often, positron emission tomography (PET) scanning can also reveal asymmetric lesions in patients with CJD. Such imaging may mislead clinicians. The authors present a case of a woman with CJD who was diagnosed as having suffered a stroke because she had asymmetric T2‐weighted imaging (T2WI) MRI abnormalities that were interpreted as a stroke. It was noted that the patient had clinical features consistent with CJD, including rapidly progressive dementia, myoclonus, cerebellar dysfunction, and pyramidal and extrapyramidal signs. This diagnosis was supported by periodic epileptiform discharges on the electroencephalogram (EEG) and by elevated 14‐3‐3 protein in the cerebrospinal fluid. MRI T2WI and DWI showed dramatically asymmetric abnormalities involving the left cortex. A PET study found decreased metabolism in the left cerebral and right cerebellar hemispheres. The patient's clinical, EEG, and laboratory data were all consistent with CJD, not other diseases, but the MRI and PET had atypical, asymmetric findings. This case demonstrates that CJD should be considered in the differential diagnosis of patients with rapidly progressive neurological decline, even if they have asymmetric imaging findings.
Characteristics and Predictors of Aortic Plaques in Patients with Transient Ischemic Attacks and Strokes
Authors: Yahia Abutaher M. , Kirmani Jawad F. , Xavier Andrew R. , Shaukat Aasma , Qureshi Adnan I. 
Published: November 2009

ABSTRACT Objective. To identify the prevalence and characteristics of aortic atherosclerotic plaque disease and its association with cerebrovascular risk factors in patients with cerebral ischemic events. Background. Aortic atheroma is associated with ischemic stroke. Its characteristics, including morphology and distribution among different stroke subtypes, are not well described. Method. From July 2000 to August 2001, all patients evaluated by transesophageal echocardiography (TEE) with diagnoses of transient ischemic attacks (TIAs) and strokes were prospectively studied. Demographics, including age, gender, ethnicity, cerebrovascular risk factors, and stroke subtypes, were collected. Results. Thoracic aortic atheromas (TAAs) were present in 141 of 237 patients (59%) (mean age = 59 ± 14, 119 [50%] male). Mild plaque (<2mm) was present in 13 of 237 (5%), moderate plaque (2–4 mm) in 49 (21%), severe plaque (≥4 mm) in 79 (33%), and complex plaque in 64 (27%). Patients’ ages (odds ratio [OR] = 1.05, confidence interval [CI] 1.03–1.08, P < .001), coronary artery disease (OR = 2.2, CI 1.02–4.8, P < .042), and patent foramen ovale (PFO) (OR = 0.39, CI 0.22–0.70, P < .002) were associated with the severity and complexity of aortic plaque. In multivariate analysis, age (OR = 1.06, CI 1.03–1.08, P < .001) and the presence of PFO (OR = 0.35, CI 0.18–0.65, P < .001) continued to be significant to the severity and complexity of aortic atheroma. Gender, history of stroke, hypertension, diabetes mellitus, hyperlipidemia, and history of smoking were not associated with TAA. Conclusion. One third of TAA plaques are severe and complex in nature and more frequently present in the descending aorta and the arch of the aorta than in the ascending aorta. TEE should be considered for the early detection and treatment of TAA in patients without identified causes of stroke.
Multiple Cerebral Microbleeds: Mri Marker of a Diffuse Hemorrhage–Prone State
Authors: Chalela Julio A. , Kang Dong‐Wha , Warach Steven 
Published: November 2009

ABSTRACT Background. Recent reports have indicated that cerebral microbleeds (CMBs) detected on gradient‐echo (GRE) magnetic resonance imaging may be a risk factor for therapy‐related intracranial hemorrhages (ICHs). Case Description. The authors describe 3 patients with multiple CMBs in whom ICHs occurred either after tissue plasminogen activator administration or after the initiation of antiplatelet therapy. Hemorrhages occurred in brain areas with normal appearances on GRE imaging and remote from the CMBs. Conclusion. Multiple CMBs may signal a diffuse hemorrhage–prone vasculopathy.