bluuebunny/crossref_metadata_2025_split huggingface dataset:
Frequent Hemorrhagic Lesions in Cerebral Toxoplasmosis in AIDS Patients
Authors: Bhagavati Satyakam , Choi Jai 
Published: October 2009

ABSTRACT Cerebral toxoplasmosis is a frequent complication in immunosuppressed patients such as AIDS (acquired immunodeficiency syndrome). Frequently, lesions are located deep in the brain which are inaccessible for biopsy making rapid diagnosis dependent on accurate interpretation of neuroimaging findings. The commonest cranial CT findings reported in toxoplasmosis are ring enhancing hypodense lesions in basal ganglia or cortical gray matter. Hemorrhage has only rarely been described and is usually seen following antitoxoplasma treatment. We reviewed the records of 11 AIDS patients with cerebral toxoplasmosis and found multiple hemorrhagic cerebral, cerebellar, or brain stem lesions in 7 of 11 patients. Six patients had hemorrhage at the time of initial clinical presentation and one developed hemorrhage following 2 weeks of antitoxoplasma treatment. We conclude that hemorrhagic lesions are frequently found on cranial MRI scans in cerebral toxoplasmosis. AIDS patients presenting with hemorrhagic cerebral lesions should be considered for a trial of presumptive antitoxoplasma treatment.
Unilateral versus Bilateral Middle Cerebral Artery Detection of Right‐to‐Left Shunt by Power M‐Mode Transcranial Doppler
Authors: Jesurum Jill T. , Fuller Cindy J. , Moehring Mark A. , Renz Joshua , Harley Meryl , Spencer Merrill P. 
Published: October 2009

ABSTRACTBACKGROUND AND PURPOSE Comparison was performed between unilateral and bilateral power M‐mode transcranial Doppler to detect right‐to‐left circulatory shunt (RLS). METHODS Recorded Doppler data from 87 patients with confirmed RLS referred for transcatheter closure of patent foramen ovale were reanalyzed for embolic tracks (ET) counted from left and right temporal bone windows during bubble study. Unilateral counts were obtained by multiplying each side by 2; bilateral counts were obtained by summing left and right ET. Both unilateral and bilateral ET were converted to a 6‐point logarithmic grade. Sex and age group subanalyses were performed. RESULTS At rest, significantly more ET were detected with bilateral versus unilateral detection (P= .01), but not following Valsalva (P= .13). Unilateral and bilateral detection were equally able to detect large RLS (grades IV or V) following Valsalva (P= 1.00). For the group aged ≥55 years, the right‐hand side yielded greater ET than the left‐hand side (mean difference 9%± 37; 95% confidence interval −3 to 21%) at rest (P= .01), but not following Valsalva (mean difference 1%± 25; 95% confidence interval −7 to 9%, P= .10). CONCLUSIONS Unilateral detection of ET by power M‐mode transcranial Doppler is equivalent to bilateral detection to assess RLS.
Variant of Subclavian Steal in the Setting of Ipsilateral Common Carotid Artery Occlusion: Case Report
Authors: Tummala Ramachandra P. , Ecker Robert D. , Levy Elad I. 
Published: October 2009

ABSTRACT Subclavian steal is a well‐described angiographic finding and clinical syndrome that rarely results in vertebrobasilar ischemic symptoms. In classic subclavian steal, left subclavian artery (SA) stenosis occurs proximal to the left vertebral artery (VA) origin. We report a symptomatic variant of this syndrome that occurred in the setting of left common carotid artery occlusion and anomalous origin of the left VA directly from the aortic arch. The steal and symptoms resolved after stenting of the left SA stenosis.
Ultrasound Velocity Criteria for Vertebral Origin Stenosis
Authors: Koch Sebastian , Romano Jose G. , Park Hannah , Amir Murtaza , Forteza Alejandro M. 
Published: October 2009

ABSTRACTBACKGROUND Despite remaining an important cause of posterior circulation stroke, the non‐invasive diagnosis of vertebral artery origin (VAo) stenosis is problematic. We here examine peak systolic velocity (PSV) criteria for the diagnosis of VAo stenosis and assess if the PSV ratio at the origin to the distal segments improves diagnostic accuracy. METHODS We performed a retrospective analysis of patients studied by catheter cerebral angiography and extracranial Duplex ultrasonography. The angiographic degree of stenosis, PSV at the VAo, proximal vertebral artery (VA1), and intra‐foraminal (VA2) segment were recorded. We calculated the VAo/VA1 and VAo/VA2 PSV ratio. A receiver operator curve was obtained (ROC) and the area under the curve (AUC) was compared for three different diagnostic criteria: PSV VAo, VAo/VA1, and VAo/VA2 PSV ratio. RESULTS A total of 386 vertebral arteries were angiographically examined and VAo stenosis 50‐99% was found in 36 (9%) vessels. The PSV VAo was the most accurate diagnostic parameter with an AUC .821 ± .052 (SE) (CI: .72, .92). A PSV of 114 cm/second maximized sensitivity (71%) and specificity (90%). CONCLUSION Our results support the use of PSV as a diagnostic criterion for VAo stenosis compared to a PSV ratio of VAo/V1 and VAo/V2.
Event‐Related fMRI of Inhibitory Control in the Predominantly Inattentive and Combined Subtypes of ADHD
Authors: Solanto Mary V. , Schulz Kurt P. , Fan Jin , Tang Cheuk Y. , Newcorn Jeffrey H. 
Published: October 2009

ABSTRACTBACKGROUND AND PURPOSE To examine the neurophysiological basis for the pronounced differences in hyperactivity and impulsiveness that distinguish the predominantly inattentive type of attention‐deficit/hyperactivity disorder (ADHD‐PI) from the combined type of the disorder (ADHD‐C). METHODS Event‐related brain responses to a go/no‐go test of inhibitory control were measured with functional magnetic resonance imaging (fMRI) in 11 children with ADHD‐C and 9 children with ADHD‐PI, aged 7 to 13 years, who were matched for age, sex, and intelligence. RESULTS There were no significant group differences in task performance. Children with ADHD‐C and ADHD‐PI activated overlapping regions of right inferior frontal gyrus, right superior temporal lobe, and left inferior parietal lobe during inhibitory control. However, the magnitude of the activation in the temporal and parietal regions, as well as in the bilateral middle frontal gyrus, was greater in children with ADHD‐PI than those with ADHD‐C. Conversely, children with ADHD‐C activated bilateral medial occipital lobe to a greater extent than children with ADHD‐PI. CONCLUSIONS The results provide preliminary evidence that phenotypic differences between the ADHD‐C and ADHD‐PI subtypes are associated with differential activation of regions that have previously been implicated in the pathophysiology of ADHD and are thought to mediate executive and attentional processes.
Self‐Referral of Imaging Does Not Imply Overutilization
Authors: Hutchinson Michael , Chawluk John B. , Gomez Camilo , Greenberg Jack , Hussey Francis D. , Preston William G. , Zimmerman Earl 
Published: October 2009

ABSTRACT For several years, some sectors of the specialty of Radiology have complained about the practice of self‐referral, where a nonradiologist physician provides and interprets an imaging procedure. It is argued that such practice leads to increased costs since a physician will overutilize technology because of financial incentives. Here we review the literature. The most extensive analysis to date is at odds with the conclusions drawn in the older literature in that it provides little, if any, evidence for overutilization. We performed our own investigation using a poll study and found no suggestion of overutilization in 33 self‐referring neurologists when compared with 900 neurologists who referred imaging to radiologists. The main period of growth in demand for imaging was between 1999 and 2002. Since 2002 there has been a steep decline in the rate of growth, so that it is possible to predict roughly zero growth in MRI utilization by 2009 without any intervention. It is shown why the rise in demand for imaging studies cannot be explained by self‐referral, and it is argued that the sudden expansion of demand 8 years ago was caused by simultaneous technological improvements in the 3 major imaging modalities. Finally, it is shown how self‐referral may actually reduce costs by facilitating the transfer of care from the hospital and ER to the office.
Ear Necrosis Resulting from the Endovascular Onyx‐18 Embolization of a Dural Arteriovenous Fistula Fed by the Posterior Auricular Artery
Authors: Jankowitz Brian T. , Vora Nirav , Jovin Tudor , Horowitz Michael 
Published: October 2009

ABSTRACTBACKGROUND AND PURPOSE The treatment of a dural arteriovenous fistula (DAVF) can involve surgery, radiosurgery, or endovascular embolization. New embolization techniques and agents have expanded the role of endovascular treatment. METHODS We report the endovascular embolization with Onyx‐18 of a DAVF fed by the posterior auricular artery. RESULTS The DAVF was successfully embolized; however, the patient's ear developed ischemic necrosis of the superolateral pinna. CONCLUSIONS Onyx‐18 can provide high rates of success in the treatment of DAVFs in well‐selected patients. Risks of end organ ischemia must be considered during endovascular embolization and when counseling patients regarding procedural risk.
Subcortical Vascular versus Amnestic Mild Cognitive Impairment: Comparison of Cerebral Glucose Metabolism
Authors: Seo Sang Won , Cho Sang Soo , Park Aram , Chin Juhee , Na Duk L. 
Published: October 2009

ABSTRACTBACKGROUND AND PURPOSE Most studies on mild cognitive impairment (MCI) have been focused on amnestic MCI (aMCI) that is the preclinical stage of Alzheimer's disease (AD). In contrast, only a few studies have involved patients in the preclinical stages of subcortical vascular dementia (subcortical vascular MCI, svMCI). We tried to compare the overall glucose metabolism in patients with svMCI with that of patients with aMCI. METHODS We compared the regional metabolic patterns shown on 18 F‐FDG (fluro deoxy glucose) positron emission tomography (PET) images from 18 patients with svMCI with those from 25 aMCI patients matched for age, sex, education, and mini‐mental state examination (MMSE) score and with those from 35 healthy subjects using a voxel‐wise analysis. SPM 2 was used for statistical analysis. RESULTS Relative to normal controls, the hypometabolic regions in the aMCI patients were in the bilateral parahippocampal, bilateral posterior cingulate, left superior temporal gyri, left inferior parietal lobule, and right inferior frontal gyrus while those in the svMCI patients were located in the thalamus, insula, superior temporal gyrus, anterior cingulate gyrus, cingulum, right basal ganglia, cerebellum, and brainstem. A direct comparison of glucose metabolism between svMCI and aMCI showed that the glucose hypometabolism in patients with svMCI was more severe in the thalamus, brainstem, and cerebellum. CONCLUSION Our study suggested that svMCI was distinct from aMCI in terms of neuropsychological and PET findings, which may explain their clinical manifestations.
Visual Symptoms in the Heidenhain Variant of Creutzfeldt‐Jakob Disease
Authors: Cornelius Jason R. , Boes Christopher J. , Ghearing Gena , Leavitt Jacqueline A. , Kumar Neeraj 
Published: October 2009

ABSTRACTBACKGROUND AND PURPOSE The distinguishing feature in Heidenhain variant Creutzfeldt‐Jakob disease (HvCJD) is the presence of visual symptoms preceding the appearance of other clinical manifestations. The purpose of this report is to describe the broad range of visual symptomatology in a patient with HvCJD. METHODS The authors describe the clinical, neuroimaging, and EEG features of a 51‐year‐old man with progressive visual symptoms that were most likely due to HvCJD. Migraine and epilepsy were initial diagnostic considerations. RESULTS Our patient presented with progressive visual decline and superimposed spells of visual dysfunction that had complex characteristics. Evolution of an abnormal signal in the parieto‐occipital cortex on diffusion weighted MRI, changes on EEG, and clinical course were consistent with HvCJD. CONCLUSIONS HvCJD should be considered in all patients who present with unexplained visual phenomena. A remarkable spectrum of visual disturbances can be seen. Close follow‐up as well as serial MRI and EEG can help clarify the underlying disease process. Diffusion‐weighted and FLAIR sequences should be included in the MRI protocol.
Quantitative Magnetic Resonance Angiography in the Evaluation of the Subclavian Steal Syndrome: Report of 5 Patients
Authors: Bauer Andrew M. , Amin‐Hanjani Sepideh , Alaraj Ali , Charbel Fady T. 
Published: October 2009

ABSTRACTBACKGROUND AND PURPOSE The indications for surgical or endovascular treatment of patients with subclavian stenosis (SS) or occlusion remain controversial. Multiple studies have shown that in most patients, SS results in steal that is evident radiographically, but requires no treatment. METHODS This report describes 5 cases of SS, analyzed with phase contrast quantitative MRA (QMRA). QMRA provides quantitative blood flow data previously unavailable. A quantitative ischemic forearm challenge is also introduced using the QMRA technique. RESULTS A basilar flow index, basilar artery (BA) flow as a percentage of total intracranial flow was defined. This varied from 12.6% to 20.4%. All patients in this report had VA flow reversal. None had BA flow reversal CONCLUSION This report features novel methods using QMRA to identify ischemic patterns in the BA indicative of significant subclavian steal syndrome (SSS) in patients with SS.
Early Contrast‐Enhanced Magnetic Resonance Imaging with Fluid‐Attenuated Inversion Recovery in Multiple Sclerosis
Authors: Kataoka Hiroshi , Taoka Toshiaki , Ueno Satoshi 
Published: October 2009

ABSTRACTOBJECTIVE Contrast‐enhanced magnetic resonance imaging (MRI) with fluid‐attenuated inversion recovery (contrast FLAIR) is particularly useful for the detection of meningeal lesions. However, whether contrast FLAIR is useful in multiple sclerosis (MS) remains uncertain. This study evaluated the usefulness of contrast FLAIR in MS. PATIENTS AND METHODS We prospectively studied the clinical histories and brain MRI studies of 6 patients with clinically definite MS diagnosed according to the new McDonald criteria. Contrast FLAIR (repetition time [TR] 9,000 ms; echo time [TE] 120 ms; inversion time [TI] 2,200 ms; 5‐mm slice thickness, with a 1‐mm interslice gap) was obtained with the use of a bolus of gadolinium diethylenetriamine pentaacetic acid. RESULTS Three enhancing plaques located in the periventricular or juxtacortical areas showed higher intensity on contrast FLAIR than on other MR sequences. In contrast, 8 enhancing plaques in the deep white matter or infratentorial areas showed no increased signals on contrast FLAIR. CONCLUSION Our findings suggest that early contrast‐enhanced imaging with FLAIR may be helpful for the further detection of MS plaques, particularly those located in periventricular and juxtacortical lesions.
Perfusion SPECT Findings in a Suspected Case of Rasmussen Encephalitis
Authors: Tessonnier Laetitia , Thomas Pierre , Benisvy Danielle , Chanalet Stephane , Chaborel Jean Philippe , Bussière Françoise , Darcourt Jacques 
Published: October 2009

ABSTRACT We report the case of a 35‐year‐old who was referred for brain perfusion single photon emission computed tomography (SPECT) for pharmacoresistant epilepsy. Her medical history included brain surgery for an inflammatory lesion of unknown origin at age 23 before partial epilepsy occurred. The seizures became refractory to standard antiepileptic drugs and she developed epileptic negative myoclonus of the right upper limb, nocturnal motor seizures, and progressive intellectual impairment. Neurological symptoms slowly worsened with mild aphasia and right visual neglect. Inter‐ictal brain SPECT showed decreased cerebral blood flow on the left hemisphere corresponding on magnetic resonance imaging (MRI) with moderate left hemiatrophy, a left frontal defect in accordance with the history of surgery, and a crossed cerebellar diaschisis. Clinical and imaging data were in favor of a late‐onset form of Rasmussen encephalitis. Rasmussen syndrome is a rare unilateral devastating disease with childhood onset that can also occur in adulthood, characterized by intractable epileptic seizures associated with progressive neurological deterioration and unilateral progressive atrophy. Brain perfusion SPECT can speed up the diagnosis when exhibiting a strictly unilateral hemispheric hypoperfusion in such a clinical context. It can also guide brain biopsy in cases of inconclusive MRI.
Reversible Cytotoxic Edema in a Cirrhotic Patient Following TIPS
Authors: Babington James R. , Stahl Justin H. , Coy David L. 
Published: October 2009

ABSTRACT The authors report the magnetic resonance imaging (MRI) findings in a 52‐year‐old man with cirrhosis from chronic hepatitis C who developed episodic acute hepatic encephalopathy Type C following placement of transjugular intrahepatic portosystemic shunt (TIPS). Brain MRI revealed hyperintense T2 signal and restricted diffusion distributed through the cerebral cortex. The patient's mentation improved with treatment of his hyperammonemia. Brain MRI performed 5 months later revealed diffuse cerebral atrophy and new areas of hyperintense T2 signal in the cerebral white matter. The cortical signal abnormalities and low apparent diffusion coefficient values on the initial MRI resolved with exception of a mild amount of hyperintense FLAIR signal in the cingulate cortex. Acute hepatic encephalopathy following portosystemic shunting—either from placement of TIPS or from development of spontaneous shunts—is a widely recognized complication of portal hypertension and cirrhosis. We report MRI findings of reversible cytotoxic edema in a patient with acute hepatic encephalopathy following placement of TIPS.
Consensus Conference on Intracranial Atherosclerotic Disease: Rationale, Methodology, and Results
Authors: Qureshi Adnan I. , Feldmann Edward , Gomez Camilo R. , Johnston S. Claiborne , Kasner Scott E. , Quick Donald C. , Rasmussen Peter A. , Suri M. Fareed K. , Taylor Robert A. , Zaidat Osama O. 
Published: October 2009

ABSTRACT The consensus conference on intracranial atherosclerotic disease (ICAD) identifies principles of management, and research priorities in various aspects upon which leading experts can agree (using “Delphi” method). ICAD is more prevalent in Asian, Hispanic, and African‐American populations. Patients who have had a stroke or transient ischemic attack (TIA) attributed to stenosis (50‐99%) of a major intracranial artery face a 12‐14% risk of subsequent stroke during the 2‐year period after the initial ischemic event, despite treatment with antithrombotic medications. The annual risk of subsequent stroke may exceed 20% in high‐risk groups. The medical treatment of patients with symptomatic ICAD is directed toward: 1. Prevention of intraluminal thrombo‐embolism, 2. plaque stabilization and regression, and 3. management of atherogenic risk factors. In patients with ICAD, short‐term and long‐term anticoagulation (compared with aspirin) have not shown to be beneficial. The current guidelines recommend that aspirin monotherapy, the combination of aspirin and extended release dipyridamole, and clopidogrel monotherapy (rather than oral anticoagulants) are all acceptable options in patients with non‐cardioembolic ischemic stroke and TIA. Overall, the subgroup analysis from randomized trials provides evidence about benefit of aggressive atherogenic risk factor management among patients with ICAD. Intracranial angioplasty with or without stent placement has evolved as a therapeutic option for patients with symptomatic ICAD, particularly those with high‐grade stenosis with recurrent ischemic symptoms and/or medication failure. A matched comparison between medical‐treated patients in the Warfarin Aspirin Symptomatic Intracranial Disease (WASID) study and stent‐treated patients in the National Institutes of Health intracranial stent registry concluded that stent placement may offer benefit in patients with 70‐99% stenosis. The 5‐year, multicenter, prospective, randomized Stenting and Aggressive Medical Management for Preventing Recurrent stroke in Intracranial Stenosis study supported by the National Institutes of Health is currently comparing stent placement with intense medical management with intense medical management alone in patients with high‐grade symptomatic intracranial stenosis. The proceedings of the consensus conference provide a template for standardizing management of patients with ICAD and determining research priorities.
Epidemiology of Intracranial Stenosis
Authors: Suri M. Fareed K. , Johnston S. Claiborne 
Published: October 2009

ABSTRACT Intracranial stenosis is a common etiology for ischemic stroke. Due to limitations of imaging studies, there are limited data on the prevalence of symptomatic and asymptomatic intracranial stenosis. Intracranial stenosis is more prevalent in Asian, Hispanic, and African‐American populations. The reported proportion of patients with symptomatic intracranial stenosis among those hospitalized for ischemic cerebral events varies from 1% in non‐Hispanic whites to as high as 50% in Asian populations. In population‐based studies, the estimated prevalence of symptomatic intracranial disease varies from 1 in 100,000 for whites to 15 in 100,000 in African Americans. A Chinese population‐based study reported intracranial stenosis in 7% of the population aged more than 40 years. Autopsy studies have noted intracranial atherosclerotic disease in about 23% of population in the 6th decade and 80% of population in the 9th decade of life. Angiotensin‐converting enzyme polymorphisms, plasma endostatin/vascular endothelial growth factor ratio, glutathione S‐transferase omega‐1 gene polymorphism, and plasma homocysteine levels are non‐modifiable risk factors noted to be associated with intracranial stenosis. Hypertension and serum lipid profile are major modifiable risk factors, whereas sickle cell disease is an uncommon risk factor that can be managed to reduce risk. Associations of intracranial atherosclerosis with diabetes mellitus, metabolic syndrome, Alzheimer's disease, aortic plaques, radiotherapy, and meningitis are less well documented.
Natural History of Symptomatic Intracranial Arterial Stenosis
Authors: Kasner Scott E. 
Published: October 2009

ABSTRACT Patients who have had a stroke or transitory ischemic attack (TIA) attributed to stenosis (50‐99%) of a major intracranial artery face a 12‐14% risk of subsequent stroke during the 2‐year period after the initial ischemic event, despite treatment with antithrombotic medications. Most of this risk accrues during the first year. Some patients are at substantially greater risk, particularly those with a severe (70‐99%) stenosis, those who have recently had an ischemic event, and women. Patients may also be at high risk if they had an initial stroke rather than TIA or if they have symptoms precipitated by hemodynamic maneuvers. The annual risk of subsequent stroke may exceed 20% in these high‐risk groups.