bluuebunny/crossref_metadata_2025 huggingface dataset:
Clinical Cerebrovascular Applications of Arterial Ultrasound Volume Flow Rate Estimates
Authors: Knappertz Volker A. , Tegeler Charles H. , Myers Lawrence G.
Published: February 2016

A variety of disorders affect cerebral hemodynamics. Volume flow rate (VFR) estimates now allow accurate quantification of the effect of cerebrovascular lesions on the conduit vessels, with excellent in vivo and in vitro correlation. Four selected cases with VFR data and angiographic correlation are presented to illustrate potential clinical uses of this method. The VFR estimates were obtained with a color M‐mode‐based velocity imaging technique, which uses time‐domain processing (P‐700 Color Velocity Imaging System, Philips Ultrasound International, Irvine, CA). In a patient awaiting coronary artery surgery, with unilateral internal carotid artery occlusion and contralateral angiographic stenosis (50‐80%, reader variation), the baseline and acetazolamide‐challenged common carotid artery VFRs showed excellent conduit function ipsilateral to this stenosis. Thus, the angiographic stenosis did not have significant hemodynamic effects and endarterectomy was avoided. In a patient with an arteriovenous malformation fed by the left vertebral and left external carotid arteries, high in the left cervical region, VFR estimates of two to three times normal predicted the feeding vessels, influenced management, and proved helpful in follow‐up. In a patient with subclavian steal syndrome, VFR estimates quantified the steal after brachial hyperemia. Finally, in a patient with delayed vasoconstriction after subarachnoid hemorrhage, very low VFR estimates preceded clinical deterioration. Quantification of hemodynamic changes with VFR estimates was useful for the diagnosis, management, and follow‐up of these patients with four types of cerebrovascular disease, and should be applicable in many others.
Volumetric Measurement of Multifocal Brain Lesions: Implications for Treatment Trials of Vascular Dementia and Multiple Sclerosis
Authors: Broderick Joseph P , Narayan Suresh , Gaskill Mary , Dhawan Atam P , Khoury Jane
Published: February 2016

This pilot study examined the reproducibility of serial magnetic resonance (MR) measurements of brain, ventricular, sulcal, and lesion volumes in patients with ischemic brain disease using an image analysis protocol designed at the University of Cincinnati. Five patients with a clinical history of brain ischemia had two separate MR brain imaging studies using the standard clinical MR imaging protocol at the University of Cincinnati Medical Center. The MR images on both film and tape were digitized and then analyzed according to the standardized image analysis protocol. Based on tape data, variability in volume measurements between the two MR studies, as measured by the coefficient of variation, ranged from 1% for intracranial volume to 8% for ventricular volume. Variability based on film data was slightly greater, ranging from 2% for intracranial volume to 12% for lesion volume. As part of a multicenter treatment trial of vascular dementia, this method was then used to analyze MR films in 13 patients with vascular dementia who all had an MR study at baseline and at 1 year. The mean annual change in lesion volume was 4 ± 5 cm3 (a 24% increase from the baseline lesion volume); in ventricular volume, 7 ± 8 cm3 (a 10% increase from baseline); and in sulcal volume, 13 ± 25 cm3 (a 5% increase from baseline). This method of image analysis, using MR film or tape‐generated data, can provide reproducible serial measurements of brain, ventricular, sulcal, and ischemic lesion volumes. This method, if applied in randomized treatment trials of vascular dementia or multiple sclerosis, can be used to monitor disease progression and to evaluate the effectiveness of a given therapy.
Butterfly Vertebra
Authors: Delgado Alain , Mokri Bahram , Miller Gary M.
Published: February 2016

A 41‐year‐old man with low back pain and lumbar disc disease was found to have L‐3 butterfly vertebra on imaging studies as an incidental finding. This uncommon congenital anomaly of the vertebral column is usually asymptomatic and of no clinical significance. Awareness of this deformity and its imaging features is important diagnostically.
The Open Ring A New Imaging Sign in Demyelinating Disease
Authors: Masdeu Joseph C. , Moreira Joseph , Trasi Sunil , Visintainer Paul , Cavaliere Rossella , Grundman Michael
Published: February 2016

Because demyelinating disease of the brain occasionally presents with large ring‐enhancing lesions on computed tomography (CT) scans and magnetic resonance images (MRis), the authors sought to determine whether the ring pattern differed from that found in other common brain lesions with ring enhancement. Published MRI and CT scans of patients with adrenoleukodystrophy (23), and multiple sclerosis or similar demyelinating disorders (21), as well as a variety of tumors (44) and infections (44) matched to the demyelinating lesions by year of publication, in which ring enhancement was evident, were photographed. Photographs without diagnostic identification were presented randomly to two independent observers. The observers rated the contrast enhancement pattern as (1) open ring, with enhancement in the border of the lesion abutting the white matter; (2) closed ring; or (3) uncertain. For all diagnostically certain cases (n = 112), interrater agreement was excellent (κ = 0.75). As an average of the two reviewers, scans for 11 of 132 cases were read as uncertain; 89% of adrenoleukodystrophy cases, 41% of the multiple sclerosis cases, 3% of tumors, and 9% of infections were classified as having the open‐ring pattern. Overall, 66% of demyelinating lesions had an open‐ring pattern compared with 7% of the nondemyelinating lesions (χ2 = 41.2, p < 0.0001 ). An open‐ring pattern of enhancement is more likely to be associated with demyelinating lesions than with nondemyelinating lesions .
Magnetic Resonance Imaging of Syrinx Associated with Intramedullary Metastases and Leptomeningeal Disease
Authors: Phuphanich Surasak , Zachariah Sally , Zachariah Babu , Ku Ni Ni , Reed Murtagh F
Published: February 2016

Intramedullary spinal cord metastasis with an associated syrinx diagnosed by magnetic resonance imaging (MRI) is described. The patient had documented simultaneous leptomeningeal spread of malignant cells and intramedullary spinal cord metastasis with hyalinized blood vessels, venous dilatation, and cavitation detected by autopsy. Metastasis to the spinal cord is unusual, but well described. Syrinx associated with intramedullary spinal cord metastasis has been detected rarely. MRI of syrinx and intramedullary spinal cord metastasis, and the possible pathogenesis of these lesions are discussed.
Extracranial Intravascular Vasodilatory Response to Acetazolamide and Magnetic Resonance
Authors: Levine Ross L. , Turski Patrick A. , Turnipseed William D. , Grist Thomas
Published: February 2016

Cerebral vasodilatory testing provides an important measure of both the hemodynamic significance of arterial occlusive disease and the adequacy of collateral pathways . This study measured the extracranial intravascular volume flow rate response to acetazolamide using phase‐contrast magnetic resonance angiography. From 10 patients with unilateral carotid transient ischemic attacks (TIAs), a total of 18 extracranial carotid arteries (10 symptomatic, 8 asymptomatic, 2 occluded) and 19 extracranial vertebral arteries were studied . Patients were free of large‐vessel intracranial stenoses, evident areas of ischemic infarction, evident areas of nonspecific white matter change, and hemodynamic or lowflow induction of TIA symptomatology. Asymptomatic carotid volume flow rates rose from 1 51 ± 19 (standard error of mean) to 220 ± 26 ml/min while symptomatic flow rates rose from 106 ± 22 to 145 ± 25 ml/min . Dominant vertebral volume flow rates rose from 128 ± 23 to 160 ± 22 ml/min while nondominant rates rose from 40 ± 12 to 61 ± 15 ml/min. Carotid volume flow rates were inversely proportional to percent stenosis for both baseline (r = 0 .51, p < 0 .02) and acetazolamide (r = 0.81, p < 0 .001) data . Baseline‐plus‐acetazolamide volume flow rate techniques safely measure intravascular vasodilatory responses. Intracranial measurement techniques are being developed to further study cerebrovascular reserve using phase‐contrast magnetic resonance angiography .
Preclinical Evaluation of SPECT Imaging with 131∣–Labeled Monoclonal Antibody SZ39 in Nude Mice Bearing Human Glioma Xenografts
Authors: Lan Qing , Huang Qiang , Bao Shiyao
Published: February 2016

The imaging characteristics of monoclonal antibody SZ39 against glioma were evaluated in glioma–bearing nude mice. Monoclonal antibody SZ39 is a murine lgG2a that reacts with a glycoprotein epitope (molecular weight 180,000), a human glioma–associated membrane antigen. Monoclonal antibody SZ39 was labeled with 131∣using a modified chloramine T method. Each glioma–bearing nude mouse was given 50 µCi/40 µg of the experimental agent, 131∣–labeled monoclonal antibody, or 50 µCi/46 µg of a control agent, 131∣–labeled monoclonal antibody C50, an antibody against colon cancer. Single–photon emission computed tomography (SPECT) was performed every 24 hours in the first week after administration. Glioma–bearing nude mice were killed in groups of 3 at 24 hours and daily up to 72 hours. The ratio of radioactivity uptake in glioma to normal organs was calculated. After administration of the labeled SZ39, glioma was visualized with SPECT on days 1 to 7, particularly at 72 hours. There was no accumulation of radioactivity in glioma with the labeled C50 antibody. All glioma–organ ratios increased with time. At 72 hours, the ratio of glioma to brain was 22.46 and of the other organs was 2.64 on average. SZ39 had a relatively low endocytosis rate and was favorable for 131∣ labeling. These characteristics were helpful to reduce free 131∣ in the blood and reduce the uptake by other organs. The results suggest that 131∣–labeled SZ39 selectively accumulates in glioma, representing a potential strategy for SPECT imaging of these lesions.
Intravascular Ultrasound Imaging of Human Cerebral Arteries
Authors: Ravalli Stefano , LiMandri Giuseppe , Tullio Marco R. Di , Marboe Charles C. , Boxt Lawrence , Sacco Ralph L. , Schwartz Allan , Homma Shunichi
Published: February 2016

The aim of this study was to assess the feasibility of imaging cerebral arteries in vitro with intravascular ultrasound and to establish a correlation between echographic images and corresponding histological architecture. Intravascular ultrasound imaging was performed using a 30‐MHz, 4.3F ultrasound probe. Twenty‐two arterial segments were obtained at autopsy from 6 patients and were imaged fresh. Arteries were then processed for histological examination and comparisons were made between echographic and histological findings. The correlation between luminal area measurements as determined histologically and by intravascular ultrasound was tested by linear regression analysis. Intravascular ultrasound demonstrated a three‐layered appearance in normal cerebral arteries but not in those affected by severe atherosclerosis. Overall, ultrasound correctly identified the presence of a plaque in 83% of patients. Intravascular ultrasound sensitivity and specificity, respectively, were 100 and 80% for calcium deposits and 83 and 75% for fibrous tissue. Intravascular ultrasound and histological measurements correlated well for the determination of luminal area (r = 0.89). Intravascular ultrasound provides accurate characterization of the arterial lumen and geometry, as well as the presence and histological features of atherosclerotic plaque. Thus, it appears to have a great potential for an earlier and more accurate diagnosis of atherosclerosis and may serve to guide new interventional techniques being utilized in the treatment of cerebrovascular diseases.
Magnetic Resonance and Single‐Photon Emission Tomography Findings in a Pair of Twins Discordant for Alzheimer's Disease
Authors: Geroldi Cristina , Frisoni Giovanni B. , Beltramello Alberto , Weiss Claudia , Bianchetti Angelo , Pizzolato Gilberta , Ferlin Giorgio , Trabucchi Marco
Published: February 2016

The value of functional and morphological neuroimaging in the early diagnosis of Alzheimer s disease (AD) is still debated. Described here are cerebral perfusion and linear measures of medial temporal lobe atrophy in 2 monozygotic twins discordant for AD who were investigated with technetium 99m‐hexamethylpropyleneamineoxime single‐photon emission tomography (SPET) and magnetic resonance (MR) imaging. Both showed pathological cortical perfusion findings on SPET, while medial temporal lobe atrophy was present only in the affected twin. MR measures of medial temporal lobe atrophy have greater agreement with clinical data than do SPET measures of cerebral perfusion. Evaluation of atrophy may be useful in the early diagnosis of AD.
Detection of Vasospasm by Transcranial Doppler Sonography
Authors: Wozniak Marcella A. , Sloan Michael A. , Rothman Michael I. , Burch Christina M. , Rigamonti Danielle , Permutt Thomas , Numaguchi Yuji
Published: February 2016

Little information exists on the utility of transcranial Doppler sonography (TCD) in detecting anterior (ACA) and posterior cerebral artery (PCA) vasospasm following subarachnoid hemorrhage. During the period at risk for vasospasm, 53 patients with subarachnoid hemorrhage who had technically adequate TCD performed within 24 hours of cerebral angiography, allowing evaluation of 87 ACAs and 84 PCAs, were studied. ACA and PCA vasospasm were defined by mean blood flow velocities of at least 120 cm/ sec and at least 90 em/sec, respectively. For detection of ACA vasospasm, sensitivity was 18% and specificity was 65%. For PCA vasospasm, sensitivity was 48% and specificity was 69%. False‐positive findings for occlusion accounted for 12 (92 %) of 13 ACA false‐positive results and 7 (37%) of 19 PCA false‐positive results, and were most often due to anatomical factors and operator error or inexperience. After exclusion of both true‐positive and false‐positive findings for occlusion and changes in the diagnostic criterion to at least 130 cm/sec for ACA vasospasm and at least 110 cm/sec for PCA vasospasm, specificity improved for both types of vasospasms (100 and 93%, respectively). However, the sensitivity of TCD to detect ACA and PCA vasospasm is limited by a variety of anatomical, technical, and other factors. It is concluded that TCD is highly specific in detecting both ACA and PCA vasospasm in arteries that can be insonated.
Phase‐Contrast Magnetic Resonance Angiography for the Determination of Cerebrovascular Reserve
Authors: Patrick James T. , Fritz Joseph V. , Adamo John M. , Dandonna Paresh
Published: February 2016

Cerebrovascular reserve (CVR) is the potential for cerebral arteriolar dilatation to occur, in response to decreased cerebral perfusion pressure, in order to maintain constant cerebral blood flow. Diminution or absence of CVR is considered a risk factor for stroke. Current methods for determining CVR include singlephoton emission computed tomography, positron emission tomography and transcranial Doppler (TCD) ultrasonography. However, significant advantages could derive from the utilization of magnetic resonance angiography (MRA) based on the concurrent acquisition of hemodynamic information (CVR and collateral flow) with phase‒contrast (PC) techniques and vascular morphology with three‒dimensional, time‒of‒flight methods. With a 1.5‒T scanner and acetazolamide (AZM), an arteriolar dilator, CVR was determined in 7 normal subjects. Mean flow velocity in the middle cerebral arteries was determined by PC MRA before and after AZM administration. For comparative purposes, mean flow velocities in the same middle cerebral arteries were determined by TCD before and after AZM administration. The mean flow velocities were as follows (mean ± standard deviation, n = 7): 40 ± 8 (PC MRA) versus 61 ±10 cm/sec (TCD) before AZM treatment and 58 ±11 (PC MRA) versus 85 ±15 cm/sec (TCD) after AZM administration. The increase in mean flow velocity (before vs after AZM), that is, the CVR, was 45 ±11 % as shown by PC MRA and 39 ± 14% as shown by TCD. Although significant differences were present between the mean flow velocities measured before and those after AZM administration, as determined by PC MRA and TCD, the CVR was not significantly different (45 vs 39%, respectively). These preliminary results suggest that PC MRA may be a method for determining CVR.
Clinical Significance of Increased Uptake of HMPAO on Brain SPECT Scans in Acute Stroke
Authors: Alexandrov Andrei V. , Ehrlich Lisa E , Bladin Christopher F. , Black Sandra E.
Published: February 2016

Single‐photon emission computed tomography (SPECT) with 99mtechnetium‐hexamethylpropylamineoxirne (HMPAO) non‐invasively shows brain perfusion in patients after acute stroke. However, the clinical significance of the increased HMPAO uptake remains unclear. In this study, consecutive patients with hemispheric hemorrhagic and ischemic stroke admitted to the hospital were evaluated prospectively. The increased uptake of HMPAO was determined by visual analysis of SPECT images. The pathogenic mechanism of ischemic stroke was determined using the clinical and computed tomography (CT) criteria including the Toronto Embolic Scale. Of the 500 consecutive patients with acute hemispheric stroke, SPECT was performed in 458 at a mean time of 5 ± 7 days after the onset of symptoms. A strong association was found between SPECT perfusion patterns and pathogenic subtypes of stroke (p < 0.0001). Thus, in 95% of patients with intracerebral hemorrhage the focal absence of perfusion was found, and 26% of lacunar infarctions presented with a normal SPECT appearance. The mean volume of lacunar lesions that did not produce significant abnormalities on SPECT was 2.5 ± 1.2 ml. Increased HMPAO uptake was associated with a cardioembolic mechanism of stroke: High and mixed perfusion patterns were present subacutely in 29% of patients with cardioembolic stroke, compared to 15% of patients with other types of ischemic stroke (p ≤ 0.0006). The increased uptake of HMPAO on SPECT as determined by visual analysis is associated with a cardioembolic mechanism of cerebral ischemia, which could be explained by glutathione‐mediated trapping of the tracer during reperfusion and later in newly developed granulation tissue. HMPAO‐SPECT may help in early management decisions since it indicates stroke pathogenesis and evolution.
Serial Transcranial Doppler Monitoring after Transient Ischemic Attack
Authors: Eicker B. Martin , von Lorentz Johannes , Paulus Walter , Tegeler Charles H.
Published: February 2016

The natural course of ultrasonically detectable microembolism in patients with a symptomatic extracranial atherosclerotic lesion is not completely understood. Furthermore, the potential impact of therapeutic management on microemboli detection is anecdotal. A 58‐year‐old man who experienced a left‐hemisphere transient ischemic attack presented with an extracranial ipsilateral high‐grade carotid stenosis. He was studied 12 times in 12 months during different medical management, during which time he was symptom free, even though transcranial Doppler evidence of microemboli continued for 5 months.
Magnetic Resonance Imaging of Corticobasal Degeneration
Authors: Hauser Robert A. , Murtaugh F. Reed , Akhter Kauser , Gold Michael , Olanow C. W.
Published: February 2016

Corticobasal degeneration (CBD) is an adult–onset, progressive parkinsonian syndrome with strikingly asymmetrical features, and signs and symptoms referable to both cerebral cortex and basal ganglia. Although once considered rare, it is now recognized with increasing frequency during life. Eight patients with clinically diagnosed CBD and 8 age– and sex–matched patients with Parkinson's disease underwent high–field–strength magnetic resonance imaging (MRI) of the brain. MRIs were graded by a blinded neuroradiologist using a semiquantitative (0–3) scale. MRI of patients with CBD revealed significantly greater T2–weighted signal hypointensity in the putamena and globi pallidi, and ventricular enlargement. When specifically sought, asymmetrical cortical atrophy was identified in 5 of 8 CBD patients. Increased T2–weighted lenticular signal hypointensity, ventricular enlargement, and asymmetrical cortical atrophy are supportive MRI findings of CBD.
Primary Diffuse Leptomeningeal Gliomatosis with Signs of Increased Intracranial Pressure and Progressive Meningeal Enhancement on MRI
Authors: Park Justin S. , Van den Noort Stanley , Kim Ronald C. , Walot Irwin , Licht Harvey
Published: February 2016

A 21‐year‐old woman presented with a 5‐month history of meningeal signs and evidence of intracranial hypertension and, as shown by magnetic resonance imaging (MRI), progressively more extensive meningeal enhancement, particularly within the spinal canal. Autopsy disclosed the presence of primary diffuse leptomeningeal gliomatosis with spinal cord predominance, possibly arising within heterotopic leptomeningeal glial tissue in the cervical region. No parenchymal primary lesion was identified. MRI with gadolinium appears to be the imaging modality of choice for the early detection of primary diffuse leptomeningeal neoplasia.
Stenting: A New Approach to Carotid Dissection
Authors: DeOcampo Jose , Brillman Jon , Levy David I.
Published: February 2016

A patient with bilaterally occluded internal carotid arteries had a right hemispheric stroke followed by a left cerebral infarction, secondary to dissection from fibro–muscular dysplasia, seen also in the vertebral arteries. The occluded left carotid was reopened and stents placed, with apparent reestablishment of left hemispheric blood flow. The speech and other deficits resolved. Although its use is under investigation, percutaneous balloon angioplasty with stents may be an appropriate intervention when other measures do not prevent progressive ischemic events.
Degeneration of the Pyramidal Tracts in Patients with Amyotrophic Lateral Sclerosis
Authors: Abe, Kazuo , Fujimura, Harutoshi , Kobayashi, Yasuo , Fujita, Norihiko , Yanagihara, Takehiko
Published: February 2016

To investigate focal hyperintensity in the internal capsule (1C) on magnetic resonance images (MRIs) and its clinical significance, 80 patients with amyotrophic lateral sclerosis (ALS) and 80 sex‐ and age‐matched normal control subjects were studied. On T2‐weighted images, hyperintense foci were found in the posterior part of the posterior limb (PL) of the 1C in 41 (51 %) of 80 control subjects. However, no subject showed increased signal intensities on proton density‐weighted images. Hyperintense foci were also observed in the posterior part of the PL of the IC on T2‐weighted images in 52 (65%) of 80 ALS patients and on proton density‐weighted images in 26 (65%) of 40 ALS patients; the abnormally intense foci were seen at the same anatomical location in the IC as those in the normal control subjects. On postmortem MRI, the abnormally intense foci were found in the posterior part of the PL of the IC in the formalin‐ fixed brains from 9 ALS patients. Three normal control subjects did not show signal intensity changes on postmortem MRI. On histological examination of 9 ALS brains, distinct myelin pallor and gliosis were found in the posterior third of the PL of the IC. Proton density‐weighted images appear to be useful to distinguish neuropathological changes in the corticospinal tract of ALS patients.
Transcranial Doppler in 178 Patients Before, During, and After Carotid Endarterectomy
Authors: Gossetti Bruno , Martinelli Ombretta , Guerricchio Renato , lrace Luigi , Benedetti-Valentini Fabrizio
Published: February 2016

From July 1991 to March 1995, 178 patients who underwent 198 carotid surgical repairs were investigated preoperatively, intraoperatively, and postoperatively by transcranial Doppler sonography (TCD). Preoperative TCD evaluation showed stenosis of the middle cerebral artery (MCA) in 4 patients (2.2%), siphon stenosis in 3 (1.6%), incomplete circle of Willis in 23 (12.9%), a decrease of mean blood flow velocity more than 70% of the basal value during digital common carotid compression in 31 (17.9%), and a critical reduction of vasomotor reactivity (no significant increase of mean blood flow velocity in the MCA during breath–holding test) in 34 (19.1%). Nine patients (5%) had surgery without preoperative angiography. In those patients the indication for surgery was based on color Doppler imaging and TCD investigations. Ninety surgical procedures were carried out under general anesthesia and 108 under locoregional anesthesia. In 37 surgeries (31.7%) a shunt was inserted: The use of a shunt was based on a decrease of mean blood flow velocity in the MCA below 50% of the basal value under general anesthesia or loss of consciousness combined with a decrease of mean blood flow velocity in the MCA higher than 70% of the basal value when locoregional anesthesia was employed. lntraoperative TCD monitoring showed a decrease of mean blood flow velocity in the MCA due to shunt malfunction in (8.3%) of 36 surgeries, turbulence of blood flow during declamping in 79 procedures (39.8%), and microembolic events in 10 patients (5%) that were related to one transient and one permanent neurological deficit. Another permanent deficit occurred in a patient without TCD signs. After surgery, TCD reliably detected an early asymptomatic occlusion of the carotid artery, hyperperfusion syndrome in 12 (6.0%), and an increase of vasomotor reactivity in 10 (29.4%) of 34 surgeries.
Extensive Reversible Brain Magnetic Resonance Lesions in a Patient with HELLP Syndrome
Authors: Feske Steven K. , Sperling Reisa A. , Schwartz Richard B.
Published: February 2016

A severe form of toxemia of pregnancy with microangiopathic hemolytic anemia, elevated /iver enzymes, and /ow platelets has been called the HELLP syndrome. A patient with the HELLP syndrome developed a severe, reversible encephalopathy. Brain computed tomography and magnetic resonance imaging showed abnormalities consistent with edema limited to the posterior circulation territory. The location of the lesions and their occurrence in the HELLP syndrome support suggestions that the vulnerability of posterior structures in eclamptic encephalopathy is due to a vascular susceptibility of the posterior circulation and that endothelial cell dysfunction plays an important role in the pathogenesis of eclamptic encephalopathy.
Clinical Significance of Intraplaque Hemorrhage in Carotid Artery Disease
Authors: Sillesen Henrik , Nielsen Tina
Published: February 2016

Previous research has indicated that intraplaque hemorrhage is a significant pathogenetic factor in carotid artery disease. The present study was undertaken to evaluate whether the clinical presentation of patients with carotid artery disease could be correlated to quantitative histologic analysis of surgically removed carotid specimens. Two–hundred–seventy patients undergoing carotid endarterectomy comprised the material Symptomatology was assessed preoperatively. After removal, the carotid plaques were analyzed histologically for relative volume content of hemorrhage, fatty tissue, fibrous tissue, and calcification. There was no difference between asymptomatic and symptom atic patients. However, when the time interval between onset of symptoms and surg~ ry was considered, plaques from patients with recent symptoms contained more hemorrhage compared with plaques from asymptomatic patients (p = 0.0045). The paper supports the theory of intraplaque hemorrhage being related to clinical events in carotid artery disease.
The Clinical Relevance of Cerebral Microemboli Detection by Transcranial Doppler Ultrasound
Authors: Zuilen, Erik V. , Van Gijn, Jan , Ackerstaff, Rob G. A.
Published: February 2016

This article reviews the studies on the detection of microemboli by transcranial Doppler ultrasound and the insight these studies have provided into the role of microemboli in the pathogenesis of symptomatic cerebral ischemia.
Multiple Cerebral Pseudoaneurysms and Hemorrhages: The Expanding Spectrum of Metastatic Cerebral Choriocarcinoma
Authors: Kalafut Mary , Vinuela Fernando , Saver Jeffrey L. , Martin Neil , Vespa Paul , Verity M. Anthony
Published: February 2016

Cerebral metastases occur in 10–20% of patients with choriocarcinoma. Although single oncotic and pseudoaneurysms have been reported, multiple pseudoaneurysms and hemorrhages are rare. A 33–year–old woman developed 10 intracerebral hemorrhages over a 30–day period. Angiogram showed multiple focal areas of delayed contrast washout in distal vessels. Autopsy revealed intravascular choriocarcinoma without true aneurysm formation. A diagnosis of choriocarcinoma should be considered for women of childbearing age presenting with cerebrovascular syndromes, especially those found to have cerebral aneurysm, pseudoaneurysm, and/or hemorrhage.
Quantitative Cerebral Perfusion SPECT in Systemic Lupus Erythematosus with Severe Central Nervous Involvement—Before and After Methylprednisolone Pulse Therapy
Authors: You Dong-Ling , Tzen Kai-Yuan , Kao Pan-Fu , Tsai Ming-Fong
Published: February 2016

Severe cerebral involvement may occur in patients with systemic lupus erythematosus. Methylprednisolone pulse therapy is a management choice for those with severe cerebral involvement. However, its effectiveness is uncertain. This article describes Tc‐99m HMPAO cerebral perfusion singlephoton emission computerized tomography to document the restoration of cerebral perfusion after methylprednisolone pulse therapy in a case of systemic lupus erythromatosus with severe cerebral manifestations.
Cerebello‐thalamo‐cerebral Diaschisis: A Case Report
Authors: Tecco Juan M. , Wuilmart Philippe , Lasseaux Laurence , Wikler David , Damhaut Philippe , Goldman Serge , Gilles Christian
Published: February 2016

This reports positron emission tomography and [18F]fluorodeoxyglucose (PET‐FDG) in a 69‐year‐old woman who underwent resection of the left cerebellar hemisphere for an acoustic neurinoma 17 years earlier. Functional impairment in cerebral cortical and subcortical structures was evaluated by studying the level of glucose metabolic activity at rest. Relative glucose metabolism was reduced in the prefrontal cortex contralateral to t he cerebellar lesion. Contralateral thalamic metabolism was reduced significantly. The results suggest that this phenomenon of “crossed cerebello‐thalamo‐cerebral diaschisis” is related to a funct ional depression of the cerebello‐thalamo‐cortical pathway.
A Preliminary Study Comparing the Sensitivity of Serial Monthly Enhanced MRI After Standard and Triple Dose Gadolinium‐DTPA for Monitoring Disease Activity in Primary Progressive Multiple Sclerosis
Authors: Filippi M. , Rovaris M. , Gasperini C. , Capra R. , Bastianello S. , Kuhne I. , Yousry T. A.
Published: February 2016

We performed this study to evaluate and compare the numbers of total and new enhancing lesions detected on serial monthly brain magnetic resonance imaging (MRI) after the injection of a standard dose (SO) and a triple dose (TO) of gadolinium‐OTPA (Gd) in patients with primary progressive multiple sclerosis (PPMS). Every 4 weeks for 3 months and in two separate sessions, MRI scans were obtained from 5 patients with PPMS, 5 (early) and 20 minutes (delayed) after SO (0.1 mmol/kg) or TO (0.3 mmol/kg) Gd injection. In 2 patients, T1‐weighted scans with a magnetization transfer pulse (MT) after SD and TD injection were also obtained. There were 13 enhancing lesions (5 of which were new) on the early SO scans, 15 (5 new) on the delayed SD scans, 17 (6 new) on the early TO scans and 18 (7 new) on the delayed TO scans. TO MRI scans detected more enhancing lesions than SO scans in 3 patients (two of them were those with the lowest disability). The application of the MT pulse did not change the numbers of enhancing lesions seen after the injection of SO and TO of Gd in the remaining two patients. No side effects were reported and no significant changes in blood test parameters were found throughout the study. Our results suggest that serial monthly TO MRI, delayed scanning, MT T1‐weighted scans or their combination, although safe, have a limited role for monitoring disease evolution in patients with PPMS.
Surface EMG and Myosonography in the Detection of Fasciculations: A Comparative Study
Authors: Wenzel Sabine , Herrendorf Gregor , Scheel Alexander , Kurth Christoph , Steinhoff Bernhard J. , Reimers Carl D.
Published: February 2016

Surface electromyography (EMG) and muscle sonography both facilitate the detection of fasciculations. This study was conducted to evaluate the prevalence of fasciculations in 10 lower extremity muscles in 58 subjects 47 ± 18 years of age without and 54 patients 52 ± 15 years of age with various neuromuscular diseases (3 with inflammatory myopathy, 15 with lower motor neuron disease, 22 with acquired and 11 with hereditary motor and sensory neuropathy (HMSN), and 3 with adrenomyeloneuropathy). When each muscle was screened by means of myosonography for 10 seconds, fasciculations were found in up to 8 muscles in 11 control subjects (19%) and in up to 10 muscles in 41 patients (76%). Within the same recording period surface EMG revealed fasciculations in 5 control subjects (9%) and 30 patients (56%), whereas during a recording time of 20 minutes fasciculations were detected in 55 (95%) control subjects and all patients. An amplitude of 400 µV proved to be the optimum cutoff between fasciculations for healthy subjects and patients with neuromuscular disease (accuracy, 74%). Myosonography allowed differentiation of both groups with an accuracy of 79%. Surface EMG was more liable to artifacts than myosonography. The average interval between subsequent fasciculations cannot be used to differentiate patients with acquired and hereditary polyneuropathy and with lower motor neuron disease. Long‐term surface EMG recording indicates fasciculations to occur in almost all patients with neuromuscular disease and the vast majority of healthy subjects. Muscle ultrasonography was more convenient and reliable than surface EMG in differentiating patients and healthy subjects.
Transcranial Power Mode Doppler Duplex Sonography of Intracranial Aneurysms
Authors: Griewing Bernd , Motsch Lillian , Piek Jüirgen , Schminke Ulf , Brassel Friedheim , Kessler Christof
Published: February 2016

The application of different color‐coding techniques in transcranial color‐coded duplex sonography (TCCD) was assessed for detection and measurement of the size of intracranial aneurysms. Thirty‐two consecutively examined patients with 36 angiographically verified cerebral aneurysms underwent TCCD with color Doppler flow imaging (CDFI), power Doppler imaging (PDI), and both methods with contrast enhancement. The diameters of the aneurysms were measured in comparable planes by means of angiography and TCCD‐PD with and without 400 mg/ml of the monosaccharide microparticle contrast agent Levovist. TCCD with CFD enabled detection of 27 of 36 aneurysms (75%), and PD depicted 29 aneurysms (80%). After administration of Levovist, an additional two aneurysms were detected with CFD and three with PD color coding. Measurements of aneurysm size obtained by means of PD with contrast enhancement corresponded more highly with angiographic findings than did measurements obtained with PD alone. Use of alternative color‐coding techniques with the addition of contrast agents increases the number of intracranial nonthrombosed aneurysms detectable with TCCD.
Distribution of Hematocrit Values After Aneurysmal Subarachnoid Hemorrhage
Authors: Giller Cole A. , Samson Duke , Giller Angela M. , Samson Duke
Published: February 2016

Low hematocrit values are common after subarachnoid hemorrhage and may be associated with elevated cerebral blood flow and transcranial Doppler ultrasound (TCD) velocities, which may confound the interpretation of velocity as an indicator of vasospasm. The exact distribution of hematocrit among a neurosurgical population would be useful in assessing the magnitude of this difficulty but has not been previously reported. A database containing hematocrit values recorded at TCD examinations over a period of 7 years was reviewed. Two thousand four hundred thirteen hematocrit values were recorded for 575 patients. The distribution of hematocrit values was recorded among patients and among TCD studies. Eighteen percent of the patient population achieved a hematocrit of 26% or less at some point in their hospital stay, whereas 57% of patients achieved a hematocrit of 30% or less. Six percent of the TCD studies were associated with a hematocrit of 26% or less, while 33% of the studies were associated with a hematocrit of 30% or less.
Age‐Related Changes of the Insular Cortex and Lateral Ventricles: Conventional MRI Volumetric Measures
Authors: Foundas Anne L. , Zipin Debra , Browning Cassandra A.
Published: February 2016

Preliminary data suggest that the insular region may be atrophied in patients with Alzheimer's disease when compared with healthy, age‐matched control subjects. Therefore, normative data on age‐related changes of the insular cortex were gathered and compared with age‐related changes in the bodies of the lateral ventricles, which have been studied previously Cerebrospinal fluid (CSF) volume of the lateral ventricles and insular cortical regions were measured on T1‐weighted axial magnetic resonance images in 93 healthy subjects (age, 21 to 84 years). Age‐related changes were found in the lateral ventricles (r = 0.57, p < 0.0001) and in the CSF insular space (r = 0.42, p < 0.0001). Increasing age accounted for a significant amount of the variance for the lateral ventricle (pc = 0.45, p < 0.0001), but not for the insula (pc = 0.15, p = 0.14). Although there was a continuous linear increase in lateral ventricular volume with age, the CSF insular space increased linearly until the fourth decade, then plateaued until the seventh decade, with a linear increase thereafter. These data suggest that age‐related changes occur in the region of the insular cortex, but differ from age‐related changes of the lateral ventricles.
Transcranial Doppler Sonography Guided by Magnetic Resonance Angiography for Improved Monitoring of Intracranial Arteries
Authors: Auer A. , Felber S. , Lutz W. , Kremser C. , Schmidauer C. , Hochmair E. , Aichner F.
Published: February 2016

Transcranial Doppler (TCD) sonography combines the advantages of real–time hemodynamic information, cost–effectiveness, and bedside application. However, measurements can be difficult to reproduce because the spatial resolution and the determination of insonation angles are limited. The purpose of this study was to use the high anatomic resolution of threedimensional (3D) magnetic resonance angiography (MRA) images for the stereotactic guidance of TCD in order to improve the accuracy and reproducibility of TCD examinations. The MRA examinations were performed on a 1.5 T scanner using a 3D flow compensated gradient–echo sequence. A noninvasive stereotactic mask was used for image registration. The MRA data were then transferred to a personal computer. An infrared tracking system registered the position of the head and the ultrasound probe during TCD. This enabled the authors to superimpose a virtual ultrasound beam onto the MRA projections of the intracranial arteries displayed on the monitor of the personal computer. This allows the examiner to easily identify the insonated intracranial artery and displays the insonation angle. In volunteer examinations (n=1 0), the accuracy and reproducibility
What Do Neurologists Think About Their Role in Neuroimaging Training and Practice?
Authors: Masdeu Joseph C
Published: February 2016

In 1996, a survey of the members of the American Academy of Neurology revealed the following facts and opinions: (1) On an average month, each respondent ordered 15 computed tomography, 22 magnetic resonance imaging, 13 ultrasound and 1 single‐photon emission computerized tomography studies. (2) Most respondents did not read their own studies for reimbursement, but relied on their own reading for patient management. (3) Respondents felt that neurologists are appropriate specialists to read imaging studies; however, they favored certification for neurologists credentialed in neuroimaging. (4) Organized neurology should provide certification in neuroimaging for neurologists with appropriate training and defend their right and their need to practice neuroimaging, including endovascular procedures.
Diagnostic Benefit of Echocontrast Enhancement for the Insufficient Transtemporal Bone Window
Authors: Nabavi Darius G. , Droste Dirk W. , Schulte‐Aitedorneburg Gernot , Kemèny Vendel , Panzica Martin , Weber Sepp , Ringelstein E. Bernd
Published: February 2016

Echocontrast agents (ECA) are known to improve transcranial color‐coded duplex (TCCD) imaging, but its diagnostic benefit in the routine clinical setting has not clearly been defined. The authors investigated the diagnostic benefit of ECA application in 54 patients with insufficient transtemporal bone window, consecutively referred to their ultrasound laboratory. According to the precontrast imaging quality, patients were assigned to three categories: A, no intracranial structures or vessel segments visible on B‐mode imaging and TCCD (n = 5); and intracranial structures visible on B‐mode imaging and vessel segments less than 5 mm in length (B, n = 21 ), or larger than 5 mm in length (C, n = 28) visible on TCCD. The effect of the echocontrast enhancement was assessed with respect to signal enhancement, imaging quality, and diagnostic confidence. In 49 out of 54 patients (91%), a significant improvement of the imaging quality was noted, enabling 43 (80%) neurovascular diagnoses of sufficient diagnostic confidence. The diagnostic ECA effect was strongly dependent on the precontrast imaging quality: upon echoenhancement, a satisfactory image quality was obtained in none of the patients of category A, as opposed to 16 (76%) and 27 (96%) patients of categories B and C, respectively. In summary, in 80% of our consecutive patient series with insufficient transtemporal bone window, application of ECA allowed for a conclusive TCCD study. Properties of the transtemporal precontrast scans are strongly predictive of the diagnostic benefit and should be taken into the decisive consideration.
Multimodality Monitoring During Passive Tilt and Valsalva Maneuver Under Hypercapnia
Authors: Hetzel A. , Braune S. , Guschlbauer B. , Dohms K. , Prasse A. , Lücking C.H.
Published: February 2016

In occlusive cerebrovascular disease cerebral blood flow (CBF) autoregulation can be impaired and constant CBF during fluctuations in blood pressure (BP) cannot be guaranteed. Therefore, an assessment of cerebral autoregulation should consider not only responsiveness to C02 or Diamox. Passive tilting (PT) and Valsalva maneuver (VM) are established tests for cardiovascular autoregulatory function by provoking BP changes. To develop a comprehensive test for vasomotor reactivity with a potential increase of sensitivity and specificity, the authors combined these maneuvers. Blood pressure, corrected to represent arterial pressure at the level of the circle of Willis, middle cerebral artery Doppler frequencies (DF), heart rate (HR) and endtidal partial pressure of C02 (P1CO2 ) were measured continuously and noninvasively in 81 healthy subjects (19–74 years). Passive tilt and Valsalva maneuver were performed under normocapnia (mean, 39 ‒ 4 mmHg C02) and under hypercapnia (mean, 51 ‒ 5 mm Hg C02). Resting BP, HR, and DF increased significantly under hypercapnia. Under normocapnia and hypercapnia, PT induced only minor, nonsignificant changes in mean BP at the level of the circle of Willis compared to baseline (normocapnia: ‒ 2 ‒ 15 mm Hg; hypercapnia: ‐3 ± 13 mm Hg). This corresponded with a nonsignificant decrease of the mean of DF (normocapnia: ‐4 ± 11%; hypercapnia: ‐6 ± 12%). Orthostasis reduced pulsatility of BP by a predominantly diastolic increase of BP without significant changes in pulsatility of DF. Valsalva maneuver, with its characteristic rapid changes of BP due to elevated intrathoracic pressure, showed no significant BP differences in changes to baseline between normocapnic and hypercapnic conditions. Under both conditions the decrease in BP in phase II was accompanied by significantly increased pulsatility index ratio (P1DFP1BP). Valsalva maneuver and PT as established tests in autonomic control of circulation provoked not only changes in time‐mean of BP but also in pulsatility of BP. The significant increase in pulsatility ratio and decrease of the DF/BP ratio during normocapnia and hypercapnia indicated preserved CBF autoregulation within a wide range of CO2 partial pressures. Hypercapnia did not significantly influence the autoregulatory indices during VM and PT. Physiologically submaximally dilated cerebral arterioles can guarantee unchanged dynamics of cerebral autoregulation. Combined BP and MCA‐DF assessment under hypercapnia enables investigating the effect of rapid changes of blood pressure on CO2 ‐induced predilated cerebral arterioles. Assuming no interference of hypercapniainduced vasodilation, VM, with its rapid, distinct changes in BP, seems especially to be adequate provocation for CBF autoregulation. This combined vasomotor reactivity might provide a more sensitive diagnostic tool to detect impaired cerebral autoregulation very early.
Pontine Cryptococcoma in a Nonimmunocompromised Individual: MRI Characteristics
Authors: Kesler Roman , Maertens Paul
Published: February 2016

The case of a pontine cryptococcoma in a nonimmunocompromised, previously healthy 16‐year‐old boy is presented. The patient had slowly progressive brainstem signs with right cranial nerves V, VII, and VIII palsies, and contralateral corticospinal and spinothalamic deficits. Magnetic resonance images (MRI) revealed, within the right pons, a 1‐cm diameter round mass lesion, hypointense on T1‐weighted images, hyperintense on T2‐ weighted images, and with rim enhancement after infusion of gadopentetate dimeglumine. This is the only report of the MRI findings in an isolated pontine cryptococcoma in an immunocompetent patien. Early recognition of this specific MRI pattern is essential, because complete recovery can be achieved with prompt antifungal treatment.
Doppler Pulse Waveform Analysis of Carotid and Middle Cerebral Artery Flow in a Patient With an Intra‐aortic Balloon Pump
Authors: Ober David , Kalman Jill , Weinberger Jesse
Published: February 2016

A 60‐year‐old man with intractable congestive heart failure (CHF) had an intra‐aortic balloon pump placed to augment coronary artery perfusion. During the evaluation prior to heart transplant, carotid and transcranial Doppler ultrasonography (TCD) was performed. The authors report the findings of Doppler waveform analysis and the presence of balloon pump artifact which caused difficulty in distinguishing between internal and external carotid arteries. Higher blood flow velocity during diastole and diastolic runoff characteristically seen while insonating the internal carotid artery enabled that distinction.