bluuebunny/crossref_metadata_2025 huggingface dataset:
Power Doppler Imaging and Color Doppler Flow Imaging for the Evaluation of Normal and Pathological Vertebral Arteries
Authors: Ries Stefan , Steinke Wolfgang , Devuyst Gerald , Artemis Nikos , Valikovics Attila , Hennerici Michael
Published: February 2016

Recently, an ultrasound method for vascular applications using the amplitude of the reflected echosignal for the generation of intravascular color signals has been introduced. We compared the utility of this power Doppler imaging (PDI) with conventional color Doppler flow imaging (CDFI) for examination of vertebral arteries (VA) Forty‐nine patients with signs and symptoms suggesting ischemia within the posterior circulation were evaluated. Quality of blood flow visualization by PDI and CDFI at the different VA segments was classified according to a four point scale. Furthermore, combined sonographic findings were correlated with the results of digital substraction and/or magnetic resonance angiography (DSA, MRA). Power Doppler imaging provided a significantly superior visualization of the intertransversal VA, whereas display of the intracranial V4 segment was superior 1ignificantly on CDFI. Both methods were complementary for the evaluation of the VA at the origin. With respect to the angiographic findings, combined CDFI and PDI achieved a sensitivIty of 90.63% and a specificity of 97.22% for the differentiation of healthy and pathologic VAs. Power Doppler imaging is complementary to CDFI for the sonographic assessment of VA disease. Combined use of PDI and CDFI achieves a high sensitivIty and specificity, thus increasing diagnostic confidence.
Observer Variability in the Measurement of the Size of Intracranial Aneurysms Using Power TCD
Authors: Percival Juliet , Wardlaw Joanna Marguerite , Cannon James
Published: February 2016

This study assessed the observer variability for measurement of intracranial aneurysmal size visualized on color “power” Transcranial Doppler Ultrasound (TCD). Patients with recent subarachnoid hemorrhage underwent color “power” TCD blind to angiography. Identified aneurysms were measured from the frozen image (in real time or from video tape) using the trackball function. Two observers measured the maximum (systolic) and mininum (end diastolic) area of each aneurysm, and an adjacent reference artery. Each observer was blind to the other's results. lnterobserver variability was assessed using the Bland and Altman technique. Thirty‐nine aneurysms were identified in 32 patients in 10 months. The maximum cross‐sectional area of the aneurysm was 38:41 mm2 (observer 1 :observer 2), and the mean difference was –3 mm2 (95% confidence interval [CI] of the difference – 5.4–1 .46 mm2).The maximum cross‐sectional area of the reference artery was 26:28 mm2 (observer 1 : observer 2), and the mean difference was –2 mm2 (95% Cl –5.7–1.2 mm2 ) Neither difference was significant. lntraobserver reliability also was good. The measurement of intracranial aneurysm and artery size with power TCD is reliable sufficiently for use in longitudinal studies of changes in aneurysm size.
SPECT and Lumbar MRI in Back Pain with Emphasis on Changes in End Plates in Association with Disc Degeneration
Authors: Lusins John O. , Cicoria Anthony D. , Goldsmith Stanley J.
Published: February 2016

Over a two‐year period, 48 sequential patients were selected because they showed type I or II end plate changes on magnetic resonance imaging (MRI) and/or had positive single‐photon emission computerized tomography (SPECT) scan in the area of disc degeneration. They were selected out of a large group of patients who were being evaluated by MRI and SPECT scan for low back pain. In this group of 48 patients, 47 had positive SPECT scans at the disc space, which on MRI indicates degenerative disc disease. Of these, 38 had end plate changes on the MRI, but 10 did not have end plate changes on the MRI even though their SPECT was positive. None of the 48 patients had evidence of other pathology such as fracture, metastatic disease or spondylolysis. The MRI changes were both of type I and type II and thought to represent increased vascularization of the fibrous tissue or fatty replacement of marrow in the area of the end plate. Based on this study, we are proposing that a positive end plate SPECT in degenerative disc disease is related to marrow changes in the region of the end plate of the disc. Also, we are proposing that SPECT may be of value in delineating early end plate changes prior to the MRI showing type I or type II change in the same area.
The Influence of Different Gases on Acoustic Properties of a Spherosome‐Based Ultrasound Contrast Agent (BY963)
Authors: Seidel Günter , Beller Klaus-Dieter , Aaslid Rune , Hummel Rolf-Peter , Thibaut Ulrich , Vidal-Langwasser Marion , Kukat Bernd , Kaps Manfred
Published: February 2016

Ultrasound contrast agents improve the signal‐to‐noise ratio of reflected ultrasound, enhancing the diagnostic value of transcranial Doppler (TCD). In dog studies, we investigated the time course of TCD signal amplitude after application of a phospholipid‐containing ultrasound contrast agent (BY963) filled with different gases. The median time of Doppler amplitude enhancement exceeding 5 dB was determined using isoflurane‐, isopentane‐, trichlortrifluoroethane‐, air‐, argon‐, and perfluoropentane‐filled BY963 (69, 72, 75, 78, 88, and 245 seconds respectively). The decrease of time‐intensity curve and the duration of signal enhancement showed significant differences comparing the different gases (p = 0.04 and 0.03, respectively). The time course of in vitro stability of BY963 agitated with the different gases measured by absorbance of light (500 nm) showed a retarded decay for perfluoropentane, a rapid decrease for air, isopentane, trichlortrifluoroethane, and argon, and a very rapid decrease using isoflurane. The time course of the different gases depended on the physicochemical properties (lipophilicity and the solubility in water) of the gas encoated in the phospholipid shell. Perfluoropentane‐filled BY963 showed the highest in vitro stability and the longest duration of TCD enhancement compared with the other gases used.
Calcified Cystic Lesions in a Patient with Epilepsy and Progressive Dementia
Authors: Cibula J. E. , Uthman B. M. , Strickler S. T. , Quisling R. G. , Friedman W. A. , Rojiani A. M.
Published: February 2016

A 67‐year‐old woman had intractable epilepsy and developed a progressive dementia with upper motor neuron signs over the last 6 years Magnetic resonance imaging (MRI) revealed multiple areas of large calcified cysts, which increased in number and size over the last 3 years. Discussion includes the appearance of these lesions radiologically and pathologically, as well as their differential diagnosis and clinical significance, focusing on the increasing detection of these lesions with current imaging techniques.
Duplex Criteria for Grading Internal Carotid Artery Stenosis >50% Based on Multiregression Analysis
Authors: Zbornikova Vera , Johansson Ingegerd
Published: February 2016

Different opinions exist about grading >50% stenosis resulting from differences in angiographically estimated measurements and differences in weighing hemodynamic parameters at duplex scanning. The aim of this study was to reevaluate the correlation between duplex scanning measurements and angiographic findings in >50% stenosis by using correlation coefficients instead of earlier determination coefficients in multiregression analysis in prediction of an absolute percentage of stenosis ≥50%. The authors correlated the angiographic findings for 58 vessels with 50%–99% stenosis with findings at duplex examination. Peak systolic velocity (PSV) > 1.2 m/s was the limit for >50% stenosis. The degree of stenosis was estimated as the smallest diameter of the diseased vessel divided by normal diameter of the vessel at the same level. Predictive values of different variables either alone or in combination were calculated by means of multiregression analysis. The highest predictive value was PSV, followed by late diastolic velocity (LDV) and pulse pressure (PSV − LDV) according to multiregression analysis. The results of Doppler evaluations of periorbital flow (POF) enhanced the differentiation between >75% stenosis and <75% stenosis. The combination of PSV and LDV and the result of POF coded as normal and abnormal had the highest accuracy in the prediction of absolute percentage of stenosis with a difference of 6.3 ± 4.3% (SD) between the results of duplex scanning and angiography (r = 0.88). The accuracy in discriminating instances in which there was at least 75% reduction in luminal diameter was 98.2%. We found the quotient between PSV in the internal carotid artery and PSV in the common carotid artery to be less predictive with an accuracy of 84%. However, in the presence of severe stenosis in the external carotid artery, periorbital examination is not reliable. In such a situation it is preferable to use an equation based on pulse pressure and LDV. In prediction of >75% stenosis we found multiregression analysis in the assessment of the predictive value of combined variables to be more accurate than single regression of each variable.
Clinical, Electromyographic, and Ultrasonographic Assessment of Focal Neuropathies
Authors: Schwennicke Arne , Bargfrede Meikel , Reimers Carl D.
Published: February 2016

The study was intended to evaluate the diagnostic value of muscle ultrasonography in the diagnosis of focal neuropathy. Two hundred four patients with possible unilateral injury to nerve roots, plexuses, and nerves extremity were examined prospectively by means of manual muscle testing, electromyography (EMG), and muscle ultrasonography. These findings were compared with those of 36 control subjects. Pathologic spontaneous activity correlated very closely with abnormal ultrasonographic findings, especially with increased muscular echointensity. Ultrasonography was as sensitive as manual muscle testing and EMG in the detection of muscle involvement. Ultrasonography and EMG were complementary. In about 15% of muscles, only one of the two techniques revealed pathologic findings. Increased muscle echointensity was seen in 79% and muscle atrophy in 48% of muscles assessed to be abnormal. The first ultrasonographic abnormalities appeared 10 days and pathologic spontaneous activity 18 days after acute injury. Ultrasonography was slightly but significantly less reliable than EMG. Muscle ultrasound can help in visualizing anatomic abnormalities such as muscle atrophy and mesenchymal abnormalities in nerve root, plexus, and nerve lesions.
Neurosarcoidosis Resembling Meningioma: MRI Characteristics and Pathologic Correlation
Authors: Krejchi Dan , Caldemeyer Karen S. , Vakili Saeed T. , Pritz Michael B.
Published: February 2016

A 37‐year‐old woman had visual changes. Magnetic resonance imaging showed an extraaxial mass in the anterior clinoid region that was presumed to be meningioma. There was no evidence of systemic or leptomeningeal disease. Pathologic findings were consistent with sarcoidosis. Isolated mass‐like neurosarcoidosis, without systemic or leptomeningeal disease is difficult to diagnose preoperatively.Key words: MRI, sarcoidosis, neurosarcoidosis.
Multimodal Ultrasound Versus Intraarterial Angiography for Imaging the Vertebrobasilar Circulation
Authors: Sliwka Ulrich , Rautenberg Wolfgang
Published: February 2016

The diagnostic accuracy of Doppler ultrasound examination of the vertebrobasilar system has been reported to be lower than that of examinations of the carotid system. However, with the introduction of color Doppler flow imaging, the diagnostic power in this territory may be increased. 1 Most studies have dealt with normal subjects, used color Doppler flow imaging without additional ultrasound methods, and have not used intraarterial angiography as a control. 1–3 Studies comparing a combination of the different available ultrasound systems in examinations of patients with pathologic changes in the vertebrobasilar system with intraarterial angiography have yet to be performed. Accordingly we have combined continuous‐wave Doppler, color Doppler flow, and transcranial Doppler of the vertebrobasilar territory to determine their sensitivity and specificity in comparison with intraarterial angiography in the detection of obstructive lesions.
Gadolinium‐Enhanced MR Angiography of the Carotid Arteries
Authors: Enochs W. S. , Ackerman R. H. , Kaufman J. A. , Candia M.
Published: February 2016

To assess the efficacy of gadolinium (Gd)‐enhanced magnetic resonance angiography (gdMRA) in overcoming signal dropout artifacts on conventional MRA (cMRA), the authors examined 13 patients with suspected neurovascular stenotidocclusive lesions on MRA pre‐ and post‐gadolinium enhancement The sample consisted of 18 internal carotid artery (ICA) lesions (16 extracranial, 2 cranial) In 13 of 16 stenotic vessels, gdMRA better characterized the pathoanatomy of moderate to severe stenotic lesions, changing MRA diagnosis in 3 patients. In zero of three vessels with no flow enhancement by cMRA, the lumen remained nonvisualized on gdMRA. For an ICA lesion at the skull base, enhancement of surrounding normal structures limited the usefulness of the technique. The authors conclude that Gd MRA is a fast, accurate, and convenient noninvasive technique for documenting the morphology and severity of carotid stenotic disease, especially extracranially.
Blood Flow Velocities in Three Cerebral Arteries in the Same Subjects Modulate During Thinking
Authors: Roberts Albert E. , McKinney William M.
Published: February 2016

College students (n = 22) engaged in thinking activities while simultaneous bilateral velocity (V) measures are obtained from their middle, anterior, and posterior cerebral arteries (MCA, ACA, and PCA). The study follows a 3 × 2 × 6 factorial design with repeated measures on artery insonated (MCA, ACA, and PCA), hemisphere (right and left), and six experimental phases, Nithin which an initial 62‐second baseline (BL) period is followed by five 31‐second thinking tasks (short‐term remembering, generating an image, making decisions, and solving language and math problems). VMCA is faster than BL during each thinking task (range, 4.9%‐8.5%; p < 0.001), but changes in VACA, VPCA, and all hemispheric differences are not significant. A stronger degree of increase is present for VMCA than (1) both VACA and VPCA during short‐duration remembering, making decisions, and working math problems; and (2) VACA, which in turn is stronger than VPCA when generating images and constructing new words. The authors' study shows that transcranial Doppler neuroimaging conveniently provides physiological indices of thinking from three cerebral arteries of the same subjects.
Cerebral Effects of a Single Dose of Intravenous Vinpocetine in Chronic Stroke Patients: A PET Study
Authors: Szakall Szabolcs , Boros Istvan , Balkay Laszlo , Emri Miklos , Fekete Istvan , Kerenyi Levente , Lehel Szabolcs , Marian Terez , Molnar Tamas , Varga Jozsef , Galuska Laszlo , Tron Lajos , Bereczki Daniel , Csiba Laszlo , Gulyas Balazs
Published: February 2016

The effects of vinpocetine (Cavinton) on the cerebral glucose metabolism of chronic stroke patients are studied with positron emission tomography. The regional and global cerebral metabolic rates of glucose (C MR91 u) and the kinetic constants related to them are quantified before and after single‐dose intravenous vinpocetine treatment. These measurements are completed with transcranial Doppler sonography and single photon emission computed tomography to explore the possible mechanisms underlying the resulting changes in glucose uptake and metabolism in the brain. The authors' findings indicate that a singledose vinpocetine treatment, although it does not affect significantly the regional or global metabolic rates of glucose, improves significantly the transport of glucose (both uptake and release) through the blood‐brain barrier in the whole brain, the entire contralateral hemisphere, and in the brain tissue around the infarct area of the symptomatic hemisphere. These changes are in accord with increased blood flow in the entire contralateral hemisphere as well as decreased blood flow velocity and increased peripheral vessel resistance in the entire symptomatic hemisphere.
Tortuosity of Carotid and Vertebral Arteries: A Magnetic Resonance Angiographic Study
Authors: Pelaez Jorge M. , Levine Ross L. , Hafeez Faizan , Dulli Douglas A.
Published: February 2016

Nine patients (group A) were found on magnetic resonance angiography (MRA) to have excessive carotid artery, vertebral artery, and vertebrobasilar junction tortuosity. A control group (group B) were age‐ and sex‐matched to group A patients, were selected randomly from our MRA or stroke data banks, and had not undergone MRA for evaluation of migraine, "carotidynia," or pulsatile tinnitus. Factors more prevalent in group A patients included migraine, chronic daily headache, carotidynia, pulsatile tinnitus, and a positive family history of headache. Factors more prevalent in group B pat1ents included a positive family history of stroke, large‐vessel atherosclerosis, and scan evidence of ischemic infarctions; many group B patients had undergone MRA for stroke or transient ischemic attack evaluation. Men were slightly underrepresented at 44%, and were younger than women (34 ± 6 years vs. 43 ± 3 years; p = 0.01). Relationships in this preliminary study between arterial tortuosity and migraine seem evident
Editorial
Authors: Prockop Leon D.
Published: February 2016

In this issue of JON, Joseph C. Masdeu, MD, PhD, reports upon what U.S. neurologists think about their role in neuroimaging training and practice. An equally important issue is what those entrusted with the training of neurologists think about their roles in neuroimaging training and practice.
A New Dynamic Method for Detection of Internal Jugular Valve Incompetence Using Air Contrast Ultrasonography
Authors: Ratanakorn Disya , Tesh Paul E , Tegeler Charles H
Published: February 2016

The internal jugular (IJ) valve is the only valve between the heart and the brain, preventing venous reflux into the IJ vein. Internal jugular valve competence has been tested by IJ venography, Doppler ultrasonography of the IJ vein and M‐mode ultrasonography of the IJ valve, and color flow imaging (CFI) of the IJ vein. However, interpretation of venous Doppler and CFI is difficult, and venography is invasive. The purpose of this study was to evaluate the feasibility of a new dynamic method to test IJ valve competency, and to review the literature regarding the potential clinical importance of this pathophysiology. Ten patients had intravenous injection of agitated air and saline during Valsalva maneuver with B‐mode monitoring and CFI of the right IJ vein. Contrast bubbles were clearly identified refluxing into the right IJ vein in 50% of patients. Air contrast studies more often showed IJ valve incompetence than CFI. Bubbles appeared in the IJ vein within 19.2 sec and persisted up to 282 sec. Bubble aggregation was also observed. There was no correlation between positive bubbles and the presence of spontaneous echo contrast on baseline B‐mode imaging. Air contrast ultrasound venography (ACUV) is a new noninvasive method to assess competency of the IJ valves. This technique is feasible, appears to be more sensitive than CFI, and adds a new dimension to the study of the venous system in cerebrovascular disease. Potential clinical application includes evaluation of patients with increased central venous pressure, those with morning headaches, and those on positive end‐expiratory pressure ventilators.
Diagnostic Yield of a 1‐MHz Transducer in Evaluation of the Basal Cerebral Arteries
Authors: Georgiadis D , Karatschai R , Uhlmann F , Lindner A
Published: February 2016

The authors examined the efficacy of a 1‐MHz transducer in routine ultrasound monitoring. Fifty outpatients (34 women, 16 men; mean age, 65 ± 2) with inadequate temporal bone window for examination with 2‐MHz transducers were re‐examined with a 1‐MHz transducer. Additionally, 50 controls (34 men, 16 women; mean age 49 ± 2) with adequate temporal bone window were examined with both the 1‐ and 2‐MHz transducers. Signal quality was classified as good (GQ), adequate (AQ), or poor (PQ). Finally, 30 normal controls were examined with both transducers under standardized conditions, to evaluate potential differences in velocity measurements. A total of 90 temporal windows were lacking in the 50 patients. Use of the 1‐MHz transducer resulted in identification of the middle cerebral artery in 68 cases (76%; PQ, n=13; AQ, n=29; GQ, n=26), the anterior cerebral artery in 51 cases (57%; PQ, n=23; AQ, n=17; GQ, n=11) and the posterior cerebral artery in 46 cases (51%; PQ, n=12; AQ, n=21; GQ, n=13). Examination was feasible with both transducers in the 50 controls, with minimal differences in signal quality between the two transducers. Correlation between velocity values acquired with the 1‐ and 2‐MHz transducers was significant for all vessels examined. Best values were measured for the middle cerebral artery, followed by the anterior cerebral artery and posterior cerebral artery. The authors conclude that the use of the 1‐MHz transducer increases the yield of transcranial Doppler sonography.
MRI Temporal Lobe Volume Measures and Neuropsychologic Function in Alzheimer's Disease
Authors: Smith Charles D , Malcein Monica , Meurer Kathy , Schmitt Frederick A , Markesbery William R , Creed Pettigrew L
Published: February 2016

The authors performed quantitation of the temporal lobes using magnetic resonance imaging in 20 patients with mild‐tomoderate Alzheimer's disease, 20 age‐matched aged control subjects, and 26 healthy young volunteers. Compared to young subjects, aged controls showed volume reductions in amygdala (17%, p=0.02), hippocampus (15%, p=0.0001) and temporal lobe (22%, p=0.0001). Compared to aged controls, Alzheimer's subjects showed further volume reductions in amygdala (33%, p=0.0001) and hippocampus (20%, p=0.006) but not temporal lobe (7%, p=0.15). In Alzheimer's subjects, left temporal lobe volume correlated strongly with the Mini Mental State (MMSE) score (adjusted r2 =0.46, p=0.0006) whereas right amygdala volume correlated inversely with the noncognitive ADAS score (adjusted r2=0.46, p=0.0006). The authors conclude that significant volume changes occur in the temporal lobe in aging and in Alzheimer's disease, with the greatest percentage reductions in the amygdala in Alzheimer's disease. Temporal neocortical atrophy and temporal limbic atrophy might be associated with different patterns of performance and behavior in Alzheimer's patients.
Cerebral Blood Flow Velocity During Occlusive Manipulation of Patent Ductus Arteriosus in Children
Authors: Rodriguez Rosendo A , Cornel Garry , Hosking Martin C , Weerasena Nihal , Splinter William M , Murto Kimmo
Published: February 2016

Patent ductus arteriosus (PDA) with left‐to‐right shunting modifies the Doppler flow pattern of the intracranial circulation. The ability of increases in cerebral blood flow velocity (CBFV) to predict shunt resolution during PDA occlusion was evaluated. A 2 MHz transcranial Doppler (TCD) monitored diastolic and mean CBFV, plus the systolidmean CBFV ratio in the middle cerebral artery from before (baseline) to immediately after PDA occlusion. Shunt resolution was verified by echocardiography and/or angiography. A minimum of 40% increase in diastolic‐CBFV from baseline was considered successful resolution. Patients were age‐stratified into group I (<15 months; n=23) and group II (> 15 months; n=10). Thirty‐three children were studied (age, 0.1 to 109 months) during surgical (n=22) or coil occlusions (n=11 ). Transcranial Doppler successfully identified shunt resolution in 78% of cases in group I, as compared to 0% in group II (p<0.01). Identification rate decreased from 79% in cases of minimum ductal diameter of 3 mm (n=19) to 21% in smaller ductuses (n=14) (p<0.01). Body weight and left‐atrium size (p=0.004) in group I and PDA diameter in group II (p=0.02), were the only preoperative ductal parameters associated with diastolic‐CBFV changes after ductus occlusion. Transcranial Doppler detects shunt resolution in infants with moderate to large PDAs.
Crossed Cerebellar Diaschisis: The Role of Motor and Premotor Areas in Functional Connections
Authors: Ishihara Makiko , Kumita Shin-ichiro , Mizumura Sunao , Kumazaki Tatsuo
Published: February 2016

The authors assessed the relationship between crossed cerebellar diaschisis (CCD) and cortico–pontine cerebellar pathway (CPCP) damage in 29 chronic supratentorial infarct patients to elucidate the role of motor and premotor areas for functional cerebra–cerebellar connections. The CCD rate was calculated from side–to–side cerebellar count differences on 123I–IMP singlephoton emission computerized tomography images. Neuronal damage was estimated by the three scores of computed tomography density from equal to normal brain tissue (score 0) to equal to cerebrospinal fluid (score 2) in the 4 major regions on CPCP; frontal association, motor and premotor, sensory and parietal associations, and the posterior limb of the internal capsule. Two–factor factorial ANOVA by the score and the region revealed significant differences of the CCD rate in the score factor (score 0 or 1 vs. score 2, p=<O.O5) and the independency of these two factors. Categories determined by the scores in each region were analyzed by multiple stepwise regression analysis using the theory of quantification I, in which significant correlation only between CCD and the necrotic density (score 2) in motor and premotor areas were demonstrated (r=0.515, p=<0.05). The authors conclude that neuronal loss in motor and premotor areas seem to contribute significantly to functional cerebro–cerebellar disconnections.
Neuroimaging Findings in a Patient Recovering from Global Alexia to Spelling Dyslexia
Authors: Lanzinger S , Weder B , Oettli R , Fretz C
Published: February 2016

The authors report findings in a 67‐year‐old right‐handed man who had an ischemic infarct in the territory of the left posterior cerebral artery. The clinical manifestation consisted mainly of total alexia without agraphia. The patient gradually recovered, subsequently showing the syndrome of spelling dyslexia. Cerebral MR‐images revealed a circumscript infarction of medial and basal parts of left temporal lobe. In the acute stage [99mTc]HMPAO SPECT was characterized by a diminished uptake in the definitely infarcted area and hyperfixation in the region of the left forceps major. Because high retention of HM‐PAO indicates potentially salvageable tissue after an ischemic event, the depicted area might be correlated with the recovery of function. Thus, the authors' neuroimaging data give further support to the assumption that the left forceps major is a critical area for global alexia, whereas spelling dyslexia is due to involvement of the left medio‐basal temporal lobe.
Noninvasive Assessment of the Elastance and Reserve Capacity of the Craniovertebral Contents Via Flow Velocity Measurements in the Straight Sinus by TCD During Body Tilting Test
Authors: Shakhnovich Alexander R. , Shakhnovich Victor A. , Galushkina Anna A.
Published: February 2016

Invasive recording of intracranial pressure (ICP) changes during cerebrospinal fluid (CSF) infusion‐drainage tests have been used to estimate elastance and reserve capacity of craniovertebral contents. The increase in ICP and its pulse‐related oscillations lead to “cuff constriction” of cerebral veins. The purpose of this study is noninvasive assessment of elastance and reserve capacity of craniovertebral contents (RCCC) by measurement of flow velocity (FV) in the straight sinus by transcranial Doppler (TCD) during body tilt tests, which cause changes in ICP. The study was performed in 14 healthy volunteers (age 12–49 y, 6 men) and 32 patients with Intracranial Hypertension (IH) (Benign Intracranial Hypertension, n = 14; Brain Tumors, n = 18). The straight sinus was insonated through the occipital window during body tilt tests (BTI). Tilt table position was changed gradually from head up (−75°) to head down ( −45°). It was established that systolic flow velocity and amplitude of FV pulsations (Amp) in horizontal position in patients is usually higher than in healthy volunteers. We found that reserve capacity of craniovertebral contents in patients with IH was usually exhausted. Elastance in patients was usually significantly higher than in healthy volunteers. Evaluation of cerebral venous circulation during body tilt tests clearly differs between the patients with IH and the healthy volunteers. The degree of this difference depends on the localization and character of the pathologic process.
Safety and UltrasoundEnhancing Potentials of a New Sulfur Hexafluoride‐Containing Agent in the Cerebral Circulation
Authors: Kaps Manfred , Seidel Günter , Bokor Daniela , Modrau Boris , Algermissen Christian
Published: February 2016

Insufficient ultrasound penetration through the temporal bone is a serious limitation of transcranial ultrasound diagnostics. In a phase I study, the authors studied safety and ultrasound enhancing potentials of the new transpulmonary ultrasound contrast agent SonoVue, which contains sulfur hexafluoride gas microbubbles stabilized by a phospholipid shell. Twelve healthy volunteers received four different doses of SonoVue (0.3 ml, 0.6 ml, 1.2 ml, and 2.4 ml) intravenously. The duration of ultrasound contrast enhancement was measured by transcranial Doppler sonography (TCD) and transcranial color‐coded sonography (TCCS). Safety and tolerability was monitored during the study and for 24 hours after contrast agent administration. TCD: Duration of spectral enhancement (signal intensity of 5 dB over baseline) was observed dose‐related (p<0,0001; Friedman‐test) for (0.3 ml) 136 ± 63.4 seconds; (0.6 ml) 191 ± 63.3 seconds; (1.2 ml) 314 ± 88 seconds; (2.4ml) 434 ± 168 seconds [mean ± SD]. Dependent on dosage, the peak signal amplification in TCD was significantly different (p<0.001; Friedman‐test) as well: (0.3 ml) 24.5 ± 2.0 dB; (0.6 ml) 26.0 ± 1.6 dB; (1.2 ml) 27.6 ± 2.2 dB; (2.4 ml) 28.4 ± 2.2 dB (mean ± SD). TCCS: Mean time of optimal enhancement increased from 214 ± 73 seconds (0.3 ml) to 356 ± 14 seconds (2.4 ml) in a dosedependent manner. In TCCS, signal amplification appeared to be stronger with increasing doses. Adverse events were not observed during the study. This investigation describes the ultrasound enhancing potential of SonoVue in the intracranial cerebral circulation. SonoVue proved to be well tolerated and provided a long‐lasting ultrasound contrast enhancement that supports an optimal transcranial ultrasound diagnostic.
Harmonic Grey Scale Imaging of the Human Brain
Authors: Seidel Günter , Greis Christian , Sonne Jan , Kaps Manfred
Published: February 2016

Harmonic imaging increases the signal‐to‐noise ratio in greyscale imaging. With the use of ultrasound contrast agents (UCA), imaging of brain perfusion seems possible. The authors used an ultrasound system in connection with a 1.8/3.6‐MHz harmonic sector transducer and an acoustic densitometry unit for quantification of ultrasound intensity in the thalamus (THAL), the temporoparietal white matter (TPWM), and the lateral fissure (LF). Ten milliliters of BY963, a spherosome‐air‐based UCA, was injected intravenously in 12 healthy volunteers. Timeintensity curves were calculated. Mean increase of intensity (standard deviation [SD]), mean area under the time‐intensity curve (AUC) from baseline (SD), and mean transit time (MTI) (SD) in the region of LF, THAL, and TPWM were 2.2 ± 1.7, 1.1 ± 0.6, 0.9 ± 0.9 dB and 16.7 ± 22.7, 4.7 ± 4.7, 3.7 ± 6.3 as well as 11.1 ± 3.5, 9.7 ± 3.1, and 11.9 ± 8.0, respectively. There was a statistically significant difference for mean AUC (p = 0.02) but none comparing mean intensity increase (p = 0.07) and MTI (p = 0.9). The authors' study indicates that different regions of the human brain show different time‐intensity curves. These results suggest that it is possible to measure parameters closely related to perfusion in various regions of the adult human brain.
Rhabdomyolysis Lesions Showing Magnetic Resonance Contrast Enhancement
Authors: Kakuda Wataru , Naritomi Hiroaki , Miyashita Kohtaro , Kinugawa Hidekazu
Published: February 2016

Although T2‐weighted magnetic resonance imaging (MRI) was reported to be useful for depicting rhabdomyolysis lesions, little is known as to the usefulness of gadolinium‐enhanced T1‐weighted imaging. The authors performed noncontrast and postcontrast T1‐weighted MRI along with T2‐weighted MRI in a patient with rhabdomyolysis in the chronic phase. Noncontrast T1‐weighted imaging revealed no abnormality, whereas postcontrast T1‐weighted imaging demonstrated lesions more definitively than T2‐weighted imaging. Gadolinium‐enhancement study may contribute to the MRI diagnosis of rhabdomyolysis.
Neuroacanthocytosis Masquerading as Huntington's Disease: CT/MRI Findings
Authors: Kutcher Jeffrey S. , Kahn Marc J. , Andersson Hans C. , Foundas Anne L.
Published: February 2016

Neuroacanthocytosis (NA) is a rare, degenerative, presumably autosomal‐recessive disorder of the nervous system presenting in adulthood and is associated with acanthocytosis of the peripheral blood. The clinical spectrum of NA shares similarities with Huntington's disease (HD), including dyskinetic choreiform movements and degeneration of the caudate nucleus. A woman presented with choreiform movements and was given a presumed diagnosis of HD. Neuroimaging studies were consistent with HD. She lacked the genetic marker for HD, and further evaluation revealed acanthocytosis of the peripheral blood. The case illustrates the similarities and differences in the clinical presentations and neuroimaging studies of these two disease entities, emphasizing the need for a careful clinical evaluation.
The Inferior Petrosal Sinus: Assessment by Transcranial Doppler Ultrasound Using the Suboccipital Approach
Authors: Doepp Florian , Hoffmann Olaf , Lehmann Rüdiger , Einhäupl Karl Max , Valdueza José Manuel
Published: February 2016

Recently, intracranial veins and sinuses have been successfully insonated using the transtemporal and transoccipital approaches by transcranial Doppler ultrasound. The purpose of this study was to prove the capacity of the Doppler method to evaluate the inferior petrosal sinus via the suboccipital approach. Venous transcranial ultrasound was performed with a range‐gated 2‐MHz transducer in 80 healthy volunteers and patients without central nervous system disorders ranging in age from 15–84 years (mean ± standard deviation [SDL 37.6 ± 15.2 years). A venous signal with a flow directed toward the probe was considered to originate from the inferior petrosal sinus because of its proximity to the basilar artery. The inferior petrosal sinus was insonated in 96.3% of the cases at least on one side. It was found bilaterally in 48 (60%), on the right side in 74 (92.5%), and on the left side in 51 (63.8%) subjects, respectively. Mean blood flow velocity ranged from 8–53 cm/s (mean ± SD, 19.6 ± 8.7 cm/s). A significant age dependency of venous velocities was found. Weak but significant side‐to‐side differences were observed, reflecting the known right‐sided predominance of venous outflow in humans. Using the suboccipital approach, the inferior petrosal sinus can be insonated in a high percentage of subjects without major difficulties and is defined by its vicinity to the basilar artery.
The Role of Quantitative Ictal SPECT Analysis in the Evaluation of Nonepileptic Seizures
Authors: Spanaki Marianna V , Spencer Susan S , Corsi Maria , MacMullan John , Seibyl John , George Zubal I
Published: February 2016

Nonepileptic seizures may represent difficult diagnostic problems. Identifying their presence and frequency is critical for determining appropriate treatment. The authors investigated the value of quantitative perfusion changes as measured by ictal single‐photon emission tomography (SPECT) difference images in differentiating nonepileptic from epileptic seizures. Eleven patients with a clinical suspicion of nonepileptic events had ictal and interictal technetium‐99m hexamethylpropylene amine SPECT scans during continuous audiovisual surface electroencephalogram (EEG) monitoring. The authors analyzed perfusion difference images based on registration, normalization, anci subtraction of ictal and interictal SPECT images. The difference images were registered to each patient's magnetic resonance imaging scan to anatomically localize ictal perfusion changes. Three of 11 patients also carried the diagnosis of epilepsy and were taking antiepileptic medication. Five patients were taking antiepileptic drugs, but the diagnosis of epilepsy was not confirmed. In all patients, continuous video EEG monitoring revealed no ictal EEG findings. In nine of these patients, visual interpretation of ictal SPECT was suggestive of localized increased (n = 6) or decreased perfusion (n = 3). In all patients, however, no blood flow changes were noted on quantitative SPECT analysis with injections performed during the seizure‐like event, suggesting the diagnosis of pseudoseizures. The authors' results suggest that quantitative ictal SPECT analysis is a useful tool in the diagnosis of nonepileptic seizures.
Radial Microbrain Form of Micrencephaly: Possible Association With Carbamazepine
Authors: Hashimoto Laura Nickles , Thomas Bass W , Green Glen A , Werner Alice L , Reagan Thomas J
Published: February 2016

A premature infant exposed to carbamazepine in utero had a markedly undersized brain on cranial ultrasonogram. Postmortem examination of the brain revealed no evidence of hypoxic‐ischemic injury, hemorrhage, infarction, congenital infection, or calcification. The normal cortical gyral pattern, normal residual germinal matrix, and normal cortical lamination suggested the diagnosis of a radial microbrain form of micrencephaly.
Intracranial Clot Dissolution Is Associated With Embolic Signals on Transcranial Doppler
Authors: Alexandrov Andrei V. , Demchuk Andrew M. , Felberg Robert A. , Grotta James C. , Krieger Derk W.
Published: February 2016

Reperfusion of intracranial arteries can be detected by transcranial Doppler (TCD). The authors report microembolic signals (MES) on TCD as a sign of clot dissolution and recanalization. Microembolic signals were detected during routine diagnostic TCD examination performed in the emergency room in patients eligible for thrombolytic therapy. Microembolic signals were found at the site of M1 middle cerebral artery (MCA) highgrade stenosis or near‐occlusion. Transcranial Doppler was performed before, during, and after thrombolytic therapy. Of 16 consecutive patients, 3 (19%) had MES on TCD. All three patients had a severe MCA syndrome at 2 hours after stroke onset scored using the National Institutes of Health Stroke Scale (NIHSS). In patient #1 (NIHSS 12), clusters of MES were detected distal to a high‐grade M1 MCA stenosis preceding spontaneous clinical recovery by 2 minutes. Because of subsequent fluctuating clinical deficit, intraarterial thrombolysis was given with complete recovery. In patient #2 (NIHSS 20), TCD detected an M1 MCA near‐occlusion. At 1.5 hours after intravenous tissue plasminogen activator, TCD showed minimal MCA flow signals followed by MES, increased velocities, and normal flow signals in just 2 minutes. She gradually recovered up to NIHSS 8 in 5 days. In patient #3 with NIHSS 22 and an M1 MCA near‐occlusion, TCD detected MES 15 minutes after TPA bolus followed by MCA flow velocity improvement from 15 em/sec to 30 em/sec. The patient recovered completely by the end of tissue plasminogen activator infusion. The authors conclude that embolic signals detected by TCD at the site of arterial obstruction can indicate clot dissolution. Intracranial recanalization on TCD can be associated with MES and changes in flow waveform, pulsatility, and velocity if insonation is performed at the site of arterial obstruction.
Caffeine Can Affect Velocity in the Middle Cerebral Artery During Hyperventilation, Hypoventilation, and Thinking: A Transcranial Doppler Study
Authors: Perod Anne L. , Roberts Albert E. , McKinney William M.
Published: February 2016

This study examined possible caffeine‐mediated changes in blood flow velocity in the middle cerebral artery (VMCA) induced by tests of cerebrovascular responsiveness. Transcranial Doppler (TCD) sonography provided simultaneous bilateral VMCA measures while healthy college students hypoventilated, hyperventilated, and performed cognitive activities (short‐term remembering, generating an autobiographical image, solving problems), each in 31‐second tests. VMCA measures were obtained from the same persons, in separate testing sessions, when they were noncaffeinated and under two levels of caffeine: a smaller amount (from a cola, 45 mg/12 oz) and a larger amount (from coffee, 117 mg/8 oz). Compared with the no‐caffeine control condition, a smaller amount of caffeine had no significant effects on global VMCA, but a larger amount suppressed VMCA by 5.8%. Time‐course analyses showed that VMCA (1) followed a triphasic pattern to increase over baselines during hypoventilation regardless of caffeine condition, (2) slowed below baselines during hyperventilation (with the degree of slowing attenuated under caffeine), and (3) increased over baselines during all cognitive activities (ranges 3.8‐6.9%). It is concluded that a large amount of caffeine can suppress VMCA, and this possibility should be anticipated when TCD is used to assess cerebral hemovelocity.
Magnetization Transfer Ratio of the Spinal Cord in Multiple Sclerosis: Relationship to Atrophy and Neurologic Disability
Authors: Lycklama à Nijeholt Geert J , Castelijns Jonas A , Lazeron Richard H. C. , van Waesberghe Jan Hein T. M. , Polman Chris H , Uitdehaag Bernard M. J. , Barkhof Frederik
Published: February 2016

The authors compare the spinal cord magnetization transfer ratio (MTR) of multiple sclerosis (MS) patients to healthy volunteers, relate MTR to spinal cord atrophy, and relate these and other magnetic resonance (MR) imaging parameters to disability. Sixty‐five patients with MS (14 relapsing remitting [RR] 34 secondary progressive [SP] and 17 primary progressive [PP] MS), and 9 healthy volunteers were studied using MR at 1.0 T. Disability of the patients was assessed using the expanded disability status scale (EDSS). Magnetic resonance parameters were upper spinal cord MTR, number of focal spinal lesions, presence of diffuse abnormalities, and spinal cord cross‐sectional area (CSA). Correlations were assessed using Spearman's rank correlation coefficient (r). Magnetization transfer ratio was higher in the controls (median, 33% range, 30%‐38%) than in patients with MS (median, 30%; range, 16‐36; p < 0.05). In patients with MS, EDSS correlated with spinal cord MTR, albeit weakly (r = ‐0.25, p < 0.05). Correlation between EDSS and spinal cord CSA was better (SRCC = ‐0.40, p < 0.01 ). No correlation was found between MTR and CSA (r = 0.1, p = 0.4). Combining MTR with spinal cord CSA improved correlation with EDSS (r = ‐0.46, p < 0.001 ), suggesting an independent correlation between disability and these 2 MR parameters. Expanded disability status scale scores were higher in patients who had diffuse spinal cord abnormality regardless of focal lesions (median, 6; range, 1.5–7.5) than in patients without diffuse abnormalities (median, 3.5; range, 0–8; p < 0.01). CSA was lower in patients with diffuse spinal cord abnormality (median, 62; range, 46–89 mm2) than in patients without diffuse abnormalities (median, 73; range, 47–89 mm2; p < 0.01). MTR was slightly lower in patients with diffuse spinal cord abnormalities (median, 29; range, 21%–33%) than in patients without diffuse abnormalities (median, 31; range, 16–36; t–test, p < 0.05).
Utility of Magnetic Resonance Imaging in Acute Intracerebral Hemorrhage
Authors: Dylewski Drew A , Demchuk Andrew M , Morgenstern Lewis B
Published: February 2016

The authors determine whether magnetic resonance imaging (MRI) during acute hospitalization for spontaneous intracerebral hemorrhage (ICH) provides new diagnostic information. ICD‐9 codes were used to identify consecutive patients with spontaneous ICH at Hermann Hospital, Houston, Texas, between January 1995 and August 1997. Two investigators employed rigorous criteria to determine whether the MRI findings led to a specific new diagnosis. Two hundred ninety‐one patients met inclusion and exclusion criteria. Sixty‐seven (23%) patients underwent brain MRI during the acute hospitalization. MRI provided a new diagnosis in 15 of these 67 patients (22%). Amyloid angiopathy and vascular malformation (four each) were the most frequently identified etiologies. The yield of MRI was low in basal ganglia and thalamic hemorrhage. Two of 23 (9%) patients with deep ICH and 13 of 44 (30%) patients with lobar and infratentorial hemorrhage had etiology determined by MRI. Timing of MRI did not affect yield.
Cerebrovascular Findings in Takayasu Disease
Authors: Hoffmann Michael , Corr Peter , Robbs John
Published: February 2016

The authors define the frequency, nature, and extent of cerebrovascular sequelae of Takayasu arteritis using functional imaging. Retrospective analysis of the cases derived from the Durban Stroke Data Bank (n = 11 00) and Durban Metropolitan Vascular Surgery Database (n = 5300) consisted of evaluation by contemporary neuroimaging modalities including single positron emission computed tomograpy (SPECT), magnetic resonance imaging (MRI) diffusion scanning, and transcranial Doppler (TCD). Of all the patients identified with Takayasu disease (n = 142), 29 (20%) patients were identified with a primarily cerebrovascular presentation. The recent advent of modern functional imaging techniques allowed only the 10 most recent patients with a cerebrovascular presentation to be evaluated. Of these 10, 8 (80%) had normal neurologic deficit scores (Canadian neurologic score) and 9 (90%) were not disabled as determined by handicap scores (Rankin). The anatomic brain scans (9 MRI, 1 CT) were normal in 5 patients (50%). In 7 patients, transcranial Doppler sonography revealed increased velocities mainly in the anterior circulation with turbulence that was not circumscribed. Single positron emission computed tomograpy scanning revealed areas of hypoperfusion, mostly multiple, in all of the 7 cases investigated. The cerebral perfusion index was determined in 7 patients, with a good prognosis in 2 patients and a moderate prognosis in 5. Cerebral effects of Takayasu disease are best monitored by a combination of clinical and functional imaging such as TCD and SPECT scanning.
Spinal Cord MRI Hyperintensities in Cervical Spondylosis: An Ischemic Pathogenesis?
Authors: Mifsud Victoria , Pullicino Patrick
Published: February 2016

The pathophysiology of focal spinal cord MRI T2 hyperintensity (SCHI) in patients with cervical spondylosis is uncertain. This study was undertaken to determine the frequency and cause of SCHI. The authors reviewed serial cervical spine magnetic resonance imaging (MRI) reports and reviewed scans with spondylosis and cord compression or SCHI. The authors noted the location, shape, and extent of SCHI, and severity of spondylosis (expressed as a spondylosis score [SS]). The authors recorded the age and vascular risk factors for each patient. Nineteen of 273 scans (7%) with cervical spondylosis and 19 of 36 scans (53%) with cord compression had SCHI. The SCHI extended for one vertebral level from the compression in 12 patients and for three vertebral levels in 5 patients, and were distant from the compression in 2 patients. The SCHI had a focal, symmetrical, anterior spinal artery terminal zone location in 16 of 19 scans (84%). A rim isointense with normal cord separated all SCHI from the pial surface. Patients with SCHI were older (58.3 years ± 12.8 years versus 46.8 ± 8.1 years) (p = 0.007) and had a higher SS (5.7 ± 2.4 versus 3.9 ± 1.4) (p = 0.02) than patients without SCHI. The SCHI relates to the severity of cervical spondylosis. The anterior spinal artery territory location, the normal cord between SCHI and the compressive lesion, and the presence of SCHI at a distance from the compressive level all suggest an ischemic basis for SCHI.