bluuebunny/crossref_metadata_2025 huggingface dataset:
Decreasing the dispatch time of medical reports sent from hospital to primary care with Lean Six Sigma
Authors: Basta Yara L. , Zwetsloot Inez M. , Klinkenbijl Jean H.G. , Rohof Thomas , Monster Mathijs M.C. , Fockens Paul , Tytgat Kristien M.A.J.
Published: February 2016

Rationale, aims and objectives

Timely communication is important to ensure high‐quality health care. To facilitate this, the Gastro Intestinal Oncology Center Amsterdam (GIOCA) stipulated to dispatch medical reports on the day of the patient's visit. However, with the increasing number of patients, administrative processes at GIOCA were under pressure, and this standard was not met for the majority of patients. The aim and objective of this study was to dispatch 90% of medical reports on the day of the patient's visit by improving the logistic process.

Methods

To assess the main causes for a prolonged dispatch time and to design improvements actions, the roadmap offered by Lean Six Sigma (LSS) was used, consisting of five phases: Define, Measure, Analyze, Improve and Control (DMAIC roadmap).

Results

Initially, 12.3% of the reports were dispatched on the day of the patient's visit. Three causes for a prolonged dispatch time were identified: (1) determining which doctors involved with treatment would compose the report; (2) the reports composed by a senior resident had to be reviewed by a medical specialist; and (3) a medical specialist had to authorize the administration to dispatch the reports. To circumvent these causes, a digital form was implemented in the electronic medical record that could be completed during the multidisciplinary team meeting. After implementation, 90.6% of the reports were dispatched on the day of the visit.

Conclusion

The dispatch time of reports sent from hospital to primary care can be significantly reduced using Lean Six Sigma, improving the communication between hospital and primary care.
Life Cycle Assessment of Offshore Wind Farm Siting: Effects of Locational Factors, Lake Depth, and Distance from Shore
Authors: Tsai Liang , Kelly Jarod C. , Simon Brett S. , Chalat Rachel M. , Keoleian Gregory A.
Published: February 2016

According to previous studies, the life cycle energy intensity of an offshore wind farm (OWF) varies between 0.03 and 0.13 megawatt‐hours (MWh) of primary energy for each MWh of electricity generated. The variation in these life cycle energy intensity studies, after normalizing for capacity factor and life span, is significantly affected by OWF location because of geographical properties, namely, wind speed and water depth. To improve OWF siting, this study investigates how an OWF's distance from shore and geographical location impacts its environmental benefit. A process‐based life cycle assessment is conducted to compare 20 OWF siting scenarios in Michigan's Great Lakes for their cumulative fossil energy demand, global warming potential, and acidification potential. Each scenario (four lake locations at five offshore distances) has unique foundation, transmission, installation, and operational requirements based on site characteristics. The results demonstrate that the cumulative environmental burden from an OWF is most significantly affected by (1) water depth, (2) distance from shore, and (3) distance to power grid, in descending order of importance, if all other site‐relevant variables are held constant. The results also show that when OWFs are sited further offshore, the benefit of increased wind energy generation does not necessarily outweigh the increase in negative environmental impacts. This suggests that siting OWF nearer to shore may result in a better life cycle environmental performance. Finally, we demonstrate how much an OWF's environmental burdens can be reduced if the OWF system is either recycled, transported a shorter distance, or manufactured in a region with a high degree of renewable energy on the grid.
Micro‐CT scouting for transmission electron microscopy of human tissue specimens
Authors: MORALES A.G. , STEMPINSKI E.S. , XIAO X. , PATEL A. , PANNA A. , OLIVIER K.N. , MCSHANE P.J. , ROBINSON C. , GEORGE A.J. , DONAHUE D.R. , CHEN P. , WEN H.
Published: February 2016

Transmission electron microscopy (TEM) provides sub‐nanometre‐scale details in volumetric samples. Samples such as pathology tissue specimens are often stained with a metal element to enhance contrast, which makes them opaque to optical microscopes. As a result, it can be a lengthy procedure to find the region of interest inside a sample through sectioning. We describe micro‐CT scouting for TEM that allows noninvasive identification of regions of interest within a block sample to guide the sectioning step. In a tissue pathology study, a bench‐top micro‐CT scanner with 10 μm resolution was used to determine the location of patches of the mucous membrane in osmium‐stained human nasal scraping samples. Once the regions of interest were located, the sample block was sectioned to expose that location, followed by ultra‐thin sectioning and TEM to inspect the internal structure of the cilia of the membrane epithelial cells with nanometre resolution. This method substantially reduced the time and labour of the search process from typically 20 sections for light microscopy to three sections with no added sample preparation.
Comparative anatomy of the extraocular muscles in four Myliobatoidei rays (Batoidea, Myliobatiformes)
Authors: Cunha Carlo M. , Oliveira Luciano E. , Kfoury Jr José R.
Published: February 2016

Extraocular muscles are classically grouped as four rectus and two oblique muscles. However, their description and potential associations with species behavior are limited. The objective was to characterize extraocular muscles in four Myliobatoidei rays from diverse habitats with divergent behaviors. Heads (10 per species) of Dasyatis hypostigma, Gymnura altavela, Mobula thurstoni and Pteroplatytrygon violacea were decalcified and dissected to characterize and describe extraocular muscles. Principal component analysis (PCA) was used to evaluate relationships between muscle length and species; for P. violacea, D. hypostigma and G. altavela, these were qualitatively and quantitatively consistent with the general pattern of extraocular muscles in vertebrates. In contrast, for M. thurstoni, the two oblique muscles were completely fused and there was a seventh extraocular muscle, named m. lateral rectus β (both were apparently novel findings in this species). There were also significant differences in eye disposition in the chondrocranium. The PCA axis 1 (rectus muscles) and PCA axis 2 (oblique muscles) accounted for 98.47% of data variability. Extraocular muscles had significant differences in length and important anatomical differences among sampled species that facilitated grouping species according to their life history. In conclusion, extraocular muscles are not uniform in all vertebrate species, thereby providing another basis for comparative studies.
Editorial Statement
Authors: Prockop Leon D.
Published: February 2016

In the Republic, Plato recorded the Socratic cave allegory. Truth Seekers find themselves deep in a dark cave. Behind a barrier that obscures the truth from direct observation, a fire casts the truth's shadowy image on an irregular cave wall. Images help define the truth of nervous system disease. Their quality beguiles physicians to accept them as truth. The Editor and Editorial Board will be guided by the philosophy that neuroimages, however precise and sophisticated, are only images, but they reflect the truth a physician seeks about a patient's disease.
Validity and Reliability of an Ultrasound Device for Detecting Carotid Emboli
Authors: Stump David A. , Stein Carl S. , Tegeler Charles H. , Hitchings Lloyd P. , Hager Richard , Eicke Martin , Burke Gregory L.
Published: February 2016

Cardioembolic mechanisms cause 15 to 20% of all strokes and may account for the high incidence of neurological dysfunction associated with cardiopulmonary bypass. Accurate identification of high‐risk subjects and/or surgical techniques would allow more effective testing and implementation of preventive or therapeutic measures to help reduce morbidity and mortality. This article reports on validity and reliability testing of a new emboli detection device that allows continuous monitoring of the common carotid artery. The instrument appears to be capable of detecting accurately particles of 193 1–1 or less in diameter and is highly reliable both within and between observers. In preliminary clinical use, the instrument also detected embolic signals in all patients monitored during cardiopulmonary bypass, while none were detected in healthy control subjects. These results establish the validity and reliability of a new emboli detection device and suggest its potential application to emboli detection monitoring during cardiopulmonary bypass.
The Use of Surface Coils for Magnetic Resonance‐guided lnterventional Procedures
Authors: Duckwiler Gary , Jabour Bradley , Wilson Charles , Levesque Michel , Lufkin Robert
Published: February 2016

The advantages of surface coils for magnetic resonance imaging (MRI) of superficial structures include improvement in signal and decreased noise. There is now a growing use ofMRI to guide interventional procedures [1–4]. Because of the geometry of needles and other interventional devices, which extend outside the patient, optimal head receiver coils often cannot be used for imaging and the lower signal‐to‐noise body coil must be used because of its large size.
Functional Studies of the Human Brain Using High‐speed Magnetic Resonance Imaging
Authors: Belliveau John W. , Cohen Mark S. , Weisskoff Robert M. , Buchbinder Bradley R. , Rosen Bruce R.
Published: February 2016

Dramatic technical advances in magnetic resonance imaging (MRI or NMR) scanning speed and recent governmental approval for the routine use of NMR contrast agents have yielded techniques for quantitative imaging of cerebral hemodynamics. The technical basis of ultrafast imaging, the methodology of dynamic imaging with contrast agents, and results in normal subjects and patients are presented.
Transcranial Doppler Findings in Acute Spontaneous Recanalization of Middle Cerebral Artery Embolism
Authors: Gomez Camllo R. , Burger Stephen K. , Smith Robert R. , Powers Alexandros , Graeber Michael
Published: February 2016

Three patients suspected of having acute middle cerebral artery occlusion were studied using transcranial Doppler sonography on admission and again during the following week. Initially, sonographic criteria for acute middle cerebral artery occlusion were present in all 3; however, follow‐up studies revealed normal Doppler waveforms and blood flow velocities. Subacute recanalization of the occlusion has been previously studied with transcranial Doppler sonography and shown to have a characteristic temporal profile evolving over weeks. Acute recanalization, in contrast, is characterized by normalization of the affected vessel's sonographic pattern within days of initial occlusion.
A 47‐Year‐Old Man with Ophthalmoplegia and Dementia
Authors: Gilden Donald H. , Kleinschmidt-DeMasters Bette K.
Published: February 2016

A 47‐year‐old man developed a rare, progressive, fatal nervous system disorder of 18 months' duration characterized by ophthalmoplegia, dementia, and hypersomnia. The imaging studies not only corroborated the anatomical site of involvement suggested by the clinical features, but were also characteristic for this rare disease. Dr Donald Gilden discusses the differential diagnosis and Dr Bette Kleinschmidt‐DeMasters describes the pathological lesions.
Lateralization of Epileptic Foci by Magnetic Resonance Imaging in Temporal Lobe Epilepsy; Reliability and Diagnostic Criteria
Authors: Kuzniecky Ruben , Gaudier Jose , Suggs Stephen , Faught Edward
Published: February 2016

A retrospective single‐blind study was carried out to assess the reliability of magnetic resonance imaging (MRI) for determining lateralization of the electrographic focus in 45 patients with in tractable temporal lobe epilepsy. With strictly defined MRI diagnostic criteria, the electroencephalographic (EEG) focus was correctly lateralized in 86% of patients. Excluding patients with structural lesions, the criteria provided for correct lateralization of the epileptogenic focus in 78% and false lateralization in 5%. Hippocampal atrophy on T1‐weighted images and increased signal intensity from mesial structures on T2‐weighted scans were highly reliable for lateralization. Postoperative outcome did not differ between the patients with normal and those with abnormal findings on MRI, but the group sample was inadequate to assess the issue of surgical outcome. These findings suggest that with appropriate techniques and strictly defined diagnostic criteria, MRI can provide reliable seizure lateralization in patients with intractable temporal lobe epilepsy.
High‐Resolution B‐Mode Ultrasound Reading Methods in the Atherosclerosis Risk in Communities (ARIC) Cohort
Authors: Riley Ward A. , Barnes Ralph W. , Bond M. Gene , Evans Greg , Chambless Lloyd E. , Heiss Gerardo
Published: February 2016

To measure the association of cardiovascular disease risk factors with carotid artery diameter and thickness of the intima and media in the general population, standardized ultrasound scanning and reading protocols were performed on 15,800 individuals in the multicenter Atherosclerosis Risk in Communities (ARIC) Study. In a randomly selected subset of 855 participants, the mean artery diameter, minimum lumen diameter, and maximum near‐and far‐wall thicknesses were measured at a core laboratory from B‐mode image recordings of the common carotid, bifurcation, and internal carotid arteries to determine both within‐reader and between‐reader variability. Measurements associated with the wall thickness are sensitive indicators of reader reproducibility, with between‐reader reliability coefficients ranging from 0. 78 to 0.93 and coefficients of variation ranging from 13.1 to 18.3%. The percent of paired readings in the three carotid segments for which the absolute difference of the far‐wall thickness measured by different readers was no greater than one image pixel (0.067 mm) was 58% (common carotid), 53% (internal carotid), and 42% (bifurcation). Highly reproducible measurements of carotid artery dimensions can be achieved with standardized training and performance of ultrasound scanning and reading protocols.
Forces and Torques Produced by a 640‐Gauss Permanent Magnet on Ferromagnetic Objects
Authors: Sheldon Philip , Carlson Joseph , Kaufman Leon
Published: February 2016

Magnetic forces and torques were measured in a 640‐G permanent magnet The forces on external objects were directed in such a way and of such a strength that the likelihood of injury from unsupported ferromagnetic objects was very small. The forces and torques on ferromagnetic objects within the subject were comparable to those produced by gravitational and inertial efforts in daily living.
The Effects of Dolichoectasia on Transcranial Doppler Measurements
Authors: Babikian Viken , Pochay Val E. , Sloan Michael A. , Burdette David
Published: February 2016

Transcranial Doppler sonography is used to evaluate intracranial hemodynamic changes associated with cervical and intracranial arterial lesions; however, studies of patients with cerebral ischemia and nonstenotic lesions are uncommon. This report presents the transcranial Doppler findings in 4 patients with cerebral arterial dolichoectasia demonstrated by angiography and brain computed tomography. Although blood flow velocities were decreased in all the arteries tested, the pulsatility and resistance indices were normal. Our results suggest that in patients with ischemic cerebrovascular disease, transcranial Doppler findings of low flow velocities should prompt consideration of dolichoectasia.
Takayasu's Arteritis and Multiple Sclerosis
Authors: Brashear Allison , Pascuzzi Robert M.
Published: February 2016

A 19‐year‐old woman developed symptoms, signs, and radiographic evidence of Takayasu's arteritis. She subsequently presented with fluctuating, multifocal, central nervous system deficits; abnormal magnetic resonance findings of the head and spine; and spinal fluid irregularities indicative of multiple sclerosis. These two disorders of presumed autoimmune etiology have not previously been found in the same patient, suggesting an immunopathogenic link between them.
Herniated Lumbar Disc: Change in Level over a 1‐Year Period
Authors: Goldberg Andrew L. , Deeb Ziad L. , Rothfus William E.
Published: February 2016

Sequential computed tomographic and magnetic resonance examinations in a patient with chronic lumbar radiculopathy documented change in the level of disc herniation over a 15‐month period. Whether due to migration of a single disc fragment or to regression and reherniation, this phenomenon demonstrates the need for temporal proximity of imaging evaluation and surgical intervention.
Visually Evoked Cerebral Blood Flow Responses
Authors: Sitzer Matthias , Diehl Rolf R. , Hennerici Michael
Published: February 2016

Visual stimulation of the occipital cortex results in an increased cerebral blood flow velocity (CBFV) in the posterior cerebral artery, as measured by transcranial Doppler in 10 normal subjects. The increase was greater for visual stimuli with a higher degree of complexity than for stimuli with a lower degree of complexity (movie with 30.1% maximal amplitude, checkerboard with 21%, and diffuse light with 16.3%). Endexpiratory carbon dioxide pressures (PCO2) influenced the visual‐induced changes of CBFV: Hypercapnia induced a reduction of maximal response amplitude from 30% (normocapnia) to 15% (mild hypercapnia) or 8% (severe hypercapnia) as did hypocapnia (19.6%), indicating a nonlinear interaction between the vasomotor effects of PCO2 and physiological activation. Ischemic lesions of the visual cortex studied in 7 patients also strongly reduced the CBFV responses evoked on the affected side, depending on the degree of infarcted tissue.
An Evaluation of Intravenous Xenon 133 Clearance Measured by Gamma Counters During lnterictal Cerebral Blood Flow for Epilepsy Surgery
Authors: Dasheiff Richard M. , Jumao-as Asela
Published: February 2016

Fifty‐four consecutive adult patients who enrolled in an epilepsy surgery program were prospectively studied to evaluate the utility of cerebral blood flow (CBF) for identifying the site of the epileptic focus. Tracer was injected intravenously during the interictal state, and CBF was estimated by the clearance of xenon 133 (133Xe) using a two‐compartment analysis. Extracranial monitoring of gamma radiation was performed by 32 collimated detectors placed over the head. Every patient subsequently had depth electrodes implanted into mesial temporal and mesial frontal regions bilaterally. Two patients also had occipital electrodes implanted, and 1 patient also had parietal electrodes implanted. Seizures were recorded from all patients using these depth electrodes and a closed‐circuit television monitor. A total of 79 ictal foci were identified. CBF 133Xe as determined by clearance was concordant in 20 foci (true‐positive rate of 25%), with 59 false‐negative (75%) and 25 false‐positive results. The overall sensitivity of this CBF study (compared to ictal depth electroencephalography) was 0.25, and the specificity was 0.82. It was concluded that present 133Xe CBF techniques are inadequate to identify an epileptic focus during the interictal state in adult patients.
Cavernous Angiomas: Magnetic Resonance Imaging, Transcranial Doppler, and Angiographic Correlates
Authors: Gomez Camilo R. , Gomez Sandra M. , Rosenfeld William E. , Selhorst John B.
Published: February 2016

Cavernous angiomas are congenital cerebral vascular anomalies that may be incidentally found in certain individuals. They can be responsible for cerebrovascular events and often have to be differentiated from small tumors and arteriovenous malformations. Until recently, the diagnosis of cavernous angiomas has been difficult because they cannot be imaged by cerebral angiography and they have a nonspecific appearance on computed tomography. We report 6 patients with cavernous angiomas and review their assessment using magnetic resonance imaging, which provided positive diagnostic information, and transcranial Doppler ultrasound studies, which were normal.
Magnetic Resonance Angiographic Study of Vertebral‐Basilar Flow Voids
Authors: Verro Piero , Korosec Frank R. , Turski Patrick A. , Mistretta Charles A. , Partington Curtis A. , Partington Curtis A.
Published: February 2016

In an effort to study the “no flow” void phenomenon as seen on conventional T2‐weighted (TE 80/TR 2500) magnetic resonance spin‐echo images (MRI), 30 vascular patients were studied with both MRI and magnetic resonance phase contrast angiography (MRA). Of the patients with vertebral‐basilar insufficiency, 9 (60%) of 15 had normal‐appearing flow voids in the vertebral and basilar arteries and 6 (40%) of 15 had “no flow” voids. Two of these 6 had either slow flow or normalappearing vertebral‐basilar arteries on MRA while 4 of these 6 had a positive correlation between “no flow” void and arterial occlusion. In the patients with vertebral‐basilar stroke, 3 (20%) of 15 had normal‐appearing flow voids and 12 (80%) of 15 had “no flow” voids. Two of these 12 had either slow flow or normal arteries on MRA while 10 of these 12 had a positive correlation between “no flow” void and arterial occlusion. Eleven of 30 had intraarterial studies and for 9 (82%) of the 11 there was excellent correlation with MRA findings. Fisher exact tests found significant relationships between flow voids and arterial patency in vertebral‐basilar insufficiency (p = 0.01) and in vertebral‐basilar stroke (p = 0.002). That is, MRA was able to delineate patent from slow‐flow or small‐caliber arteries from large‐vessel occlusion in patients with vertebral‐basilar insufficiency or stroke.
Serial Computed Tomography in Professional Boxers
Authors: Jordan Barry D. , Jahre Caren , Hauser W. Allen , Zimmerman Robert D. , Peterson Margaret
Published: February 2016

Forty‐five licensed professional boxers underwent serial computed tomography (CT). The average duration between the initial and last follow‐up scan was 31.3 months (range, 1 5–48 mo). Six (13%) had evidence of progressive brain injury between the first and last scan. Three boxers exhibited progressive atrophy and three developed a cavum septum pellucidum. Boxers with progressive CT changes tended to have had more fights (mean, 24.2) and more losses (mean, 7.3) than those without progressive changes (16.0 fights and 3. 7 losses) at the time of the last scan. Compared to boxers without progressive changes on CT, boxers with progressive changes had twice the frequency of losses and losses secondary to technical knockout or knockout during the time period between scans. Progressive changes on serial CT were associated with having more than ten losses (p < 0.05). These findings suggest that boxers with more than ten losses undergo a detailed evaluation.
Transcranial Doppler Monitoring of Middle Cerebral Artery Blood Flow Velocities During Three Memory Tasks
Authors: Dell Dianne M. O , Roberts A. E. , McKinney William M.
Published: February 2016

Bilateral transcranial Doppler ultrasound measures of blood flow velocities in the middle cerebral artery of college students were taken during three 90‐second memory tasks: generating and maintaining images, remembering letters, and answering general knowledge questions. Blood flow velocities in the middle cerebral artery during each task increased significantly over their respective 30‐second baseline period. Differences in blood flow velocities due to the kind of memory task, the middle cerebral artery sampled (right or left), or subject gender were not significant.
Two‐Gradient‐Echo, TwoDimensional, Fourier Transform Multisection Imaging: Comparison with Spin‐Echo Imaging
Authors: Kramer David M. , Li Andrew , Kaufman Leon , Hake Kristen
Published: February 2016

A multisection, two‐dimensional, Fourier transform, doublegradient‐ echo magnetic resonance imaging sequence with partial flip‐angle excitation and section doubling by radiofrequency encoding approximately doubles the signal‐to‐noise ratio obtainable from a conventional spin‐echo sequence at low field strength, while maintaining essentially equivalent contrast.
Magnetic Resonance Angiography in the Evaluation of Dural Carotid‐Cavernous Fistulas
Authors: Standaert David G. , Galetta Steven L. , Hurst Robert W. , Chawluk John B.
Published: February 2016

The diagnosis of dural carotid‐cavernous fistula is often elusive. The 2 patients described experienced the insidious onset of ocular signs and symptoms. Evaluation over several months including computed tomography and magnetic resonance imaging revealed only nonspecific abnormalities. In both patients, magnetic resonance angiography showed features characteristic of carotid‐cavernous shunting, confirmed by cerebral arteriography. Magnetic resonance angiography is an important tool for the evaluation of patients with suspected dural carotidcavernous fistulas.
CT and MRI Demonstrate Midbrain Hemorrhage in Acute Wernicke's Encephalopathy
Authors: Motgi Guru , Campbell William W.
Published: February 2016

Wernicke's encephalopathy is a common but underrecognized condition occurring primarily but not solely in alcoholics. In an alcoholic patient with acute panophthalmoplegia and intermittent retraction nystagmus, computed tomography demonstrated gross midbrain hemorrhage initially mistaken for atypical hypertensive bleeding. Magnetic resonance imaging revealed periaqueductal hemorrhage and edema. The cerebrospinal fluid was xanthochromic. Substantial resolution of the ophthalmoplegia followed intravenous administration of thiamine. In appropriate clinical circumstances, “hypertensive” hemorrhage in the midbrain should arouse the suspicion of Wernicke's encephalopathy.
Detection of Vasospasm Complicating Lobar Hematoma by Transcranial Doppler Sonography
Authors: Sloan Michael A. , Rigamonti Daniele , Kittner Steve J.
Published: February 2016

Although symptomatic vasospasm complicating aneurysmal subarachnoid hemorrhage is well known, vasospasm rarely follows nonaneurysmal subarachnoid hemorrhage. This reports a patient who suffered delayed neurological deterioration following a parietal lobe hemorrhage that extended into the subarachnoid space. Transcranial Doppler findings were consistent with middle cerebral artery vasospasm, which was confirmed by angiography.
Magnetic Resonance Imaging in the Diagnosis of Vertebral Artery Dissection
Authors: Walz Elizabeth T.
Published: February 2016

Vertebral artery dissection is an uncommon disorder but should be considered in those who present with posterior fossa ischemia. Until recently the diagnosis required four‐vessel angiography. In this case, magnetic resonance imaging with gadolinium established the diagnosis.
Reversible Central Pontine Abnormalities
Authors: Estol Conrado J. , Caplan Louis R.
Published: February 2016

Two patients developed central pontine signal changes on magnetic resonance imaging (MRI), one after heart transplantation and one during the puerperium. In one, no lesion was found in the pons at necropsy. The other recovered clinically and the MRI lesion resolved completely. These cases raise the possibility that rapid electrolyte and biochemical perturbations can give rise to transient edema in the central pons. If more severe or chronic, the edema may cause permanent myelin damage, so‐called myelinolysis.
Magnetic Resonance Angiography in Vertebrobasilar Ischemia; Preliminary Experience
Authors: Verro Piero , Levine Ross L. , Turski Patrick A. , Partington Curtis
Published: February 2016

Forty‐five patients were evaluated for vertebrobasilar ischemic disease by magnetic resonance imaging and magnetic resonance angiography (MRA). Ten also underwent intraarterial digital subtraction angiography. All were sorted into three groups based on results of the MRA and their clinical presentation. In the first group, vertebrobasilar ischemic ,disease could be reasonably excluded. In the second, such disease was nearly certain. In the third group, the vertebrobasilar system could not readily be assessed by MRA alone and often required further studies. In 8 of 10 patients a strong correlation was found between MRA and intraarterial digital subtraction angiography. MRA provided valuable information for assessing vertebrobasilar disease and, in many instances, eliminated the need for invasive angiography.
Obituary
Authors: Greenberg Jack O
Published: February 2016

“Bill's mind was Einstein's universe, finite, but boundless. Always reaching into spheres you wouldn't imagine.” These are the words of L. Jolyon West, MD, Chairman of Psychiatry at UCLA. Bill died from the complications of heart disease on December 14, 1992. The scientific community has been well aware of his prodigious research and fundamental observations in blood‐brain barrier mechanisms, cerebral metabolism, and perhaps most importantly, the principles of computed tomography.
Cognitive Disturbances and Magnetic Resonance Imaging Findings in Multiple Sclerosis
Authors: Boné Gertraud , Ladurner Gunther , Dinkhauser Lienhart , Mader Ingrid
Published: February 2016

Twenty patients (mean age ± standard deviation, 42 ± 14 yr) with multiple sclerosis were studied to define a possible relation between cognitive decline and pathology seen on magnetic resonance images (MRis). In all, a battery of psychometric tests and MRis were conducted. MRI results were classified according to cerebral lesions and different ventricle indexes. A rating scale graded the severity of cerebral lesions. MRI and psychometric data from the patients were compared with the results of an age‐ and sex‐matched control group. The results suggest that evidence of cognitive decline shows a stronger relation to substance loss, defined by ventricle indexes, than to the lesion score.
Magnetic Resonance Imaging in Empty Sella Phenomena
Authors: Gouliamos A. D. , Athanassopoulou A. K. , Souvatzoglou A. M. , Kalovidouris A. E. , Vlahos L. J. , Papavasiliou C. G.
Published: February 2016

Of 500 consecutive unselected patients who underwent brain magnetic resonance imaging (MRI), 20 (12 females, 8 males; mean age, 41 yr) were found to have empty sella. The clinical and imaging findings were compared to those in 20 normal adult control subjects, and 20 patients of comparable age and sex from the group of 500 consecutive patients. Variations in the pituitary infundibulum, the optic chiasm, and the sellar floor did not correlate to symptoms. Little difference in clinical symptomatology between patients with empty sella and control subjects was found. It is concluded that empty sella is often an insignificant finding in adults.
Computed Tomography Analysis of Head and Spinal Cord Injuries Inflicted by Missiles and Explosives
Authors: Kalousek Miljenko , Hat Josip , Krolo Ivan , Marotti Miljenko , Lupret Velimir , Smiljanic Danko
Published: February 2016

Cerebral and spinal column computed tomography (CT) was performed in 53 patients wounded during war in the Republic of Croatia from June through December 1992. Of these, 36 (67%) suffered craniocerebral injuries; 10 (18%) sustained facial, neck, and paranasal sinus wounds; and 7 (13%) had vertebral andjor paravertebral lesions. Twenty‐five (70%) of the patients with craniocerebral injuries had penetrating wounds with diffuse and multiple, predominantly hemorrhagic lesions of cortical and subcortical structures, with basal ganglia lesions in 15 (43%) and brainstem lesions in 6 (20%). Of the 7 vertebral studies. 4 showed paravertebral tissue damage to the spinal column and cord.
"Idiopathic" Trochlear Nerve Paresis Revisited with Gadolinium Diethylenediaminepentaacetic Acid
Authors: Ellenberger Carl , Cantore William A.
Published: February 2016

Magnetic resonance imaging (MRI) with gadolinium diethylenediaminepentaacetic acid (Gd‐DTPA) detected a small enhancing lesion along the tentorial course of the fourth cranial nerve in each of 2 patients who had diplopia for longer than 6 months caused by paresis of the superior oblique muscle. Because of the small size and inaccessibility of the tumors, histopathological diagnosis has not been made. The appearance of similar lesions along other cranial nerves in previously reported patients, particularly the eighth nerve, and the discovery of similar lesions in patients with neurofibromatosis, argue that these lesions in the 2 patients are most likely nerve sheath tumors, the smallest yet detected by clinical diagnostic methods. To identify this and other causes of "idiopathic" cranial neuropathy, it is recommended that Gd‐DTPA‐enhanced MRI be part of a thorough evaluation of patients with chronic cranial neuropathy causing diplopia.
The Moving Embolus
Authors: Caplan Louis R. , Allam Gregory J. , Teal Phillip A.
Published: February 2016

A young woman had sudden onset of a left hemiparesis. Initial studies showed a right internal carotid artery (ICA) thrombus and reduced flow in the right middle cerebral artery (MCA). The next day, the right ICA and MCA were widely patent but thrombi were present in MCA branches. Echocardiography and transcranial Doppler studies later showed a patent foramen ovale, with passage of air bubbles through the atrial septum into the MCA. Thromboembolism is a dynamic process. Segmental ultrasound studies can document and follow the passage of emboli.
BB Shots Within the Sella Turcica
Authors: Root Allen W. , Smith Donald A. , Pavan Peter R.
Published: February 2016

A 12‐year‐old girl was struck by two rapidly fired BB shots that penetrated the ethmoid and sphenoid sinuses and lodged within the sella turcica. Small preretinal, subretinal, and inferior vitreous hemorrhages developed in the left eye, but no neurological abnormalities were detected. Managed conservatively, the ocular hemorrhages resolved. Three years after the injury, the patient had no significant ophthalmological, neurological, or endocrinological abnormalities.
Carotid Plaques and Multiple Brain Infarctions
Authors: Micieli G. , Bosone D. , Cavallini A. , Bono G. , Uggetti C. , Rossi F. , Nappi G.
Published: February 2016

Cerebral ischemic lesions sometimes are clinically characterized by major cognitive impairment such as vascular dementia. Among the quantifiable factors able to cause focal and/or diffuse ischemic lesions, carotid atherothrombotic plaques represent possible "foci" of embolism that lead to cortical and/or subcortical infarcts. The aim of the present study was to investigate the qualitative and quantitative aspects of carotid plaques in a group of patients affected by vascular dementia and a group of patients affected by multiple brain infarctions, in order to verify whether significant differences can be detected. These data point out the importance of plaque composition and morphology in the pathogenesis of brain infarction leading to dementia.
Transcranial Doppler Validation Pilot Study
Authors: Babikian Viken , Sloan Michael A. , Tegeler Charles H. , DeWitt L. Dana , Fayad Pierre B. , Feldmann Edward , Gomez Camilo R.
Published: February 2016

The use of transcranial Doppler sonography (TCD) for the evaluation of patients with ischemic cerebrovascular disease remains controversial. This study was organized to gather preliminary data regarding the sensitivity and specificity of TCD when compared to cerebral angiography in detecting stenosing lesions and collateral flow patterns of the anterior cerebral circulation. Forty‐two patients from six medical centers were prospectively enrolled. Each received cerebral angiography and TCD testing within 24 hours of each other. Based on TCD criteria established a priori, the results were first analyzed by a blinded investigator and then by computer. Computerized analyses were then repeated with modified criteria. Collateral flow through the anterior communicating and ophthalmic arteries was detected with sensitivities of 62% and 100%, and specificities of 98% and 92%, respectively. Internal carotid artery proximal and distal severe (> 70%) stenoses were detected with sensitivities of 79% and 1 00% and specificities of 88% and 97%. Middle and anterior cerebral artery stenoses and middle cerebral artery occlusion were detected with specificities exceeding 98%; however, the data were insufficient to determine sensitivity. Computerized analyses did not permit improvement of sensitivity and specificity of the baseline criteria. The selected TCD criteria are highly specific in detecting intracranial stenoses and collateral flow patterns of the anterior circulation. The criteria have limited but acceptable sensitivity and specifity in detecting internal carotid artery origin severe stenoses, and are highly sensitive in detecting ophthalmic artery retrograde flow. A study with a larger sample is necessary to provide definitive guidelines for diagnosis.
Magnetic Resonance Angiography in Glomus Arteriovenous Malformation of the Cervical Spine
Authors: Polachini Ilydio , Kanaan Azzam S. , Dagli Rajesh D. , Koymen Nalm , Magalhaes Alvaro
Published: February 2016

Conventional magnetic resonance imaging (MRI) and spine magnetic resonance angiography (MRA) demonstrated a glomus‐type intradural arteriovenous malformation of the upper cervical region of the spine in a 24‐year‐old woman. Gadolinium‐enhanced, three‐dimensional, phase‐contrast angiography displayed the nidus and feeders of the arteriovenous malformation. The clinical features of the two most common types of spinal arteriovenous malformations (dural arteriovenous fistula and glomus intradural arteriovenous malformation) are reviewed. Conventional MRI and spine MRA may obviate the need for performing total spinal myelography in patients suspected of having spinal arteriovenous malformations.
Multiple Sclerosis Associated with Cerebral Mass Lesions on Computed Tomography
Authors: Zuheir AI-Kawi M. , Siqueira Edir B. , Haider Abdulrazzaq
Published: February 2016

Two patients with multiple sclerosis presenting as a rapidly progressive intracerebral mass lesion are described. Both showed irregular ring enhancement on computed tomography. Brain biopsy specimens showed features of acute demyelination and intense glial reaction. Treatment with oral corticosteroids was followed by clinical improvement.
Comparison of Glucose Metabolism and Cerebral Blood Flow During Cortical Motor Activation
Authors: Hallett Mark , Dubinsky Richard M , Zeffiro Thomas , Bierner Samuel M
Published: February 2016

Regions of cerebral cortex activated in normal subjects making simple, repetitive, voluntary wrist movements were studied with positron emission tomography (PET). The regional cerebral metabolic rate of glucose utilization was studied with 2‐[18F]fluoro‐2‐deoxy‐D‐glucose (FDG), and regional cerebral blood flow was studied with 15O‐labeled water. No significant activation was found with the cerebral metabolic rate studies. Studies of regional cerebral blood flow showed significant activation of the contralateral sensorimotor cortex region of 42%, of the ipsilateral sensorimotor cortex region of 19%, and of the medial frontal cortex of 30% compared with the resting state. Increases in blood flow in the contralateral sensorimotor cortex and medial frontal cortex were visible on every activated scan. Measurement of regional cerebral blood flow seems to be more sensitive than regional cerebral metabolic rate of glucose utilization for studying cortical activation with voluntary movement.
In Vivo Proton Spectroscopy of Intracranial Infections and Neoplasms
Authors: Yamagata Nelson T , Miller Bruce L , McBride Duncan , Chang Linda , Chiang Francis , Nikas Diana , Osborne Diane , Buchthal Steven D
Published: February 2016

The chemical characteristics of 10 neoplastic and 11 infectious brain masses were studied by in vivo 1H magnetic resonance spectroscopy. In tumors, peak height ratios of n‐acetyl‐L‐aspartate to choline were decreased compared to those in normal brain tissue and infectious masses (p < 0.02), but the ratios in normal brains and those with infections did not differ. N‐acetyl‐L‐aspartate—to‐creatine/phosphocreatine ratios were significantly lower in infectious masses and tumors compared to normal brain tissue (p = 0.003). However, in progressive multifocal leukoencephalopathy, N‐acetyl‐L‐aspartate appeared relatively unchanged. Lactate was greater than choline in 9 of 11 brains with infection, 0 of 14 control brains, and 1 of 10 tumors. Lactate‐to‐choline ratios were significantly elevated in infectious masses compared with tumors (p < 0.01). 1H magnetic resonance spectroscopy is promising for the noninvasive diagnosis of focal brain masses.
Recurrent Syncope and Quadriplegia
Authors: Yu Carlos M , Gomez Camilo R , Manepalli Anantha , Faber Joana A , Levy Beth
Published: February 2016

A 72‐year‐old man had posturally induced syncopal episodes, followed by quadriparesis, coma, and death. Neuroimaging studies supported the clinical diagnosis confirmed by neuropathological findings.
Superior Sagittal Sinus Thrombosis in the Presence of Idiopathic Bilateral Internal Jugular Vein Stenosis
Authors: Saponaro Stephen A , Flanders Adam E , Friedman David P , Mandel Steven
Published: February 2016

Cerebral venous outflow obstruction and anomalies in cerebral venous circulation predispose to dural sinus thrombosis. This case report illustrates the magnetic resonance and angiographic findings in a patient who had superior sagittal sinus thrombosis secondary to idiopathic bilateral internal jugular vein stenosis, a previously unrecognized entity. The findings suggest that bilateral stenosis of the internal jugular veins at their junction with the innominate veins causes obstruction to cerebral venous outflow leading to dural sinus thrombosis.
Speech Fluency in Aphasia: Regional Cerebral Blood Flow Correlates of Recovery Using Single‐Photon Emission Computed Tomography
Authors: Mlcoch Anthony G , Bushnell David L , Gupta Sudha , Milo Thomas J
Published: February 2016

This study investigated the relationship between diminished regional cerebral blood flow (rCBF) and the recovery of fluent speech in aphasia. Single‐photon emission computed tomographic brain scans using [123I]N‐isopropyl‐p‐iodoamphetamine were obtained from 14 nonfluent aphasic patients within 30 days of cerebral infarction. Measurements of speech fluency were acquired initially and at 3 months after infarction. Nearly all of the patients exhibited significant hypoperfusion to combinations of the anterior and posterior regions of the basal ganglion, the periventricular white matter, and the inferior frontal regions. Only the inferior frontal area was significantly associated with recovery of fluent speech. This region was hypoperfused in 4 of 5 patients with poor recovery while 8 of the 9 patients with good speech fluency recovery demonstrated normal rCBF to the inferior frontal region.
Marchiafava‐Bignami Disease
Authors: Marjama Jill , Yoshino Mark T , Reese Charles
Published: February 2016

Marchiafava‐Bignami disease is a rare demyelinating disease involving the corpus callosum and other central white matter tracts. In the patient described here, the disease produced extensive demyelination of the corpus callosum and deep cerebral white matter. This widespread demyelination, confirmed pathologically, was associated with a fulminant fatal course. The magnetic resonance imaging appearance is quite suggestive of Marchiafava‐Bignami disease and plays an important role in the premortem diagnosis.
Cystic Cervical Intramedullary Ependymoma with Previous lntracyst Hemorrhage: Magnetic Resonance Imaging at 1.5 T
Authors: Sweasey T. A. , Brunberg J. A. , McKeever P. E. , Sandler H. M. , Chandler W. F.
Published: February 2016

A patient with a cystic cervical ependymoma is described. Magnetic resonance imaging identified evidence of previous intratumor hemorrhage, which was confirmed at surgery. The images, operative findings, and pathology are reviewed.
Parinaud's Syndrome as the Initial Manifestation of Acquired Immunodeficiency Syndrome
Authors: Griffin Denise K , Shriver Mary Ellen , Hauser Robert
Published: February 2016

The initial manifestation of human immunodeficiency virus infection is highly variable. This reports Parinaud's syndrome as the initial manifestation of acquired immunodeficiency syndrome.
Subacute Sclerosing Panencephalitis: Imaging and Clinical Correlation
Authors: Bohlega S , Al‐Kawi M. Z.
Published: February 2016

Twenty‐one patients at different clinical stages of subacute sclerosing panencephalitis were studied by magnetic resonance imaging and computed tomography. In patients in the early clinical stage, the imaging studies appeared normal. Within 6 months, diffuse or focal areas of high signal on T2‐weighted magnetic resonance images were evident. Progressive hemispheric, cerebellar, and brainstem atrophy was seen later. Lesions of the deep nuclei were noted frequently in patients in the early and intermediate stages, with the lentiform involved more than the caudate. Magnetic resonance imaging was better than computed tomography in illustrating white matter and basal ganglia abnormalities. Radiographic progression occurred regardless of clinical course.
A Comparison of Quantitative Electroencephalography, Computed Tomography, and Behavioral Evaluations to Localize Impairment in Patients with Stroke and Transient Ischemic Attacks
Authors: Nuwer Marc R , Árnadóttir Gudrún , Martin Neil A , Ahn Samuel S , Carlson Linda G
Published: February 2016

Brain computed tomography and a structured behavioral assessment provided a better correlation than did quantitative electroencephalography to the presence of mild stroke or transient ischemic attacks in 21 patients. When electroencephalography did not correlate well, it tended to localize too laterally or miss deep lesions. Computed tomography did not identify 2 lesions when done early after disease onset. No test was uniformly more sensitive or accurate than others. They may complement each other.
Brainstem Toxoplasmosis in Patients with Acquired Immunodeficiency Syndrome
Authors: Daras Michael , Koppel Barbara S , Samkoff Lawrence , Marc Joseph
Published: February 2016

Brainstem involvement by Toxoplasma gondii is probably more common than other opportunistic infections, although it has not received adequate attention. Identification of toxoplasmosis is essential, as this condition responds to treatment with a significant increase in life expectancy. During the past 4 years, 366 AIDS patients with central nervous system toxoplasmosis diagnosed by biopsy or improvement following empirical treatment were evaluated. Among them, 8 (7 men, 1 woman; aged 25‐55 yr) presented with signs of brainstem dysfunction. Six patients presented with an oculomotor nerve palsy and contralateral hemiplegia; 1 had an additional ipsilateral rubral tremor. The seventh patient had complete external ophthalmoplegia and the eighth had Parinaud's syndrome. Computed tomography revealed enhancing lesions in the brainstem of all patients. Seven responded to treatment with pyrimethamine and sulfadiazine.
Evolution of Crossed Cerebellar Diaschisis in Middle Cerebral Artery Infarction
Authors: Miura Hiroyuki , Nagata Ken , Hirata Yutaka , Satoh Yuichi , Watahiki Yasuhito , Hatazawa Jun
Published: February 2016

To elucidate the evolution of crossed cerebellar diaschisis, cerebral oxygen metabolism was measured repeatedly by positron emission tomography (PET) in 35 consecutive patients with unilateral cerebral infarction within the territory of middle cerebral artery. The crossed cerebellar diaschisis was defined as significant when the laterality ratio of cerebral oxygen metabolism between the left and right cerebellar hemispheres exceeded the control range (mean ± 2 standard deviations) as derived from 27 age‐matched normal volunteers. Significant crossed cerebellar diaschisis was observed in 31 patients (89%) on the initial PET studies. Of these 31 patients, 23 with infarcts involving the frontal sensorimotor cortex persistently had crossed cerebellar diaschisis up to 5 years after onset, whereas the diaschisis disappeared in 8 patients with smaller infarcts mainly in the frontal or parietal lobe without recovery of oxygen metabolism in the infarcted areas. These present results suggest that crossed cerebellar diaschisis can exist persistently even in the late stage in those having a lesion involving the cortical pontine‐cerebellar pathways.