341 results on '"L. Benes"'
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152. Poland's Politics: Idealism vs. Realism
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Vaclav L. Benes and Adam Bromke
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General Materials Science - Published
- 1968
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153. The Second Soviet-Yugoslav Dispute. Full Text of Main Documents April-June 1958, with an Introductory Analysis
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Janko N. Jankovic, Vaclav L. Benes, Robert F. Brynes, and Nicholas Spulber
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Linguistics and Language ,Computer science ,Library science ,Language and Linguistics - Published
- 1960
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154. The Soviet Yugoslav Controversy, 1948-58: A Documentary Record
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Milorad M. Drachkovitch, Robert Bass, Elizabeth Marbury, Vaclav L. Benes, Robert F. Byrnes, and Nicolas Spulber
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Literature ,business.industry ,Political science ,General Medicine ,Ancient history ,business - Published
- 1961
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155. History of Modern Slovakia
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Vaclav L. Benes and Jozef Lettrich
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General Medicine - Published
- 1957
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156. The Machinability of Different Albromet W130 Plates Thicknesses by WEDM to the Required Surface Roughness Value.
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Mouralova K, Benes L, Zahradnicek R, Fries J, and Manova A
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Wire Electrical Discharge Machining (WEDM) technology represents an unconventional but vital manufacturing technology in many different industrial branches. The automotive industry and its many significant requirements bring the need to manufacture inserts and mould segments for plastic injections from Albromet W130 material, with a required roughness, Ra, from 4.5 to 5 µm so that subsequent profile etching can be eliminated. A planned experiment of 60 rounds was carried out to discover the optimal machining parameters, namely, the pulse-off time, gap voltage, discharge current, pulse-on time, and wire speed in order for the thickness of 10 to 100 mm (after 10 mm) to demonstrate the required roughness. The goal was to evaluate the surface roughness, maximise the cutting speed, and manufacture it without surface or subsurface defects. The evaluation of the planned experiment led to the establishment of optimised WEDM machining parameters with which thicknesses of 10-100 mm will always be produced with the required roughness, Ra, from 4.5 to 5 µm and with the highest possible cutting speed. It was also proven that the machining does not lead to surface or subsurface defects, and thus, the service life of the manufactured parts will not be affected. more...
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- 2024
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157. Frontotemporal disorders: the expansive panoply of syndromes and spectrum of etiologies.
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Hoffmann M, Rossi F, Benes Lima L, and King C
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Background: Frontotemporal lobe disorders (FTD) are amongst the most common brain neurodegenerative disorders. Their relatively covert, frequently subtle presentations and diverse etiologies, pose major challenges in diagnosis and treatments. Recent studies have yielded insights that the etiology in the majority are due to environmental and sporadic causes, rather than genetic in origin., Aims: To retrospectively examine the cognitive and behavioral impairments in the veteran population to garner the range of differing syndrome presentations and etiological subcategories with a specific focus on frontotemporal lobe disorders., Methodology: The design is a retrospective, observational registry, case series with the collection of epidemiological, clinical, cognitive, laboratory and radiological data on people with cognitive and behavioral disorders. Inclusion criteria for entry were veterans evaluated exclusively at Orlando VA Healthcare System, neurology section, receiving a diagnosis of FTD by standard criteria, during the observation period dated from July 2016 to March 2021. Frontotemporal disorders (FTD) were delineated into five clinical 5 subtypes. Demographic, cardiovascular risk factors, cognitive, behavioral neurological, neuroimaging data and presumed etiological categories, were collected for those with a diagnosis of frontotemporal disorder., Results: Of the 200 patients with FTD, further cognitive, behavioral neurological evaluation with standardized, metric testing was possible in 105 patients. Analysis of the etiological groups revealed significantly different younger age of the traumatic brain injury (TBI) and Gulf War Illness (GWI) veterans who also had higher Montreal Cognitive Assessment (MOCA) scores. The TBI group also had significantly more abnormalities of hypometabolism, noted on the PET brain scans. Behavioral neurological testing was notable for the findings that once a frontotemporal disorder had been diagnosed, the four different etiological groups consistently had abnormal FRSBE scores for the 3 principal frontal presentations of (i) abulia/apathy, (ii) disinhibition, and (iii) executive dysfunction as well as abnormal Frontal Behavioral Inventory (FBI) scores with no significant difference amongst the etiological groups. The most common sub-syndromes associated with frontotemporal syndromes were the Geschwind-Gastaut syndrome (GGS), Klüver-Bucy syndrome (KBS), involuntary emotional expression disorder (IEED), cerebellar cognitive affective syndrome (CCA), traumatic encephalopathy syndrome (TES) and prosopagnosia. Comparisons with the three principal frontal lobe syndrome clusters (abulia, disinhibition, executive dysfunction) revealed a significant association with abnormal disinhibition FRSBE T-scores with the GGS. The regression analysis supported the potential contribution of disinhibition behavior that related to this complex, relatively common behavioral syndrome in this series. The less common subsyndromes in particular, were notable, as they constituted the initial overriding, presenting symptoms and syndromes characterized into 16 separate conditions., Conclusion: By deconstructing FTD into the multiple sub-syndromes and differing etiologies, this study may provide foundational insights, enabling a more targeted precision medicine approach for future studies, both in treating the sub-syndromes as well as the underlying etiological process., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Hoffmann, Rossi, Benes Lima and King.) more...
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- 2024
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158. Mathematical Models for Machining Optimization of Ampcoloy 35 with Different Thicknesses Using WEDM to Improve the Surface Properties of Mold Parts.
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Mouralova K, Bednar J, Benes L, Prokes T, Zahradnicek R, and Fries J
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Wire electrical discharge machining (WEDM) is an unconventional machining technology that can be used to machine materials with minimum electrical conductivity. The technology is often employed in the automotive industry, as it makes it possible to produce mold parts of complex shapes. Copper alloys are commonly used as electrodes for their high thermal conductivity. The subject of this study was creating mathematical models for the machining optimization of Ampcoloy 35 with different thicknesses (ranging from 5 to 160 mm with a step of 5 mm) using WEDM to improve the surface properties of the mold parts. The Box-Behnken type experiment was used with a total of 448 samples produced. The following machining parameters were altered over the course of the experiment: the pulse on and off time, discharge current, and material thickness. The cutting speed was measured, and the topography of the machined surfaces in the center and at the margins of the samples was analyzed. The morphology and subsurface layer were also studied. What makes this study unique is the large number of the tested thicknesses, ranging from 5 to 160 mm with a step of 5 mm. The contribution of this study to the automotive industry and plastic injection mold production is, therefore, significant. The regression models for the cutting speed and surface topography allow for efficient defect-free machining of Ampcoloy 35 of 5-160 mm thicknesses, both on the surface and in the subsurface layer. more...
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- 2022
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159. Economic Evaluation: A Randomized Pragmatic Trial of a Primary Care-based Cognitive Behavioral Intervention for Adults Receiving Long-term Opioids for Chronic Pain.
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Smith DH, O'Keeffe-Rosetti M, Leo MC, Mayhew M, Benes L, Bonifay A, Deyo RA, Elder CR, Keefe FJ, McMullen C, Owen-Smith A, Trinacty CM, Vollmer WM, and DeBar L
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- Adult, Analgesics, Opioid therapeutic use, Cognition, Cost-Benefit Analysis, Humans, Primary Health Care, Quality of Life, Quality-Adjusted Life Years, Chronic Pain drug therapy, Cognitive Behavioral Therapy
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Background: Chronic pain is prevalent and costly; cost-effective nonpharmacological approaches that reduce pain and improve patient functioning are needed., Objective: Report the incremental cost-effectiveness ratio (ICER), compared with usual care, of cognitive behavioral therapy aimed at improving functioning and pain among patients with chronic pain on long-term opioid treatment., Design: Economic evaluation conducted alongside a pragmatic cluster randomized trial., Subjects: Adults with chronic pain on long-term opioid treatment (N=814)., Intervention: A cognitive behavioral therapy intervention teaching pain self-management skills in 12 weekly, 90-minute groups delivered by an interdisciplinary team (behaviorists, nurses) with additional support from physical therapists, and pharmacists., Outcome Measures: Cost per quality adjusted life year (QALY) gained, and cost per additional responder (≥30% improvement on standard scale assessment of Pain, Enjoyment, General Activity, and Sleep). Costs were estimated as-delivered, and replication., Results: Per patient intervention replication costs were $2145 ($2574 as-delivered). Those costs were completely offset by lower medical care costs; inclusive of the intervention, total medical care over follow-up was $1841 lower for intervention patients. Intervention group patients also had greater QALY and responder gains than did controls. Supplemental analyses using pain-related medical care costs revealed ICERs of $35,000, and $53,000 per QALY (for replication, and as-delivered intervention costs, respectively); the ICER when excluding patients with outlier follow-up costs was $106,000., Limitations: Limited to 1-year follow-up; identification of pain-related utilization potentially incomplete., Conclusion: The intervention was the optimal choice at commonly accepted levels of willingness-to-pay for QALY gains; this finding was robust to sensitivity analyses., Competing Interests: R.A.D. reports royalties from UpToDate for authoring topics on low back pain. The remaining authors declare no conflict of interest., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.) more...
- Published
- 2022
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160. Production of precision slots in copper foil using micro EDM.
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Mouralova K, Bednar J, Benes L, Plichta T, Prokes T, and Fries J
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Electrical discharge machining (EDM) is an unconventional machining technology. It allows machining of at least at least electrically conductive materials. The trend of miniaturization of industrial products is obvious. However, the required quality and accuracy must be maintained, which can be achieved with micro-EDM. One of the industrial products is also optical devices used for testing cars. These contain miniaturized parts, which are, however, necessary for their proper functioning. For this reason, this study was performed, which focused on the production of a precise slot measuring 5000 × 170 µm in a copper foil with a thickness of 125 µm. The same copper foil was used as a tool, which represents an advance in the production of micro-parts.The use of the same semi-product for the production of the slit as well as the tool itself has not yet been presented in any similar study. A design of experiment Box and Behnken Response Surface Design was performed for a total of 15 rounds, monitoring the effect of machine setting parameters (Pulse current, Pulse on time and Voltage) on responses in the form of Erosion rate, corner radius, slot length and width. Using multi-criteria optimization, the optimal setting of the machine parameters for the production of a given slit was determined, which is Pulse current = 2.1 A, Pulse on time = 40 µs and Voltage = 238.8 V. Micro-EDM technology has been found to be suitable for the production of miniaturized slits., (© 2022. The Author(s).) more...
- Published
- 2022
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161. A Primary Care-Based Cognitive Behavioral Therapy Intervention for Long-Term Opioid Users With Chronic Pain : A Randomized Pragmatic Trial.
- Author
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DeBar L, Mayhew M, Benes L, Bonifay A, Deyo RA, Elder CR, Keefe FJ, Leo MC, McMullen C, Owen-Smith A, Smith DH, Trinacty CM, and Vollmer WM
- Subjects
- Adult, Aged, Female, Humans, Male, Middle Aged, Pain Measurement, Self-Management, Analgesics, Opioid therapeutic use, Chronic Pain drug therapy, Cognitive Behavioral Therapy, Opioid-Related Disorders psychology, Opioid-Related Disorders therapy, Primary Health Care
- Abstract
Background: Chronic pain is common, disabling, and costly. Few clinical trials have examined cognitive behavioral therapy (CBT) interventions embedded in primary care settings to improve chronic pain among those receiving long-term opioid therapy., Objective: To determine the effectiveness of a group-based CBT intervention for chronic pain., Design: Pragmatic, cluster randomized controlled trial. (ClinicalTrials.gov: NCT02113592)., Setting: Kaiser Permanente health care systems in Georgia, Hawaii, and the Northwest., Participants: Adults (aged ≥18 years) with mixed chronic pain conditions receiving long-term opioid therapy., Intervention: A CBT intervention teaching pain self-management skills in 12 weekly, 90-minute groups delivered by an interdisciplinary team (behaviorist, nurse, physical therapist, and pharmacist) versus usual care., Measurements: Self-reported pain impact (primary outcome, as measured by the PEGS scale [pain intensity and interference with enjoyment of life, general activity, and sleep]) was assessed quarterly over 12 months. Pain-related disability, satisfaction with care, and opioid and benzodiazepine use based on electronic health care data were secondary outcomes., Results: A total of 850 patients participated, representing 106 clusters of primary care providers (mean age, 60.3 years; 67.4% women); 816 (96.0%) completed follow-up assessments. Intervention patients sustained larger reductions on all self-reported outcomes from baseline to 12-month follow-up; the change in PEGS score was -0.434 point (95% CI, -0.690 to -0.178 point) for pain impact, and the change in pain-related disability was -0.060 point (CI, -0.084 to -0.035 point). At 6 months, intervention patients reported higher satisfaction with primary care (difference, 0.230 point [CI, 0.053 to 0.406 point]) and pain services (difference, 0.336 point [CI, 0.129 to 0.543 point]). Benzodiazepine use decreased more in the intervention group (absolute risk difference, -0.055 [CI, -0.099 to -0.011]), but opioid use did not differ significantly between groups., Limitation: The inclusion of only patients with insurance in large integrated health care systems limited generalizability, and the clinical effect of change in scores is unclear., Conclusion: Primary care-based CBT, using frontline clinicians, produced modest but sustained reductions in measures of pain and pain-related disability compared with usual care but did not reduce use of opioid medication., Primary Funding Source: National Institutes of Health. more...
- Published
- 2022
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162. Housing instability is associated with failure to achieve virologic control among pregnant individuals with HIV.
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Cassimatis IR, Miller ES, Benes L, Levesque J, and Yee LM
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- Adult, Female, Housing, Humans, Infant, Newborn, Pregnancy, Retrospective Studies, Viral Load, HIV Infections drug therapy, Infectious Disease Transmission, Vertical
- Abstract
Background: Homelessness and housing instability, which are on the rise nationally, are considered important social determinants of health. Among nonpregnant adults living with HIV, both have been associated with decreased linkage to medical care and virologic nonsuppression. This association may be particularly concerning in pregnancy, because virologic control is the primary determinant of HIV perinatal transmission. In addition, housing instability in pregnancy may be an independent risk factor for adverse perinatal outcomes, further amplifying perinatal risks in pregnant individuals living with HIV. However, the role of housing as a social determinant of health among such individuals is largely unstudied., Objective: The objective was to examine the association between housing instability and virologic control among pregnant individuals living with HIV., Study Design: This was a retrospective cohort study of pregnant individuals seeking perinatal care in a specialty HIV clinic from 2007 to 2018. Markers of virologic control, including time from antiretroviral therapy initiation to virologic suppression, antiretroviral therapy adherence, and viral load at 36 weeks and at delivery, were assessed. All patients underwent assessment of housing status with a licensed clinical social worker and were classified as experiencing housing instability (ie, staying with family or friends, transitional housing, treatment program, shelter, outdoors or vehicle, hotel, or incarcerated) vs not experiencing instability (renting or owning). Multivariable regression models assessed the associations of housing instability with virologic control., Results: Of 232 pregnant patients living with HIV with documented housing status, 41.4% (n=96) experienced housing instability. Patients with housing instability were younger and more likely to self-identify as non-Hispanic Black, have public or no insurance, and have a mental health or substance use disorder. They were less likely to be married, be employed, or have greater than a high school education. There were no differences in parity, number of prenatal visits, or timing of HIV diagnosis between groups. On adjusted analyses, patients with housing instability required an adjusted 2.45 weeks (95% confidence interval, 0.16-4.74) longer to achieve initial viral suppression and had greater odds of missing 5 or more doses of antiretroviral medications (adjusted odds ratio, 2.09; 95% confidence interval, 1.07-4.09) and having a detectable viral load at delivery (adjusted odds ratio, 2.13; 95% confidence interval, 1.02-4.47)., Conclusion: Housing instability among pregnant individuals living with HIV is common and is associated with decreased virologic control during pregnancy. Given the association between virologic control and perinatal transmission, housing instability may be an important social determinant of HIV-related perinatal outcomes. Addressing housing instability during pregnancy may be a critical avenue to improve maternal and neonatal health and reduce the risk of perinatal transmission., (Copyright © 2021 Elsevier Inc. All rights reserved.) more...
- Published
- 2021
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163. Social Vulnerability among Foreign-Born Pregnant Women and Maternal Virologic Control of HIV.
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Premkumar A, Yee LM, Benes L, and Miller ES
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- Adult, Female, HIV Infections ethnology, HIV Infections therapy, Humans, Illinois, Kaplan-Meier Estimate, Pregnancy, Pregnancy Complications, Infectious ethnology, Pregnancy Complications, Infectious therapy, Pregnant People, Retrospective Studies, Emigrants and Immigrants, HIV Infections virology, Pregnancy Complications, Infectious virology, Social Vulnerability, Viremia ethnology
- Abstract
Objective: The aim of this study was to assess whether social vulnerability among foreign-born pregnant women living with HIV is associated with maternal viremia during pregnancy., Study Design: This retrospective cohort study included all foreign-born pregnant women living with HIV who received prenatal care in a multidisciplinary prenatal clinic between 2009 and 2018. A licensed clinical social worker evaluated all women and kept detailed clinical records on immigration status and social support. Social vulnerability was defined as both living in the United States for less than 5 years and reporting no family or friends for support. The primary outcome was evidence of viral non-suppression after achievement of initial suppression. Secondary outcomes were the proportion of women who required > 12 weeks after starting antiretroviral therapy to achieve viral suppression, median time to first viral suppression (in weeks) after initiation of antiretroviral therapy, and the proportion who missed ≥ 5 doses of antiretroviral therapy. Bivariable analyses were performed., Results: A total of 111 foreign-born women were eligible for analysis, of whom 25 (23%) were classified as socially vulnerable. Social and clinical characteristics of women diverged by social vulnerability categorization but no differences reached statistical significance. On bivariable analysis, socially-vulnerable women were at increased risk for needing > 12 weeks to achieve viral suppression (relative risk: 1.78, 95% confidence interval: 1.18-2.67), though there was no association with missing ≥ 5 doses of antiretroviral therapy or median time to viral suppression after initiation of antiretroviral therapy., Conclusion: Among foreign-born, pregnant women living with HIV, markers of virologic control during pregnancy were noted to be worse among socially-vulnerable women. Insofar as maternal viremia is the predominant driver of perinatal transmission, closer clinical surveillance and support may be indicated in this population., Key Points: · 23% of foreign-born pregnant women living with HIV were identified as socially vulnerable.. · Socially-vulnerable women were at higher risk for re-emergent viremia (24 vs. 7%, RR 3.44).. · Socially-vulnerable women were at higher risk for needing >12 weeks to become aviremic (64 vs. 36%, RR: 1.7).., Competing Interests: None declared., (Thieme. All rights reserved.) more...
- Published
- 2021
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164. Hemisensory loss in myasthenia gravis.
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Marshall B, Sharma U, Benes-Lima L, and Rossi FH
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- Aged, Diplopia etiology, Humans, Male, Blepharoptosis etiology, Deglutition Disorders etiology, Myasthenia Gravis complications, Myasthenia Gravis diagnosis, Ophthalmoplegia
- Abstract
A 73-year-old white man presents with left-sided ptosis and diplopia in the absence of ophthalmoplegia, with left hemibody paresthesia. He reports intermittent dysphagia and dizziness for 1 month and diarrhoea for 2 months. Serum and electrodiagnostic studies confirmed the diagnosis of myasthenia gravis. This case highlights the non-classic presentation of myasthenia gravis in the absence of ophthalmoplegia with a unique unexplained hemisensory deficit., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2021. No commercial re-use. See rights and permissions. Published by BMJ.) more...
- Published
- 2021
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165. Genetic rhabdomyolysis within the spectrum of the Spinocerebellar Ataxia type 2 responsive to pregabalin.
- Author
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Rossi F, Ma J, Tsakadze N, Benes-Lima L, Gonzalez JA, and Hoffmann M
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Background: Spinocerebellar Ataxia type 2 is a slowly progressive adult onset ataxia with a broad clinical presentation., Case Presentation: We describe a man with Spinocerebellar Ataxia type 2 with chronic, severe, and recurrent rhabdomyolysis, as part of the cerebellar ataxia genetic spectrum. Initially rhabdomyolysis was refractory to multiple medications, but entirely resolved and remained in chronic remission with pregabalin., Conclusions: This is the first report of Spinocerebellar Ataxia type 2 associated with chronic, severe, recurrent rhabdomyolysis as part of its genetic phenotype responsive to pregabalin. more...
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- 2021
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166. Acute Influenza B Infection Presenting as Cardiac Tamponade: A Case Report.
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Arfaras-Melainis A, Cordero H, Goyal A, Benes L, and Salgunan R
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Influenza A and B acute infections usually affect primarily the respiratory system. In rare cases, however, the cardiovascular system is also compromised either via the direct effect of the virus or via the worsening of preexisting cardiac conditions. We present a rare case of acute Influenza B infection presenting as pericardial effusion and cardiac tamponade. A healthy 32-year-old female was presented to the emergency room with influenza-like symptoms for four days, where she was monitored for a few hours and was subsequently discharged to home after testing positive for Influenza B by polymerase chain reaction (PCR). On the fifth day, she returned to the emergency room with worsening symptoms, primarily exertional dyspnea. She was hypotensive and tachycardic and temporarily improved with fluid administration. She was transferred to the intensive care unit, where a bedside point of care ultrasound (POCUS) and later a formal transthoracic echocardiogram revealed that she had pericardial effusion with sonographic signs of cardiac tamponade. Emergent pericardiocentesis was performed and resulted in hemodynamic and symptomatic improvement. The pericardial drain that was initially left in place and continued to drain pericardial fluid (700 ccs in total), was removed 3 days later, after echocardiographic confirmation of the resolution of the pericardial effusion. She completed a five-day course of Oseltamivir and was subsequently discharged home safely. In summary, our case describes an acute Influenza B infection that was complicated by pericardial effusion and cardiac tamponade. It also highlights the importance of bedside POCUS and echocardiography in the early diagnosis and treatment of cardiac tamponade cases, frequently with pericardiocentesis as in our case., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2020, Arfaras-Melainis et al.) more...
- Published
- 2020
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167. WEDM Used for Machining High Entropy Alloys.
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Mouralova K, Benes L, Zahradnicek R, Bednar J, Zadera A, Fries J, and Kana V
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Unconventional wire electrical discharge machining technology (WEDM) is a key machining process, especially for machining newly emerging materials, as there are almost no restrictions (only at least minimal electrical conductivity) in terms of demands on the mechanical properties of the workpiece or the need to develop new tool geometry. This study is the first to present an analysis of the machinability of newly developed high entropy alloys (HEAs), namely FeCoCrMnNi and FeCoCrMnNiC
0.2 , using WEDM. The aim of this study was to find the optimal setting of machine parameters for the efficient production of parts with the required surface quality without defects. For this reason, an extensive design of experiments consisting of 66 rounds was performed, which took into account the influence of five input factors in the form of pulse off time, gap voltage, discharge current, pulse on time, and wire speed on cutting speed and the quality of the machined surface and its subsurface layer. The analysis of topography, morphology, subsurface layers, chemical composition analysis (EDX), and lamella analysis using a transmission electron microscope (TEM) were performed. An optimal setting of the machine parameters was found, which enables machining of FeCoCrMnNi and FeCoCrMnNiC0.2 with the required surface quality without defects., Competing Interests: The authors declare that they have no conflict of interest. more...- Published
- 2020
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168. Analysis of the Machinability of Copper Alloy Ampcoloy by WEDM.
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Mouralova K, Benes L, Prokes T, Bednar J, Zahradnicek R, Jankovych R, Fries J, and Vontor J
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The unconventional technology of wire electrical discharge machining is widely used in all areas of industry. For this reason, there is always an effort for efficient machining at the lowest possible cost. For this purpose, the following comprehensive study has been carried out to optimize the machining of the copper alloy Ampcoloy 35, which is particularly useful in plastic injection moulds. Within the study, a half-factor experiment of 2
5-1 with 10 axial points and seven central points of a total of 33 rounds was carried out, which was focused on the response monitoring of the input factors in the form of the machine parameters setup: gap voltage, pulse on time, pulse off time, discharge current, and wire speed. Based on the study of the response in the form of cutting speed and surface topography, their statistical models were created, while the optimal setting of machine parameters was determined to maximize the cutting speed and minimize the topography parameters. Further, a detailed cross-sectional analysis of surface and subsurface layer morphology was performed using electron microscopy including chemical composition analysis. In order to study microstructural changes in the material at the atomic level, a lamella was created, which was then studied using a transmission electron microscope. more...- Published
- 2020
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169. The Influence of WEDM Parameters Setup on the Occurrence of Defects When Machining Hardox 400 Steel.
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Mouralova K, Prokes T, Benes L, and Bednar J
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The unconventional technology wire electrical discharge machining is a highly used technology for producing precise and indented shaped parts of all materials that are at least electrically conductive. Its wide use makes this technology applicable in almost all branches of industry, even in the automotive industry, where the abrasion resistant material under investigation Hardox 400 steel is widely used for the manufacturing of truck bodies. The aim of this study was a comprehensive analysis of the machinability of this material using WEDM employing a 33-round experiment. Based on the change in machine parameters (pulse off time, gap voltage, discharge current, pulse on time, and wire feed), the cutting speed, the topography of machined surfaces, and the chemical composition of the workpiece surface, the morphology and condition of the subsurface layer including lamella production and a subsequent determination of the distribution of individual elements in the given area were analyzed. It has been found that during the machining of this steel, many defects occur in the subsurface layer of the material in the form of cracks with a depth of up to 22 µm and burned cavities. However, by appropriately adjusting the machine parameters, it was possible to completely remove these cracks. more...
- Published
- 2019
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170. Combination of low-dose glucocorticosteroids and mineralocorticoids as adjunct therapy for adult patients with septic shock: A systematic review and meta-analysis of randomized trials and observational studies.
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Archontakis Barakakis P, Palaiodimos L, Fleitas Sosa D, Benes L, Gulani P, and Fein D
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Background: The role of the combination of glucocorticosteroids and mineralocorticosteroids in treating septic shock is not well-defined. The aim of this study was to perform a systematic review and meta-analysis of the randomized controlled trials and observational studies assessing the effect of low-dose hydrocortisone and fludrocortisone on patients with septic shock., Materials and Methods: MEDLINE, Scopus, and Cochrane databases were reviewed. A random effect model meta-analysis was used and I -square was used to assess the heterogeneity. Short-term mortality was chosen as our primary end point. A subgroup analysis was performed including only the randomized controlled trials., Results: A total of 10,550 patients were included in this meta-analysis. Administration of the steroid combination was associated with improved short-term mortality (odds ratio, 0.78, confidence interval, 0.64-0.96), intensive care unit mortality, and shock reversal, without increase in steroid-related side effects, such as secondary infection or gastrointestinal hemorrhage., Conclusion: This systematic review and meta-analysis showed that use of the combination of glucocorticosteroids and mineralocorticosteroids has a beneficial impact on short-term mortality, intensive care unit mortality, and shock reversal, without increasing the incidence of gastrointestinal hemorrhage or superinfection in patients with septic shock, when used as an adjunct treatment to the established standard of care., (Copyright: © 2019 Avicenna Journal of Medicine.) more...
- Published
- 2019
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171. Automating Collection of Pain-Related Patient-Reported Outcomes to Enhance Clinical Care and Research.
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Owen-Smith A, Mayhew M, Leo MC, Varga A, Benes L, Bonifay A, and DeBar L
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- Female, Humans, Male, Pain Management methods, Pain Measurement methods, Primary Health Care methods, Program Evaluation, Chronic Pain therapy, Data Collection methods, Patient Reported Outcome Measures
- Abstract
Introduction: Chronic pain is highly prevalent, and the ability to routinely measure patients' pain and treatment response using validated patient-reported outcome (PRO) assessments is important to clinical care. Despite this recognition, systematic use in everyday clinical care is rare., Aims: The aims of this study were to (1) describe infrastructure designed to automate PRO data collection, (2) compare study-enhanced PRO completion rates to those in clinical care, and (3) evaluate patient response rates by method of PRO administration and sociodemographic and/or clinical characteristics., Setting: The Pain Program for Active Coping and Training (PPACT) is a pragmatic clinical trial conducted within three regions of the Kaiser Permanente health care system., Program Description: PPACT evaluates the effect of integrative primary care-based pain management services on outcomes for chronic pain patients on long-term opioid treatment. We implemented a tiered process for quarterly assessment of PROs to supplement clinical collection and ensure adequate trial data using three methods: web-based personal health records (PHR), automated interactive voice response (IVR) calls, and live outreach., Program Evaluation: Among a subset of PPACT participants examined (n = 632), the tiered study-enhanced PRO completion rates were higher than in clinical care: 96% completed ≥ 1 study-administered PRO with mean of 3.46 (SD = 0.85) vs. 74% completed in clinical care with a mean of 2.43 (SD = 2.08). Among all PPACT participants at 3 months (n = 831), PRO completion was 86% and analyses of response by key characteristics found only that participant age predicted an increased likelihood of responding to PHR and IVR outreach., Discussion: Adherence to pain-related PRO data collection using our enhanced tiered approach was high. No demographic or clinical identifiers other than age were associated with differential response by modality. Successful ancillary support should employ multimodal electronic health record functionalities for PRO administration. Using automated modalities is feasible and may facilitate better sustainability for regular PRO administration within health care systems. Clinical Trials Registration Number: NCT02113592. more...
- Published
- 2018
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172. Interdisciplinary team-based care for patients with chronic pain on long-term opioid treatment in primary care (PPACT) - Protocol for a pragmatic cluster randomized trial.
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DeBar L, Benes L, Bonifay A, Deyo RA, Elder CR, Keefe FJ, Leo MC, McMullen C, Mayhew M, Owen-Smith A, Smith DH, Trinacty CM, and Vollmer WM
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- Adult, Female, Humans, Male, Adaptation, Psychological, Analgesics, Opioid administration & dosage, Pain Management methods, Pain Measurement methods, Patient Care Team, Patient Preference psychology, Patient Preference statistics & numerical data, Primary Health Care methods, Recovery of Function drug effects, Treatment Outcome, Pragmatic Clinical Trials as Topic, Behavior Control methods, Chronic Pain diagnosis, Chronic Pain drug therapy, Chronic Pain psychology, Low Back Pain diagnosis, Low Back Pain drug therapy, Low Back Pain psychology, Quality of Life
- Abstract
Background: Chronic pain is one of the most common, disabling, and expensive public health problems in the United States. Interdisciplinary pain management treatments that employ behavioral approaches have been successful in helping patients with chronic pain reduce symptoms and regain functioning. However, most patients lack access to such treatments. We are conducting a pragmatic clinical trial to test the hypothesis that patients who receive an interdisciplinary biopsychosocial intervention, the Pain Program for Active Coping and Training (PPACT), at their primary care clinic will have a greater reduction in pain impact in the year following than patients receiving usual care., Methods/design: This is an effectiveness-implementation hybrid pragmatic clinical trial in which we randomize clusters of primary care providers and their patients with chronic pain who are on long-term opioid therapy to 1) receive an interdisciplinary behavioral intervention in conjunction with their current health care or 2) continue with current health care services. Our primary outcome is pain impact (a composite of pain intensity and pain-related interference) measured using the PEG, a validated three-item assessment. Secondary outcomes include pain-related disability, patient satisfaction, opioids dispensed and health care utilization. An economic evaluation assesses the resources and costs necessary to deliver the intervention and its cost-effectiveness compared with usual care. A formative evaluation employs mixed methods to understand the context for implementation in the participating health care systems., Discussion: This trial will inform the feasibility of implementing interdisciplinary behavioral approaches to pain management in the primary care setting, potentially providing a more effective, safer, and more satisfactory alternative to opioid-based chronic pain treatment. Clinical Trials Registration Number: NCT02113592., (Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.) more...
- Published
- 2018
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173. Atomic Layer Deposition Al 2 O 3 Coatings Significantly Improve Thermal, Chemical, and Mechanical Stability of Anodic TiO 2 Nanotube Layers.
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Zazpe R, Prikryl J, Gärtnerova V, Nechvilova K, Benes L, Strizik L, Jäger A, Bosund M, Sopha H, and Macak JM
- Abstract
We report on a very significant enhancement of the thermal, chemical, and mechanical stability of self-organized TiO
2 nanotubes layers, provided by thin Al2cript> O 3 coatings of different thicknesses prepared by atomic layer deposition (ALD). TiO2 nanotube layers coated with Al2 O3 coatings exhibit significantly improved thermal stability as illustrated by the preservation of the nanotubular structure upon annealing treatment at high temperatures (870 °C). In addition, a high anatase content is preserved in the nanotube layers against expectation of the total rutile conversion at such a high temperature. Hardness of the resulting nanotube layers is investigated by nanoindentation measurements and shows strongly improved values compared to uncoated counterparts. Finally, it is demonstrated that Al2 O3 coatings guarantee unprecedented chemical stability of TiO2 nanotube layers in harsh environments of concentrated H3 PO4 solutions. more...- Published
- 2017
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174. Qualitative Assessment of Patients Receiving Prolotherapy for Knee Osteoarthritis in a Multimethod Study.
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Rabago D, van Leuven L, Benes L, Fortney L, Slattengren A, Grettie J, and Mundt M
- Subjects
- Cohort Studies, Female, Glucose administration & dosage, Glucose therapeutic use, Humans, Interviews as Topic, Male, Middle Aged, Randomized Controlled Trials as Topic, Complementary Therapies methods, Complementary Therapies psychology, Osteoarthritis, Knee drug therapy, Patient Satisfaction, Regenerative Medicine methods
- Abstract
Objective: Randomized and open-label studies assessing prolotherapy for knee osteoarthritis have found quantitative improvement on the validated Western Ontario McMaster University Osteoarthritis Index (WOMAC) compared with baseline status and control therapies. This study assessed the qualitative response of participants receiving prolotherapy, an injection-based complementary treatment for symptomatic knee osteoarthritis (OA)., Design: Qualitative study using semi-structured in-depth interviews at 52 weeks after enrollment; transcribed responses were discussed by coauthors to identify themes; disagreement was resolved by consensus., Setting: Outpatient., Participants: Twenty-two participants treated with prolotherapy for symptomatic knee OA who were exited from three randomized and open-label studies., Interventions: Intra- and extra-articular hypertonic dextrose injection (prolotherapy)., Main Outcome Measures: Patient narrative and composite WOMAC questionnaire (0-100 points) scores., Results: Participants had baseline demographic and knee OA severity similar to those of participants in three prior intervention trials, as well as similar robust follow-up WOMAC score change (19.9 ± 12.6 points), suggesting a representative subsample. Seven themes were identified from participant narratives: (1) improvement in knee-specific quality of life (n = 18), (2) safety and comfort, (3) pretreatment counseling enhanced treatment adherence and optimism, (4) overall positive experience with prolotherapy, (5) limited response to prolotherapy (n = 4), (6) consistency with anecdotal clinical prolotherapy experience; and (7) functional improvement without pain reduction., Conclusions: Most participants reported substantially improved knee-specific effects, resulting in improved quality of life and activities of daily living; four participants reported minimal or no effect. Clear, complete description of procedural rationale may enhance optimism about and adherence to treatment appointments., Competing Interests: Author Disclosure Statement No competing financial interests exist. more...
- Published
- 2016
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175. Treatment of Central Deafferentation and Trigeminal Neuropathic Pain by Motor Cortex Stimulation: Report of a Series of 20 Patients.
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Kolodziej MA, Hellwig D, Nimsky C, and Benes L
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- Adult, Aged, Deep Brain Stimulation, Denervation, Electric Stimulation Therapy instrumentation, Electrodes, Implanted, Epidural Space, Female, Follow-Up Studies, Humans, Magnetic Resonance Imaging, Male, Middle Aged, Neurosurgical Procedures, Retrospective Studies, Treatment Outcome, Central Nervous System injuries, Electric Stimulation Therapy methods, Motor Cortex, Neuralgia therapy, Trigeminal Neuralgia therapy
- Abstract
Objective: Motor cortex stimulation (MCS) is an alternative treatment modality for central neuropathic pain, if conservative treatment failed. Study aim was outcome assessment after MCS., Material and Methods: This study is a retrospective case series review of patients who had undergone MCS for central pain (n = 8), deafferentation pain (n = 3) and neuropathic trigeminal pain (n = 9) between April 2001 and May 2011. In all patients, four contact-paddle electrodes were placed in the epidural space overlying the motor cortex via burr hole trepanation under local anesthesia. The follow-up period was 6 months to 6 years. Pain control was assessed by the visual analog scale (VAS)., Results: A total of 22 patients (11 men, 11 women) were treated; after trial stimulation two male patients were excluded for incompliance reasons. The mean patient age was 59.8 years (range: 31-79 years). In the central pain group, three patients reported complete, and four patients satisfactory pain control. In the trigeminal neuropathic pain group, seven patients reported complete, and two patients satisfactory pain control. In the deafferentation pain group, one patient reported complete, and two patients satisfactory pain control. None of the patients showed new neurologic deficits after the MCS., Conclusions: MCS is an effective treatment modality for central neuropathic pain and trigeminal pain with low morbidity and mortality. Future studies are necessary to evaluate and optimize this treatment option in more detail., (Georg Thieme Verlag KG Stuttgart · New York.) more...
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- 2016
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176. Reversible cortical blindness and internuclear ophthalmoplegia after neurosurgical operation: case report and review of the literature.
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Kuhnt D, Becker A, Benes L, and Nimsky C
- Subjects
- Blindness, Cortical therapy, Brain Neoplasms surgery, Hemangiopericytoma surgery, Humans, Infratentorial Neoplasms surgery, Magnetic Resonance Imaging, Male, Middle Aged, Neurologic Examination, Ocular Motility Disorders therapy, Posterior Leukoencephalopathy Syndrome, Blindness, Cortical etiology, Neurosurgical Procedures adverse effects, Ocular Motility Disorders etiology, Postoperative Complications therapy
- Abstract
Background: The reversible posterior leukoencephalopathy (RPL) syndrome with typical vasogenic edema in the occipital lobe and associated cortical blindness is a rare finding; however, the brainstem variant is even more infrequent. Etiologies discussed include blood pressure dysregulations, renal failure, or immunosuppression., Patient: A 63-year-old man with the characteristic radiographic findings of RPL syndrome presented with reversible cortical blindness and internuclear ophthalmoplegia (INO) after resection of an infratentorial hemangiopericytoma. The patient postoperatively presented with diplopia and mental status alterations followed by visual loss; these symptoms completely recovered within a few days. Fluid-attenuated inversion recovery-, and T2-weighted magnetic resonance imaging (MRI) revealed bilateral hyperintense lesions not only in the white matter of the parieto-occipital region but also in the rostral paramedian mesencephalon and pons., Conclusions: We hypothesize that the patient had an RPL, coincidentally in classic-, and brainstem localization, caused by perioperative fluctuations of blood pressure., (Georg Thieme Verlag KG Stuttgart · New York.) more...
- Published
- 2013
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177. Comparison of different reconstruction algorithms for three-dimensional ultrasound imaging in a neurosurgical setting.
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Miller D, Lippert C, Vollmer F, Bozinov O, Benes L, Schulte DM, and Sure U
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- Brain pathology, Brain surgery, Computer Simulation, Echoencephalography statistics & numerical data, Humans, Image Processing, Computer-Assisted statistics & numerical data, Magnetic Resonance Imaging statistics & numerical data, Algorithms, Imaging, Three-Dimensional statistics & numerical data, Neurosurgical Procedures statistics & numerical data, Surgery, Computer-Assisted statistics & numerical data
- Abstract
Background: Freehand three-dimensional ultrasound imaging (3D-US) is increasingly used in image-guided surgery. During image acquisition, a set of B-scans is acquired that is distributed in a non-parallel manner over the area of interest. Reconstructing these images into a regular array allows 3D visualization. However, the reconstruction process may introduce artefacts and may therefore reduce image quality. The aim of the study is to compare different algorithms with respect to image quality and diagnostic value for image guidance in neurosurgery., Methods: 3D-US data sets were acquired during surgery of various intracerebral lesions using an integrated ultrasound-navigation device. They were stored for post-hoc evaluation. Five different reconstruction algorithms, a standard multiplanar reconstruction with interpolation (MPR), a pixel nearest neighbour method (PNN), a voxel nearest neighbour method (VNN) and two voxel based distance-weighted algorithms (VNN2 and DW) were tested with respect to image quality and artefact formation. The capability of the algorithm to fill gaps within the sample volume was investigated and a clinical evaluation with respect to the diagnostic value of the reconstructed images was performed., Results: MPR was significantly worse than the other algorithms in filling gaps. In an image subtraction test, VNN2 and DW reliably reconstructed images even if large amounts of data were missing. However, the quality of the reconstruction improved, if data acquisition was performed in a structured manner. When evaluating the diagnostic value of reconstructed axial, sagittal and coronal views, VNN2 and DW were judged to be significantly better than MPR and VNN., Conclusion: VNN2 and DW could be identified as robust algorithms that generate reconstructed US images with a high diagnostic value. These algorithms improve the utility and reliability of 3D-US imaging during intraoperative navigation., (Copyright © 2012 John Wiley & Sons, Ltd.) more...
- Published
- 2012
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178. Management of supratentorial intracerebral hemorrhage-still a controversy?
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Benes L and Nimsky C
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- Female, Humans, Male, Intracranial Hemorrhages therapy, Stereotaxic Techniques, Suction methods, Thalamic Diseases therapy, Thrombolytic Therapy methods
- Published
- 2012
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179. Intraoperative ultrasound assistance in treatment of intradural spinal tumours.
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Zhou H, Miller D, Schulte DM, Benes L, Bozinov O, Sure U, and Bertalanffy H
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- Aged, Aged, 80 and over, Edema diagnosis, Edema pathology, Female, Humans, Magnetic Resonance Imaging, Male, Middle Aged, Monitoring, Intraoperative, Neoplasm Metastasis, Spinal Cord diagnostic imaging, Spinal Cord surgery, Surgery, Computer-Assisted, Ultrasonography, Neurosurgical Procedures methods, Spinal Cord Neoplasms diagnostic imaging, Spinal Cord Neoplasms surgery
- Abstract
Objective: Currently, the standard practice to treat intradural spinal tumours involves microsurgical resection of the lesions. It is essential to be able to locate the lesion precisely to reduce the risk of neurological morbidity. The purpose of this study was to evaluate intraoperative ultrasonography (IOUS) in visualizing intradural spinal tumours, and assess its potential to improve surgical precision and minimize surgical trauma., Methods: Between January 2006 and July 2007, 30 patients with suspected intradural spinal tumours underwent surgery with the aid of IOUS. There were 13 patients with intramedullary tumours (ependymoma=2, astrocytoma=5, hemangioblastoma=2 and metastasis=4); and 14 patients with extramedullary tumours (meningioma=6, neurinoma=6, filum terminale ependymoma=1 and lipoma=1). In 3 patients histopathology did not reveal any neoplasm despite an MRI suggesting tumour. Their sonographic features are analyzed and the advantages of IOUS are discussed., Results: The shape and expansion of intradural tumours could be visualized on IOUS. The sonographic visualization allowed adapting the approach to an appropriate location and size before dura opening. Certain sonographic features can be used for a differential diagnosis of different intradural tumours. In addition, IOUS can inform neurosurgeons about the location of the neoplastic tissue, its relation to the spinal cord and the size of residual tumour following excision., Conclusions: IOUS is a sensitive intraoperative tool. When appropriately applied to assist surgical procedures, it offers additional intraoperative information that helps to improve surgical precision and therefore might reduce the procedure related morbidity., (Copyright © 2011 Elsevier B.V. All rights reserved.) more...
- Published
- 2011
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180. Quality of life after brainstem cavernoma surgery in 71 patients.
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Dukatz T, Sarnthein J, Sitter H, Bozinov O, Benes L, Sure U, and Bertalanffy H
- Subjects
- Adolescent, Adult, Aged, Cerebral Hemorrhage etiology, Child, Gait Disorders, Neurologic etiology, Humans, Magnetic Resonance Imaging, Male, Microsurgery, Middle Aged, Neurologic Examination, Neuropsychological Tests, Neurosurgical Procedures, Postoperative Complications, Postoperative Period, Treatment Outcome, Young Adult, Brain Stem surgery, Hemangioma, Cavernous psychology, Hemangioma, Cavernous surgery, Quality of Life
- Abstract
Background: Symptomatic patients with a brainstem cavernoma are treated surgically with increasing frequency. Generally, the patient's benefit from this difficult surgical intervention is quantified by the assessment of neurological symptoms., Objective: To document the beneficial effect of surgery in a larger patient population by assessing the postoperative quality of life (QoL)., Methods: In a series of 71 surgically treated patients, a detailed neurological status was assessed by Patzold Rating and Karnofsky Performance Status Scale. Patients rated their QoL with the Short Form 36 Health Survey. To document the effect of surgery on QoL, we devised a supplementary questionnaire. The last 24 patients completed Short Form 36 Health Survey pre- and postoperatively., Results: Karnofsky Performance Status Scale improved in 44 of 71 surgical patients (62%), remained unchanged in 19 (27%), and deteriorated in 8 (11%) individuals. Patzold Rating showed a more detailed picture of the neurological symptoms. It correlated significantly with Karnofsky Performance Status Scale, which underscores its usefulness for patients with brainstem lesions. In the Short Form 36 Health Survey score, the Mental Component Summary improved with surgery (paired test, P = .015). In addition, 58 individuals (82%) declared a clear subjective benefit of surgery., Conclusion: The results of this large series support the notion that microsurgical removal of a brainstem cavernoma represents an effective therapy in experienced hands and is generally associated with good clinical outcome, both neurologically and in terms of QoL. more...
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- 2011
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181. Stand-alone 3D-ultrasound navigation after failure of conventional image guidance for deep-seated lesions.
- Author
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Miller D, Benes L, and Sure U
- Subjects
- Adolescent, Adult, Anticonvulsants therapeutic use, Brain pathology, Brain surgery, Central Nervous System Vascular Malformations diagnostic imaging, Epilepsy drug therapy, Epilepsy etiology, Epilepsy surgery, Equipment Failure, Female, Humans, Image Processing, Computer-Assisted, Magnetic Resonance Imaging, Nervous System Diseases etiology, Neurologic Examination, Thalamic Diseases diagnostic imaging, Thalamic Diseases surgery, Treatment Outcome, Ultrasonography, Central Nervous System Vascular Malformations surgery, Imaging, Three-Dimensional methods, Neuronavigation methods, Surgery, Computer-Assisted
- Abstract
Image guidance has proven to be an important tool in surgery for deep-seated or eloquently located cavernomas. However, neuronavigation depending on preoperative images can fail. Thus, the displayed anatomy might be distorted already during the approach. This report demonstrates the use of three-dimensional intraoperative ultrasound (3D-US) as a rescue tool, when conventional navigation is erroneous. Two patients with symptomatic cavernomas, the one located subcortically in the right peritrigonum, the other in the left thalamus, were operated in our clinic via an image-guided approach. An integrated ultrasound-navigation system was used for neuronavigation. In both cases, navigation based on preoperative MRI failed after the craniotomy because patient-to-image registration was lost. In both cases, a simple registration of the patient's orientation was performed. Then a 3D-US volume was acquired and navigation was performed using the 3D-US data set. This is accurate as image acquisition and navigation are done in the same system. The cavernoma was visualized without difficulties in both cases. It could be reached directly via the ultrasound-guided approach. Patients' symptoms improved postoperatively and a complete resection could be documented. Two cavernomas were successfully resected using 3D-US guidance. In our experience, stand-alone 3D-US navigation is an effective option if conventional MRI-based navigation fails. more...
- Published
- 2011
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182. The role of underlying structural cause for epilepsy classification: clinical features and prognosis in mesial temporal lobe epilepsy caused by hippocampal sclerosis versus cavernoma.
- Author
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Menzler K, Thiel P, Hermsen A, Chen X, Benes L, Miller D, Sure U, Knake S, and Rosenow F
- Subjects
- Adult, Atrophy, Brain Neoplasms complications, Brain Neoplasms diagnosis, Diagnosis, Differential, Epilepsy, Temporal Lobe etiology, Female, Hemangioma, Cavernous, Central Nervous System complications, Hemangioma, Cavernous, Central Nervous System diagnosis, Humans, Male, Middle Aged, Sclerosis, Young Adult, Brain Neoplasms pathology, Epilepsy, Temporal Lobe classification, Epilepsy, Temporal Lobe pathology, Hemangioma, Cavernous, Central Nervous System pathology, Hippocampus pathology
- Abstract
Purpose: The recent "Report of the ILAE Commission on Classification and Terminology" recommends an epilepsy classification that gives more emphasis to the underlying structural or metabolic cause rather than to the localization of the epileptogenic zone. The aim of the present study was to investigate differences in clinical features, treatment response, and prognosis in patients with mesial temporal lobe epilepsy (MTLE) caused by hippocampal sclerosis (MTLE-HS) or singular mesiotemporal cavernomas (MTLE-C) in order to evaluate the impact of underlying pathology on the course of the disease while controlling for localization., Methods: Age at onset, age at surgery, seizure frequency and semiology, pharmacoresistance, psychiatric comorbidities, memory deficits, or initial precipitating insults (e.g., febrile seizures, traumatic brain injury, infection of the central nervous system, birth complications) as well as postoperative outcome were compared in eleven patients with MTLE-C and 33 patients with MTLE-HS using nonparametric statistical methods., Key Findings: The postoperative outcome was significantly better in patients with MTLE-C, even after controlling for preoperative epilepsy duration. Patients with MTLE-HS more frequently were drug resistant (88% vs. 36%) and more often presented with an initial precipitating insult (70% vs. 27%) and with automotor seizures (79% vs. 46%)., Significance: The results suggest that patients with MTLE-C show a more favorable postoperative outcome, supporting the commission's suggestion to put more emphasis on the underlying cause in future epilepsy classifications., (Wiley Periodicals, Inc. © 2011 International League Against Epilepsy.) more...
- Published
- 2011
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183. A 54-year-old woman with a meningeal lesion compressing the medulla oblongata.
- Author
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Kolodziej M, Benes L, Nimsky C, Schaefer HE, and Pagenstecher A
- Subjects
- Female, Humans, Magnetic Resonance Imaging methods, Meninges injuries, Middle Aged, Brain Injuries pathology, Medulla Oblongata pathology, Meninges pathology
- Abstract
A 54-year-old woman had nausea, vomiting and personality changes since a few weeks. Paresis of the abducens and hypoglossal nerves on the left side, a right sided reduction of the visual field, discrete dysarthri×a and ataxia were diagnosed. Cranial magnetic resonance imaging demonstrated a contrast enhancing circular meningeal lesion of the foramen magnum. Histological examination revealed a granulomatous lesion of the meninges with focal necrosis, vasculitis and neutrophils indicating immune complex reactions. A diagnosis of primary meningeal Wegener's disease was made. Medication with low dose prednisolone led to complete remission of the lesion 1.5 years later. more...
- Published
- 2010
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184. Nonconventional behavior of NCN-chelated organoantimony(III) sulfide and isolation of cyclic organoantimony(III) bis(pentasulfide).
- Author
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Dostál L, Jambor R, Růzicka A, Jirásko R, Lochar V, Benes L, and de Proft F
- Abstract
Organoantimony(III) sulfide (1) containing the NCN chelating ligand L [L = 2,6-(CH(2)NMe(2))(2)C(6)H(3)] displays unusual dual behavior, being dimeric (LSbS)(2), with the central Sb(2)S(2) core, in the solid state but monomeric in solution. Sulfide 1 reacts with elemental S to give the unprecedented cyclic bis(pentasulfide) LSb(mu-S(5))(2)SbL (2) with the central 12-membered ring Sb(2)S(10). more...
- Published
- 2009
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185. Transsulcal approach supported by navigation-guided neurophysiological monitoring for resection of paracentral cavernomas.
- Author
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Zhou H, Miller D, Schulte DM, Benes L, Rosenow F, Bertalanffy H, and Sure U
- Subjects
- Adolescent, Adult, Aged, Brain Mapping methods, Central Nervous System Neoplasms surgery, Evoked Potentials, Motor physiology, Evoked Potentials, Somatosensory physiology, Female, Hemangioma, Cavernous, Central Nervous System surgery, Humans, Image Processing, Computer-Assisted methods, Intralaminar Thalamic Nuclei pathology, Intralaminar Thalamic Nuclei physiopathology, Intralaminar Thalamic Nuclei surgery, Magnetic Resonance Imaging methods, Male, Middle Aged, Minimally Invasive Surgical Procedures methods, Motor Cortex pathology, Motor Cortex physiopathology, Motor Cortex surgery, Treatment Outcome, Young Adult, Central Nervous System Neoplasms physiopathology, Hemangioma, Cavernous, Central Nervous System physiopathology, Monitoring, Intraoperative methods, Neuronavigation methods
- Abstract
Objectives: The aim of the study is to evaluate tools that can improve surgical precision and minimize surgical trauma for removal of cavernomas in the paracentral area. Moreover, the surgical strategies for the treatment of symptomatic epilepsy in cavernoma patients are discussed., Patients and Methods: Between June 2000 and July 2007, 17 patients suffering from paracentral cavernoma underwent surgery via a transsulcal approach with the aid of neuronavigation, functional mapping and neurophysiological intraoperative monitoring. To optimize outcome for procedures in the paracentral area, the hemosiderin-stained tissue was removed entirely except for a small proportion on the side of precentral gyrus., Results: All cavernomas and their adjacent sulci could be precisely located with the aid of ultrasonography-assisted neuronavigation. By combining preoperative fMRI and intraoperative neurophysiological monitoring, including SEP, MEP and cortical mapping, the motor cortex could be defined in all cases. Thus damage to the primary motor area could be avoided during resection of cavernomas. All the lesions located in the paracentral area were removed completely via transsulcal microsurgical approach without neurological deficits. No significant seizures were induced during surgery., Conclusions: The successful excision of these lesions was effected by the following four key factors: (1) the precise location of the lesion supported by intraoperative neuronavigation; (2) the preservation of the eloquent area with the aid of functional mapping; (3) a minimally invasive transsulcal microsurgical approach; and (4) the entire removal of cavernoma and hemosiderin-stained tissue. more...
- Published
- 2009
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186. Structure analysis of hydrotalcite intercalated with pyrenetetrasulfonate; experiments and molecular modelling.
- Author
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Veteska M, Pospísil M, Melánová K, Benes L, and Zima V
- Subjects
- Anions chemistry, Computer Simulation, Hydroxides chemistry, X-Ray Diffraction, Zinc chemistry, Aluminum Hydroxide chemistry, Magnesium Hydroxide chemistry, Models, Molecular, Pyrenes chemistry
- Abstract
The structure of pyrenetetrasulfonate intercalated with hydrotalcite, having the formula [Zn(0.68)Al(0.32)(OH)(2)][(C(16)H(6)O(12)S(4))(0.08) . x H(2)O], was proposed based on molecular simulations combined with experimental data (X-ray powder diffraction, thermogravimetry). Calculations were done for samples kept at various relative humidities (0%, 84%, 98%). The appropriate models were selected from comparison of calculated and measured diffraction patterns. Modelling revealed the arrangement of pyrenetetrasulfonate anions, and the positions and the amount of water molecules in the interlayer space of the host structure. The results confirmed a large variability in the arrangement of the guest species. In the sample without water molecules (0% RH), pyrenetetrasulfonate anions formed a layer at the centre of the interlayer distance. For the sample kept at 84% RH, the anions formed two layers at the thirds of the interlayer. For the sample kept at 98% RH, the anions became tilted with respect to the layered double hydroxides (LDH) layers and are less organised. Water molecules were arranged in three distinct planes: one in the middle and two at the quarters of interlayer distance. The number of water molecules obtained by the modelling basically agrees with the water content as measured by thermogravimetry. more...
- Published
- 2008
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187. Synthesis and structure-activity relationship studies of theophylline analogs on population responses in the rat hippocampus in vitro.
- Author
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Ananthalakshmi KV, Bartl T, Aziza MH, Novotný L, Marek R, Benes L, and Kombian SB
- Subjects
- Action Potentials drug effects, Animals, Dose-Response Relationship, Drug, Drug Evaluation, Preclinical, Electrodes, Hippocampus cytology, Hippocampus physiology, Male, Molecular Structure, Neurons classification, Neurons physiology, Rats, Rats, Sprague-Dawley, Stereoisomerism, Structure-Activity Relationship, Theophylline analogs & derivatives, Time Factors, Hippocampus drug effects, Neurons drug effects, Nootropic Agents chemical synthesis, Nootropic Agents pharmacology, Theophylline chemical synthesis, Theophylline pharmacology
- Abstract
We synthesized several theophylline analogs and tested the hypothesis that these compounds may be nootropic or cognitive enhancers by examining their effects on evoked population spikes recorded extracellularly in the CA1 region of the rat hippocampus. Whereas the length of the carbon chain on N7 had no effect, different size of the terminal lactam ring strongly influenced neuroactivity. Our results suggest that hexahydroazepin-2-one analogs have potential for further development as cognitive enhancers. more...
- Published
- 2008
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188. Spatio-Temporal Modelling of Dust Transport over Surface Mining Areas and Neighbouring Residential Zones.
- Author
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Matejicek L, Janour Z, Benes L, Bodnar T, and Gulikova E
- Abstract
Projects focusing on spatio-temporal modelling of the living environment need to manage a wide range of terrain measurements, existing spatial data, time series, results of spatial analysis and inputs/outputs from numerical simulations. Thus, GISs are often used to manage data from remote sensors, to provide advanced spatial analysis and to integrate numerical models. In order to demonstrate the integration of spatial data, time series and methods in the framework of the GIS, we present a case study focused on the modelling of dust transport over a surface coal mining area, exploring spatial data from 3D laser scanners, GPS measurements, aerial images, time series of meteorological observations, inputs/outputs form numerical models and existing geographic resources. To achieve this, digital terrain models, layers including GPS thematic mapping, and scenes with simulation of wind flows are created to visualize and interpret coal dust transport over the mine area and a neighbouring residential zone. A temporary coal storage and sorting site, located near the residential zone, is one of the dominant sources of emissions. Using numerical simulations, the possible effects of wind flows are observed over the surface, modified by natural objects and man-made obstacles. The coal dust drifts with the wind in the direction of the residential zone and is partially deposited in this area. The simultaneous display of the digital map layers together with the location of the dominant emission source, wind flows and protected areas enables a risk assessment of the dust deposition in the area of interest to be performed. In order to obtain a more accurate simulation of wind flows over the temporary storage and sorting site, 3D laser scanning and GPS thematic mapping are used to create a more detailed digital terrain model. Thus, visualization of wind flows over the area of interest combined with 3D map layers enables the exploration of the processes of coal dust deposition at a local scale. In general, this project could be used as a template for dust-transport modelling which couples spatial data focused on the construction of digital terrain models and thematic mapping with data generated by numerical simulations based on Reynolds averaged Navier-Stokes equations. more...
- Published
- 2008
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189. Layered double hydroxide intercalated with p-methylbenzoate and p-bromobenzoate: molecular simulations and XRD analysis.
- Author
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Kovár P, Melánová K, Zima V, Benes L, and Capková P
- Abstract
Samples of Mg4Al2 layered double hydroxide (LDH) intercalated with p-methylbenzoate and p-bromobenzoate anions were prepared by reconstruction of calcined LDH. The interlayer arrangement of guests was investigated by molecular modeling combined with X-ray powder diffraction and thermogravimetry. Molecular modeling was carried out in a Cerius2 modeling environment. In both structures the guest anions adopt a nearly perpendicular arrangement of their long axis with respect to the host layers and they are anchored to the OH groups of the layers through COO* groups via electrostatic interactions. Molecular modeling revealed that both structures of the intercalates exhibit a certain disorder of guest anions in the interlayer space. In the case of LDH-p-methylbenzoate intercalate the anions tend to be situated in disordered rows, and the LDH-p-bromobenzoate intercalate exhibits a total disorientation of guest anions. A good agreement between calculated and measured X-ray diffraction patterns and between experimental and calculated basal spacings was obtained. In the LDH-p-methylbenzoate intercalate d exp=16.96 A and d calc=16.97 A, and in the case of LDH-p-bromobenzoate intercalate d exp=17.19 A and d calc=17.40 A. more...
- Published
- 2008
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190. [Substances modifying the activity of caspases].
- Author
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Bartl T, Zádníková P, Jiríkovská R, Marousková B, and Benes L
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- Apoptosis drug effects, Apoptosis physiology, Caspases physiology, Enzyme Activation drug effects, In Vitro Techniques, Caspases chemistry, Caspases drug effects
- Abstract
Caspases are enzymes which play a key role in programmed cell death--apoptosis. Dysregulation of this process results in a series of disorders in which apoptosis is involved in pathogenesis. Diseases could be divided into two groups--diseases with pathological inhibition of apoptosis (cancer, some autoimmune disorders) and diseases with pathological induction of apoptosis (neurodegenerative disorders, AIDS). The paper lists the most significant activators and inhibitors of caspases as they control apoptosis and hence they are widely studied nowadays. The effects of stobadine, theophylline and adenine derivatives on the activity of caspase 1 was investigated with the use of spectrophotometry. The compounds under study showed an inhibitory effect on the enzyme tested; in one case the inhibitory effect exceeded 80%. more...
- Published
- 2008
191. Candidate genes for the progression of malignant gliomas identified by microarray analysis.
- Author
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Bozinov O, Köhler S, Samans B, Benes L, Miller D, Ritter M, Sure U, and Bertalanffy H
- Subjects
- Basic Helix-Loop-Helix Transcription Factors genetics, Disease Progression, Humans, Interleukin-13 Receptor alpha2 Subunit genetics, Nerve Tissue Proteins genetics, Oligodendrocyte Transcription Factor 2, Reverse Transcriptase Polymerase Chain Reaction, Astrocytoma genetics, Brain Neoplasms genetics, Gene Expression Profiling, Glioblastoma genetics, Oligonucleotide Array Sequence Analysis
- Abstract
Malignant astrocytomas of World Health Organization (WHO) grade III or IV have a reduced median survival time, and possible pathways have been described for the progression of anaplastic astrocytomas and glioblastomas, but the molecular basis of malignant astrocytoma progression is still poorly understood. Microarray analysis provides the chance to accelerate studies by comparison of the expression of thousands of genes in these tumours and consequently identify targeting genes. We compared the transcriptional profile of 4,608 genes in tumours of 15 patients including 6 anaplastic astrocytomas (WHO grade III) and 9 glioblastomas (WHO grade IV) using microarray analysis. The microarray data were corroborated by real-time reverse transcription-polymerase chain reaction analysis of two selected genes. We identified 166 gene alterations with a fold change of 2 and higher whose mRNA levels differed (absolute value of the t statistic of 1.96) between the two malignant glioma groups. Further analyses confirmed same transcription directions for Olig2 and IL-13Ralpha2 in anaplastic astrocytomas as compared to glioblastomas. Microarray analyses with a close binary question reveal numerous interesting candidate genes, which need further histochemical testing after selection for confirmation. IL-13Ralpha2 and Olig2 have been identified and confirmed to be interesting candidate genes whose differential expression likely plays a role in malignant progression of astrocytomas. more...
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- 2008
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192. Surgery of intracranial aneurysms previously treated endovascularly.
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Tirakotai W, Sure U, Yin Y, Benes L, Schulte DM, Bien S, and Bertalanffy H
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- Adult, Angioplasty, Embolization, Therapeutic, Female, Humans, Intracranial Aneurysm diagnostic imaging, Male, Middle Aged, Radiography, Retreatment, Treatment Outcome, Intracranial Aneurysm surgery
- Abstract
Objective: To perform a retrospective study on the patients who underwent aneurysmal surgery following endovascular treatment., Patients and Methods: We performed a retrospective study on eight patients who underwent aneurysmal surgery following endovascular treatment (-attempts) with gugliemi detachable coils (GDCs). The indications for surgery, surgical techniques and clinical outcomes were analyzed., Results: The indications for surgical treatment after GDC coiling of aneurysm were classified into three groups. First group: surgery of incompletely coiled aneurysms (n=4). Second group: surgery of mass effect on the neural structures due to coil compaction or rebleeding (n=2). Third group: surgery of vascular complications after endovascular procedure due to parent artery occlusion or thrombus propagation from aneurysm (n=2). Aneurysm obliterations could be performed in all cases confirmed by postoperative angiography. Six patients had an excellent outcome and returned to their profession. Patient's visual acuity was improved. One individual experienced right hemiparesis (grade IV/V) and hemihypesthesia., Conclusions: Microsurgical clipping is rarely necessary for previously coiled aneurysms. Surgical treatment is uncommonly required when an acute complication arises during endovascular treatment, or when there is a dynamic change of a residual aneurysm configuration over time that is considered to be insecure. more...
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- 2007
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193. Image-guided transsylvian, transinsular approach for insular cavernous angiomas.
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Tirakotai W, Sure U, Benes L, Krischek B, Bien S, and Bertalanffy H
- Abstract
Objective: Surgical treatment of cavernomas arising in the insula is especially challenging because of the proximity to the internal capsule and lenticulostriate arteries. We present our technique of image guidance for operations on insular cavernomas and assess its clinical usefulness., Methods: Between 1997 and 2003, with the guidance of a frameless stereotactic system (BrainLab AG, Munich, Germany), we operated on eight patients who harbored an insular cavernoma. Neuronavigation was used for 1) accurate planning of the craniotomy, 2) identification of the distal sylvian fissure, and, finally, 3) finding the exact site for insular corticotomy. Postoperative clinical and neuroradiological evaluations were performed in each patient., Results: The navigation system worked properly in all eight neurosurgical patients. Exact planning of the approach and determination of the ideal trajectory of dissection toward the cavernoma was possible in every patient. All cavernomas were readily identified and completely removed by use of microsurgical techniques. No surgical complications occurred, and the postoperative course was uneventful in all patients., Conclusion: Image guidance during surgery for insular cavernomas provides high accuracy for lesion targeting and permits excellent anatomic orientation. Accordingly, safe exposure can be obtained because of a tailored dissection of the sylvian fissure and minimal insular corticotomy. more...
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- 2007
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194. Is the image guidance of ultrasonography beneficial for neurosurgical routine?
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Miller D, Heinze S, Tirakotai W, Bozinov O, Sürücü O, Benes L, Bertalanffy H, and Sure U
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- Adolescent, Adult, Aged, Aged, 80 and over, Brain Neoplasms pathology, Child, Equipment Design, Female, Humans, Intraoperative Care instrumentation, Magnetic Resonance Imaging, Male, Middle Aged, Preoperative Care, Retrospective Studies, Brain Neoplasms diagnostic imaging, Brain Neoplasms surgery, Neurosurgical Procedures instrumentation, Neurosurgical Procedures methods, Surgery, Computer-Assisted instrumentation, Surgery, Computer-Assisted standards, Ultrasonography, Doppler instrumentation
- Abstract
Background: Intraoperative US has been widely used in neurosurgical procedures. However, images are often difficult to read. In the present study, we evaluate whether the image guidance of ultrasonography is helpful for the interpretation of US scans., Methods: Twenty-nine patients with tumor were operated on with the aid of intraoperative US from January to June 2005. Image-guided sonography was used in 13 cases and nonnavigated US technology in the remaining cases. We compared the 2 technologies retrospectively., Results: Although image quality was good in most cases, orientation remained difficult in 8 of the 16 patients where conventional sonography was used. With the aid of image fusion for navigated sonography, the orientation was judged superior to nonnavigated US., Conclusion: In our experience, integration of the US into the navigation system facilitates anatomical understanding. Thus, we feel that this technology is beneficial for neurosurgical routine. more...
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- 2007
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195. Surgical management of dural arteriovenous fistulas with transosseous arterial feeders involving the jugular bulb.
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Tirakotai W, Benes L, Kappus C, Sure U, Farhoud A, Bien S, and Bertalanffy H
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- Aged, Cerebral Angiography, Female, Humans, Magnetic Resonance Angiography, Male, Middle Aged, Neurologic Examination, Retrospective Studies, Tinnitus etiology, Tomography, X-Ray Computed, Treatment Outcome, Arteriovenous Fistula pathology, Arteriovenous Fistula surgery, Cerebral Arteries pathology, Jugular Veins pathology, Neurosurgical Procedures
- Abstract
Dural arteriovenous fistulas located in the vicinity of the jugular foramen are complex vascular malformations and belong to the most challenging skull base lesions to treat. The authors comprehensively analyze multiple features in a series of dural arteriovenous fistulas with transosseous arterial feeders involving the jugular bulb. Four patients who underwent surgery via the transcondylar approach to treat dural arteriovenous fistulas around the jugular foramen were retrospectively reviewed. Previously, endovascular treatment was attempted in all patients. The success of the surgical treatment was examined with postoperative angiography. Complete obliteration of the dural arteriovenous fistulas (DAVFs) was achieved in three patients, and significant flow reduction in one individual. All patients had a good postoperative outcome, and only one experienced mild hypoglossal nerve palsy. Despite extensive bone drilling, an occipitocervical fusion was necessary in only one patient with bilateral lesions. The use of an individually tailored transcondylar approach to treat dural arteriovenous fistulas at the region of the jugular foramen is most effective. This approach allows for complete obliteration of the connecting arterial feeders, and removal of bony structures containing pathological vessels. more...
- Published
- 2007
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196. Clinical impact of CCM mutation detection in familial cavernous angioma.
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Sürücü O, Sure U, Gaetzner S, Stahl S, Benes L, Bertalanffy H, and Felbor U
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- Brain Neoplasms pathology, Brain Neoplasms surgery, Child, Preschool, DNA Mutational Analysis, Female, Hemangioma, Cavernous pathology, Hemangioma, Cavernous surgery, Humans, KRIT1 Protein, Magnetic Resonance Imaging methods, Male, Brain Neoplasms genetics, Family Health, Hemangioma, Cavernous genetics, Microtubule-Associated Proteins genetics, Mutation, Proto-Oncogene Proteins genetics
- Abstract
Introduction and Background: A 3-year-old Bosnian girl with a large symptomatic brainstem and multiple supratentorial cavernous angiomas, who underwent neurosurgical treatment, is presented. As multiple cavernomas are more common in familial cases, genetic analyses and neuroradiological imaging were performed in the patient and her parents to see whether there was any evidence for inheritance. This information is important for genetic counseling and provision of medical care for at-risk relatives. Currently, no recommendation is available on how to manage these cases., Results: Genetic analyses demonstrated a novel CCM1 frameshift mutation (c.1683_1684insA; p.V562SfsX6) in the child and the asymptomatic 27-year-old mother. Sensitive gradient-echo magnetic resonance imaging of the mother revealed multiple supratentorial lesions, whereas analogous imaging of the father showed no pathological findings., Conclusion: This case exemplifies that seemingly sporadic cases with multiple lesions might well be hereditary and that presymptomatic genetic testing of family members may identify relatives for whom clinical and neuroradiological monitoring is indicated. more...
- Published
- 2006
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197. Image-guided ultrasonography for recurrent cystic gliomas.
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Enchev Y, Bozinov O, Miller D, Tirakotai W, Heinze S, Benes L, Bertalanffy H, and Sure U
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- Brain Neoplasms diagnostic imaging, Brain Neoplasms pathology, Glioma diagnostic imaging, Glioma pathology, Humans, Neoplasm Recurrence, Local diagnostic imaging, Neoplasm Recurrence, Local pathology, Retrospective Studies, Treatment Outcome, Brain Neoplasms surgery, Echoencephalography, Glioma surgery, Neoplasm Recurrence, Local surgery, Neuronavigation methods, Surgery, Computer-Assisted methods
- Abstract
Background: Long-term survival of patients with recurrent gliomas depends on the extent of resection. Thus, the desirability of an intra-operative imaging modality that can augment the resection extension without affecting vital surrounding structures is more than obvious. It was the aim of the present study to evaluate a possible benefit of image-guided intra-operative ultrasonography for the surgery of recurrent gliomas., Method: The authors performed ultrasonography-assisted image-guided resection of recurrent gliomas in 16 patients. An ultrasound device (IGSonic) was integrated into the VectorVision2 navigation system (BrainLAB, Heimstetten, Germany). The IGSonic Probe 10V5 was connected to the VectorVision Navigation station via an IGSonic Device Box. Following patient registration, MRI based neuronavigation was used to determine the skin incision and the bone flap. Before opening the dura, the underlying structures were explored by ultrasound combined with the corresponding MR images. The navigated ultrasound displayed the sonographic image of the intracranial anatomy on the navigation screen in a composed overlay fashion., Findings: The integration of intra-operative ultrasound into neuronavigation system offered quick and helpful intra-operative images in all 16 procedures. Due to the specific ultrasonic characteristics of the solid and the cystic parts, our technique created highly useful images in 10 patients with cystic recurrences. In these, user friendly images were obtained that were easy to understand even for neurosurgeons without major experience in intra-operative ultrasound., Conclusions: Neurosonography is a time- and cost-effective technology offering intra-operative imaging. The improved orientation and visualization of tumour remnants, adjacent ventricles, and the enhanced intra- and peri-tumoural vasculature is one of the main advantages of ultrasonography-assisted image-guided surgery, which is most obvious during surgery for cystic gliomas. more...
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- 2006
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198. Treatment of a partially thrombosed giant aneurysm of the vertebral artery by aneurysm trapping and direct vertebral artery-posterior inferior cerebellar artery end-to-end anastomosis: technical case report.
- Author
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Benes L, Kappus C, Sure U, and Bertalanffy H
- Subjects
- Aged, Brain Stem blood supply, Brain Stem pathology, Brain Stem surgery, Cerebellum blood supply, Cerebral Angiography, Cerebral Arterial Diseases diagnostic imaging, Cerebral Arterial Diseases physiopathology, Cranial Fossa, Posterior anatomy & histology, Cranial Fossa, Posterior pathology, Cranial Fossa, Posterior surgery, Cranial Nerves anatomy & histology, Cranial Nerves surgery, Craniotomy methods, Decompression, Surgical methods, Female, Humans, Intracranial Aneurysm diagnostic imaging, Intracranial Aneurysm physiopathology, Magnetic Resonance Imaging, Occipital Bone pathology, Occipital Bone surgery, Prostheses and Implants standards, Tomography, X-Ray Computed, Treatment Outcome, Vertebral Artery diagnostic imaging, Vertebral Artery pathology, Cerebral Arterial Diseases surgery, Embolization, Therapeutic methods, Intracranial Aneurysm surgery, Neurosurgical Procedures methods, Vascular Surgical Procedures methods, Vertebral Artery surgery
- Abstract
Objective: The purpose of this article is to focus for the first time on the operative management of a direct vertebral artery (VA)-posterior inferior cerebellar artery (PICA) end-to-end anastomosis in a partially thrombosed giant VA-PICA-complex aneurysm and to underline its usefulness as an additional treatment option., Methods: The operative technique of a direct VA-PICA end-to-end anatomosis is described in detail. The VA was entering the large aneurysm sack. Distally, the PICA originated from the aneurysm sack-VA-complex. The donor and recipient vessel were cut close to the aneurysm. Whereas the VA was cut in a straight manner, the PICA was cut at an oblique 45-degree angle to enlarge the vascular end diameter. Vessel ends were flushed with heparinized saline and sutured. The thrombotic material inside the aneurysm sack was removed and the distal VA clipped, leaving the anterior spinal artery and brainstem perforators free., Results: The patient regained consciousness without additional morbidity. Magnetic resonance imaging scans revealed a completely decompressed brainstem without infarction. The postoperative angiograms demonstrated a good filling of the anastomosed PICA., Conclusion: Despite the caliber mistmatch of these two vessels the direct VA-PICA end-to-end anastomosis provides an accurate alternative in addition to other anastomoses and bypass techniques, when donor and recipient vessels are suitable and medullary perforators do not have to be disrupted. more...
- Published
- 2006
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199. Two novel cell specific receptor proteins, CRLR and CD 117 in human glial tumors.
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Mennel HD, Hallier-Neelsen M, Hagner S, and Benes L
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- Actins metabolism, Brain Neoplasms blood supply, Brain Neoplasms pathology, Calcitonin Receptor-Like Protein, Endothelium, Vascular metabolism, Glial Fibrillary Acidic Protein metabolism, Glioma blood supply, Glioma pathology, Humans, Muscle, Smooth, Vascular metabolism, Brain Neoplasms metabolism, Glioma metabolism, Proto-Oncogene Proteins c-kit metabolism, Receptors, Calcitonin metabolism
- Abstract
Objective: CRLR (calcitonin receptor-like receptor) and CD 117, the gene product of c-kit have been shown to be expressed in cells of glial tumors, especially in those with higher malignancy. Here we report the distribution of these peptides in various cellular compartments within those tumors., Material: Both receptor proteins have been investigated in 95 glial tumor biopsies of different grades., Methods: Both proteins were visualized by immunohistochemistry with antibodies either commercially available or raised for this purpose., Results: Both receptor peptides can be identified in or around tumor blood vessels. CRLR occurs in some endothelial cells, especially in the microvascular proliferations of glioblastoma multiforme, whereas CD 117 preferentially occurs in cells of the thickened vascular wall within cells of pericyte or fibroblast morphology. Both antigens are found in addition in few neoplastic cells of overt astrocyte morphology., Conclusions: The occurrence of identical antigens in glial tumor blood vessels and in neighboring tumor cells underlines the common origin of "mesenchymal" and "neuroepithelial" components of such (malignant) glial neoplasms. more...
- Published
- 2006
200. A novel platform for image-guided ultrasound.
- Author
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Tirakotai W, Miller D, Heinze S, Benes L, Bertalanffy H, and Sure U
- Subjects
- Brain surgery, Brain Neoplasms diagnostic imaging, Brain Neoplasms surgery, Humans, Neuronavigation methods, Surgery, Computer-Assisted methods, Surgical Equipment, Ultrasonography methods, Neuronavigation instrumentation, Surgery, Computer-Assisted instrumentation, Ultrasonography instrumentation
- Abstract
Objective: The combination of classic neuronavigation and intraoperative ultrasound is a recent innovation in image guidance technology. However, this technique requires two hardware components (neuronavigation and an ultrasound system). It was the aim of the study to describe a new simplified technology of a so-called one-platform navigation system developed by our institution in collaboration with the industry and to demonstrate its range of various applications., Methods: An ultrasound device (IGSonic; BrainLAB, Munich, Germany) is integrated into the VectorVision2 navigation system (BrainLAB, Munich, Germany). The IGSonic Probe 10V5 is connected to the VectorVision Navigation station via an IGSonic Device Box. Once the ultrasound probe is calibrated, the navigated ultrasound displays the sonographic image of the intracranial anatomy on the navigation screen in a composed overlay fashion. It might depict vascular structures within the ultrasound plane by a duplex mode. Ultrasound can also be operated independently from navigation., Results: The VectorVision2 system combines intraoperative ultrasound data sets with preoperatively acquired neuronavigation data sets in plug and play fashion. The system provides a cost-effective intraoperative imaging modality that offers a good anatomic orientation by various composite images, including the display of the amount of brain shift. In our institution, the comprehensible interface led to a routine use of the technology by several neurosurgeons who had not been familiar with the ultrasound technology before., Conclusion: The integration of an ultrasound device into an existing navigation system has been successfully developed. The system offers a friendly user interface and cost-effective intraoperative imaging feedback. Although brain shift can be visualized by an image overlay technology as demonstrated by the present system, future developments should aim at fusion techniques of both intra- and preoperative image data sets. more...
- Published
- 2006
- Full Text
- View/download PDF
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