251 results match your criteria EEG Triphasic Waves


Do Triphasic Waves and Nonconvulsive Status Epilepticus Arise From Similar Mechanisms? A Computational Model.

J Clin Neurophysiol 2021 Jun 18. Epub 2021 Jun 18.

Department of Technical Medicine, University of Twente, Enschede, the Netherlands; Department of Applied Mathematics, University of Twente, Enschede, the Netherlands; Northwest University, Xi'an, China; and Department of Neurology, Massachusetts General Hospital, Boston, Massachusetts, U.S.A.

Purpose: Triphasic waves arising in patients with toxic metabolic encephalopathy (TME) are often considered different from generalized periodic discharges (GPDs) in patients with generalized nonconvulsive status epilepticus (GNCSE). The primary objective of this study was to investigate whether a common mechanism can explain key aspects of both triphasic waves in TME and GPDs in GNCSE.

Method: A neural mass model was used for the simulation of EEG patterns in patients with acute hepatic encephalopathy, a common etiology of TME. Read More

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Can We Distinguish TWs From Other GPDs? Do We Need to?

Authors:
Brandon Foreman

J Clin Neurophysiol 2021 Jun 18. Epub 2021 Jun 18.

Department of Neurology & Rehabilitation Medicine, University of Cincinnati, Cincinnati, Ohio, U.S.A.

Summary: Triphasic waves are intuitively distinctive waveforms that fall under the umbrella of generalized periodic discharges. The ability to distinguish these waveforms consistently could be helpful if a specific underlying pathophysiology could be identified. However, scalp EEG and clinical observation have been limited in their ability to elucidate the underlying cortical physiology that leads to triphasic waves. Read More

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Atypical or Typical Triphasic Waves-Is There a Difference? A Review.

J Clin Neurophysiol 2021 Jun 18. Epub 2021 Jun 18.

Clinical Neurophysiology Department, Marqués de Valdecilla University Hospital, Santander, Cantabria, Spain; Biomedical Research Institute (IDIVAL), Santander, Cantabria, Spain; and Department of Neurology, Johns Hopkins Bayview Medical Center, Baltimore, Maryland, U.S.A.

Summary: The entity of triphasic waves (TWs) and TW encephalopathy has derived from the subjective art of EEG interpretation. Indeed, there are few if any guidelines regarding many different aspects of TWs. The authors seek to shed light on the nature and the diagnostic characteristics of various types of TWs, differentiating "typical" from "atypical" forms. Read More

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Status Triphasicus Versus Status Epilepticus?

J Clin Neurophysiol 2021 Jun 18. Epub 2021 Jun 18.

Department of Neurology, Miller School of Medicine, University of Miami, Miami, Florida, U.S.A.; and Neurology Services, University of Miami Hospital and Clinics and Jackson Memorial Hospital, Miami, Florida, U.S.A.

Summary: Generalized periodic patterns with triphasic wave morphology, long referred to as triphasic waves [TWs], had been associated with metabolic encephalopathies, although other neurologic and systemic causes have since been identified. In a recent classification of periodic patterns, TWs were formally grouped with the generalized periodic discharges, which are often associated with ictal activity. The interpretation of generalized periodic patterns with TWs as nonictal can have significant implications in the management of comatose patients in nonconvulsive status epilepticus. Read More

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Triphasic Waves: Historical Overview of an Unresolved Mystery.

J Clin Neurophysiol 2021 Jun 18. Epub 2021 Jun 18.

Clinical Neurophysiology Department, Marqués de Valdecilla University Hospital, Santander, Cantabria, Spain; Biomedical Research Institute (IDIVAL), Santander, Cantabria, Spain; and Department of Neurology, Johns Hopkins Bayview Medical Center, Baltimore, Maryland, U.S.A.

Summary: Triphasic waves are a fascinating and mysterious EEG feature. We now have to accept that, at times, epileptiform discharges may have a blunted "triphasic morphology," and that there may be great difficulty in distinguishing between these often similar forms. The aim of this review was to describe the evolution in our understanding of triphasic waves that has occurred regarding the pathophysiology of triphasic waves, their most frequent causes, and the diagnostic difficulties involved in interpretation and differentiation from nonconvulsive status epilepticus. Read More

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White Matter Disease-The True Source of Triphasic Waves?

J Clin Neurophysiol 2021 Jun 18. Epub 2021 Jun 18.

Department of Neurology, Johns Hopkins Bayview Medical Center, Baltimore, Maryland, U.S.A.; and Department of Neurology, Memorial Sloan Kettering Cancer Center, New York, New York, U.S.A.

Summary: Triphasic waves are EEG phenomena typically seen in patients with acute encephalopathy and have importance in diagnosis and prognosis in these cases. The underlying metabolic disturbances associated with their incidence have been described previously, but neuroimaging characteristics are not well delineated. There are a few small studies that define neuroimaging results in patients with triphasic waves. Read More

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Lateralized Periodic Discharges: Which patterns are interictal, ictal, or peri-ictal?

Clin Neurophysiol 2021 Jul 27;132(7):1593-1603. Epub 2021 Apr 27.

Epilepsy and EEG Unit, Johns Hopkins Bayview Medical Center, Baltimore, MD, USA.

There is an ongoing debate if Lateralized Periodic Discharges (LPDs) represent an interictal pattern reflecting non-specific but irritative brain injury, or conversely, is an ictal pattern. The challenge is: how to correctly manage these patients? Between this apparent dichotomous distinction, there is a pattern lying along the interictal-ictal continuum (IIC) that we may call "peri-ictal". Peri-ictal means that LPDs are temporally associated with epileptic seizures (although not necessarily in the same recording). Read More

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Are Triphasic Waves Different From Generalized Spike-Wave Discharges?

J Clin Neurophysiol 2021 Apr 7. Epub 2021 Apr 7.

Department of Neurology, Johns Hopkins University; Baltimore, Maryland, U.S.A.; and Department of Neurology, Johns Hopkins Bayview Medical Center, Baltimore, Maryland, U.S.A.

Summary: Generalized periodic discharges with triphasic morphology were previously referred to as triphasic waves but have now been subsumed into the ACNS classification as generalized periodic discharges. Although triphasic waves and generalized spike-wave complexes may resemble each other and hence may be incorrectly identified in comatose critically ill patients, many authors believe that there are different entities, with definable morphologic and clinical differences attributable to each waveform. The occurrence of both patterns in the same patient is extremely rare with only a single prior case report. Read More

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Electroencephalography of mechanically ventilated patients at high risk of delirium.

Acta Neurol Scand 2021 May 5. Epub 2021 May 5.

Department of Intensive Care Medicine, University Hospital (CHUV) and University of Lausanne, Lausanne, Switzerland.

Objective: Neurophysiological exploration of ICU delirium is limited. Here, we examined EEG characteristics of medical-surgical critically ill patients with new-onset altered consciousness state at high risk for ICU delirium.

Materials And Methods: Pre-planned analysis of non-neurological mechanically ventilated medical-surgical ICU subjects, who underwent a prospective multicenter randomized, controlled EEG study (NCT03129438, April 2017-November 2018). Read More

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Creutzfeldt-Jakob and Vascular Brain Diseases: Their Overlap and Relationships.

Front Neurol 2021 25;12:613991. Epub 2021 Feb 25.

Department of Neurology, Kaplan Medical Center, Rehovot, Israel.

Only a few case reports of stroke-like onset of Creutzfeldt-Jakob disease (CJD) have previously been published. We aimed to analyze the neurological, imaging, electroencephalographic (EEG), and laboratory features of patients with this very rare phenomenon. Here, we review the clinical characteristics, onset features, and clinical course variants of stroke-like CJD in 23 such patients. Read More

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February 2021

New Onset Non-Convulsive Status Epilepticus Despite Cefepime Renal Dose Adjustment.

Cureus 2021 Jan 13;13(1):e12689. Epub 2021 Jan 13.

Neurology, SSM Health St. Mary's Hospital, St. Louis, USA.

Cefepime, a widely used fourth-generation cephalosporin for coverage of both gram-positive and gram-negative bacteria, has been reported to have associated neurological adverse effects. These effects have been seen mostly in patients mostly with impaired renal function, and currently, dosing is based on creatinine clearance to reduce its toxic effect profile. Despite renal dose adjustment, we present a case of a 40-year-old woman who was managed for bacteremia, acute kidney injury, and hemorrhagic shock. Read More

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January 2021

Source Analysis of Triphasic Waves Using Quantitative Neuroimaging.

J Clin Neurophysiol 2020 Dec 23;Publish Ahead of Print. Epub 2020 Dec 23.

Departamento de Neurologia, Psicologia e Psiquiatria, Faculdade de Medicina de Botucatu (UNESP), Botucatu, Brazil.

Purpose: Triphasic waves (TWs), a common EEG pattern, are considered a subtype of generalized periodic discharges. Most patients with TWs present with an altered level of consciousness, and the TW pattern is believed to represent thalamocortical dysfunction. However, the exact meaning and mechanism of TWs remain unclear. Read More

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December 2020

Source Imaging of Triphasic Waves and Other Encephalopathies.

J Clin Neurophysiol 2020 Dec 1. Epub 2020 Dec 1.

Department of Neurology, Johns Hopkins University, Baltimore, Maryland, U.S.A.

Purpose: Triphasic waves (TWs) are defined as high-amplitude positive waveforms with preceding and after-going negative waves, typically seen in medically ill patients. TWs manifest in similar clinical presentations as other EEG encephalopathies; however, electrographically, they appear different. To better understand the difference, the authors used two different source localization software programs to find a reproducible and unique signature for TW. Read More

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December 2020

Acute Toxicity and Triphasic Waves-The Example of Cefepime.

J Clin Neurophysiol 2020 Oct 20. Epub 2020 Oct 20.

Department of Neurology, Johns Hopkins University, Baltimore, Maryland, U.S.A.

Purpose: Triphasic waves (TWs) have been associated with a host of medication toxicities, and cefepime has emerged recently as a frequently encountered offending agent. This investigation aims to evaluate cefepime-induced encephalopathy and to report the associated clinical, EEG expression with TWs, and the radiologic findings.

Methods: A retrospective multicenter observational study examining adult patients with cefepime-induced encephalopathy with generalized periodic discharges on either routine or continuous EEG between January 2014 and January 2020. Read More

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October 2020

In the Kingdom of Triphasic Waves, White Matter Is the Eminence Grise.

J Clin Neurophysiol 2020 Sep 14. Epub 2020 Sep 14.

Department of Neurology, Johns Hopkins Bayview Medical Center, Baltimore, Maryland, U.S.A. Dr. Kotchetkov is now with the Department of Neurology, Memorial Sloan Kettering Cancer Center, New York, New York, U.S.A.

Purpose: Triphasic waves (TWs) have been associated with multiple conditions and adverse outcomes. This study explores the role of white matter disease (WMD) in the generation of TWs when other common causes associated with these discharges are absent.

Methods: This is a retrospective case series performed at Johns Hopkins Bayview Medical Center from January 2016 to May 2018, which screened for patients with severe WMD, who had TWs on EEG without the presence of commonly cited provoking factors, including (1) hepatic disease; (2) severe uremia over baseline; (3) the drugs cefepime, ifosfamide, lithium, and baclofen; or (4) global hypoxic-ischemic injury. Read More

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September 2020

Triphasic waves in electroencephalogram as a possible early marker of carcinomatous meningitis: a case report.

Medicine (Baltimore) 2020 Aug;99(33):e21735

Department of Neurology and Neuroscience Center.

Rationale: Carcinomatous meningitis is a rare neurological complication. This condition is difficult to diagnose, and misdiagnosis is common because the clinical manifestations are variable. Cerebrospinal fluid (CSF) cytology is the gold standard for diagnosis. Read More

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Triphasic Waves Are Generated by Widespread Bilateral Cortical Networks.

J Clin Neurophysiol 2021 Jun 18. Epub 2021 Jun 18.

Departments of Clinical Neurophysiology and Clinical Medicine, Aarhus University, Aarhus, Denmark; Department of Clinical Neurophysiology, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark; Department of Neurology, Aarhus University Hospital, Aarhus, Denmark; Department of Neurology, Johns Hopkins Bayview Medical Center, Baltimore, Maryland, U.S.A.; and Department of Clinical Neurophysiology, Danish Epilepsy Centre, Dianalund, Denmark.

Purpose: Triphasic waves (TWs) have been observed in the EEG recorded in patients with various types of encephalopathy, yet their genesis and significance is still debated. The aim of this study was to elucidate the localization of the cortical generators of TWs using EEG source imaging.

Methods: In 20 consecutive patients who had encephalopathy with TWs, EEG source imaging of the first negative and the positive phases of the TW was performed. Read More

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[ANTIBIOTIC-ASSOCIATED ENCEPHALOPATHY].

Harefuah 2020 May;159(5):364-369

Department of Medicine A, Laniado Hospital, Sanz Medical Center, Netanya.

Introduction: Antibiotic-associated encephalopathy (AAE) is a relatively uncommon adverse drug event, mostly encountered in hospitalized patients undergoing intravenous antibiotic treatment. A typical case is reported and the literature is reviewed. Most antibiotic drugs have been implicated in the pathogenesis. Read More

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Generalized Periodic Discharges With Triphasic Morphology in the Setting of Aztreonam Neurotoxicity.

Clin EEG Neurosci 2021 Jan 13;52(1):66-68. Epub 2020 May 13.

Johns Hopkins Bayview Medical Center, Johns Hopkins University School of Medicine, Baltimore, MD, USA.

Generalized periodic discharges with triphasic morphology (GPDs + TWm) have been reported with multiple metabolic and drug toxicities. Beta-lactam antibiotics in some cases can cause neurotoxicity with GPDs + TWm on EEG. There are no reports in the literature of aztreonam causing neurotoxicity and GPDs + TWm. Read More

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January 2021

Clinical characteristics and epilepsy in genomic imprinting disorders: Angelman syndrome and Prader-Willi syndrome.

Ci Ji Yi Xue Za Zhi 2020 Apr-Jun;32(2):137-144. Epub 2019 Oct 31.

Department of Pediatrics, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei, Taiwan.

Angelman syndrome (AS) and Prader-Willi syndrome (PWS) are considered sister imprinting disorders. Although both AS and PWS congenital neurodevelopmental disorders have chromosome 15q11.3-q13 dysfunction, their molecular mechanisms differ owing to genomic imprinting, which results in different parent-of-the-origin gene expressions. Read More

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October 2019

Clinical and Radiological Correlates of Different Electroencephalographic Pattern in Hospitalized Patients.

Authors:
Saima Nazish

Clin EEG Neurosci 2021 Jul 6;52(4):280-286. Epub 2020 Mar 6.

Department of Neurology, College of Medicine, 48135Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia.

. The present study aimed to determine the clinical and radiological correlates of different electroencephalographic (EEG) patterns in hospitalized patients. . Read More

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A novel neural computational model of generalized periodic discharges in acute hepatic encephalopathy.

J Comput Neurosci 2019 12 11;47(2-3):109-124. Epub 2019 Sep 11.

The Department of Neurology, Massachusetts General Hospital, Boston, MA, USA.

Acute hepatic encephalopathy (AHE) due to acute liver failure is a common form of delirium, a state of confusion, impaired attention, and decreased arousal. The electroencephalogram (EEG) in AHE often exhibits a striking abnormal pattern of brain activity, which epileptiform discharges repeat in a regular repeating pattern. This pattern is known as generalized periodic discharges, or triphasic-waves (TPWs). Read More

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December 2019

Clinical EEG slowing correlates with delirium severity and predicts poor clinical outcomes.

Neurology 2019 09 29;93(13):e1260-e1271. Epub 2019 Aug 29.

From the Department of Neurology (E.Y.K., A.N., W.W., A.R.S., S.L.R., G.G., D.G., M.B.W.) and Clinical Data Animation Center (M.B.W.), Massachusetts General Hospital, Boston.

Objective: To determine which findings on routine clinical EEGs correlate with delirium severity across various presentations and to determine whether EEG findings independently predict important clinical outcomes.

Methods: We prospectively studied a cohort of nonintubated inpatients undergoing EEG for evaluation of altered mental status. Patients were assessed for delirium within 1 hour of EEG with the 3-Minute Diagnostic Interview for Confusion Assessment Method (3D-CAM) and 3D-CAM severity score. Read More

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September 2019

Clinical neurophysiology of altered states of consciousness: Encephalopathy and coma.

Handb Clin Neurol 2019 ;161:73-88

Department of Neurology, Johns Hopkins Hospital, Baltimore, MD, United States. Electronic address:

The neurophysiologist will commonly encounter patients with encephalopathy/delirium (altered consciousness with impaired cognition, usually with sleep-wake cycle alteration and lethargy) or coma (an eyes-closed state of unresponsiveness) in the hospital setting. Assessing the background frequency of the EEG, as well as the presence or absence of other features (reactivity, periodic discharges such as triphasic waves), can provide insight into the patient's underlying condition and in some cases may provide prognostic information. The literature of postanoxic arrest EEG patterns continues to expand. Read More

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January 2020

Cephalosporin-related neurotoxicity: Metabolic encephalopathy or non-convulsive status epilepticus?

J Clin Neurosci 2019 Sep 11;67:163-166. Epub 2019 Jun 11.

Royal Perth Hospital, Department of Neurology, Perth, Western Australia, Australia; Western Australian Adult Epilepsy Service, Perth, Western Australia, Australia; University of Western Australia, Faculty of Medicine, Perth, Western Australia, Australia.

Metabolic encephalopathy and Non-Convulsive Status Epilepticus (NCSE) have been reported with cephalosporin use, particularly cefepime. We aimed to analyze the clinical and EEG findings in patients with cephalosporin-related neurotoxicity (CRN) at our hospital identified via the hospital EEG database, and to critically review CRN case reports in the literature. A Medline search was performed to identify CRN cases where a representative sample of EEG was provided. Read More

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September 2019

Young-onset sporadic Creutzfeldt-Jakob disease with atypical phenotypic features: a case report.

J Med Case Rep 2019 May 29;13(1):163. Epub 2019 May 29.

Department of Neurology, Bangur Institute of Neurosciences, IPGMER and SSKM Hospital, Kolkata, West Bengal, 700025, India.

Background: Sporadic Creutzfeldt-Jakob disease, with a mean survival of 6 months, is duly considered among the most fatal neurological disorders. Rapidly progressive dementia with multi-axial involvement of the nervous system is the known presentation. Although, the peak age at onset is between sixth and eighth decades, cases of young-onset sporadic Creutzfeldt-Jakob disease have also been reported in the literature. Read More

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Clinical features and genetic characteristics of two Chinese pedigrees with fatal family insomnia.

Prion 2019 01;13(1):116-123

b National Clinical Research Center for Geriatric Disorders , Changsha , Hunan , China.

: Fatal familial insomnia (FFI) is a rare autosomal-dominant inherited prion disease characterized clinically by severe sleep disorder, motor signs, dysautonomia and abnormal behaviour. FFI is caused by a missense mutation at codon 178 of the prion protein gene (PRNP). Our study is aimed to explore typical clinical and genetic features of two Chinese pedigrees with FFI and review the related literatures. Read More

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January 2019

Atypical Interictal Epileptiform Discharges in Electroencephalography.

J Epilepsy Res 2018 Dec 31;8(2):55-60. Epub 2018 Dec 31.

King Khalid Hospital (KKH), Hail, Saudi Arabia.

Background And Purpose: A great deal of attention has been focused on "typical" interictal epileptiform discharges (IEDs) in the electroencephalography (EEG) literature. However, there is a paucity of data on "atypical" IEDs, namely, positive sharp waves (PSWs), focal triphasic sharp waves and spikes (FTSWs), sharp slow waves (SSWs), bifid spikes, and "notched" delta. In this present study, we sought to address the pathophysiology, characteristics, and diagnostic significance of "atypical" IEDs in clinical neuroscience. Read More

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December 2018

Encephalopathy Induced by High Plasma and Cerebrospinal Fluid Ceftriaxone Concentrations in a Hemodialysis Patient.

Intern Med 2019 Jun 25;58(12):1775-1779. Epub 2019 Feb 25.

Department of Nephrology, Tokyo Medical and Dental University, Japan.

Encephalopathy is a rare side effect of cephalosporin treatment. We herein present a case of encephalopathy induced by ceftriaxone, a third-generation cephalosporin, in a patient with renal failure. An 86-year-old woman on maintenance hemodialysis received ceftriaxone for Helicobacter cinaedi bacteremia. Read More

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