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EEG recording of a 61-year-old woman in a coma state, after termination of a generalized tonic-clonic seizure. The EEG reveals continuous epileptiform discharges—sharp waves—over both right and left hemispheres, which in association with the clinical picture constitute a nonconvulsive status epilepticus. The patient was classified into Ictal group. https://doi.org/10.1371/journal.pone.0184050.g004
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Introduction:
Nonconvulsive seizures (NCS) are frequent in hospitalized patients and may further aggravate injury in the already damaged brain, potentially worsening outcomes in encephalopathic patients. Therefore, both early seizure recognition and treatment have been advocated to prevent further neurological damage.
Objective:
Evaluate the mai...
Citations
... The voltage was divided into three groups of 'Normal' (greater than or equal to 20 μV), 'Low' (below 20 μV and greater than two μV), and 'Isoelectric' (equal or less than two μV; i.e., electrocerebral shutdown). Paroxysmal EEG activities were also recorded, including electrographic seizures and periodic or rhythmic patterns (16). CT scans of patients were scored based on the Rotterdam scoring system: Basal cistern state (normal 0, compact 1, and absent 2), midline shift (no midline shift or less than 5 mm: 0 points, greater than 5 mm: 1 point), Epidural lesion (absent 0, present 1), and ventricular or subarachnoid hemorrhage (absent 0, present 1). ...
Background: Head injury is a silent epidemic in developed countries and is one of the leading causes of death and disability. Determining the precise and early prognosis of head injury, especially in severe cases, is essential and will help define treatment actions and rehabilitation plans and counsel other family members. The purpose of this study was to determine the relationship between electroencephalographic findings and prognosis in patients with decreased levels of consciousness due to head injury. Methods: This is a retrospective descriptive-analytical study on patients with reduced levels of consciousness due to head injury, referred to Tir Hospital (Tehran) in the first half of 2018. Overall, 52 patients were studied and divided according to their GCS into two groups: favorable prognosis (30 patients, 57.7%) and poor prognosis (22 patients, 42.3%). We tried to find the relation between EEG findings such as voltage, electrographic seizures, periodic and rhythmic patterns, and the prognosis. Results: Normal voltage was associated with a favorable prognosis, with a high specificity (95%) and a less robust sensitivity (63%). The isoelectric voltage (electrocerebral shutdown) was associated with a poor prognosis. Normal and isoelectric voltages were good predictors with 95% and 100% Positive Predictive Values (PPV), respectively. There was a statistically significant relationship between EEG frequency range and prognosis. Conclusion: This study showed that EEG parameters might provide valuable data regarding the prognosis of decreased consciousness of patients with a head injury, also for the guidance of physicians and informing the patients’ family.
... 31 However, Maingueneau et al 32 are of view that PDs are simply markers of nonspecific brain injury that are often accompanied by underlying comorbidities. In the study conducted by Sanches et al, 33 treatment with AED or intravenous anesthetic drugs did not improve the incidence of unfavorable outcomes in patients with acute ALC and abnormal routine EEG, regardless of the presence of rhythmic, periodic, or ictal electroencephalogram patterns. In this study, asymmetrical background was associated with TBI, while persistent focal SWA, asymmetric background, and RDA were statistically significantly more prevalent in patients discharged from hospital due to sequelae of current illnesses. ...
Abstract
Objective. The objective of this study was to determine the frequency and clinical correlates of different electroencephalographic
patterns and their association with clinical outcomes in critically ill patients. Subjects and Methods. This retrospective crosssectional
study was performed in the Neurology Department of King Fahd Hospital of the University, Kingdom of Saudi
Arabia and involved a review and analysis of medical records pertaining to 179 intensive care unit patients who underwent
electroencephalography (EEG) in the June to November 2018 period. Results. Among the different etiologies, presence of
spike and wave or sharp wave (SWs) was associated with encephalitis (P = .01) and large artery stroke (P = .01), whereas
markedly attenuated EEG activity (p = .04) and burst suppression (P = .01) were associated with large artery stroke and
hypoxic ischemic encephalopathy (HIE), respectively. Generalized theta activity (P = .01) was significantly found in patients
of septic encephalopathy, while generalized delta activity (P = .02) and asymmetrical background (P = .04) were significantly
associated with traumatic brain injury. Presence of periodic discharges in EEG was significantly associated with more
adverse clinical outcomes (P = .001), whereas rhythmic delta activity (RDA) (P = .03), persistent focal slow wave activity
(P = .01), and asymmetric background (P = .002) were found in patients who were discharged from hospital with sequelae of
current illness. Conclusion. Certain EEG patterns are associated with particular underlying etiologies like SWs for encephalitis,
markedly attenuated EEG activity and burst suppression with large artery stroke and HIE, respectively. Whereas few EEG
patterns, including periodic discharges, RDA, persistent focal slow wave activity have some prognostic value in critically ill
patients. However, they cannot be used as markers for prognostic assessment of patients without considering other clinical
and diagnostic variables. Further larger prospective studies with continuous EEG monitoring with control of confounding
factors are needed.
Traumatic Brain Injury (TBI) or also known as a head injury is one of the leading causes of death among young people and is also one of the health problems defined as impact, penetration, and rapid movement of the brain within the skull that can result in changes in mental status and is often referred to as the silent epidemic.
Head injuries can also result in electrophysiological abnormalities seen on electroencephalography (EEG) recordings. Electroencephalography was the first clinical neurodiagnostic assessment to reveal abnormal brain function after a head injury. For detecting brain injury, EEG may be more sensitive than clinical neurologic examination.
In general conditions, electroencephalography is performed on patients with moderate to severe head injuries to provide information about the severity of the head injury, and establish a diagnosis of non-convulsive status epilepticus. This diagnosis often follows head injuries because patients with loss of consciousness are difficult to identify without an EEG examination. This also helps determine a prognosis for recovery and the likelihood of post-traumatic seizures.
Electroencephalography features in head injuries depend on the severity of the injury and the location of the head itself. Electroencephalography after head injury shows slowing of the posterior dominant rhythm and increasing diffuse theta slowing, which returns to normal within hours or may subside more slowly over several weeks. Electroencephalography changes are not the same in each individual, due to differences in the severity of head injuries. It is important to know that there is no clear or specific EEG for mild traumatic brain injury.
HSVE (Herpes simplex virus encephalitis) is an infection caused by herpes simplex virus type 1 (HSV-1) or type 2 that produces neurologic problems. HSVE is associated with significant morbidity and mortality in adults even with antiviral medication, and it is a fatal disease in babies and children regardless of treatment. The most likely pathways include retrograde transmission through the olfactory or trigeminal nerves, as well as hematogenous spread. The most common presenting symptoms are encephalopathy, fever, convulsions, headache, and regional neurologic dysfunction. An accurate history and physical examination are required to identify Herpes simplex virus encephalitis (HSVE), and a prompt assessment is advised after the diagnosis has been established. HSVE is a neurodegenerative disease that may be fatal. Rapid diagnostic work-up and early diagnosis in all suspected or confirmed cases will result in early initiation of intravenous acyclovir, which may decrease morbidity and death.
