seizure – qEEGsupport.com

Electroencephalography (EEG) Underused Investigative Tool in Hospitals, Study Finds

A retrospective study of patients who had in-hospital electroencephalography (EEG) has established that EEG is a valuable tool that could be deployed more widely to identify treatable causes of impaired consciousness in the hospital setting.

The study is published in the April issue of the Mayo Clinic Proceedings.

Altered mental status (AMS) and paroxysmal spells of uncertain origin are common among hospitalized patients. Impaired consciousness can sometimes be linked to metabolic or cardiac causes, but some of these spells may represent seizures or non-convulsive epilepsy, which can be detected only by electroencephalography (EEG). Although EEG is the key test in making these diagnoses, it is relatively underused in the inpatient setting owing to lack of availability and neurologic consultation at many hospitals in the United States.

Electroencephalographic Cerebral Dysrhythmic Abnormalities in the Trinity of Nonepileptic General Population, Neuropsychiatric, and Neurobehavioral Disorders

Subclinical electroencephalographic epileptiform discharges in neurobehavioral disorders are not uncommon. The clinical significance and behavioral, diagnostic, and therapeutic implications of this EEG cerebral dysrhythmia have not been fully examined. Currently the only connotation for distinctive epileptiform electroencephalographic patterns is epileptic seizures. Given the prevailing dogma of not treating EEGs, these potential aberrations are either disregarded as irrelevant or are misattributed to indicate epilepsy. This article reappraises the literature on paroxysmal EEG dysrhythmia in normative studies of the healthy nonepileptic general populations, neuropsychiatry,
and in neurobehavioral disorders. These EEG aberrations may be reflective of underlying morpho-functional brain abnormalities that underpin various neurobehavioral disturbances.

Real the full article here – Electroencephalographic Cerebral Dysrhythmic Abnormalities in the Trinity of Nonepileptic General Population, Neuropsychiatric, and Neurobehavioral Disorders

(The Journal of Neuropsychiatry and Clinical Neurosciences 2008; 20:7?22)

What Happened to the Reporter at the Grammys?

Recently during a post-Grammy interview, the on-air report had some serious difficulties in getting her words out. You can read about it and see the video here .

The reporter in this article likely had a TIA… a Transient Ischemic Attack… the temporary insufficiency of vascular flow dynamics to a cortical area providing insufficient local glucose and oxygen for function. This can happen from just flow dynamics due to vasoconstriction, such as seen in hyperventilation or gross over-arousal. This can also happen when blood consistency is not appropriate to allow flow, such as seen with hyperglycemia in diabetics when their blood sugar rises too high.

You may think “what does this have to do with EEG?”… well it is an important EEG area, and not without controversy.

The mid-temporal sharp-slow transients that are seen in EEG are considered neurologically non-specific, and many neurologists do not even comment on them. This is a mistake, as these nonspecific changes are a harbinger of vascular issues, including ischemia (as seen in migraine ischemia and the current discussion of TIAs), or vascular insufficiency, commonly in the vertebro-basillar artery and posterior vascular distributions supplying the hippo-campus (which has a huge metabolic demand load).

No less than Ernst Neidermayer chastises the neurologists doing EEG interpretations for under-reading of these findings. He clearly shows in his paper that these non-specific findings are important.

Recently I had a client who sent in the EEG of his wife, who had experience some word-finding and fluency issues, and it had these “nonspecific” temporal findings on the left… we suggested an MRA (magnetic resonance angiography), and though they had already done the MRI (which was normal), the MRA was done. The MRA showed a 9 millimeter AV malformation, and surgery was done to patch this area so it didn’t burst, saving her life.

These are the sort of waveform distortions that require an experienced EEG interpretation, and preferably an expert with Board qualification in EEG, not just someone licensed to read EEGs. These controversial findings make all the difference, and it is exactly these areas that provide the large difference between interpretation in studies looking at inter-reader visual EEG reliability.

Jay

Epilepsy and EEG

Epilepsy and EEG have been inextricably linked since the 1930s, when Frederick and Erna Gibbs discovered that epileptic events were visible in the EEG. The evolution of other medical imaging in the 1970s and 1980s provided a better way to localize tumors, and the clinical use tapered off in areas other than epilepsy and encephalopathies. Even with the multiplicity of other methods, the EEG remains the gold standard for identification of epilepsy.

In modern neuroscience centers, the EEG is still the tool of choice in evaluation of convulsive epilepsy, as well as some other non-convulsive forms, such as staring episodes seen in “absence epilepsy” typically as a 3/second spike and wave dominant anteriorly, or temporal lobe epilepsy, which is seen as a “notched” slow wave discharge fronto-temporally.