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During atonic seizures there is a temporary lapse in muscle tone. These episodes last for usually less than few seconds. Sudden head drop while standing, sitting is common. The characteristic of absence seizures is abrupt and sudden onset impairment of consciousness, a blank stare or possibly a brief upward rotation of the eyes. The only diagnostic test for absence seizures and atonic seizures is EEG. MRI brain may be needed to rule out diseases like stroke or a brain tumor. It is advisable to see a neurologist. After a thorough systemic and neurological examination he will advise you investigations. Do keep us posted.
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