Electroencephalogram (EEG) in a Neuropsychiatry clinic, questions you are too embarrassed to ask!

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1 Electroencephalogram (EEG) in a Neuropsychiatry clinic, questions you are too embarrassed to ask! Marco Mula MD PhD Consultant in Neurology and Epileptology, Honorary Consultant in Neuropsychiatry, Honorary Senior Lecturer Excellence in specialist and community healthcare Disclosures No conflicts of interest 1

2 Outline History and basic elements of EEG signal EEG in epilepsy EEG in neurology EEG in psychiatry History of EEG 1791 Galvani nerve tissue has intrinsic electrical activity 1875 Caton records brain potentials from cortex 1883 Marxow discovers evoked potentials Hans Berger ( ) 1929 Berger records electrical activity from the skull 2

3 Strength and Advantages of EEG Is a measure of brain electrical function; supplement neuroimaging studies Provides direct rather than indirect evidence of epileptic abnormality May be the only test that shows abnormalities in epileptic patients Provides some spatial or localization information Low cost Low morbidity Readily repeatable Portable / ambulatory The International 10/20 System Nasion: point between the forehead and the skull Inion: bump at the back of the skull Location: Frontal, Temporal, Parietal, Occipital, Central z for the central line Numbers: Even numbers (2,4,6) right hemisphere, odd (1,3,5) left 3

4 EEG in the States of Vigilance Frequency Ranges Beta: Hz Alpha: 8 13 Hz Theta: 5 7 Hz Delta: 1 4 Hz Interictal EEG is NOT a diagnostic test for epilepsy! Prevalence of interictal epileptiform discharges in nonepileptic subjects: 0.5% healthy adults 2% - 4% healthy children 10% - 30% cerebral pathologies (i.e. tumor, congenital brain injury, cranial surgery) 4

5 Temporal lobe status (Gastaut 1956) Generalized vs. Focal non-convulsive status Continuous form vs. Cyclic form (partial responsiveness) Temporal type vs. Extra-temporal type (impairment of consciousness, speech disturbances) Temporal lobe or psychomotor status epilepticus. A case report Wieser HG Electroencephalogr Clin Neurophysiol 1980;48: Fp1-F7 Fp2-F8 F7-FT9 FT9-T7 F8-FT10 FT10-T8 P7--01 P8-02 5

6 Psychiatric manifestations of nonconvulsive status epilepticus Riggio S Mt Sinai J Med 2006;73:960-6 Steroid-responsive encephalopathy associated with autoimmune thyroiditis (SREAT/Hashimoto) Autoimmune (NMDAR Ab) Paraneoplastic (Caspr2 Ab) The Landolt s phenomenon Forced Normalization is the phenomenon characterised by the fact that, with the occurrence of the psychotic states, the EEG becomes more normal or entirely normal as compared with previous and subsequent EEG findings Hans Landolt ( ) ILAE Vice - President

7 J Epileptology 2010;18:39-44 The Nature of Aggression during Epileptic Seizures Antonio V. DelgadoEscueta, M.D.Richard H. Mattson, M.D.Lambert King, M.D.Eli S. Goldensohn, M.D., and Herbert Spiegel, M.D.Jack Madsen, M.D.Paul Crandall, M.D.Fritz Dreifuss, M.D.Roger J. Porter, M.D. 1:1000 seizures N Engl J Med 1981; 305: Aggressive conduct towards nearby objects/persons Violent motor automatisms misinterpreted as threatening or assaultive Full amnesia and profound remorse 7

8 Epilepsy and violence: medical and legal issues David M Treiman Epilepsia 1986;27(Suppl 2)S77-S104 a) An established diagnosis of epilepsy b) The video-eeg documentation of epileptic automatisms c) The video-eeg documentation of the aggressive behaviour d) The aggressive act should be characteristic of the patient's habitual seizures EEG is NOT helpful for: Specifying aetiology Distinction between acute and chronic processes Early detection of dementia Periodic patterns: FIRDA (Frontal Intermittent Rhythmic Delta Activity) PLEDs (Periodic Lateralised Epileptiform Discharges) TW (Triphasic Waves) 8

9 Electroencephalographic Cerebral Dysrhythmic Abnormalities in the Trinity of Nonepileptic General Population, Neurobehavioral Disorders Disorder EEG abnormalities N papers Schizophrenia 20% - 60% 10 Mood disorders 20% - 40% 18 Panic attack 25% - 30% 8 Borderline personality disorder Antisocial personality disorder / Violent behaviour 6.3% - 46% 11 24% - 78% 20 PNES without epilepsy 12.3% % 11 Confounders: Psychotropic drug treatment; Hx alcohol and substance abuse; Hx brain insults; Multiple head injuries Usefulness of screening EEGs in a psychiatric inpatient population Warner MD, Boutros NN, Peabody CA J Clin Psychiatry 1990;51: psychiatric inpatients: EEG abnormal 31% Change in diagnosis because of EEG 1.7% 9

10 QEEG Low Resolution Electromagnetic Tomography (LORETA) Event related potentials (ERP) Distinguish between dementia and depression Distinguish between schizophrenia and mood disorders Distinguish between environmentally induced and endogenously mediated behavioural disorders POOR EVIDENCE! Psychotropic drugs and seizures The Chronology 1952 Chlorpromazine Anton-Stephens D. Preliminary observations on the psychiatric use of chlorpromazine. J Ment Sci 1953; 100: Imipramine Leyberg JT, Denmark JC. The treatment of depressive states with imipramine hydrochloride (Tofranil). J Ment Sci 1959;105: Blair D. Treatment of severe depression by imipramine: an investigation of 100 cases. J Ment Sci 1960; 106: Sharp WL. Convulsions associated with anti-depressant drugs. Am J Psychiatry 1960; 117:

11 EEG changes with TCAs Kiloh LG, Davison K, Ossleton JW. An electroencephalographic study on the analeptic effects of imipramine. Electroencephalogr Clin Neurophysiol 1961; 12: Davison K. EEG activation after intravenous amitriptyline. Electroencephalogr Clin Neurophysiol 1965; 19: Redding FK. EEG activation with amitriptyline. Electroencephalogr Clin Neurophysiol 1969; 26: Legg NJ, Swash M. Clinical note: seizures and EEG activation after trimipramine. Epilepsia 1974; 15: Drugs modifying dopaminergic activity and behaviour, the EEG and epilepsy in papio papio. Meldrum B, Anlezark G, Trimble M. Eur J Pharmacol 1975; 32:

12 EEG alterations and seizures during treatment with clozapine. A retrospective study of 283 patients. Gunther W, Baghai T, Naber D, Spatz R, Hippius H Pharmacopsychiatry 1993;26:69-74 Before Six hours after Clozapine 0.36 mg/kg Abnormal EEG activities induced by psychotropic drugs Spatz R, Kugler J Electroencephalogr Clin Neurophysiol Suppl 1982;36: EEGs 593 pts EEG abnormalities: Clozapine 59% Lithium 50% Haloperidol 44% Maprotiline 37% GTCS over 3.5 year FUP period: 1% clozapine <0.5% other medications 12

13 Psychotropic drug-related seizures Risk factors Patient-related Hx of epilepsy Family Hx of epilepsy Brain disorder (post-natal brain damage, head injury, dementia) Treatment-related High-dose or overdose Rapid titration Abrupt withdrawal of other drugs (i.e. benzodiazepines or antiepileptic drugs) Pharmacodynamic interactions (i.e. effect on seizure threshold) Pharmacokinetic interactions (i.e. inhibition -> overdose/highdose) Stimmel & Dopheide CNS Drugs 1996; Mula et al. Expert Opin Pharmacother

14 Pharmacovigilance Definitions Adverse event (temporally related but not necessarily casually related) Adverse reaction (noxious and unintended; occurring at normal doses) Unexpected adverse reaction (not consistent with drug information) Serious adverse reaction (any untoward medical occurrence that at any dose results in death, hospitalization or prolongation of existing hospitalization or persistent of significant disability or incapacity) Side effect (unintended; occurring at normal doses; biologically plausible) WHO 2002 Evidence for seizures as side effects of antidepressants? Accurate time frame Evidence for biological gradient (dose-dependency) Evidence for a biological mechanism Increased prevalence of seizures in the exposed population Mostly Established for: Clomipramine/amitriptyline Maprotiline Bupropion (IR vs XR) Clozapine Established for maprotiline Established for: Clomipramine/amitriptyline Maprotiline Bupropion (IR vs XR) Clozapine 14

15 Conclusions Low cost, low morbidity, non-invasive, easily repeatable NOT for diagnosis, aetiology, distinguish between acute and chronic, screening purposes Specific question/indication Should be always part of routine investigations for: Acute confusional state Cognitive, attentional and developmental disorders in children 15