This lecture is all about the recognition of an abnormal EEG, its characteristics, its appearance and all about how to differentiate the abnormal activity with normal EEG background.
This presentation looks at abnormal EEG patterns with examples for each. Benign variants, artifacts and focal ictal patterns are not part of this presentation.
This lecture is all about the recognition of an abnormal EEG, its characteristics, its appearance and all about how to differentiate the abnormal activity with normal EEG background.
This presentation looks at abnormal EEG patterns with examples for each. Benign variants, artifacts and focal ictal patterns are not part of this presentation.
This presentation looks at generalised periodic epileptiform discharges and the various disorders like Creutzfeldt Jacob disease (CJD), SSPE and metabolic encephalopathies in which it is seen. SIRPID is also discussed. Triphasic waves are described. Radermacker complexes in SSPE are described.
Event Related Potentials, Cognitive Evoked Potentials. These are stimulus unrelated potentials, which depend on the patient's ability to differentiate between a rare stimulus and a common stimulus.
This presentation discusses the basic principles governing EEG Rhythm Generation, and discusses the various circuits that generate and maintain cerebral oscillations.
Transcranial magnetic stimulation (TMS) is a noninvasive method to cause depolarization or hyperpolarization in the neurons of the brain.
This video explains the physics of this method and how it can be used in daily practice.
More about magnetic simulators: http://www.neurosoft.ru/eng/product/neuro-msd/index.aspx
This presentation looks at EEG signal generation, pyramidal cells, recording of EEG, source localisation, polarity, analysis of dipole, derivations, montages,
This presentation looks at generalised periodic epileptiform discharges and the various disorders like Creutzfeldt Jacob disease (CJD), SSPE and metabolic encephalopathies in which it is seen. SIRPID is also discussed. Triphasic waves are described. Radermacker complexes in SSPE are described.
Event Related Potentials, Cognitive Evoked Potentials. These are stimulus unrelated potentials, which depend on the patient's ability to differentiate between a rare stimulus and a common stimulus.
This presentation discusses the basic principles governing EEG Rhythm Generation, and discusses the various circuits that generate and maintain cerebral oscillations.
Transcranial magnetic stimulation (TMS) is a noninvasive method to cause depolarization or hyperpolarization in the neurons of the brain.
This video explains the physics of this method and how it can be used in daily practice.
More about magnetic simulators: http://www.neurosoft.ru/eng/product/neuro-msd/index.aspx
This presentation looks at EEG signal generation, pyramidal cells, recording of EEG, source localisation, polarity, analysis of dipole, derivations, montages,
These are the slides that I presented at the first Brain Control Club hackathon in Paris, see http://cri-paris.org/scientific-clubs/brain-control-club/
SSPE, dr. amit vatkar, pediatric neurologistDr Amit Vatkar
Subacute sclerosing pan encephalitis (SSPE) also known as Dawson Disease, Dawson encephalitis, and measles encephalitis is a rare and chronic form of progressive brain inflammation caused by a persistent infection with measles virus.
In this presentaion i will a case a sspe and give u some information regarding daignosis and treatment
Normal EEG patterns, frequencies, as well as patterns that may simulate diseaseRahul Kumar
This presentation discusses the vast range of traces that show the variations in normal EEG patterns, as well as discussing the frequency and amplitudes of various normal waveforms.
This presentation is an introduction to the principles of Nerve Conduction Study and is entirely sourced from the book by David C Preston and Barbara E Shapiro: Electromyography and Neuromuscular disorders, 3rd Edition
'Non-pharmacological management in dementia' is really nice article published in British Journal of Psychiatry Advances. It gives basic idea about non pharmacological management in all forms of dementia for Behavioral and psychological symptoms of dementia.
This presentation gives detailed description of symptoms of catatonia with its etiologies and differential diagnoses. It should help to differentiate catatonia in neurological and psychiatric disorders.
Ethanol (CH3CH2OH), or beverage alcohol, is a two-carbon alcohol
that is rapidly distributed in the body and brain. Ethanol alters many
neurochemical systems and has rewarding and addictive properties. It
is the oldest recreational drug and likely contributes to more morbidity,
mortality, and public health costs than all illicit drugs combined. The
5th edition of the Diagnostic and Statistical Manual of Mental Disorders
(DSM-5) integrates alcohol abuse and alcohol dependence into a single
disorder called alcohol use disorder (AUD), with mild, moderate,
and severe subclassifications (American Psychiatric Association, 2013).
In the DSM-5, all types of substance abuse and dependence have been
combined into a single substance use disorder (SUD) on a continuum
from mild to severe. A diagnosis of AUD requires that at least two of
the 11 DSM-5 behaviors be present within a 12-month period (mild
AUD: 2–3 criteria; moderate AUD: 4–5 criteria; severe AUD: 6–11 criteria).
The four main behavioral effects of AUD are impaired control over
drinking, negative social consequences, risky use, and altered physiological
effects (tolerance, withdrawal). This chapter presents an overview
of the prevalence and harmful consequences of AUD in the U.S.,
the systemic nature of the disease, neurocircuitry and stages of AUD,
comorbidities, fetal alcohol spectrum disorders, genetic risk factors, and
pharmacotherapies for AUD.
ARTIFICIAL INTELLIGENCE IN HEALTHCARE.pdfAnujkumaranit
Artificial intelligence (AI) refers to the simulation of human intelligence processes by machines, especially computer systems. It encompasses tasks such as learning, reasoning, problem-solving, perception, and language understanding. AI technologies are revolutionizing various fields, from healthcare to finance, by enabling machines to perform tasks that typically require human intelligence.
Flu Vaccine Alert in Bangalore Karnatakaaddon Scans
As flu season approaches, health officials in Bangalore, Karnataka, are urging residents to get their flu vaccinations. The seasonal flu, while common, can lead to severe health complications, particularly for vulnerable populations such as young children, the elderly, and those with underlying health conditions.
Dr. Vidisha Kumari, a leading epidemiologist in Bangalore, emphasizes the importance of getting vaccinated. "The flu vaccine is our best defense against the influenza virus. It not only protects individuals but also helps prevent the spread of the virus in our communities," he says.
This year, the flu season is expected to coincide with a potential increase in other respiratory illnesses. The Karnataka Health Department has launched an awareness campaign highlighting the significance of flu vaccinations. They have set up multiple vaccination centers across Bangalore, making it convenient for residents to receive their shots.
To encourage widespread vaccination, the government is also collaborating with local schools, workplaces, and community centers to facilitate vaccination drives. Special attention is being given to ensuring that the vaccine is accessible to all, including marginalized communities who may have limited access to healthcare.
Residents are reminded that the flu vaccine is safe and effective. Common side effects are mild and may include soreness at the injection site, mild fever, or muscle aches. These side effects are generally short-lived and far less severe than the flu itself.
Healthcare providers are also stressing the importance of continuing COVID-19 precautions. Wearing masks, practicing good hand hygiene, and maintaining social distancing are still crucial, especially in crowded places.
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Title: Sense of Smell
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the primary categories of smells and the concept of odor blindness.
Explain the structure and location of the olfactory membrane and mucosa, including the types and roles of cells involved in olfaction.
Describe the pathway and mechanisms of olfactory signal transmission from the olfactory receptors to the brain.
Illustrate the biochemical cascade triggered by odorant binding to olfactory receptors, including the role of G-proteins and second messengers in generating an action potential.
Identify different types of olfactory disorders such as anosmia, hyposmia, hyperosmia, and dysosmia, including their potential causes.
Key Topics:
Olfactory Genes:
3% of the human genome accounts for olfactory genes.
400 genes for odorant receptors.
Olfactory Membrane:
Located in the superior part of the nasal cavity.
Medially: Folds downward along the superior septum.
Laterally: Folds over the superior turbinate and upper surface of the middle turbinate.
Total surface area: 5-10 square centimeters.
Olfactory Mucosa:
Olfactory Cells: Bipolar nerve cells derived from the CNS (100 million), with 4-25 olfactory cilia per cell.
Sustentacular Cells: Produce mucus and maintain ionic and molecular environment.
Basal Cells: Replace worn-out olfactory cells with an average lifespan of 1-2 months.
Bowman’s Gland: Secretes mucus.
Stimulation of Olfactory Cells:
Odorant dissolves in mucus and attaches to receptors on olfactory cilia.
Involves a cascade effect through G-proteins and second messengers, leading to depolarization and action potential generation in the olfactory nerve.
Quality of a Good Odorant:
Small (3-20 Carbon atoms), volatile, water-soluble, and lipid-soluble.
Facilitated by odorant-binding proteins in mucus.
Membrane Potential and Action Potential:
Resting membrane potential: -55mV.
Action potential frequency in the olfactory nerve increases with odorant strength.
Adaptation Towards the Sense of Smell:
Rapid adaptation within the first second, with further slow adaptation.
Psychological adaptation greater than receptor adaptation, involving feedback inhibition from the central nervous system.
Primary Sensations of Smell:
Camphoraceous, Musky, Floral, Pepperminty, Ethereal, Pungent, Putrid.
Odor Detection Threshold:
Examples: Hydrogen sulfide (0.0005 ppm), Methyl-mercaptan (0.002 ppm).
Some toxic substances are odorless at lethal concentrations.
Characteristics of Smell:
Odor blindness for single substances due to lack of appropriate receptor protein.
Behavioral and emotional influences of smell.
Transmission of Olfactory Signals:
From olfactory cells to glomeruli in the olfactory bulb, involving lateral inhibition.
Primitive, less old, and new olfactory systems with different path
NVBDCP.pptx Nation vector borne disease control programSapna Thakur
NVBDCP was launched in 2003-2004 . Vector-Borne Disease: Disease that results from an infection transmitted to humans and other animals by blood-feeding arthropods, such as mosquitoes, ticks, and fleas. Examples of vector-borne diseases include Dengue fever, West Nile Virus, Lyme disease, and malaria.
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The "New Drug Discovery and Development" process involves the identification, design, testing, and manufacturing of novel pharmaceutical compounds with the aim of introducing new and improved treatments for various medical conditions. This comprehensive endeavor encompasses various stages, including target identification, preclinical studies, clinical trials, regulatory approval, and post-market surveillance. It involves multidisciplinary collaboration among scientists, researchers, clinicians, regulatory experts, and pharmaceutical companies to bring innovative therapies to market and address unmet medical needs.
Ozempic: Preoperative Management of Patients on GLP-1 Receptor Agonists Saeid Safari
Preoperative Management of Patients on GLP-1 Receptor Agonists like Ozempic and Semiglutide
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New Directions in Targeted Therapeutic Approaches for Older Adults With Mantl...i3 Health
i3 Health is pleased to make the speaker slides from this activity available for use as a non-accredited self-study or teaching resource.
This slide deck presented by Dr. Kami Maddocks, Professor-Clinical in the Division of Hematology and
Associate Division Director for Ambulatory Operations
The Ohio State University Comprehensive Cancer Center, will provide insight into new directions in targeted therapeutic approaches for older adults with mantle cell lymphoma.
STATEMENT OF NEED
Mantle cell lymphoma (MCL) is a rare, aggressive B-cell non-Hodgkin lymphoma (NHL) accounting for 5% to 7% of all lymphomas. Its prognosis ranges from indolent disease that does not require treatment for years to very aggressive disease, which is associated with poor survival (Silkenstedt et al, 2021). Typically, MCL is diagnosed at advanced stage and in older patients who cannot tolerate intensive therapy (NCCN, 2022). Although recent advances have slightly increased remission rates, recurrence and relapse remain very common, leading to a median overall survival between 3 and 6 years (LLS, 2021). Though there are several effective options, progress is still needed towards establishing an accepted frontline approach for MCL (Castellino et al, 2022). Treatment selection and management of MCL are complicated by the heterogeneity of prognosis, advanced age and comorbidities of patients, and lack of an established standard approach for treatment, making it vital that clinicians be familiar with the latest research and advances in this area. In this activity chaired by Michael Wang, MD, Professor in the Department of Lymphoma & Myeloma at MD Anderson Cancer Center, expert faculty will discuss prognostic factors informing treatment, the promising results of recent trials in new therapeutic approaches, and the implications of treatment resistance in therapeutic selection for MCL.
Target Audience
Hematology/oncology fellows, attending faculty, and other health care professionals involved in the treatment of patients with mantle cell lymphoma (MCL).
Learning Objectives
1.) Identify clinical and biological prognostic factors that can guide treatment decision making for older adults with MCL
2.) Evaluate emerging data on targeted therapeutic approaches for treatment-naive and relapsed/refractory MCL and their applicability to older adults
3.) Assess mechanisms of resistance to targeted therapies for MCL and their implications for treatment selection
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Ve...kevinkariuki227
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Verified Chapters 1 - 19, Complete Newest Version.pdf
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Verified Chapters 1 - 19, Complete Newest Version.pdf
These simplified slides by Dr. Sidra Arshad present an overview of the non-respiratory functions of the respiratory tract.
Learning objectives:
1. Enlist the non-respiratory functions of the respiratory tract
2. Briefly explain how these functions are carried out
3. Discuss the significance of dead space
4. Differentiate between minute ventilation and alveolar ventilation
5. Describe the cough and sneeze reflexes
Study Resources:
1. Chapter 39, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 34, Ganong’s Review of Medical Physiology, 26th edition
3. Chapter 17, Human Physiology by Lauralee Sherwood, 9th edition
4. Non-respiratory functions of the lungs https://academic.oup.com/bjaed/article/13/3/98/278874
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3. What is EEG ?
• EEG (Electroencephalogram) refers to recording and analysis
of electrical activity of brain recorded by amplifying voltage
differences between electrodes placed on scalp or cerebral
cortex .
• This electrical potential is produced by excitatory or inhibitory
post synaptic electrical discharges from neuronal dendrites at
cortical surfaces.
• Such neurons constitute only 5% of total neurons of the brain.
• Voltage recorded on EEG is only 10% of the voltage recorded
on ECG due to high resistance of skull.
3
5. RECORDINGS FROM ANIMAL BRAIN
• First person to record electrical
activity from animal brain in
1874.
RICHARD CATON , 1874 5
6. RECORDING FROM HUMAN BRAIN
• First recording from human
scalp in 1924.
• Report published in 1929
• Danis William started clinical
use to localize brain trauma
during ww II in oxford.
HANS BERGER 1924 6
7. Hans Berger 1835-1911: Human EEG
Prof of Psychiatry, University of Jena
Germany, Removed from job in one
day notice by the Nazis, committed
suicide
Berger wave
7
13. • Montage refers to the particular combination of electrodes
examining at a particular point of time.
• When a single reference point is used for all electrodes
Referential montage.
• When several referential points are used for recording Bipolar
montage.
• In bipolar montage the electrodes form a chain passed side by side
or front to back.
MONTAGE
13
14. REFERENCE MONTAGE • Connects active
scalp electrodes
and an inactive
electrode placed
away from the
scalp e.g. on ear,
nose or chin
[Reference
electrode]
– Disadvantage
with ear-
some brain
activity
– Chin & nose-
heart activity
• Useful for seeing
amplitude of
waves
14
15. BIPOLAR MONTAGE
• Connects two active
scalp electrodes
• Each channel is
attached to two
different electrodes
• Arrangement of
channels in
montages-
– Anteriorly placed
electrodes on
initial channels-
helps see
progression of
waves
– Alternate left and
right electrodes-
helps compare the
two sides
15
16. • Electrodes- 21
• Sensitivity- 5-10 micro volts/mm ( avg 7)
• Paper speed – 3 cm/ sec ( adjustable)
• Length of recording – 2 min each montage
- 30 min awake record (10 min
sleep)
• Activation – Hyperventilation – 3min + 1min
- Photic st -30 cm 10,15,20,30,40 Hz
,each in trains of 10 sec.
STANDARDS
16
19. Found in normal eye
closed EEG
Highly rhythmic
Frequency 8 to 13 HZ
Prominent in the posterior
cortex
Mainly occipital , temporal
and parietal cortex
NORMAL ALPHA WAVES
19
20. NORMAL BETA WAVE
Frequent in normal
eye open EEG
EEG waves of >13 HZ
Usually of low voltage
Found in frontal and
central region
20
22. NORMAL THETA WAVES
Small amount of
sporadic and isolated
activity found in normal
awake state
Prominent in drowsy
and sleep EEG tracing
EEG activity of 4 to 7
HZ
found in frontal and
temporal region
22
23. NORMAL DELTA ACTIVITY
Not present in normal
awake EEG
Prominent in normal
deeper stage of sleep.
A frequency of < 4 Hz.
23
25. Amplitude
• Measured: peak to peak
• Expressed as range i.e 40-50μv
• Depends on
– Inter electrode distance
– Type of montage
– Type of recording
• surface (10-100 μv)
• Depth 500-1500 μv
25
27. • Hyperventilation - causes cortical hypocapnia-> cerebral
vasoconstriction and hypoxia -> may allow epileptic foci to
become evident
• Photic stimulation - a strobe light flashing at 8-15 Hz is used to
capture the occipital α frequency - α frequency adjusts to
match that of the strobe - may allow epileptic foci to be seen
and may even induce epileptic seizures, as may a flickering
television screen
• Sleep deprivation.
• Sleep EEG
ACTIVATION
27
28. • Depth electrodes
• Ambulatory (24-hour) EEG
• Q-EEG/BEAM/Brain Mapping/rEEG
Multichannel recording of eyes-closed, resting EEG - visually
edited & a sample of artifact-free data, analyzed, using the
Fast Fourier Transform (FFT) to quantify the power at each
frequency of the EEG averaged across the entire sample,
known as the power spectrum.
QEEG findings are then compared to a normative database
This database consists of brain map recordings of several
hundred healthy individuals
Comparisons are displayed as Z scores, which represent
standard deviations from the norm.
EEG TECHNIQUES
28
29. • Absolute power
This refers to the amount of activity within a specific frequency
band of brain waves
• Relative power
This refers to the relative amount of activity within a specific
frequency band compared to all the other frequency bands
• Coherence
Measure of synchronization between activity in two channels
• Symmetry
Ratio of power in each band between a symmetrical pair of
electrodes 29
30. LORETA (Low Resolution Electromagnetic Tomography) -
Complex mathematical calculations to construct a visual image
of the 3D electrical activity of deep parts of the brain from
surface electrical measures
30
31. EEG techniques (continued..)
• Video EEG/Video telemetry- Simultaneous recording of brain
activity on an EEG and behavior on tape or digital video
• ERP - An event-related potential (ERP) is any stereotyped
electrophysiological response to an internal or external
stimulus.
• Polysomnography – Simultaneous recording of EEG, muscle
tone, oculogram, respiration.
31
41. • In deep drowsiness, stage I (may persist during
stage II & III)
• 50-80% in normal adults
• Location – occipital
• Monophasic, triangular
• 1Hz (4-6 Hz rare)
POSITIVE OCCIPITAL SHARP TRANSIENT OF SLEEP
(POSTS)
41
44. • 12-14Hz, slowed with ↑sleep
• Waxing & waning
• Location: fronto cental
• Origin: Deep frontal & thalamus
SLEEP SPINDLES
44
45. • Positive followed by large negative
wave
• May precede or follow smaller waves
of opposite polarity
• Maximum at vertex may extend to
frontal & parietal region
• Bilaterally synchronous
• Appear by 5month, prominent in
youth
• Not suppressed by focal lesion
VERTEX SHARP WAVES
45
53. AWAY FROM NORMALITY
WAVE EEG
AMPLITUDE SPIKES / SHARP WAVES
RHYTHM SLOW / FAST / PERIODIC DISCHARGES
COMMON IS THE PERMUTATION AND COMBINATION OF THE TWO
53
55. SPIKES
It is a transient discharge , clearly distinguished from the
background activity , having pointed peak and duration of 20
to 70 m sec. in conventional paper speed.
The main component is generally negative and amplitude is
variable.
The after coming slow wave is surface negative and depict
long hyper polarization.
Positive waves are common in in depth recording.
Spikes increased after seizure , but not increased prior to
seizure (Gotman 1984)
55
57. ROLANDIC SPIKES
Misnomer as the total
duration is more than 70 m
sec
Appears as isolated spikes
in centrotemoral region.
In BCECTS
The entire complex
consists of 80 to 120 ms
57
58. SHARP WAVES
• Sharp waves are defined as transient discharges clearly
distinguished from background activity having pointed peak
and at conventional paper speed it has a duration of 70 – 200
m sec.
• The main component is usually negative with ascending
component is sharp but descending component is slow.
58
67. ABRUPT LOSS OF VOLTAGE DUE TO DESYNCHRONYSATION
THERE IS 20 – 40 HZ FAST ACTIVITY
1 - 3 SEC
APPROXIMATELY 10 HZ SPIKE WAVE WITH HIGH AMPLITUDE
APROXIMALTELY 10 SEC
FREQUENCY SLOWS DOWN AND COME TO DELTA RANGE
ONCE 4 HZ REACHED THEN SLOW WAVES INTERUPT THE RECURRING
RHYTHM
IT FOLLOWS THE POST ICTAL FLATNESS
GRADUALLY DETA , ALPHA THE BETA RANGE WAVES RETURNS
GENERALIZED TONIC CLONIC SEIZURE
67
69. ABSENCE SEIZURE
Characteristics are 3 HZ spike
wave complex
Appears and goes of abruptly on
normal background activity
Maximum at frontal and midline
region
Starts at 4 HZ then slows down to
3.5 HZ then up to 2.5 Z
Hyperventilation precipitate such
attacks
Paroxysm of more than 5 sec
leads to clinical seizure69
70. SIMPLE PARTIAL SEIZURE
• Consciousness is fully preserved.
• EEG shows
» Spikes over the involved cortex
» Wide spread desynchronisaton , more or less
theta and delta activity.
» Uninvolved regions shows normal EEG pattern
70
72. COMPLEX PARTIAL SEIZURE
•EEG is variable
•Nasopharyngeal and
sphenoiddal electrode is
helpful in recording
•Temporal spikes are
common.
•The EEG may show 4Hz flat
topped waves and 6 Hz flat-
topped waves
72
73. JAPANESE ENCEPHALITIS
It include the diminution of
electrical activity
Slow waves are important
the changes are not
characteristic
It depicts the severity of
the illness
Improvement occurs with
the corresponding
improvement of the EEG
73
74. HEPATIC ENCEPHALOPATHY
Stage consciousness EEG
I Alert Normal
II Drowsy Slow alpha , poorly developed K-
complex and sleep spindle
III Stupor Theta activity , absence of sleep
pattern
IV Coma Tri-phasic wave
V Deep coma Delta wave
VI Deep coma Flat EEG
74
75. EEG of a case of hepatic encephalopathy after vaproate toxicity , fig1 shows diffuse
slowing of activity , fig 2 shows improvement after treatment ( curtsy – international
journal of neurology Feb’ 09)
EEG OF HEPATIC ENCEPHALOPATHY
Fig 1 Fig 2
75
76. DELIRIUM TREMENS
Beta predominance with
spares normal alpha during
acute florid stage
Persistent delta with little
beta and alpha
During recovery the first to
predominant beta with
spares alpha
Those who exhibits
persistent theta suggests
residual brain damage.Beta prominence in the EEG
76
77. PERIODIC DISCHARGE
• Periodic discharges are of high amplitude and it may me spike
or sharp waves and the duration may exceeds 150 m sec and
recurring at periodic interval.
• It may be the most important EEG finding for ongoing CNS
disease or some CNS infections.
• Morphology me be specific for the disease-
• Burst suppression
• Repetitive sharp waves
• Periodic triphasic
• Focal periodic
• Generalized periodic slow waves
77
78. SSPE
Occurs in a minor percentage of cases of measles
virus infection.
1. Periodic discharge dominates the picture.
2. Duration of 0.5 – 3 sec
3. Average of 500 mic volt
4. Every 4 – 16 sec interval
5. Giant slow waves
6. Discharges are mixed
7. Prominent in the vertex
8. There may be accompanying myoclonus
78
80. CREUZFELDT – JAKOB DISEASE
• It is a prion disease.
• The EEG characteristics are as follows:
– In the first stage there is non specific change in the EEG
– In the 2nd stage patient developed
1. Periodic tri-phasic / bi-phasic complexes
2. Duration of 100-300 m.sec
3. Reparation every 0.5 to 2 sec
4. It is most prominent in anterior region
5. Later stages slow waves become prominent
80
82. HERPES SIMPLEX ENCEPHALITIS
• The EEG finding of HSE is highly suggestive (but not
pathogomonic).
• EEG shows-
• Early stage there is focal or lateralized polymorphic
delta activity on same side.
• Slow wave later involve frontotemporal region.
• Sharp slow wave recurring at every 1-5 sec interval.
• The complex comprises of upto1000ms.
• Usually appears with in 2 to 15 days but may appear
after 30 days.
82
84. CEREBRAL ANOXIA
On flat back ground
generalized synchronous
repetitive simple or
compound sharp waves.
Associated with
myoclonus.
Occurs with a burst and
suppression burst pattern.
84
85. FOCAL BRAIN LESIONS
• The types of EEG abnormality in focal brain lesions are:
– Abnormal background rhythm
– Focal absence of neuronal activity tumor area
– Burst suppression pattern abutting area
– Continuous slow wave most distal zone
– Arrhythmic focal hemispheric or generalized delta
activity
– Less than 4 HZ delta activity
– Continuous or sporadic
– Destructive lesions abscess, hematoma are
associated
85
86. FOCAL BRAIN LESION
– Intermittent rhythmic slow activity:
– It may be of theta or delta range
– Independently or mixed
– Infra-tentorial, supra-tentorial or peri-ventricular
tumor.
– Epileptiform activity
– Focal in onset
– Localized hemispheric lesion
– Often accompanied by slowing of activity
86
88. DEGENERATIVE DISEASE
• The EEG change in the degenerative disease is non
specific.
• There was no consistent difference between cortical
or sub-cortical dementia.
• But sub-cortical dementia shows more normal EEG
• Multi-infract condition may show some lateralizing
sign.
88
89. DEGENERATIVE DISEASE
• Alzheimer's disease:
• Initially there was irregular theta activity
• Later become prominent back ground activity
• Lastly delta activity become prominent
• Fronto-temporal dementia :
• EEG remains persistently normal
• Quantitative analysis showed some abnormality
• Huntingtons disease:
• > 10 µv beta activity is characteristic
89
90. EEG OF A CASE OF ALZHEIMERS DISEASE
EEG of Alzheimer's disease showing irregular theta activity. 90
92. SCHIZOPHRENIA
• S-EEG findings in schizophrenia is non specific
Widespread slow activity
Diffuse Dysrhythmia
Spikes or spike-wave complex
• Q- EEG abnormality -extensively examined:
Extensive slow wave rhythm preponderance
Delta activity anterior brain region
Theta activity posterior brain region
Beta activity with small increase in amplitude
92
93. MOOD DISORDER
• Most of the studies suggests-
• Increased beta / alpha power
• Asymmetric increase in alpha / beta activity in left
frontal region
• Less alpha power and higher EEG findings are seen in
subclinical and depressed patients relatives.
• Recently Q-EEG used as the predictor for
antidepressant response.
93
94. ANTISOCIAL AND BORDERLINE PERSOANLITY DISORDER
• Antisocial personality disorder:
• Frequently associated with organic brain pathology.
• Abnormal behavior is frequently but non specific EEG
changes.
• Borderline personality disorder:
• A number of patients subsequently diagnosed as
complex partial seizure.
• 40 – 80 % have back ground slowing of activity.
• ¼ th of cases have 6 to 14 / sec spike activity might be
the correlate of episodic impulsive activity.
94
95. ATTENTION DEFICIT HYPERACTIVITY DISORDER
• 1/3rd had EEG abnormality.
• Pediatric Neurology reports Epiletiform discharges in ADHD
patients.
• Q-EEG showed increased activity in Frontal region.
• But confounding factors denote that learning disability also
shows similar result.
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96. CONTROVERSIAL WAVE FORMS
RELEVANT TO PSYCHIATRY
• Fourteen and six per second positive spike:
– Age related change in wave form ,
– some psychiatric phenomena are though to be associated,
– etiology presumed to be closed Bain injury or infection.
• Rhythmic mid temporal discharges:
– 1/3rd to ½ patient showed rhythmic mid temporal
discharges
– Associated with anxiety and somatization.
– Some studies demonstrate behavioral discontrol and
autonomic phenomena.
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97. CONTROVERSIAL WAVE FORMS
RELEVANT TO PSYCHIATRY
• Benign Epiletiform transients of sleep:
• Low-voltage sharp negative or biphasic waves
• some time alternate between right to left hemisphere.
• Associated with vegetative symptoms.
• Six per second spike and wave:
• Also called phantom wave
• Low amplitude waves difficult to recognize
• Associated with impulsivity and vegetative symptoms.
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98. Take Home Message
EEG is simple, noninvasive and inexpensive
investigation.
It can be used for screening as well as
predicting outcome of many neurological and
psychiatric disorders.
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