Viyana 8. Dünya Psikiyatri Kongresi Sempozyumu

Electrical brain activity following magnetic stimulation as recorded with high-resolution QEEG

Presented in the 8th World Congress of Psychiatry in Vienna in July 2th, 2005.

(A symposium called ‘Brain Stimulation Techniques in Psychiatry and Electrophysiology’. Chair: Bilgen Taneli, Co-chair: Mark George, Other speakers: David Avery, Nevzat Tarhan). Published in The World Journal of Biological Psychiatry, Volume 5-3 (Supplement 1), 2005-July. Electrical brain activity following magnetic stimulation as recorded with high-resolution QEEG Prof. Dr. Nevzat Tarhan rTMS

First TMS capable of delivering a pulse every three seconds (as diagnostic aids for neurologists.)
New machines which can give up to 50 stimuli per second (rTMS)
A non-invasive technique, free of serious side effects, easily modifying activity of specific brain areas

How does rTMS work for brain electrical activity?

rTMS gives short pulses of magnetic energy to Limbic system structures
Small electric charges can cause the neurons to fire or to become active

Ilmoniemi et.al.(1997) were able to measure with QEEG just seconds after electromagnetic pulse

Nashaat et.al (2001),
Nikulin et.al (2003),
Kommsi et.al (2004) have used ongoing rTMS and QEEG Monitoring

Brain electrical activity changes with rTMS

lAcute rTMS induces changes in regional activity throughout the brain
Stimulation intensity is important
Low frequency has a tendency to decrease
High frequency has a tendency to increase

Resynchronization effects

lNormal brain function requires synchronized activity of interconnected brain areas
rTMS may help ‘reset’ the normal synchrony between brain regions (Garcia-Toro et.al. 2001, Avery 2004)

GABA and QEEG

- lGABA increases functional connectivity on QEEG (Benzodiazepine effect)
- GABA decreases with stress
- GABA decreases in plasma and in brain (MRS) of depressed patients
- ECT increases GABA level in depressed patients.
- rTMS: increase ?

State marker improves after treatment

Trait marker doesn’t improve after treatment

‘State markers’ of QEEG being:

lRatio of Alpha waves
Ratio of Delta waves
Hemispheric asymmetry
Alpha/Delta ratio of the frontal area

Acute drug effect in QEEG

lTricyclic Antidepressant drugs: Alpha, Theta, Delta
Antipsychotic drugs :Theta and Delta waves
Antianxiety drugs :beta
Cognitive activator drugs : Alpha
SSRI drugs: Alpha (Itil 1989)

The Response to drug treatment in depression

•Delta waves: good response,
Alpha and Beta waves: good response,
Unchanged QEEG: bad response. (Kendler)

The Distribution of Brain waves in QEEG after 10 sessions of rTMS (preliminary findings)

According to HAM ScoresHAM Scores and QEEG after 10 sessions of rTMS “An interpretation”

lAll patients showed 30-50% treatment response
In Alpha increases group, HAM improvement was greater
In no changes group, HAM improvement was minimal
More verification, and MEG studies, are necessary

Pregnancy and rTMS (Case Study I)

lOne case (I.D., 32 years)
She had serious non-psychotic Chronic Major Depression.
She used antiepileptic and antidepressant drugs.
She became pregnant during treatment.
She wanted to continue the pregnancy.

Pregnancy and rTMS (Case Study II)

lFirstly, we stopped her using the antidepressant drugs
We applied 40 sessions of rTMS to her.
Every session was 25 Hz. and 1000 pulses.
Now, she has a healthy baby.
After birth, rTMS was continued.

Frequency of seizures

lWe applied rTMS at approximately 15,000 sessions in two years
In every session, rTMS was applied at 25 Hz
In most cases, 1000 pulses were applied in every session
Grandmal seizures were observed only in 3 cases.(3 /15,000)

25 Hz, 1 Pulses, 50% Power
25 Hz, 1 Pulses, 100% Power
25 Hz, 3 Pulses, 100% Power
5 Hz, 10 Pulses, 50% Power, Duration 1.8 sec
5 Hz, 10 Pulses, 75% Power, Duration 1.8 sec
5 Hz, 10 Pulses, 100% Power, Duration 1.8 sec
25 Hz, 50 Pulses, 50% Power, Duration 1.9 sec
25 Hz, 50 Pulses, 75% Power, Duration 1.9 sec
25 Hz, 50 Pulses, 100% Power, Duration 1.9 sec

Scientific Inspiration

One day, in 1990 at a London Hospital in an elevator, a passenger was giggling. A magnetic stimulation had been applied to his head. It was a neuro-diagnostic motor test, for thumb jerk
Dr. Mark George observed and was astonished by this situation. He suspected that magnetic fields could move much more than the thumb.
The story of magnetic therapy in psychiatry started like this.

Paylaş

Yazar: Nevzat TARHAN

Görüntülenme:

Güncellenme Tarihi:14 Ağustos 2011Yayınlanma Tarihi:02 Temmuz 2005

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