Neuromodulation

Question 1

Where did the whole idea behind convulsive therapy come from?

Answer 1

Jauregg’s giving malaria to patients with neurosyphilis. Fevers / convulsions appeared to help things. Chemically induced seizures helped patients with catatonic schizophrenia when nothing had ever helped before.

Question 2

Why was ECT first developed?

Answer 2

A more reliable and safe way to induce seizures vs. malaria / chemicals.

Question 3

Does ECT work well for depression?

Answer 3

Yes, actually.

The meta-analysis cited is weird though… as a lot of the studies listed are from before the advent of SSRIs.

Question 4

Indications for ECT? (8 are listed…)

Answer 4

MDD
bipolar
schizophrenia and schizoaffective disorder
catatonia
neuroleptic malignant syndrome
sever autism
status epilepticus
Parkinson's disease

Question 5

Why don’t you want to use ECT in people with unstable CV disease?

Answer 5

ECT causes release of catecholamines -> sympathetics -> tachycardia/arrhythmias

Question 6

Why do you have to be careful with ECT when patient has past skull fracture or craniotomy?

Answer 6

Can cause burns.

Question 7

Why don’t you want to use ECT for patients with cognitive impairment?

Answer 7

It can make that impairment worse.

Question 8

For which personality disorder do you not want to use ECT?

Answer 8

Borderline

Question 9

Hand-waving plausible mechanisms for ECT activity?

Answer 9

Changes in monaminergic, glutaminergic, and glutaminergic neurons. Maybe increased BDNF.

Question 10

One mechanism by which ECT may help depression that is supported by imaging?

Answer 10

“Reduced functional connectivity” in left dlPFC. (correlation… not proven to be causal)

Question 11

Why pre-oxygenate when using ECT?

Answer 11

Increased metabolic demand during induced seizure?

Question 12

What kind of anesthesia is used for ECT?

Answer 12

Short-acting IV anesthesia, often propofol.

Plus a muscle relaxant.

Question 13

What are 3 electrode placements in order of least effective/fewest side effects to most effective/most side effects?

Answer 13

Right unilateral
Bifrontal
Bitemporal

Question 14

What about the waveform?

Answer 14

Square, short, wave pulses of AC current are better than sine waves.

Question 15

How common is relapse (for all conditions) after ECT?

Answer 15

Very common, but can be mitigate with pharmacotherapy +/- maintenance ECT.

Question 16

How does transcranial magnetic stimulation (TMS) contrast from ECT?

Answer 16

TMS allows you to stimulate specific parts of cortex by inducing a current in it.

Question 17

Main advantage of TMS over ECT? (3)

Answer 17

No cognitive effects.
Doesn’t cause seizure.
Safer.

Question 18

Things that TMS might treat that ECT doesn’t?

Answer 18

Pain syndromes, tinnitus, ADHD.

Question 19

Is TMS proven to work for depression?

Answer 19

Technically, yes, but the significance was borderline.

Question 20

3 factors shown by meta-analysis to influence the effectiveness of TMS for depression?

Answer 20

Duration, intensity, # of pulses.

Question 21

Advantages of Magnetic Seizure Therapy over ECT?

Answer 21

More focal, fewer cognitve side effects, less post-ictal confusion.
(Dr. Bhati says it’s likely not as effect as ECT…)

Question 22

When is vagal nerve stimulation (VNS) indicated? Major drawback?

Answer 22

For depression that has not responded to 4 or more drugs.

Takes months for full effect.

Question 23

What area of the brain might the vagal nerve stimulation hit?

Answer 23

the orbitofrontal cortex.

Question 24

How does deep brain stimulation (DBS) contrast from VNS? Which areas of the

Answer 24

Electrodes actually go into brain.

Ant. cingulate, ventral striatum, nucleus accumbens.

Question 25

Indications for DBS? (2 are approved)

Answer 25

Severe OCD, essential tremor and epilepsy.

Use in depression, obesity, addiction, etc. is being studied

Question 26

What’s the major risk of DBS?

Answer 26

Somewhat obviously, intracerebral hemorrhage.

Question 27

Why was area 25 of the cingulate gyrus targeted in DBS for depression? Did it work?

Answer 27

Because this area changed from hyperactive to less active in people successfully treated for depression with CBT or fluoxetine.
It worked in an open-label study, but that doesn’t tell you much.