DBS

Question 1

Phase III DBS trials:

Answer 1

• PD, MDD, Dystonia, Epilepsy OCD, TS

Question 2

General DBS mechanisms

Answer 2

> Pathway activation
àIncreased release glu / DA in projection areas
Depolarization block (hyperpolarization or
neurotransmitter depletion)
- No production of AP’s
Neural jamming
- Neural network disruption by additional nerve impulses
Net inhibition of the network
- Preferential activation inhibitory neurons (GABA, adenosine)
- Properties network itself when driven at high rate

Question 3

DBS - striatal DA release?

Answer 3

• DA release appears to remain stable with DBS, but DA metabolite levels have been shown to increase

Question 4

How may DBS in the STN work?

Answer 4

• STN stim may lead to a repair in striatal DA functioning with re-establishement of the balance between the direct and indirect pathway
• DBS may restore network oscillation
  patterns