Neurosurgery for Neuropsychiatric Disorders Flashcards
What is a frontal leucotomy?
Cutting white matter tracts from frontal lobes to rest of brain
What is a transorbital lobotomy?
Form of leucotomy not requiring anaesthetic/septic technique
Ice pick into orbital of eye - into frontal lobe - white matter tract transection
What is stereotactic neurosurgery?
Use pnemoencephalography - introduce air into CSF - use X-rays to see brain and guide instrument - reach lesion target
Which neurosurgical method is used now for severe OCD?
Anterior capsulotomy
What are the main symptoms of OCD?
Obsessional thoughts
Resulting anxiety
Compulsions - stereotyped, repeated rituals - temporarily relieve anxiety - until obsessions build up again
What are the usual treatment for OCD?
High SRI dose - augment with antipsychotics
Combined SRI and CBT/ERP
What is a anterior capsulotomy?
Lesioning anterior capsule
Which areas are targeted in DBS for OCD?
Ventral capsule and ventral striatum
Only ventral striatum
Subthalamic nucleus (emotional and cognitive processing regions)
Which DBS target area has the highest response rate for OCD?
Ventral capsule and ventral striatum
Which DBS target area best improves mood in OCD?
Ventral capsule and ventral striatum - more than STN
Which DBS target area best improves OCD symptoms?
VC/VS and STN equally effective
Which DBS target area best improves cognitive flexibiltiy?
STN - more than VC/VS
Which brain areas are thought to be involved in OCD circuitry?
Orbitofrontal cortex
Anterior cingulate cortex
Striatum
Which cortico-striatal-thalamic circuit is important in OCD and what is its role?
Limbic circuit
Connects limbic cortex with hippocampus and amygdala
Emotional stimulus mediation
What is the proposed cognitive network in OCD and what controls cognitive flexibility?
Tracts from STN-VTA - via multiple regions
Impaired cognitive flexibility linked to decreased connectivity between lateral OFC and striatum
What is the proposed affective network in OCD and what is its role?
Tracts from VC-VTA - via multiple regions
Influences areas mediating emotional processing
Is DBS of OCD circuitry excitatory or inhibitory?
Inhibitory
How is OCD circuit metabolism and activity altered in OCD?
Increased metabolism in certain brain areas - circuit hyperactivity
