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A 70 year old man has progression of his Parkinson's disease tremor that is unresponsive to medications. A stereotactic operation is scheduled. To alleviate the tremor, the needle should be placed in which of the following locations?

A- Substantia *****
B- Inferior olivary nucleus
C- Globus pallidus
D- Frontal lobe of the cortex
E- Cerebellar hemisphere
 

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the answer is C

parkinsons disease result from degeneration of dopaminergic neurons in the substantia *****. However these neurons provide dopamine which act via D1 receptors to activate the direct pathway through striatum to inhibit Globus pallidus interna, this leads to cortical motor excitation. Absence of this dopamine mediated cortical excitation can result in the symptoms of PD.
The stereotactic needle will ablate Gobus pallidus interna leading to cortical excitation.
 

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Yes, I agree

parkinsons disease result from degeneration of dopaminergic neurons in the substantia *****. However these neurons provide dopamine which act via D1 receptors to activate the direct pathway through striatum to inhibit Globus pallidus interna, this leads to cortical motor excitation. Absence of this dopamine mediated cortical excitation can result in the symptoms of PD.
The stereotactic needle will ablate Gobus pallidus interna leading to cortical excitation.
Yes, I agree the surgical targets of stereotactic Parkinson's treatment are either the globus pallidus or the subthalamic nucleus or the thalamus to decrease the tremor portion of the disease.
 
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