1. Is there evidence of pyramidal system (i.e., upper motor neuron or corticospinal tract) involvement in this case. If so, what is the level or location of that involvement? What side of the central nervous system is involved? Is this involvement part of the patient’s acute neurologic problem or part of her prior neurologic events?
Yes.
Left corticospinal tract. It is difficult to precisely localize the level of involvement because the patient had sustained a series of left-sided infarcts in the previous 4 years. However, at least one of these strokes was probably a left middle cerebral artery (MCA) infarct, resulting in her global aphasia.
Prior problem.
2. How would you classify this patient’s involuntary left-sided movements? Are these movements part of her acute neurologic problem or part of her past neurologic events?
Hemiballismus.
Her acute neurologic problem.
3. Indicate the specific structure involved by the pathologic process, including the side of involvement.
Right subthalamic nucleus.
4. In general, what type of pathologic process do you think is involved with this patient’s acute neurologic problem?
Vascular. Ischemic infarct of right subthalamic nucleus due to an occlusion of one of the central (penetrating) branches of the posterior cerebral artery (posteromedial group)
5. What diagnostic procedure(s) would you undertake at this point?
This case occurred before MRI scanning was available. Her CT scan did not reveal any new acute infarcts.
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