Chapter 24: Stroke & Neurovascular Disorders
A 64-year-old patient presents with the sudden onset of impaired vision. On examination, you find a right homonymous hemianopia without any other neurologic deficits. What is the most likely vascular territory involved?
A. Left middle cerebral artery (MCA)
C. Left posterior cerebral artery (PCA)
C. This patient has a right visual field cut. Although some of these fibers traverse the left middle cerebral artery territory, other neurologic deficits would be expected to be present. An isolated visual field cut is typical of a posterior cerebral artery territory infarction.
The patient in Question 1 is noted to have an irregularly irregular rhythm on cardiac auscultation. Based on this finding, what is the most likely mechanism for the stroke?
A. Occlusion of a small, perforating vessel in the thalamus
B. Embolism of a clot from the left atrium of the heart
C. Symmetric hypoperfusion of both hemispheres
D. Intracerebral hemorrhage from thrombosis of the superior sagittal sinus
B. An irregularly irregular heart rhythm is suggestive of atrial fibrillation, a common stroke mechanism. In these patients, the stroke is thought to originate from an embolism from the appendage of the left atrium.
A 48-year-old man is brought to the emergency department after collapsing at home with left hemiparesis. Computed tomography reveals an intraparenchymal hemorrhage in the right basal ganglia with intraventricular extension. What is the most likely etiology for his hemorrhage?
A. Hypertensive hemorrhage
C. Superior sagittal sinus thrombosis
D. Herpes simplex virus encephalitis
A. This is a typical location for a hypertensive hemorrhage. Cerebral amyloid angiopathy typically affects older patients and causes lobar hemorrhage. Although a venous sinus thrombosis can cause hemorrhage, they are more often cortical, and thrombosis of the superior sagittal sinus would not affect the deep nuclei. Herpes simplex virus preferentially affects the temporal lobe rather than the deep nuclei.
A 24-year-old woman presents with 3 days of headache and blurred vision to the emergency department. She has papilledema on examination, and magnetic resonance venography demonstrates a parietal infarction with loss of flow in the superior sagittal sinus. What is the best acute therapy for this condition?