QuestionSBA
QuestionChoice
The weakness and sensory loss of a right-sided stroke would affect the left side, as the primary motor and somatosensory cortices control the contralateral side of the body. Sudden-onset weakness and loss of sensation to the lower, not upper, limb would be more consistent with anterior cerebral artery stroke.
10027094
d
Right anterior cerebral artery stroke
QuestionChoice
Bell’s palsy is a lower motor neuron paralysis of the facial nerve. This would present with weakness or paralysis of facial muscles, including those of the forehead. It would not affect the arm or result in aphasia.
10027092
b
Bell's palsy
QuestionChoice
Anterior cerebral artery strokes may present similarly to middle cerebral artery strokes. A commonly used differentiator between the two is the area affected by the weakness and loss of sensation. According to the cortical homunculus, the area of primary motor and somatosensory cortices supplied by the anterior cerebral artery represents the lower limb, so sudden-onset weakness and loss of sensation to the lower limb would be more consistent with anterior cerebral artery stroke.
10027093
c
Left anterior cerebral artery stroke
QuestionChoice
Posterior cerebral artery strokes are commonly associated with visual defects, due to infarction of the visual cortex in the occipital lobe. The weakness and sensory loss of a right-sided stroke would affect the left side, as the primary motor and somatosensory cortices control the contralateral side of the body.
10027095
e
Right posterior cerebral artery stroke
QuestionChoice
The left middle cerebral artery (MCA) supplies the parts of the motor and somatosensory cortices representing the right arm and face, so infarction here causes upper motor neuron signs in these areas. The forehead muscles are spared in unilateral upper motor neuron lesions, such as left MCA stroke. This is due to their bilateral cortical representation, meaning that the alternative pathway can still provide innervation. Aphasia most commonly occurs due to damage to either Broca’s area, Wernicke’s area or both- these areas are supplied by the left MCA. The patient also has multiple risk factors for ischaemic stroke such as hypertension, hypercholesterolaemia and type 2 diabetes mellitus.
10027091
a
Left middle cerebral artery stroke
Concept
Chapter
2693
3743
Ischaemic Stroke
Topic
141
Neurology
17816
A 67-year-old man with a history of hypertension, hypercholesterolaemia and type 2 diabetes mellitus presents to the emergency department with sudden-onset weakness and loss of sensation to his right arm and face, excluding his forehead. He is also demonstrating aphasia.

What is the most likely pathophysiology underlying this presentation?
a