A 50 year old man was admitted with a sudden inability to feel the left side of his face, left arm and left lower limb. He could speak and he could move all his limbs. He had been diagnosed to have hypertension a few years earlier but he had discontinued his medicines because he felt well. At the time of admission, his blood pressure was 180/106mm Hg and he was conscious and alert. Neurological examination confirmed that he did not have any deficit other than the hemisensory loss. He began improving about 8 hours after admission and within a day, he had recovered his sensations fully. He was diagnosed as having suffered a transient ischemic attack and treated appropriately.
Discussion
Does the diagnosis of a TIA depend only on how soon a patient recovers form a stroke?
It used to be that a diagnosis of TIA was made when a patient recovers from a cerebrovascular event within 24 hours. Now that we know that some of those with a clinical diagnosis of TIA have a visible infarct on brain imaging, the definition of TIA has changed. A TIA, by the new definition, is a transient cerebrovascular event without any visible lesion on brain imaging.
What about those who recover from a stroke within 24 hours but have a visible infarct on brain imaging?
They should be considered as having suffered a minor stroke.
Can this patient be considered to have suffered a lacunar infarct if his brain imaging shows a visible infarct?
Yes. A pure hemisensory deficit is a manifestation of a lacunar infarct. The various clinical manifestations of a lacunar infarct, and their corresponding lesions, are given below (MedTutor acknowledges, with gratitude, the contribution for this answer by medical student Wong Wai Kit):
Pure motor hemiplegia - the affected artery is the lenticulostriate branch of the middle cerebral artery and the lesion is in the internal capsule.
Pure sensory stroke - the affected artery is thalamogeniculate artery which results in a lesion in the ventral posterio-lateral nucleus of the thalamus.
Clumsy hand syndrome/Dysarthria - the affected artery is the penetrating branch of the basilar artery producing a lesion in dorsal Pons.
Ataxic hemiparesis - the affected artery is the penetrating branch of the basilar artery producing a lesion in the ventral Pons.
