Expert Note Case 2.

Limp Arm

This patient had not one but a series of TIAs initially caused by temporary ischemia in the arm and hand area of the right motor and perhaps somatosensory cortex, both supplied by carotid branches. TIAs in carotid artery territory typically produce varying combinations of:

• one-sided limb weakness, clumsiness, or paralysis
• one-sided numbness (paresthesias, or loss of sensation)
• some problem with language (production or comprehension)
• some problem articulating words, often described as 'slurring' words (dysarthria)
• partial or complete homonymous visual field defects (often not described by patients)

The patient's well-established collateral circulation involving her ophthalmic artery suggests that carotid stenosis had been steadily progressing over a period of time. Usually plaque ulceration or rupture, which encourages thrombus formation, occurs when there is significant stenosis of the carotid artery. Surgical removal of accumulated plaque by carotid endarterectomy has been shown to significantly decrease the risk of stroke in patients like this.