Transient
ischemic attacks involving vertebral-basilar vessels
TIAs in the vertebral-basilar
territory can produce a number of different problems reflecting the many functions
of the brainstem. Because the basilar artery is a single midline vessel with branches
supplying both sides of the brainstem, these TIAs can produce bilateral or
unilateral motor and sensory findings.
The most common signs and symptoms reported in brainstem TIAs are dizziness or
vertigo and nausea. These complaints probably result from damage to vestibular
system structures found throughout much of the brainstem. However, episodes of
dizziness or nausea are not uniquely associated with TIAs (nor is every TIA producing
dizziness caused by blockage of vertebral-basilar vessels). Accurate diagnosis
and localization of vertebral-basilar territory TIAs requires other brainstem
findings in addition to 'dizziness.'