Amnesia may be a presenting complaint for an arterial dissection.
Amnesia may be transient global or anterograde.
Clinical clues may include (Colotto et al):
(1) hypotension OR hypertension OR difference in blood pressure between the left and right arm
(2) syncope
(3) facial pallor
(4) chest, neck, back or lumbar pain
(5) fever
(6) unexplained leukocytosis
(7) increase in plasma D-dimer concentration
(8) unexplained increase in serum creatinine concentration
Spiral CT angiography or other imaging study is needed to make the diagnosis.