Transient CNS deficits

Abstract

The incidence of transient (<24 hour) neurologic loss was evaluated from a survey returned by 80/87 members of Cornell's Department of Neurology. Transient CNS dysfunction was reported by 25/80 (32%; 95% confidence interval, 21 to 44%). In most (15) only vision was affected, but ten (13%; 6 to 23%) reported nonvisual deficits. In nine of these ten, loss of power, balance, or coordination was noted, sometimes with other symptoms (visual in two), and the tenth subject had speech arrest. Seven of the ten had more than one episode. Episodes in these ten individuals began at age <30 in four, 30 to 34 in five, 35 to 39 in none, and 40 to 44 in one. The reported frequency of migraine was nonsignificantly higher in patients with nonvisual (4/10, 40%) or visual (7/15, 47%) episodes than in respondents without episodes (12/55, 22%; χ₂² = 4.3). Except for inflammatory bowel disease in one respondent, no obvious cause of the nonvisual episodes was evident from follow-up structured interviews. Five of the ten with nonvisual loss and eight of the 15 with isolated visual symptoms thus had no obvious cause for their episodes. Follow-up is limited to a median of 5 years, but none of the 25 has had any residual deficit or chronic neurologic disorder, suggesting that these relatively common episodes of CNS deficit are benign. As new, hyperacute stroke therapies emerge, efforts to distinguish these episodes from true, early strokes will become increasingly important.