BLINK REFLEX IN PATIENTS WITH WALLENBERGS SYNDROME

Knowledge of the neural circuits involved in Wallenberg's syndrome (WS ) is incomplete. Study of the blink reflex (BR) in patients with WS ca n help in reaching a better understanding of the physiopathology under lying clinical symptoms and may help in the prediction of clinical out come. We evaluated the BR in response to supraorbital nerve electrical stimuli in 20 patients with WS. All patients were studied within the 1st week after onset of symptoms, and 10 of them were also studied rep eatedly during a follow-up period of 3-12 months. At the first examina tion the long latency bilateral responses (R2 and R2c) to stimulation of the supraorbital nerve of the affected side were absent in 11, dela yed in 4, and normal in 5 patients. At follow-up, there was a normaliz ation of the BR in all patients who had absent or delayed responses at the first examination except for one patient whose responses remained absent at the 9th month. Late responses elicited on the side of the l esion by stimulation of the non-affected supraorbital nerve were norma l in all but one patient. This patient died from cardiorespiratory arr est within the 1st month of the illness. One patient with normal BR re sponses also died in the acute phase. The BR is abnormal in most patie nts with acute WS and tends to normalize in a mean period of 7 months. BR pattern is not a predictor of early fatal complications in patient s with this syndrome.