[Diagnosis of narcolepsy-cataplexy: importance of continuous recording in ambulatory EEG. Report of 20 cases].

Ambulatory EEG (A-EEG) allows longterm polygraphic recording over 24 hours or more and proves to be particularly useful in the diagnosis of narcolepsy-cataplexy (N/C). We performed A-EEG using the Medilog 9000-8 channel system over a total of 36 24-hour periods in 20 consecutive N/C patients and recorded an average of 3.5 daytime sleep episodes, of which 2.2 were with SOREMP, AND 21 evening SOREMP (58%). A MSLT was performed using A-EEG in 16 cases. Continuous A-EEG proved to be more informative than the MSLT, and may represent a valid alternative to the classic continuous polygraphic recordings performed in the sleep lab, that are more cumbersome and costly. Although a full-night polysomnographic recording is still necessary whenever other sleep disorders are suspected in association with N/C, A-EEG is a first-line, practical method for the confirmation of N/C, which remains a clinical diagnosis.