ABSTRACT
OBJECTIVE: To demonstrate the utility of accurate clinical and electroencephalographic characterization of provoked cataplexy spells in the diagnosis of narcolepsy. METHODS: Four individuals, three with suspected and one with known narcolepsy, were clinically assessed during split-screen, video polysomnographic monitoring sessions after cataplectic events were induced by emotional provocation. RESULTS: The subjects experienced a total of nine cataplectic-like events, one occurring spontaneously (sleep paralysis) in association with a hypnagogic hallucination. During all events, the patients appeared to be sleeping with polysomnographic rapid eye movement sleep patterns, but when questioned they were able to give appropriate verbal responses. The diagnosis of narcolepsy was substantiated in all cases using standard overnight polysomnograms and multiple sleep latency tests. CONCLUSION: The diagnosis of narcolepsy can be greatly enhanced by documenting cataplexy with thorough clinical assessment and demonstration of typical rapid eye movement sleep patterns during provoked spells in the course of polysomnographic monitoring sessions.
Subject(s)
Cataplexy/diagnosis , Narcolepsy/diagnosis , Adolescent , Adult , Cataplexy/physiopathology , Electroencephalography , Electromyography , Electrooculography , Electrophysiology/methods , Emotions , Female , Humans , Male , Middle Aged , Narcolepsy/physiopathology , Paralysis , Sleep, REM , Video Recording , WakefulnessABSTRACT
OBJECTIVE: To polysomnographically determine, using split-screen electroencephalographic-video analysis, the cause of violent sleep-related activity in a patient whose differential diagnosis includes sleep walking (somnambulism), pavor incubus (adult night terrors), nocturnal seizures, psychogenic wandering, and rapid eye movement sleep behavior disorder. SETTING: The patient was referred to the University of Iowa, Department of Neurology Sleep Disorders Center, Iowa City, from the local community to evaluate a history of violent dreams associated with injury. The subject presented with a subdural hemorrhage that was discovered with magnetic resonance imaging. OUTCOME: The diagnosis of rapid eye movement sleep behavior disorder was confirmed after a characteristic spell of violent behavior, with an associated dream, was captured polysomnographically.
Subject(s)
Cerebral Hemorrhage/etiology , Dreams , Mental Disorders/complications , Sleep Wake Disorders/complications , Violence , Accidental Falls , Aged , Humans , Male , Polysomnography , Sleep Wake Disorders/physiopathology , Sleep, REMABSTRACT
The clinical diagnosis of narcolepsy often depends on the coexistence of pathologic sleepiness and cataplectic attacks. We present a case of narcolepsy unequivocally diagnosed after daytime, split-screen, video-polysomnographic monitoring captured a prolonged cataplectic event during which the patient was coherent, conversant, and in electroencephalographic rapid eye movement sleep.
Subject(s)
Catalepsy/diagnosis , Narcolepsy/diagnosis , Adult , Catalepsy/complications , Catalepsy/physiopathology , Electroencephalography , Humans , Male , Narcolepsy/complications , Narcolepsy/physiopathology , Polysomnography , Sleep, REM/physiology , Television , Time FactorsABSTRACT
When two potentials having large amplitude differences are simultaneously recorded, the large amplitude potential contaminates the small amplitude response. The small, early potentials generated by this contamination resemble far-field potentials. Although scalp-recorded SEP was contaminated by waves similar to the peripheral potential, peak latencies and wave form were not identical. Experiments simulating the recording situation verified the presence of "cross-talk." Capacitive coupling would shift peaks and alter the wave forms. Other possible mechanisms for the cross-talk and methods of minimizing it are offered. One should be cautious interpreting the results when potentials of large amplitude differences are simultaneously recorded.
