To clarify the pathophysiology of nocturnal enuresis and to establish its rational classification and treatment, clinical and electroencephalographic studies were made on 404 enuretic children, including an overnight polysomnographic investigation on 55 cases.
EEG was normal in only 76 cases(18.8%). Background EEG abnormalities were observed in 226 cases(55.9%). This suggested the presence of brain immaturity or dysmaturity in enuretic children. Epileptic discharges were detected in 94 cases(23.3%), but not concomitant with the enuretic events. The epileptic mechanism may not play a primary role in the manifestation of enuresis. Specific EEG patterns of subcortical origin, i.e., 6 c/s wave-and-spike phantom, 14&6 c/s positive epikes, anterior theta burst, and mu rhythm, were detected in as many as 188 cases(46.5%). This indicates the importance of subcortical brain dysfunction in enuresis.
During overnight polysomnographic recordings, 38 enuretic episodes were observed in 30 cases. Twenty eight episodes appeared in light sleep, 8 episodes in deep sleep, but only 2 episodes in REM sleep. According to the arousal response at the time of enuresis, enuretics were properly classified into arousal type(12 cases) and non-arousal type(18 cases). Prognosis was favourable in the cases whose enuresis appeared in light sleep and also in the arousal type enuretics.