Prolonged electroencephalographic and video monitoring. An experience froma Chilean hospital

Background: Cerebral activity must be registered for prolonged periods in c ertain clinical situations that are not resolved with conventional electroe ncephalography. Aim: To report the experience with prolonged electroencepha lographic and video monitoring at a Neurology Department, of a Military hos pital in Santiago. Patients and methods: A retrospective analysis of patien ts referred for continuous electroencephalographic and video monitoring bet ween 1991 and 1996. Three hundred thirty six patients, aged 3 months to 60 years old, were studied in the period and in 244, there was information abo ut the diagnosis, treatment and evolution. Results: Monitoring was performe d in an outpatient basis in 84% of subjects and lasted 2 and 7 hours. One h undred ten patients were epileptics, 77 patients had a suspicion of epileps y, 13 patients had possible pseudoseizures and 33 patients had miscellaneou s diagnoses. In 154 patients, electroencephalographs recorded during wakefu lness, somnolence and spontaneous dream, were normal. Intercritical recordi ngs with epileptic activity were obtained in 76 patients and in 30 of these , critical epileptic activity was also recorded, not always associated to c linical manifestations. Unspecific electroencephalographic alternations wer e recorded in 14 patients. Conclusions: Prolonged electroencephalographic a nd video monitoring can be useful for patients with complex neurological pr oblems.