Objective: To elucidate factors affecting the developmental outcome of cryptogenic West syndrome.
Study design: Medical records of 32 patients, who were followed-up regularly for more than 1 year, were reviewed for clinical features: treatment lag, electroencephalography findings, and seizure evolution. Those features were compared between the normal outcome group (12 patients) and the delayed outcome group (20 patients). The outcomes were determined at the average age of 8.6 +/- 4.7 years.
Results: The duration from onset to any treatment of the delayed group was longer than that of the normal group (P < .05). Evolution of electroencephalographic findings showed that paroxysmal discharges reappeared in frontal regions more frequently in the delayed group than in the normal group (P < .05). In the delayed group, other types of seizure except for spasms occurred more commonly than in the normal group (P < .05). More patients of the delayed group evolved to focal epilepsy than those of the normal group (P < .05).
Conclusions: Shorter treatment lag might be associated with a favorable outcome in cryptogenic West syndrome. Reappearance of paroxysmal discharges in the frontal regions and evolution to other types of seizure may be associated with undetectable lesions in the frontal regions.