Although some children with infantile spasms whose treatment is unsuccessful will eventually carry a diagnosis of LGS, most children with LGS never had infantile spasms in
[infantilespasmsproject.org]
Approximately 17-30% of individuals with LGS have had a prior history of infantile spasms.
[dovemed.com]
Betty Koo, Vigabatrin in the treatment of infantile spasms, Pediatric Neurology, 20, 2, (106), (1999). E.
[doi.org]