Epilepsia, 44(6):870–871, 2003 Blackwell Publishing, Inc. C  2003 International League Against Epilepsy Original Letter Late Language Transfer in Patients with Rasmussen Encephalitis ∗ Tobias Loddenkemper, ∗ Elaine Wyllie, ∗ David Lardizabal, †Lisa D. Stanford, and ‡William Bingaman Departments of ∗ Neurology, †Neuropsychology, and ‡Neurosurgery, The Cleveland Clinic Foundation, Cleveland, Ohio, U.S.A. Language can transfer to the right hemisphere in pa- tients with early left-sided brain injury (1,2). Rare cases with acquired left hemisphere lesions and language trans- fer after age 9 years have been reported (1,3,4). The pos- sibility of language transfer in adolescent patients may influence decision making in epilepsy surgery and may alter concepts of language development and plasticity. We report two adolescents with initially left- hemispheric language dominance proven by intracarotid amobarbital testing (IAT) who developed right-sided lan- guage between 9 and 15 years and between 12 and 14 years, respectively. Language was impaired in both pa- tients because of Rasmussen chronic encephalitis begin- ning at 8 and 11 years, with improvement after left hemi- spherectomy at ages 14 and 15 years. Case one, a right-handed 8-year-old boy, had phar- macologically intractable right clonic seizures associated with left frontocentral EEG seizures. Bilateral IAT at age 9 revealed left hemisphere language dominance. Re- peated magnetic resonance imaging (MRI) showed pro- gressive left hemispheric atrophy and increased left tem- porooccipital signal on T 2 sequences. At age 15 years, right-sided epilepsia partialis continua and hemiparesis developed. Handedness shifted from right to left. A re- peated IAT at that time showed right-sided language rep- resentation. Left functional hemispherectomy was per- formed. Histopathology was consistent with Rasmussen encephalitis. Postoperatively, no impaired language func- tion was noted. Rare right facial clonic seizures were well controlled. Neuropsychological testing showed language improvement as compared with presurgical assessment (Table 1). Case two, a right-handed 11-year-old girl, had right clonic seizures and left frontocentral EEG seizures. Re- Accepted February 8, 2003. Address corresponding and reprint requests to Dr. T. Loddenkemper at Department of Epilepsy and Sleep Disorders, The Cleveland Clinic Foundation, 9500 Euclid Ave, S-51, Cleveland, OH 44195, U.S.A. E-mail: loddent@ccf.org peated MRIs demonstrated progressive left-hemispheric volume loss and hyperintensity on T 2 -weighted images. IAT at 12 years and 8 months showed left hemisphere lan- guage. Handedness shifted from right to left. The family initially declined left hemispherectomy because of con- cerns regarding language function. Steroids and plasma- pheresis were tried instead, without effect. She was read- mitted at age 13 years and 10 months with right-sided epilepsia partialis continua, dysphasia, right hemipare- sis, dehydration, and inability to swallow. Immediate left functional hemispherectomy led to seizure freedom. Histopathology was typical of Rasmussen encephalitis. Postoperatively, language was slow, but she could com- municate. Neuropsychological assessment demonstrated improved verbal performance as compared with preoper- ative assessment (Table 1). Only seven patients with Rasmussen encephalitis have been reported with apparent interhemispheric transfer of language after age 9 years. Transfer was assessed by neuropsychological means, showing initial language dete- rioration after hemispherectomy and progressive improve- ment over time in five patients (1), by late IAT show- ing right hemisphere language dominance at the time of surgery (4), and by functional MRI (fMRI) in one pa- tient (3).We add the first patients with late language trans- fer, who had initial left hemisphere language dominance proven by IAT early in the illness. Dominant hemispherectomy after age 9 years in pa- tients with Rasmussen chronic encephalitis does not necessarily produce lasting aphasia, even if IAT ini- tially demonstrated left language dominance. Early hemi- spherectomy also may prevent impending bilateral hemi- spheric involvement of the disease after prolonged duration (5) and early death due to uncontrolled seizures with epilepsia partialis continua and generalized status epilepticus (6). Acknowledgment: T.L. was supported by Innovative Medi- zinische Forschung, WWU M¨ unster (FoeKz. LO 610101) and 870