Abstracts

RATIONALE: Callosal sections have been used in the treatment of refractory generalized epilepsy in many centers. The use of more extensive callosal sections (maximized callosotomy - MC) has been associated to a better surgical outcome in relation to seizures. This paper compares the neuropsychological effects of MC and more restricted anterior callosal sections (ACS).
METHODS: Eleven normal controls, 11 matched non-operated patients with refractory generalized epilepsies, 6 patients submitted to ACS and 5 submitted to MC were studied. All were submitted to extensive neuropsychological and interhemispheric transfer protocol testing including: WAIS, laterality questionnaire, unimanual motor tasks (associated fingers, stick transfer, tapping, copy, drawing, writing), sensorymotor tests (sequential gestures, reproduction, kinesthesic interhemispheric transfer, praxis), bimanual coordination, simultaneous movements tasks (hands, fingers, tapping), alternating movement tests (hands, fingers, palms), cooperative movement tasks (necklace, buttoning, lacing, stick transfer), somesthesic tests (intra- and inter-hemispheric localization and object, geometric figures and texture comparison), stereognosis and dichotic listening testing. Univariate parametric analysis, Tuckey[prime]s testing, ANOVAS and T-student were employed whenever indicated.
RESULTS: Additionally to the ACS syndrome, patients with MC showed deficits in the interhemispheric transfer of spatial information (p.e., sequential gestures), interhemispheric somesthesic transfer (touch, tactile stimuli) and in dichotic listening testing, that were not noted in patients with ACS.
CONCLUSIONS: The additional neuropsychological deficits noted in patients with MC confirm a clinical-topographical relationship of the callosal fibers as defined in primate anatomical studies in which the posterior corpus callosum has been shown to carry all the somatosensitive and sensorial interhemispheric fibers. Interestingly, despite the additional neuropsychological morbidity, patients with MC were doing very well after surgery, basically due to a dramatic decrease in seizure frequency and a higher (but difficult to measure) level of attention. Except for one patient, subjective quality of life was rated as [dsquote]much better[dsquote] by the family in all of them.