Callosotomy for Epilepsy After West Syndrome

Abstract

Summary:Purpose: To analyze the results of callosotomy in 17 children with symptomatic generalized epilepsy after West syndrome, according to the different seizure types and surgical procedures, to define selection criteria for candidates to callosotomy.Methods: Callosotomy was performed in two successive stages. Partial callosotomy, anterior in 13 and posterior in three, was followed by completion in 14 cases in all but four patients (complete callosotomy in one stage in one, no completion in three). All patients had clinical, video-EEG, and neuropsychological evaluation before and after each stage of callosotomy, with a mean final follow-up of 4 years.Results: Seizure frequency improved in only two of 13 patients after anterior callosotomy, in none of three after posterior callosotomy, but in nine of 14 after complete callosotomy. After complete callosotomy, spasms disappeared in 80% of the cases, and drop attacks, the most severe ictal event, completely stopped or were dramatically reduced in 90% of the children. One patient no longer had episodes of status epilepticus, and another one acquired the ability to walk after complete callosotomy. From the cognitive viewpoint, nine patients with improved seizure frequency after complete callosotomy also had improved behavior and cognitive functions, but two others experienced speech deterioration after posterior callosotomy at age 11 years and completion of callosotomy at age 16 years.Conclusions: As in other severe generalized epilepsies in childhood, drop attacks provide the best indication for complete callosotomy in patients with previous West syndrome. Because drop attacks can be identifiable by falls only, the previous acquisition of walking should be considered as a key feature for any benefit to be obtained.

Corpus callosotomy in children with intractable epilepsy using frameless stereotactic neuronavigation: 12-year experience at The Hospital for Sick Children in Toronto

“…28 For example, complete corpus callosotomy is more efficient than partial callosotomy in children after West syndrome and with bihemispheric malformations of cortical development. 12,20 Spencer et al 27,28 showed a 68% seizure control rate after complete callosotomy for tonic-clonic seizures and a 57% seizure control rate for tonic seizures. Of the patients in whom anterior callosotomy failed, 60 and 50% had improved seizure outcomes after complete callosotomy for tonic-clonic and tonic seizures, respectively.…”

“…16 It has been suggested that interhemispheric communication is not impaired in cases in which the corpus callosum is absent early in life, whether in the setting of callosal agenesis or due to early callosotomy. 12,15,20 Total callosotomy performed before puberty is not followed by permanent deficits of disconnection syndromes; instead, greater cognitive and social gains may be seen in these children. 14,24 Our results show that patients in both callosotomy groups achieved improved seizure control with 80% of patients in the partial callosotomy group and 87.5% in the complete callosotomy group showing durable long-term atonic seizure control.…”

Corpus Callosotomy in Pediatric Intractable Epilepsy: Microsurgical Technique Implication and Variation

“…Some patients especially younger than 10 years of age do not experience these disconnection syndromes after total callosotomy. (Lassonde, Sauerwein et al 1991;Lassonde and Sauerwein 1997;Rougier, Claverie et al 1997;Sauerwein and Lassonde 1997;Pinard, Delalande et al 1999;Rathore, Abraham et al 2007) The callosal connection and bihemispheric connection are known to be completed at the age of 10 or 11 years. Therefore, early functional absence of callosal connections may lead to development alteration and selective reinforcement of the connection that are normally reinforced in usual circumstances.…”

“…(Tanriverdi, Olivier et al 2009) Pinard et al showed better outcome with total callosotomy in drop attacks among pediatric West syndrome cases. (Pinard, Delalande et al 1999) Most patients being candidates of callosotomy experience multitude of seizure types. Therefore, it is feasible to analyze the outcome by the seizure types.…”

Carbon dioxide laser for corpus callosotomy in the pediatric population

“…[21][22][23] Dandy completed the first case in 1931, when he sectioned the corpus callosum during resection of a cavum cyst in a 4-year-old boy and unintentionally freed him of a seizure disorder.6 A formal description of the procedure came from Van Wagenen and Herrin in 1940, when they reported its use in 10 patients with clinically refractory epilepsy.33 Since then, the procedure has been employed for drop attacks, atonic seizures, tonic-clonic seizures, Lennox-Gastaut syndrome, and recurrent status epilepticus. …”