Anterior corpus callosotomy
LITT ablation of the corpus callosum is a safe, feasible, and minimally invasive treatment option for patients with refractory epilepsy, and it may be an attractive alternative for patients unwilling or unable to undergo open surgery 1).
Division of the anterior two thirds of the corpus callosum (CC) minimizes the risk of callosal disconnection syndrome.
May be advantageous over complete callosotomy (controversial).
Total section (anterior commissure to posterior commissure).
Extended callosal section should be considered a good palliative surgical option for suitable candidates. The increase in attention level was as useful as seizure control in improving quality of life of these patients 2).
Case series
Twenty-nine pediatric patients with drop attacks were studied (19 males and 10 females; mean age: 9.9 years). As presurgical factors, the age at surgery, age at seizure onset, age at drop attack onset, sex, hemiparesis, severe mental retardation, electroencephalograph abnormalities, magnetic resonance imaging abnormalities, and 18F positron emission tomography abnormalities were analyzed. All patients had multiple seizure types, including drop attacks, atypical absence seizures, complex partial seizures, tonic seizures, and generalized tonic-clonic seizures. All patients were developmentally impaired and had electroencephalograph results showing marked secondary bilateral synchrony. All patients received an extended, one-stage callosal section, leaving only the splenium intact. The mean follow-up time was 5.2 years. Seizure outcome (cessation of seizures or ≥ 90% seizure reduction) was achieved in 79.3% of patients with drop attacks. The families assessed the overall daily function as improved in 62.1% of the patients, unchanged in 24.1%, and worse in 13.8%. Family satisfaction with callosotomy was achieved in 82.8% of the patients. The majority of the patients had some degree of a transient acute postoperative disconnection syndrome that disappeared within 3 weeks. Postoperatively, patients showed a consistent increase in attention levels. Yang et al. conclude that extended callosal sectioning that leaves the splenium intact should be considered a good palliative surgical option for pediatric patients with drop attacks and that diminishment of epileptic discharge synchrony is a good prognostic sign following callosotomy. They found that the postoperative increase in attention levels was as useful as seizure control in improving the quality of life of these patients 3).
Case reports
Corpus callosotomy is a viable treatment for patients with refractory generalized or multifocal epilepsy, particularly those who have drop attacks. Laser interstitial thermal therapy (LITT) is a minimally invasive surgical option for various intracranial lesions. In this report, we present a 2-trajectory thermal ablation using the NeuroBlate® system (Monteris Medical, MN, USA) for an anterior two-thirds callosotomy in a patient with refractory epilepsy and frequent drop attacks. Adequate ablation of the corpus callosum was confirmed by MRI during the procedure. At the 1-month follow-up, the frequency had decreased from multiple seizures per day to only 3 over the course of 1 month. In addition, he had not suffered any drop attacks or tonic-clonic movements since the procedure. Five months after surgery, seizures had decreased to 1 per month with no drop attacks or loss of consciousness, consistent with an Engel class II outcome. In conclusion, LITT ablation of the corpus callosum is a safe, feasible, and minimally invasive treatment option for patients with refractory epilepsy, and it may be an attractive alternative for patients unwilling or unable to undergo open surgery 4).