Long-Term Outcomes of Corpus Callosotomy in Adult Patients with Drug-Resistant Epilepsy; Results from a Single Neurosurgical Center in Mexico

Objective Corpus callosotomy (CC) is a commonly indicated palliative surgery for Drug-Resistant Epilepsy (DRE). While younger age at the time of surgery is a well-established positive prognostic factor, there is limited evidence on long-term outcomes in adult patients with DRE. A study that evaluates seizure control at various follow-up points is necessary to better understand the outcomes of CC. Methods In this retrospective longitudinal cohort we included adult CC patients operated by our institution’s epilepsy surgery service between 1993 and 2023. We compiled epilepsy etiology, preoperative seizure frequency, and postoperative seizure outcomes at < 1-year follow-up, 1–3 years follow-up, and > 3 years of follow-up. Our outcomes were seizure freedom and response rate (50% frequency decrease from preoperative). Results We analyzed data from 63 patients. The most common indication for CC was DRE due to Lennox-Gastaut Syndrome. Median seizure frequency had a significant decrease from preoperative (70 seizures per month [spm], IQR = 16–210) to the 1-year follow-up (4 spm, IQR = 0–20, p = < 0.0001), 1–3 years follow-up (8 spm, IQR = 1–30, p = < 0.0001), and > 3 years of follow-up (7 spm, IQR = 2.25-30, p = < 0.0001). Seizure freedom at one year postoperative decreased from 25.4–9.7% at 1–3 years (p = 0.032), while the overall response rate of our sample remained consistent, being 81% at 1-year follow-up and 70% at the long-term follow-up (p = 0.20). Conclusion We identified that CC effectively decreases seizure frequency in adult patients with DRE. The reduction of seizure frequency after CC remained consistent after the first postoperative year. Prospective clinical trials are needed to better understand the long-term outcomes of CC in adults.