No abstract

Surgical resection is highly effective in the treatment of tumor-related epilepsy (TRE) in patients with brain metastases (BM). Nevertheless, some patients suffer from postoperative persistent epilepsy which negatively impacts health-related quality of life. Therefore, early identification of patients with potentially unfavorable seizure outcome after BM resection is important. Patients with TRE that had undergone surgery for BM at the authors’ institution between 2013 and 2018 were analyzed with regard to preoperatively identifiable risk factors for unfavorable seizure outcome. Tumor tissue and tumor necrosis ratios were assessed volumetrically. According to the classification of the International League Against Epilepsy (ILAE), seizure outcome was categorized as favorable (ILAE 1) and unfavorable (ILAE 2–6) after 3 months in order to avoid potential interference with adjuvant cancer treatment. Among all 38 patients undergoing neurosurgical treatment for BM with concomitant TRE, 34 patients achieved a favorable seizure outcome (90%). Unfavorable seizure outcome was significantly associated with larger tumor volumes (p = 0.012), a midline shift > 7 mm (p = 0.025), and a necrosis/tumor volume ratio > 0.2 (p = 0.047). The present study identifies preoperatively collectable risk factors for unfavorable seizure outcome in patients with BM and TRE. This might enable to preselect for highly vulnerable patients with postoperative persistent epilepsy who might benefit from accompanying neuro-oncological expertise during further systemical treatment regimes.

Objective Recently, we showed that resection of at least 27% of the temporal part of piriform cortex (PiC) strongly correlated with seizure freedom 1 year following selective amygdalo‐hippocampectomy (tsSAHE) in patients with mesial temporal lobe epilepsy (mTLE). However, the impact of PiC resection on long‐term seizure outcome following tsSAHE is currently unknown. The aim of this study was to evaluate the impact of PiC resection on long‐term seizure outcome in patients with mTLE treated with tsSAHE. Methods Between 2012 and 2017, 64 patients were included in the retrospective analysis. Long‐term follow‐up (FU) was defined as at least 2 years postoperatively. Seizure outcome was assessed according to the International League against Epilepsy (ILAE). The resected proportions of hippocampus, amygdala, and PiC were volumetrically assessed. Results The mean FU duration was 3.75 ± 1.61 years. Patients with ILAE class 1 revealed a significantly larger median proportion of resected PiC compared to patients with ILAE class 2–6 [46% (IQR 31–57) vs. 16% (IQR 6–38), p = 0.001]. Resected proportions of hippocampus and amygdala did not significantly differ for these groups. Among those patients with at least 27% resected proportion of PiC, there were significantly more patients with seizure freedom compared to the patients with <27% resected proportion of PiC (83% vs. 39%, p = 0.0007). Conclusions Our results show a strong impact of the extent of PiC resection on long‐term seizure outcome following tsSAHE in mTLE. The authors suggest the PiC to constitute a key target volume in tsSAHE to achieve seizure freedom in the long term.

OBJECTIVE Traditionally, patients who underwent elective craniotomy for epilepsy surgery are monitored postoperatively in an intensive care unit (ICU) overnight in order to sufficiently respond to potential early postoperative complications. In the present study, the authors investigated the frequency of early postoperative events that entailed ICU monitoring in patients who had undergone elective craniotomy for epilepsy surgery. In a second step, they aimed at identifying pre- and intraoperative risk factors for the development of unfavorable events to distinguish those patients with the need for postoperative ICU monitoring at the earliest possible stage. METHODS The authors performed a retrospective observational cohort study assessing patients with medically intractable epilepsy (n = 266) who had undergone elective craniotomy for epilepsy surgery between 2012 and 2019 at a tertiary care epilepsy center, excluding those patients who had undergone invasive diagnostic approaches and functional hemispherectomy. Postoperative complications were defined as any unfavorable postoperative surgical and/or anesthesiological event that required further ICU therapy within 48 hours following surgery. A multivariate analysis was performed to reveal preoperatively identifiable risk factors for postoperative adverse events requiring an ICU setting. RESULTS Thirteen (4.9%) of 266 patients developed early postoperative adverse events that required further postoperative ICU care. The most prevalent event was a return to the operating room because of relevant postoperative intracranial hematoma (5 of 266 patients). Multivariate analysis revealed intraoperative blood loss ≥ 325 ml (OR 6.2, p = 0.012) and diabetes mellitus (OR 9.2, p = 0.029) as risk factors for unfavorable postoperative events requiring ICU therapy. CONCLUSIONS The present study revealed routinely collectable risk factors that would allow the identification of patients with an elevated risk of postsurgical complications requiring a postoperative ICU stay following epilepsy surgery. These findings may offer guidance for a stepdown unit admission policy following epilepsy surgical interventions after an external validation of the results.