Background: Epilepsy surgery is an established treatment for drug-resistant focal epilepsy (DRFE) that results in seizure freedom in about 60% of patients. Correctly identifying an epileptogenic lesion in magnetic resonance imaging (MRI) is challenging but highly relevant since it improves the likelihood of being referred for presurgical diagnosis. The epileptogenic lesion’s etiology directly relates to the surgical intervention’s indication and outcome. Therefore, it is vital to correctly identify epileptogenic lesions and their etiology presurgically. Methods: We compared the final histopathological diagnoses of all patients with DRFE undergoing epilepsy surgery at our center between 2015 and 2021 with their MRI diagnoses before and after presurgical diagnosis at our epilepsy center, including MRI evaluations by expert epilepsy neuroradiologists. Additionally, we analyzed the outcome of different subgroups. Results: This study included 132 patients. The discordance between histopathology and MRI diagnoses significantly decreased from 61.3% for non-expert MRI evaluations (NEMRIs) to 22.1% for epilepsy center MRI evaluations (ECMRIs; p < 0.0001). The MRI-sensitivity improved significantly from 68.6% for NEMRIs to 97.7% for ECMRIs (p < 0.0001). Identifying focal cortical dysplasia (FCD) and amygdala dysplasia was the most challenging for both subgroups. 65.5% of patients with negative NEMRI were seizure-free 12 months postoperatively, no patient with negative ECMRI achieved seizure-freedom. The mean duration of epilepsy until surgical intervention was 13.6 years in patients with an initial negative NEMRI and 9.5 years in patients with a recognized lesion in NEMRI. Conclusions: This study provides evidence that for patients with DRFE—especially those with initial negative findings in a non-expert MRI—an early consultation at an epilepsy center, including an ECMRI, is important for identifying candidates for epilepsy surgery. NEMRI-negative findings preoperatively do not preclude seizure freedom postoperatively. Therefore, patients with DRFE that remain MRI-negative after initial NEMRI should be referred to an epilepsy center for presurgical evaluation. Nonreferral based on NEMRI negativity may harm such patients and delay surgical intervention. However, ECMRI-negative patients have a reduced chance of becoming seizure-free after epilepsy surgery. Further improvements in MRI technique and evaluation are needed and should be directed towards improving sensitivity for FCDs and amygdala dysplasias.

Background/ Objectives; After negative results of the SAMMPRIS-trial the indication for endovascular treatment of atherosclerotic intracranial artery stenosis (ICAS) was widely restricted. It was the aim of our study to report whether intracranial arterial percutaneous transluminal angioplasty and stenting (PTAS) as ultima ratio therapy is still effective and safe enough. Methods: Between February 2011 and June 2019, 63 consecutive patients with and without emergent large vessel occlusion (ELVO) who received PTAS for symptomatic ICAS in the anterior or vertebrobasilar circulation were in-cluded in our study. Results: 32 patients had ELVO. In the remaining 31 patients, a known ICAS was treated with PTAS either because of recurrent stroke despite aggressive medical therapy with dual antiplatelet inhibition (n=24) or due to progressive hemodynamic ischemia (n=7). Stenting was successful in all 63 cases. Successful reperfusion was achieved in 94% of ELVO patients. Complications with new neurologic deficits, including dissection, subarachnoid hemorrhage, in-tracerebral hemorrhage (PH2), and stent-thrombosis, were seen in 5 ELVO patients (16%). At discharge, neuro-logical status improved in 16 patients (50%) and deteriorated in 7 patients (22%). In-hospital mortality happened in 5 of 32 ELVO cases (16%), all of them had lesions in the vertebrobasilar circulation. Regarding non-ELVO cases, two patients (6%) developed new neurologic deficits due to perforator strokes. There was no in-hospital mortality in this group. Conclusion: Even in unfavorable situations with acute atherothrombotic occlusions or recurrent strokes under ag-gressive medical therapy of known ICAS, PTAS remains a treatment option with reasonable efficacy and tolerable complication rates.

Background/Objectives: After the negative results of the SAMMPRIS trial, the indication for endovascular treatment of atherosclerotic intracranial artery stenosis (ICAS) was widely restricted. It was the aim of our study to report whether intracranial arterial percutaneous transluminal angioplasty and stenting (PTAS) as ultima ratio therapy is still effective and safe enough. Methods: Between February 2011 and June 2019, 63 consecutive patients with and without emergent large vessel occlusion (ELVO) who received PTAS for symptomatic ICAS in the anterior or vertebrobasilar circulation were included in our study. Results: A total of 32 patients had ELVO. In the remaining 31 patients, a known ICAS was treated with PTAS either because of recurrent stroke despite aggressive medical therapy with dual antiplatelet inhibition (n = 24) or due to progressive hemodynamic ischemia (n = 7). Stenting was successful in all 63 cases. Successful reperfusion was achieved in 94% of ELVO patients. Complications with new neurologic deficits, including dissection, subarachnoid hemorrhage, intracerebral hemorrhage (PH2), and stent thrombosis, were seen in five ELVO patients (16%). At discharge, neurological status improved in 16 patients (50%) and deteriorated in 7 patients (22%). In-hospital mortality happened in 5 of 32 ELVO cases (16%), and all of them had lesions in the vertebrobasilar circulation. Regarding non-ELVO cases, two patients (6%) developed new neurologic deficits due to perforator strokes. There was no in-hospital mortality in this group. Conclusions: Even in unfavorable situations with acute atherothrombotic occlusions or recurrent strokes under aggressive medical therapy of known ICAS, PTAS remains a treatment option with reasonable effectiveness. This should be balanced against other treatment options, taking into account the complication rate, which is not negligible.