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Background: In the pre-surgical evaluation of people with focal epilepsy and a normal MRI, Morphometric Analysis Program v2018 (MAP18) aids in detecting visually inconspicuous focal cortical dysplasia (FCD). We investigated the impact of MRI scans with reduced signal-to-noise ratio (SNR) and spatial resolution (SR) on FCD detection by MAP18, aiming to improve the chances of achieving seizure freedom through epilepsy surgery., Methods: Thirty MRI scans with the identified lesion using MAP18 radiologically confirmed as FCD by a neuroradiologist, were retrospective analysed. SNR and SR were artificially reduced in ten steps, and their impact on MAP18 outcomes was assessed using multilevel analysis., Results: There was a significant effect after reducing SR and SNR for z-score and volume of the FCD cluster, the total number of detected clusters, and volume of these clusters. After SNR reduction, there was also a significant effect for z-score of the total number of detected clusters. FCD became undetectable by MAP18 after six steps of SR reduction (voxel size 2.8 × 2.8 × 2.8 mm³) and after two steps of SNR reduction., Conclusions: This exploratory study suggests that reduced SR and SNR negatively affect FCD detection with MRI post-processing (MAP18). The MAP18 evaluator should screen MRI quality before post-processing, particularly for scans with significant visual noise or voxel sizes of 2.8 × 2.8 × 2.8 mm³ and upwards, as repeating a low-quality MRI scan is less burdensome than the adverse effects of continued seizures due to failure to detect FCD., Competing Interests: Declaration of competing interest None of the authors has any conflict of interest to disclose., (Copyright © 2024 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.)

Purpose: The eradication of epileptogenic lesions (e.g. focal cortical dysplasia) can be used for treatment of drug-resistant focal epilepsy, but in highly eloquent cortex areas it can also lead to a permanent neurological deficit. In such cases the neuromodulation effect of low-dose high-precision irradiation of circumscribed lesions may represent an alternative therapy., Method: A total of 10 patients with eloquent localized lesions causing pharmacoresistant focal epilepsy were prospectively identified. After informed consent, six patients agreed and were treated with risk adapted low-dose radiosurgery (SRS) or hypofractionated stereotactic radiotherapy (hfSRT). Comprehensive data concerning treatment modalities and outcome after short-term follow up (mean=16.3 months) were prospectively collected and evaluated., Results: From the six patients, two patients were treated with hfSRT (marginal dose 36 Gy) and four with SRS (marginal dose 13 Gy). Clinical target volume (CTV) ranged from 0.70 ccm to 4.32 ccm. The short-term follow-up ranged from 6 to 27 months. There were no side effects or neurological deficits after treatment. At last available follow-up two patients were seizure-free, one of them being off antiepileptic drugs. The seizure frequency improved in one and remained unchanged in three patients., Conclusion: Treatment of eloquent localized epileptogenic lesions by SRS and hfSRT showed no adverse events and an acceptable seizure outcome in this small prospective patient series. The relatively short-term follow-up comprises one of the study's drawbacks and therefore a longer follow-up should be awaited in order to evaluate the neuromodulation effect of the treatment. These preliminary results may however justify the initiation of a larger prospective trial investigating whether focused low-dose stereotactic irradiation could be an option for lesions in eloquent brain areas., (Copyright © 2016 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.)

Unlabelled: Patients with epilepsy may have additional psychogenic non-epileptic seizures (PNES). It has been suggested that PNES are more common if patients with epilepsy are female, develop epilepsy later in life and have right-sided brain lesions. We examine whether these or other physical factors affect the risk of PNES in patients with epilepsy in a controlled study., Methods: Ninety consecutive patients with PNES and concurrent epilepsy (PNES+E group) and 90 consecutive patients with epilepsy alone (epilepsy group) were compared with regard to the variables sex, age at onset of epilepsy, epilepsy type (focal/generalised), location and lateralisation of epileptogenic zone, aetiology of epilepsy, interictal epileptiform potentials, magnetic resonance imaging (MRI) abnormalities, neuropsychological (NPS) deficits and intelligence quotient (IQ)., Results: Female sex (P<0.001), abnormal visual memory (P=0.012), global NPS impairment (P=0.029), and low IQ category (P=0.005) were associated with a higher risk of PNES. Other variables did not differ between the groups., Conclusions: In patients with epilepsy, female sex, poor visual memory or global neuropsychological underperformance and low IQ are associated with an increased risk of PNES. MRI changes, epileptiform EEG abnormalities and location of epileptogenic zone do not show a predilection for one hemisphere.