Freund, Brin

OBJECTIVE The aim of this study was to compare 3 electrode designs—a novel 22-contact circular grid, standard 6-contact strip, and high-density (HD) grid between 32 and 64 contacts—for the detection of epileptiform activity during awake craniotomy. METHODS This study included patients who underwent functional brain mapping with and without direct electrical stimulation during awake craniotomy. Demographic, clinical, and electrocorticography (ECoG) data were collected. RESULTS A total of 194 patients were included, with 264 instances of electrode use: 113 circular grid, 96 strip electrode, and 55 HD grid. The HD grid (15%) was used less to record ECoG during direct electrical stimulation than the circular grid (80%, p < 0.001) and strip electrodes (69%, p < 0.001). Sporadic interictal epileptiform activity was better detected with circular (45%, p < 0.001) and HD (40%, p = 0.006) grids compared with strip electrodes (16%). Spontaneous seizures were recorded more frequently with the circular grid (16%, p = 0.018) compared with the strip electrode (9.4%) and HD grid (1.8%). Afterdischarges were more frequently detected by the circular grid (69%, p = 0.031) and with circular and HD grids (combined) compared with strip electrodes (67% vs 48%, p = 0.024), at lower median intensity (3 mA vs 5 mA, p < 0.001). Multivariable analyses demonstrated circular grids (p < 0.001) to be more sensitive in detecting spontaneous epileptiform activity than strip and HD grid electrodes, and grids (circular and HD) to be better in recording stimulus-induced epileptiform activity (p = 0.01). CONCLUSIONS This study demonstrates a higher rate of detection of epileptiform activity with circular and standard grids when compared with strip electrodes. The standard HD grid was used less during electrical stimulation, demonstrating the importance of both the number of contacts and design array when considering optimal conditions for ECoG and functional brain mapping.

Abstract Objective: Reading is a complex cognitive process requiring the integration of orthographic, phonological, and semantic information. The visual word form area, located in the ventral occipitotemporal cortex, is critically involved in orthographic decoding, and damage to this region is known to cause alexia. In contrast, the contributions of white matter pathways supporting reading are less well understood. Method: We present a unique neurosurgical case undergoing awake brain surgery for resection of a metastasis in the left occipitotemporal cortex. A tubular retractor was used to access the lesion and during the insertion of the retractor the patient underwent careful, continuous neuropsychological testing, including evaluation of reading. fMRI language mapping and diffusion MRI were performed preoperatively. Postoperative neuropsychological testing was completed two weeks after surgery to assess cognitive outcome. Results: The patient developed an alexia with letter-by-letter reading in real time during insertion of the tubular retractor. Stealth imaging enabled localization of the tubular retractor at the exact onset of the alexia and, by correlating this with tractography, showed that the tubular retractor was in the vertical occipital fasciculus (VOF). Conclusions: We present the first detailed case report linking the VOF to the acute onset of alexia observed intraoperatively during awake brain surgery. We discuss the connectomics of reading and possible contributions of the VOF in reading.

Background: Electroencephalography (EEG) is increasingly used in intensive care units (ICUs), primarily for seizure detection. However, the complex clinical context of critically ill patients and the dynamic ICU environment can complicate interpretation. Purpose: To highlight common pitfalls in ICU EEG interpretation and strategies to distinguish epileptic seizures from mimics. Research Design: Retrospective case series. Study Sample: Five ICU patients undergoing continuous video EEG (cvEEG) for altered mental status, status epilepticus, or paroxysmal events, with underlying conditions including malignancy, autoimmune encephalitis, neuromodulation therapy, and drug-resistant epilepsy. Results: Physiological artifacts, such as non-epileptic rhythmic movements, and device-related artifacts (e.g., pacemakers, ventilators) can mimic epileptic seizures. Plateau waves from elevated intracranial pressure may produce deficits resembling epileptic seizures. Accurate differentiation requires attention to clinical context, EEG features, and video correlation. Maintaining a broad differential and avoiding diagnostic anchoring are also essential to prevent misdiagnosis and unnecessary antiseizure medication therapy. Conclusions: ICU EEG interpretation is challenged by artifacts and non-epileptic movements that mimic epileptic seizures. Awareness of these issues, along with a thoughtful, multidisciplinary approach, is critical for improving diagnostic accuracy and optimizing patient outcomes during cvEEG monitoring.

Abstract Purpose Cenobamate is approved for treating focal epilepsy and has potential for treating tumor‐related epilepsy (TRE) based on potential anti‐tumor effects, though there is little data on efficacy and safety in this patient population. Methods This was a retrospective, multi‐center study of patients with TRE who were prescribed cenobamate as adjunctive treatment between January 2020 and November 2024 at Mayo Clinic in Florida, Minnesota, and Arizona. Drug efficacy was assessed, and factors that were predictive of response to treatment were analyzed. Results A total of 17 patients were included, with 12 being drug resistant. The median seizure frequency for the entire group before starting cenobamate treatment was 12 (IQR = 4–64) per month, and after treatment at last follow‐up was 3 (IQR = 1–15) per month, with an overall 56.3% reduction. Four patients (23.5%) were seizure‐free, and 7 (41.1%) patients were responders (at least 50% seizure reduction). No adverse events were reported for patients on concurrent chemotherapy. Responders had significantly fewer seizures per month compared to non‐responders (5.72 ± 10.29 vs. 27.33 ± 30.17; p = .030). No clinical factors were predictive of responsiveness (or lack thereof) to cenobamate. Conclusions This study demonstrates that adjunctive therapy with cenobamate treatment for TRE is a feasible and potentially effective option. Clinical history, including drug resistance, did not predict drug efficacy. No adverse effects were reported in those treated with chemotherapy. Further studies are needed to validate treatment response and safety.

AbstractObjectiveNeuromodulation is a viable option for patients with drug‐resistant epilepsies. We reviewed the management of patients with two deep brain neurostimulators. In addition, patients implanted with a device targeting the centromedian‐parafascicular (CM‐Pf) nuclear complex supplements this report to provide an illustrative case to implantation and programming a patient with three active devices.MethodsA narrative review using PubMed and Embase identified patients with drug‐resistant epilepsy implanted with more than one neurostimulator was performed. Combinations of vagus nerve stimulation (VNS), deep brain stimulation (DBS), and responsive neurostimulation (RNS) were identified. We provide a background of a newly reported case of an adult with a triple implant eventually responding to CM‐Pf DBS as the third implant following suboptimal benefit from VNS and RNS.ResultsIn review of the literature, dual‐device therapy is increasing in reports of use with combinations of VNS, RNS, and DBS to treat patients with drug‐resistant epilepsy. We review dual‐device implants with thalamic DBS device combinations, functional neural networks, and programming patients with dual devices. CM‐Pf is a new target for DBS and has shown a variable response in focal epilepsy. We report the unique case of 28‐year‐old male with drug‐resistant focal epilepsy who experienced a 75% seizure reduction with CM‐Pf DBS as his third device after suboptimal responses to VNS and RNS. After 9 months, he also experienced seizure freedom from recurrent focal to bilateral tonic–clonic seizures. No medical or surgical complications or safety issues were encountered.ConclusionWe demonstrate safety and feasibility in an adult combining active VNS, RNS, and CM‐Pf DBS. Patients with dual‐device therapy who experience a suboptimal response to initial device use at optimized settings should not be considered a neuromodulation “failure.” Strategies to combine devices require a working knowledge of brain networks.