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Karakis, Ioannis

0000-0001-5122-7211

Mayo Clinic

Department of Neurology, Emory University School of Medicine, Atlanta, Georgia, USA.

Citations 7

Accuracy of the rapid‐response electroencephalography's Automated Seizure Burden Estimator: A follow‐up validation study of version 8 ( AccuRASE II )
Sheikh, Zubeda , Fong, Michael W K , Dhakar, Monica B. , Fang, Wei , Ayub, Neishay , Bacic, Janine , Haider, Hiba A. , Foreman, Brandon , Gilmore, Emily J. , Mizrahi, Moshe , Osman, Gamaleldin , Sheikh, Zubeda B , Dhakar, Monica B , Molino, Janine , Karakis, Ioannis , Schmitt, Sarah E , Osman, Gamaleldin , Yoo, Ji Yeoun , Hirsch, Lawrence J , Haider, Hiba A , Ayub, Neishay , Gilmore, Emily , Foreman, Brandon , Karakis, Ioannis , Yoo, Ji Yeoun , Hirsch, Lawrence J.

Epilepsia | June 25, 2026 | Volume: No volume available | Issue: No issue available | Pages: No page available

10.1002/epi.70352 Get It

Abstract Objective Ceribell Inc.'s point‐of‐care electroencephalographic (EEG) system and artificial intelligence‐based Automated Seizure Burden Estimator (ASBE; ClarityPro) have US Food and Drug Administration clearance for diagnosing electrographic status epilepticus (ESE). The AccuRASE study using ASBE version 6 (V6) showed high negative predictive value (NPV) but limited sensitivity and positive predictive value (PPV) at certain thresholds. Version 8 (V8) is the updated algorithm trained with additional EEG samples. Methods We tested V8 on the previously used rapid‐response EEG test dataset (not used to train V8). Sensitivity, specificity, PPV, and NPV were compared against blinded expert annotations. ESE, ESE and possible ESE (ESE/pESE), electrographic seizures (ESz), and Esz with highly epileptiform patterns (Esz/HEPs) at burden thresholds of >1%, >10%, >20%, >50%, and >90% were analyzed. Additionally, we evaluated the built‐in ESE and ESE/pESE alerts (≥90% over 5 min, ≥20% over 1 h, or ≥10 continuous minutes of seizure). Results V8 showed 100% sensitivity at lower thresholds (>10%–20%) for ESE (V6 .86), without a specificity loss (V8 .9 vs. V6 .85), and retained NPV (V8 1.0 vs. V6 .99). Sensitivity at 50% threshold was .86 for ESE (V6 .71), and specificity was .94 (V6 .91); PPV for ESE was 30% for ESE and 80% for ESE/pESE. The specificity for ESE remained high for 90% burden (V8 .96, V6 .97) but the sensitivity dropped (.29 vs. V6 .43). Sensitivity was lower for ESz/HEPs (.54 → .44 at >10% threshold), although the algorithm is not designed to detect HEPs. Built‐in alert analysis showed significantly improved sensitivity for ESE (.57 → .86); specificity and NPV remained high (>.94). Significance ASBE V8 showed meaningful improvements in sensitivity, continued excellent NPV, and improved built‐in alert accuracy for ESE and ESE/pESE. The best seizure burden threshold for ruling out ESE now is 20% (vs. 10% with V6) and that for ruling in ESE/pESE with reasonable certainty is 50% (vs. 90% with V6).
Noise in the diagnosis of epilepsy by experts
Nascimento, Fábio A. , McLaren, John R. , Zhao, Wei, Katyal, Roohi , Sheikh, Irfan S., Kong, Wan Yee , Aljaafari, Danah , Barot, Nirav, Benbadis, Selim, Friedman, Daniel, Gavvala, Jay R. , Halford, Jonathan, Hogan, R. Edward, Kaplan, Peter W., Matthews, Rebecca, O'Donovan, Cormac, Stefan, Rampp, Sirven, Joseph I , Tatum, William O. , Williams, Jonathan, Yacubian, Elza Márcia, Yuan, Doyle, Beniczky, Sándor, Sibony, Olivier, Westover, M. Brandon, Benbadis, Selim R. , Westover, M. Brandon , McLaren, John R. , Benbadis, S , Karakis, Ioannis , Schuele, Stephan , Sirven, Joseph, Tatum, William O , Beniczky, Sándor , Westover, M Brandon , Gavvala, Jay R , Nascimento, Fábio A , Barot, Nirav, Friedman, Daniel , Halford, Jonathan J. , Hogan, R Edward , Kaplan, Peter W., Karakis, Ioannis , Maheshwari, Atul , Matthews, Rebecca, O'Donovan, Cormac, Williams, Jonathan, Yacubian, Elza Márcia, Yuan, Doyle , Sibony, Olivier

Epileptic Disorders | January 20, 2026 | Volume: 28 | Issue: 2 | Pages: 457-469

10.1002/epd2.70181 Get It

Abstract Objective To measure the relative levels of signal and noise in expert diagnosis of epilepsy. Methods Twenty multinational epileptologists independently reviewed 50 vignettes of adult and pediatric patients presenting with suspected seizure(s) on two separate occasions with a ≥30‐day washout period. Experts provided a diagnosis of epilepsy or non‐epilepsy based on clinical information and, if requested, routine EEG and neuroimaging data. Cases had an established clinical diagnosis of epilepsy or non‐epilepsy based on capture of habitual paroxysmal events on video‐EEG or long‐term clinical follow‐up. Experts' judgments were analyzed to decompose variability into different sources: signal (objective differences between cases), level noise (experts' bias toward over/under‐diagnosis), pattern noise (experts' idiosyncratic reactions to specific case features), and occasion noise (inconsistency across occasions). Results The probability of an expert making a different diagnosis for a given case on two different occasions was 16%. The probability of two different experts making a different diagnosis for the same case was 26%. Signal (case “difficulty”) accounted for 66–69% of total variation, with 31–34% attributable to noise. Level noise was the largest contributor in the absence of EEG/neuroimaging results (23%), while pattern noise dominated when test results were available (24%). Occasion noise contributed relatively little (1%) but was still sufficient to cause diagnostic reversals in 16–22% between occasions. Significance The degree of noise in expert diagnosis of epilepsy is substantial, stemming primarily from physicians' idiosyncratic interpretations of case features and variable dispositions toward over‐ or under‐diagnosis. Strategies to improve reliability are needed, including standardized data collection protocols and structured decision algorithms. For “difficult cases,” where expert reliability and accuracy are lowest, our findings support current clinical practice which favors early referral for video‐EEG monitoring over reliance on diagnostic anchoring. This diagnostic pathway may become more accessible with advances in EEG technology (e.g., wearable devices) and artificial intelligence.
Annual Course / From Then to Now: The Evolving Spectrum of Epilepsy Care
McKee, Heather , Ovalle, Adriana Bermeo, Giambarberi, Luciana , Lekoubou, Alain , Rossetti, Andrea O., Alexopoulos, Andreas V. , Tripathi, Manjari, Beniczky, Sándor, Wright, Sukhvir , King-Stephens, David, Richardson, R. Mark, Ali, Amza , Ruiz, Andrés Rodríguez, Rodríguez, Andrés , McKee, Heather Ravvin , Block, Cady, Muh, Carrie R , Karakis, Ioannis , Bui, Esther , Alexopoulos, Andreas V , Wright, Sukhvir K , Lekoubou, Alain , Rossetti, Andrea O. , Block, Cady K. , Habela, Christa Whelan , Beniczky, Sándor , VanHaerents, Stephen , Muh, Carrie R. , King‐Stephens, David , Richardson, Robert Mark , Karakis, Ioannis , Bui, Esther

Epilepsy Currents | December 22, 2025 | Volume: No volume available | Issue: No issue available | Pages: No page available

10.1177/15357597251406694 Get It

Understanding the evolution of clinical tools and models of care is fundamental to advancing the field of epilepsy. The 2025 American Epilepsy Society Annual Course examined the expanding spectrum of epilepsy care through the integration of multispecialty collaboration, innovative diagnostic modalities, and surgical and nonsurgical therapeutic interventions. The course underscored significant global advancements in epilepsy research and practice. This comprehensive review synthesizes key educational insights from the program, offering a critical perspective on the ongoing transformation of epilepsy care.
sEEG ‐guided responsive neurostimulation to treat neocortical epilepsy: A multicenter retrospective study of the efficacy and safety of depth electrode‐mediated neuromodulation
Sadeghzadeh, Sina , Purger, David , Bhanot, Priya , Johnson, Noriah , Schonfeld, Ethan , Abikenari, Matthew , Jain, Bhav , Aronson, Joshua P. , Drees, Cornelia , Fisher, Tiffany , Gray, Tyler E. , Ojemann, Steven , Sather, Michael D., Skidmore, Christopher , Yoo, Ji Yeoun , Graber, Kevin , Halpern, Casey H. , Buch, Vivek , Parker, Jonathon J. , Drees, Cornelia , Gray, Tyler E , Hines, Kevin , Karakis, Ioannis , Quraishi, Imran H , Raslan, Ahmed M , Wu, Chengyuan , Yoo, Ji Yeoun , Buch, Vivek , Skidmore, Christopher , Barbosa, Daniel A. N. , Huang, Yuhao , Park, Jay J. , Gerrard, Jason L. , Ghatan, Saadi , Jobst, Barbara C. , Karakis, Ioannis , Willie, Jon T , Wu, Chengyuan

Epilepsia Open | November 18, 2025 | Volume: 11 | Issue: 1 | Pages: 146-161

10.1002/epi4.70180 Get It

Abstract Objectives Pivotal trials have established the effectiveness of the Responsive Neurostimulation System (RNS® System) in treating focal epilepsy. In clinical trials, depth leads were primarily used to treat mesial temporal seizure onsets while cortical strip leads were used to treat neocortical seizure onsets. Here, we systematically analyze the safety and efficacy of stereoelectroencephalography (sEEG)‐guided depth leads to provide responsive stimulation to neocortical gray matter. Methods Patients were stratified as strong responders (>median cohort seizure reduction %), weak responders (>0% and ≤median cohort seizure reduction %), and anti‐responders (≤0%) based on percent seizure reduction at 1 year post‐implant (1‐Y). Pre‐operative T1‐weighted magnetic resonance imaging and post‐operative computed tomography images were merged, and the Euclidean distance between the sEEG epileptic focus (sEEG‐EF) and the nearest RNS System depth lead contacts was calculated. Results A total of 87 depth leads were implanted in 55 patients across neocortical brain regions. The median reduction in clinical seizures improved from 66.7% at 1‐Y to 77.5% at long‐term follow‐up (LTFU: 2.35 ± 0.95 years), with 10 patients (18.2%) achieving complete seizure freedom. Seven patients (12.7%) experienced six serious adverse events. At 1‐Y, shorter Euclidean distance between the sEEG‐EF and RNS System depth leads predicted improved seizure outcome in strong responders ( β = −0.84, p = 0.008) but not in weak responders ( β = 0.21, p = 0.9) or anti‐responders ( β = −20.34, p = 0.11). At LTFU, there was no significant relationship between Euclidean distance and seizure reduction in strong responders ( β = 0.77, p = 0.18), weak responders ( β = 2.05, p = 0.54), or anti‐responders ( β = 0.24, p = 0.99). Exploratory analyses at 1‐Y showed nominal associations between older age ( ρ = 0.32), longer epilepsy duration ( ρ = 0.27), and non‐mesial temporal sEEG‐EFs and greater seizure reduction; however, none survived Bonferroni correction (adjusted α = 0.0027; all post‐correction p > 0.0027), and no associations were observed at LTFU. Significance In this series, neocortical depth leads for RNS therapy had favorable safety and efficacy and proximity to the sEEG‐EF drove initial outcomes for strong responders to RNS therapy. Plain Language Summary In this multi‐center study, patients with difficult‐to‐treat seizures received brain‐responsive stimulation using a device called responsive neurostimulation (RNS), which delivers small electrical pulses to reduce seizures. We focused on patients treated with electrodes placed in the brain's outer regions (the neocortex) and guided by a mapping procedure called sEEG. On average, patients had their seizures cut by two‐thirds after one year and by more than three‐quarters with longer follow‐up, with about one in five becoming seizure‐free. The treatment was safe, and closer electrode placement to the seizure source helped explain early—but not long‐term—improvements.
New Antiepileptic Drugs: Focus on Ezogabine, Clobazam, and Perampanel
Rudzinski, Leslie A., Velez‐Ruiz, Naymee , Gedzelman, Evan , Mauricio, Elizabeth A. , Shih, Jerry J. , Karakis, Ioannis , Mauricio, Elizabeth A. , Karakis, Ioannis

Journal of Investigative Medicine | June 2, 2016 | Volume: 64 | Issue: 6 | Pages: 1087-1101

10.1136/jim-2016-000151 Get It

Ezogabine, clobazam, and perampanel are among the newest antiseizure drugs approved by the Food and Drug Administration between 2011 and 2012. Ezogabine and perampanel are approved for adjunctive treatment of partial epilepsy. Perampanel is also approved for adjunctive treatment of primary generalized tonic–clonic seizures. Ezogabine and perampanel have novel mechanisms of action. Ezogabine binds to voltage-gated potassium channels and increases the M-current thereby causing membrane hyperpolarization. Perampanel is a selective, non-competitive 2-amino-3-(3-hydroxy-5-methyl-isoxazol-4-yl)propanoic acid receptor antagonist, which reduces neuronal excitation. Clobazam has been used worldwide since the 1970s and is approved for adjunctive treatment of seizures associated with Lennox-Gastaut syndrome. Clobazam is the only 1,5-benzodiazepine currently in clinical use, which is less sedating than the commonly used 1,4-benzodiazepines. Phase III multicenter, randomized, double-blind, placebo-controlled trials demonstrated efficacy and good tolerability of these 3 new antiepileptic drugs. These drugs represent a welcome addition to the armamentarium of practitioners, but it remains to be seen how they will affect the landscape of pharmacoresistant epilepsy.