Neurological Manifestations of Glutamic Acid Decarboxylase Autoimmunity in Indian Patients.

Objective: To study the neurological manifestations of glutamic acid decarboxylase (GAD 65) autoimmunity in Indian patients. Methods: Retrospective study conducted in a tertiary care referral hospital in South India. Patients who tested positive for GAD 65 antibodies from February 2013 to July 2019 were included. Results: We identified 922 patients who underwent GAD 65 testing, of which 81 tested positive (8.78%) [mean age 55.42 years (SD 17.39, range 9-86 years, median age 57 years)]. Males (n = 47) outnumbered the females (n = 34). All the GAD values measured were <5000 IU/ml. There were 34 cases (42%) of atypical parkinsonism (16/34, 47% fulfilled the diagnostic criteria for autoimmune atypical parkinsonism) in our series forming the most common group with GAD 65 positivity, followed by autoimmune encephalitis (8 cases, 9.88%). Men were more affected with atypical parkinsonism (22/34; 64.70%), stiff person syndrome (2/3; 66.66%), and neuropathy (4/7; 57.1%) while women were more with autoimmune encephalitis (6/8; 75%). Eighteen (22.6%) had underlying autoimmunity (three had type 1 diabetes mellitus). Six (7.4%) had underlying neoplasm. Thirty-three out of 43 patients responded to immunotherapy (76.74%). Five had spontaneous improvement. Conclusion: Glutamic acid decarboxylase65 antibody values were much lower in our study population. Male-dominant autoimmunity was seen unlike that in Western literature. The most striking was the high preponderance of atypical parkinsonism in GAD 65-positive patients. We also found that GAD 65 positivity is a useful marker for a positive response to immunotherapy in suspected autoimmune neurological syndromes irrespective of their titers.

Cerebrospinal fluid indices as predictors of treatment response in autoimmune encephalitis.

BACKGROUND: Cerebrospinal fluid (CSF) indices reflecting intrathecal antibody production and blood-brain barrier impairment are not routinely assessed in patients with autoimmune encephalitis (AE). We aimed to study CSF indices and their association with the prognosis of AE. METHODS: This retrospective cohort study conducted at Amrita Institute of Medical Sciences (AIMS), Kochi, India, included 60 patients aged more than 18 years with definite/probable/possible AE admitted to the Department of Neurology from August 2016 to November 2021. We introduced a classification of treatment response based on modified Rankin Scale change over time and treatment modalities. RESULTS: In our cohort of 60 patients (six [10%] seropositive cases), a good rapid treatment response was associated with CSF white blood cell count of more than 4 cells/mm3 (OR, 4.57; 95% CI 1.31-15.96; P = .02) and positive immunoglobulin G (IgG) Local Synthesis (OR, 7.27; 95% CI 1.56-33.86; P = .01). Albumin Index had association with a poor Glasgow Coma Scale score at the nadir of the disease (OR, 1.17; 95% CI 1.01-1.34; P = .04). Similar results were yielded in the seronegative cohort. IgG Local Synthesis appeared to be a strong predictor for good rapid treatment response in both univariate and multivariate (adjusted OR, 28.71; 95% CI 2.12-389.22; P= .01) analysis. Time to immunotherapy was reversely correlated with good response overall (in the cohort with outliers removed [N = 49]: unadjusted OR 0.97, 95% CI 0.95-0.99; P= .01; adjusted OR 0.97; 95% CI 0.95-0.99; P= .008). CONCLUSION: CSF indices reflecting intrathecal antibody production and blood-brain barrier impairment appear to be promising predictors of disease severity and therapeutic response in patients with autoimmune encephalitis.

Improving the accuracy of epileptogenic zone localization in stereo EEG with machine learning algorithms.

The precise identification of the epileptogenic zone (EZ) is paramount in the presurgical evaluation of epilepsy patients to ensure successful surgical outcomes. The analysis of Stereo EEG, an instrumental tool for EZ localization, poses considerable challenges even for experienced epileptologists. Consequently, the development of machine learning (ML)-based computational tools for enhanced EZ localization is imperative. In this investigation, we developed ML models utilizing Stereo EEG from 15 patients, who remained seizure-free (Engel 1 a-d) following EZ resection, over an average follow-up period of 44.4 months. Utilizing Delphos and MNI detectors, spikes and High Frequency Oscillations (HFOs) were identified from Stereo EEG in Resected Zone (RZ) and non-Resected Zone (non-RZ). Linear and non-linear features were estimated from each modality using MATLAB. A total of 27,744 spikes, 7,790 ripples, and 7,632 fast ripples, along with their combinations, were employed to train the ML models. The Gradient Boosting classifier demonstrated the highest prediction accuracy of 98.5% for EZ localization in Mesial Temporal Lobe Epilepsy (MTLE) when trained with features derived from the spike-ripple combination. In the case of Neocortical Epilepsy (NE), the Extra Trees classifier achieved an accuracy of 87.6% when utilizing features from fast ripples. The Random Forest, Extra Trees, and Gradient Boosting algorithms were the most effective for predicting the RZ. Linear features outperformed non-linear features in predicting epileptogenic zones within the epileptic brain. Our study establishes the capability of ML methodologies in localizing epileptogenic zones with high accuracy. Future studies that focus on increasing the training sample size and incorporating more advanced machine learning (ML) algorithms have the potential to significantly improve the accuracy of these models in pinpointing epileptogenic networks. Additionally, implementing this ML approach across multiple research centers would contribute to the broader validation and generalizability of this technique.

Asymmetry index in anatomically symmetrized FDG-PET for improved epileptogenic focus detection in pharmacoresistant epilepsy.

OBJECTIVE: Positron emission tomography (PET) imaging has assumed an essential role in the presurgical evaluation of epileptogenic foci in drug-resistant epilepsy by identifying the hypometabolic cerebral cortex. The authors herein designed a pilot study to test a novel technique of PET asymmetry after anatomical symmetrization coregistered to MRI (PASCOM), utilizing interhemispheric metabolic asymmetry on interictal fluorine 18-labeled fluorodeoxyglucose (FDG)-PET to better localize the epileptogenic zone. METHODS: The authors analyzed interictal FDG-PET scans from 23 patients with drug-resistant epilepsy, mean (± SD) age 20.9 ± 13.1 years old, who had an Engel class I postsurgical outcome while followed up for > 12 months. T1-weighted and FLAIR MRI were used to create a patient-specific, structurally symmetrical template. The asymmetry index (AI) image was computed to detect the cerebral region of hypometabolism using different z-score threshold criteria to optimize sensitivity and specificity. The detected regions were compared with the resection cavity on postoperative MRI using predefined anatomical labels. PASCOM was compared with the visual analysis of FDG-PET by a nuclear medicine consultant blinded to other clinical data (VIS) and visual analysis during multidisciplinary team discussion (MDT). The efficacy of each technique was compared based on a performance score (S), sensitivity, specificity, and correct lateralization of epileptogenicity. RESULTS: The mean S was maximum (1.30 ± 1.23) for AI images when thresholded at z > 4 and retaining the cluster of more than 100 voxels containing the peak AI value (Z4C) with 73.03% sensitivity and 96.43% specificity. The mean S was minimum for VIS (0.27 ± 0.31). The mean sensitivity was maximum for MDT (85.04%) and minimum for Z5C (AI images thresholded at z > 5 and clustered; 59.47%), whereas the mean specificity was maximum for Z5C (97.77%) and minimum for VIS (64.60%). Z3C (AI images thresholded at z > 3 and clustered) and Z4C were able to correctly identify the side of epileptogenicity in all the patients. CONCLUSIONS: The PASCOM technique with a Z4C threshold had a maximum performance score with good sensitivity and specificity in localizing and lateralizing the epileptogenic zone. The described technique outperformed the conventional visual analysis of FDG-PET and hence warrants further prospective verification.

A Multicenter, Cross-Sectional, Observational Study on Epilepsy and its Management Practices in India.

Background: Although epilepsy is a common neurological condition, there is paucity of nationwide data on treatment patterns and sociodemographic and clinical factors affecting treatment decisions in India. Objective: To assess clinical profiles, usage pattern of antiepileptic drugs (AEDs), and seizure control among patients with epilepsy in India. Methods: This was a cross-sectional, observational, multicenter study on adult patients with epilepsy who were on AEDs for at least six months before enrollment. Data were collected from patient interviews and medical records. Results: Out of 800 enrolled patients, a majority (69.0%) had generalized onset seizure in the six months before enrollment. The median age at epilepsy onset was 20.0 (1.0-64.0) years; 40.0% of the patients were females, 48.5% were married, 99.1% were literate, and 67.0% belonged to the lower or upper-middle socioeconomic class. Overall, 459 patients (57.4%) received AEDs as combination therapy. Most patients received levetiracetam (37.0%), sodium valproate (18.5%), carbamazepine (17.3%), or phenytoin (13.8%) as monotherapy, and clobazam (59.7%), levetiracetam (52.9%), carbamazepine (26.4%), sodium valproate (24.8%), or phenytoin (24.0%) in combination therapy. Quality of life was comparable for first- and third-generation AEDs. Adverse drug reactions were mostly attributed to dose modification or switching between drugs. No serious adverse drug reactions or new safety concerns were identified. Conclusions: Findings from this large, cross-sectional, observational, multicenter study indicate that first-generation AEDs sodium valproate and phenytoin continued to be used in a substantial number of patients on monotherapy and combination therapy in India, even though an increasing trend toward use of second-generation AEDs was noted in clinical practice.

Localizing epileptogenic network from SEEG using non-linear correlation, mutual information and graph theory analysis.

The key challenge in epilepsy surgery is precise localization and removal of the epileptogenic zone (EZ) from the brain. Localization of the epileptogenic network by visual analysis of intracranial EEG is extremely difficult. In this retrospective study, we used interictal connectivity and graph theory analysis on intracranial EEG to better delineate the epileptogenic zone. Patients who underwent surgery for drug-refractory mesial temporal and neocortical epilepsy were included. Computational measures, such as h2 nonlinear correlation and mutual information, were used to estimate the interdependency of intracranial EEGs. We observed that the Out-Degree, Out-Strength, and Betweenness centrality (graph properties) were the best predictors of EZ. From the results, we also found that graph properties with a normalized value above 0.75 were found to be a useful measure to localize the EZ with a sensitivity of 87.88 and a specificity of 87.13. Our results also validate that frequently occurring types of interictal fast discharges (IFD) with connectivity measures and graph properties can better localize the EZ. We foresee graph theory analysis of interictal intracranial EEG data can help precise localization of EZ for cortical resection as well as in minimally invasive radiofrequency ablation of epileptogenic hubs. Further, prospective validation is required for clinical use.

Statistical asymmetry analysis of volumetric MRI and FDG PET in temporal lobe epilepsy.

PURPOSE: To analyze statistically derived threshold values of volumetric MRI and 18F fluorodeoxyglucose (FDG) PET asymmetry, independent of normative data, for non-invasive detection/exclusion of temporal lobe epilepsy (TLE). METHODS: We retrospectively analyzed amygdalohippocampal volumetry and temporal FDG PET metabolism in 33 patients (age: 29.27 ±â€¯8.56 years) who underwent surgery following Stereo-EEG implantation and had postsurgical seizure freedom lasting >12 months. The temporal lobe epilepsy group and the extratemporal lobe epilepsy (ETLE) group were compared. Percentage volume loss (PVL) was calculated from manually traced amygdalohippocampal volumetry whereas percentage metabolic loss (PML) was calculated from PET using amygdalohippocampal trace and temporal neocortical Brodmann areas (BA) template. RESULTS: Receiver operating characteristic (ROC) curve analysis identified a cutoff hippocampal PVL of 4.21% as the minimum indicating probable hippocampal involvement in seizure onset, with sensitivity of 88.89% and the specificity of 100% (p < 0.001). Region of interest (ROI)-based PML values in PET imaging showed a significant correlation with the presence of TLE in the TLE group of patients and its absence in the ETLE group of patients. Region of interest curve analysis yielded PML cutoffs of 5.77% and 8.36%, respectively, for the hippocampus and BA 38 (temporopolar neocortex) to detect TLE with the sensitivity of 72.7% and specificity of 77.8%. CONCLUSION: We describe statistical thresholds for asymmetry analysis of hippocampal volumetry and FDG PET to improve detection of TLE. These threshold parameters warrant further validation in prospective studies.

Autoimmune parkinsonism with faciobrachiocrural dystonic seizures: a new phenotype of leucine-rich glioma-inactivated 1 (LGI1) autoimmunity.

Extrapyramidal symptoms are seen in patients with leucine-rich glioma-inactivated 1 (LGI1) antibody-positive patients infrequently and this can be successfully treated with immunotherapy. This is a retrospective hospital-based study from 2013 to 2021 at a tertiary care referral hospital in South India. LGI1 antibody-positive cases with Faciobrachio-crural dystonic seizures [FBCDS] were identified by reviewing electronic medical records and Neuroimmunology laboratory register. Clinical and laboratory details and treatment outcomes were analysed. There was a total of 23 patients who were positive for LGI1 antibody. Of these, three cases had FBCDS (2 males, age range 30-76 years). Upon reviewing the records they had additional asymmetric parkinsonian features. All had similar presentations with progressive slowness of activities and gait and later went on to have paroxysmal events of sudden falls with vocalization. Prolonged VEEG monitoring captured the habitual event, which were confirmed to be FBCDS. MRI did not show significant structural abnormalities, CSF showed elevated proteins and normal cell in two and lymphocytic pleocytosis in one, PET scans ruled out malignancy. Of the three patients, two were completely relieved of FBCDS with immunosuppression and there was complete resolution of extrapyramidal features in all. Thus, the patients in our series of FBCDS showed additional features of parkinsonism which responded well to immunotherapy. Involvement of basal ganglia can explain all the manifestations of this phenotype. This series reveals a unique phenotype of the LGI1 antibody.

Outcome following surgery for insulo-opercular epilepsies.

OBJECTIVE: The purpose of this study was to evaluate the clinical outcome in patients with medically refractory epilepsy who had undergone resective or ablative surgery for suspected insulo-opercular epileptogenic foci. METHODS: The prospectively maintained database of patients undergoing epilepsy surgery was reviewed, and all patients who underwent insulo-opercular surgery for medically refractory epilepsy with a minimum of 12 months of postoperative follow-up were identified, excluding those who had insulo-opercular resection in combination with temporal lobectomy. The presurgical electroclinicoradiological data, stereo-EEG (SEEG) findings, resection/ablation patterns, surgical pathology, postoperative seizure outcome, and neurological complications were analyzed. RESULTS: Of 407 patients undergoing epilepsy surgery in a 5-year period at the Amrita Advanced Centre for Epilepsy, 24 patients (5.9%) who underwent exclusive insulo-opercular interventions were included in the study. Eleven (46%) underwent surgery on the right side, 12 (50%) on the left side, and the operation was bilateral in 1 (4%). The mean age at surgery was 24.5 ± 12.75 years. Onset of seizures occurred on average at 10.6 ± 9.7 years of life. Characteristic auras were identified in 66% and predominant seizure type was hypermotor (15.4%), automotor (15.4%), hypomotor (11.5%), or a mixed pattern. Seventy-five percent of the seizures recorded on scalp video-EEG occurred during sleep. The 3T MRI results were normal in 12 patients (50%). Direct single-stage surgery was undertaken in 5 patients, and SEEG followed by intervention in 19. Eighteen patients (75%) underwent exclusive resective surgery, 4 (16.7%) underwent exclusive volumetric radiofrequency ablation, and 2 (8.3%) underwent staged radiofrequency ablation and resective surgery. Immediate postoperative neurological deficits occurred in 10/24 (42%), which persisted beyond 12 postoperative months in 3 (12.5%). With a mean follow-up of 25.9 ± 14.6 months, 18 patients (75%) had Engel class I outcome, 3 (12.5%) had Engel class II, and 3 (12.5%) had Engel class III or IV. There was no statistically significant difference in outcomes between MRI-positive versus MRI-negative cases. CONCLUSIONS: Surgery for medically refractory epilepsy in insulo-opercular foci is less common and remains a challenge to epilepsy surgery centers. Localization is aided significantly by a careful study of auras and semiology followed by EEG and imaging. The requirement for SEEG is generally high. Satisfactory rates of seizure freedom were achievable independent of the MRI lesional/nonlesional status. Morbidity is higher for insulo-opercular epilepsy surgery compared to other focal epilepsies; hence, the practice and development of minimally invasive strategies for this subgroup of patients undergoing epilepsy surgery is perhaps most important.

Quantification of Epileptogenic Network From Stereo EEG Recordings Using Epileptogenicity Ranking Method.

Introduction: Precise localization of the epileptogenic zone is very essential for the success of epilepsy surgery. Epileptogenicity index (EI) computationally estimates epileptogenicity of brain structures based on the temporal domain parameters and magnitude of ictal discharges. This method works well in cases of mesial temporal lobe epilepsy but it showed reduced accuracy in neocortical epilepsy. To overcome this scenario, in this study, we propose Epileptogenicity Rank (ER), a modified method of EI for quantifying epileptogenicity, that is based on spatio-temporal properties of Stereo EEG (SEEG). Methods: Energy ratio during ictal discharges, the time of involvement and Euclidean distance between brain structures were used to compute the ER. Retrospectively, we localized the EZ for 33 patients (9 for mesial-temporal lobe epilepsy and 24 for neocortical epilepsy) using post op MRI and Engel 1 surgical outcome at a mean of 40.9 months and then optimized the ER in this group. Results: Epileptic network estimation based on ER successfully differentiated brain regions involved in the seizure onset from the propagation network. ER was calculated at multiple thresholds leading to an optimum value that differentiated the seizure onset from the propagation network. We observed that ER < 7.1 could localize the EZ in neocortical epilepsy with a sensitivity of 94.6% and specificity of 98.3% and ER < 7.3 in mesial temporal lobe epilepsy with a sensitivity of 95% and specificity of 98%. In non-seizure-free patients, the EZ localization based on ER pointed to brain area beyond the cortical resections. Significance: Methods like ER can improve the accuracy of EZ localization for brain resection and increase the precision of minimally invasive surgery techniques (radio-frequency or laser ablation) by identifying the epileptic hubs where the lesion is extensive or in nonlesional cases. For inclusivity with other clinical applications, this ER method has to be studied in more patients.

Current practices in epilepsy monitoring units (EMU) in India.

AIM: As an initial step to develop guidelines for epilepsy monitoring units (EMUs) appropriate for developing countries, we inquired the existing practices in EMUs in India. METHODS: After checking for the content and face validity as well for clarity, we sent a 52-item online non-anonymized questionnaire to all the 52 EMUs in India. RESULTS: The questionnaire was completed by 51 of the 52 EMUs (98% response rate). The majority of the EMUs are located in major cities and 51% are located in non-governmental corporate hospitals. There are total of 122 prolonged video-EEG monitoring (PVEM) beds in India and 70% EMUs have ≤2 beds. Approximately two-thirds of the EMUs have defined protocols for pre-procedure consent and risk assessment, management of seizure clusters and status epilepticus, continuous observation of patients, and peri­ictal testing. Only one-third of the EMUs have protocols for management of post-ictal psychosis, anti-suffocation pillows, and protected environment within bathrooms. The waiting period for PVEM is more (49.9 ± 101 vs. 4.9 ± 10.9 days; p = 0.04) and mean cost for 3-day PVEM is less (INR 8311 ± 9021 vs. 30,371 ± 17,563; p <0.0001) in public as compared to private hospitals. There was a negative correlation between cost of PVEM and the waiting period (r=-0.386; p = 0.01). Safety practices are similar in public and private hospitals. CONCLUSIONS: Although practices in EMUs in India vary widely, they are comparable to those in developed countries. India has severe shortage of EMUs and long waiting lists for affordable PVEM.

Prognostication of the neurological outcome of tethered cord based on intraoperative neuromonitoring findings: how close can we get?

PURPOSE: To evaluate the correlation of intraoperative neuromonitoring (IONM) data in surgery for tethered cord syndrome (TCS) in children to the neurological outcome at 1-year follow-up. METHODS: 208 consecutive patients operated on for TCS, between January 2011 to February 2020, under electrophysiological monitoring in the Division of Paediatric Neurosurgery, AIMS, Kochi, India, were included. Their preoperative neurological, urological and orthopaedic status were compared with the postoperative status at 1 year follow-up. RESULTS: Our study prospectively collected the IONM data and retrospectively correlated it to the children's neurological outcome on follow-up. Out of 208 children, 28% (n = 59/208) had motor, 35% (n = 73/208) had bladder and 26% (n = 54/208) had bowel disturbances. Postsurgery, at one-year follow-up, 91% (n = 52/57) of the patients who had motor deficits had improvement, 82.3% (n = 51/62) of patients who had bladder deficits showed an improvement, and 88.8% (n = 48/54) with bowel deficits showed improvement. The monitorability for motor and sphincter potentials were 99.4% and 89.3%, respectively. Except for four patients (3 with bladder and 1 with motor worsening), all the patients who were monitorable with no deficits remained intact except for four patients, all the patients who had deficits and were monitorable improved after detethering (at 1 year). Clinical worsening corresponded to those who had a drop in amplitude of baseline TcMEP (n = 4). 18 events showed an increase in amplitude compared to the baseline TcMEP. These patients improved clinically on follow-up (at 1 year). CONCLUSIONS: IONM complements the preoperative clinical details in predicting immediate and long-term outcomes.

Impact of COVID-19 pandemic on epilepsy practice in India: A tripartite survey.

OBJECTIVE: To assess the impact of ongoing COVID-19 pandemic on epilepsy care in India. METHODS: We conducted a three-part survey comprising neurologists, people with epilepsy (PWE), and 11 specialized epilepsy centers across India. We sent two separate online survey questionnaires to Indian neurologists and PWE to assess the epilepsy practice, seizures control, and access to care during the COVID-19 pandemic. We collected and compared the data concerning the number of PWE cared for and epilepsy procedures performed during the 6 months periods preceding and following COVID-19 lockdown from epilepsy centers. RESULTS: The survey was completed by 453 neurologists and 325 PWE. One third of the neurologist reported >50 % decline in outdoor visits by PWE and EEG recordings. The cumulative data from 11 centers showed 65-70 % decline in the number of outdoor patients, video-EEG monitoring, and epilepsy surgery. Working in a hospital admitting COVID-19 patients and use of teleconsultation correlated with this decline. Half of PWE had postponed their planned outpatient visits and EEG. Less than 10 % of PWE missed their antiseizure medicines (ASM) or had seizures due to the nonavailability of ASM. Seizure control remained unchanged or improved in 92 % PWE. Half of the neurologists started using teleconsultation during the pandemic. Only 4% of PWE were afflicted with COVID-19 infection. CONCLUSIONS: Despite significant decline in the number of PWE visiting hospitals, their seizure control and access to ASMs were not affected during the COVID-19 pandemic in India. Risk of COVID-19 infection in PWE is similar to general population.

Contralateral insular epileptogenic hub causing seizure relapse after opercular focal cortical dysplasia surgery and response to radiofrequency thermocoagulation: illustrative case.

BACKGROUND: The reevaluation and management of seizure relapse following resective surgery in magnetic resonance imaging (MRI)-negative pharmacoresistant epilepsy remains a significant challenge. OBSERVATIONS: A 25-year-old right-handed male with medically refractory epilepsy presented with nonlocalizing electroencephalography (EEG) and MRI. Stereo-EEG (SEEG) implantation based on semiology and positron emission tomography imaging revealed a left frontal opercular focus with rapid bilateral insular ictal synchrony. The initial epileptogenic zone was resected and pathologically proven to be type 2A focal cortical dysplasia (FCD). Seizure relapse after 9 months was eventually reinvestigated, and repeat SEEG revealed a secondary epileptogenic focus in the contralateral insula. A novel technique of volumetric stereotactic radiofrequency ablation (vRFA) was utilized for the right insular focus, following which, the patient remains seizure-free for 20 months. He suffered a transient bilateral opercular syndrome following the second intervention that eventually resolved. LESSONS: The authors present clinical evidence to suggest epileptogenic nodes distant from the primary focus as a mechanism for seizure relapse following FCD surgery and the importance of bilateral insular SEEG coverage. The authors also describe a novel technique of minimally invasive vRFA that allows ablation of a larger volume of cerebral cortex when compared to conventional bedside SEEG electrode thermocoagulation.

Epileptic nystagmus due to a large parieto-temporo-occipital multilobar dysplasia.

We report a young female with medically refractory multiple daily seizures since childhood with semiology suggestive of an epileptic nystagmus. She had a large multilobar parieto-temporo-occipital dysplasia and became seizure-free after parieto-temporo-occipital disconnection with preserved visual functions.

Comparison of clinical and electrophysiological characteristics between ictal and cardiac asystole encountered during video-EEG monitoring.

Differentiation between syncope secondary to epileptic seizures and cardiac disease in patients displaying transient loss of consciousness associated with convulsive movements is a diagnostic challenge both for neurologists and cardiologists. In such patients, prolonged video-EEG monitoring not only helps in identifying asystole as the cause of syncope, but also in categorizing asystole as primarily cardiac in origin (cardiac asystole) and secondary to epileptic seizures (ictal asystole). We carried out this study to ascertain the prevalence of asystole in an epilepsy monitoring unit, and to contrast the clinical and electrophysiological characteristics between ictal asystole and cardiac asystole. Through a retrospective search, we identified patients who were shown to have had asystole using a database of patients who underwent prolonged video-EEG monitoring during a 68-month period. We compared the data of 18 consecutive patients; five with ictal asystole and 13 with cardiac asystole, with 121 and 64 events recorded from them, respectively. Of the 10,096 patients who underwent prolonged video-EEG monitoring during the study period, we identified 18 (0.17%) patients with asystole. Cardiac asystole was 2.6 times more frequent than ictal asystole. Older age at onset, heralding symptoms of presyncope, occurrence during wakefulness, and brief duration of the events supported the diagnosis of cardiac asystole. Ictal asystole events were more protracted, and prolonged asystole more frequently occurred in patients with extratemporal seizures compared to temporal lobe seizures. Asystole occurred in only half of the recorded seizures. The accurate categorization of asystole as seizure-related or heart disease-related has huge implications for management strategy and outcome. The necessity of permanent pacemaker implantation is more frequent and urgent in patients with cardiac asystole because of the greater risk of sudden death. Hence, in patients with an ominous diagnosis of cardiac asystole, a thorough cardiac evaluation should surpass neurological evaluation.

Expanding spectrum of contactin-associated protein 2 (CASPR2) autoimmunity-syndrome of parkinsonism and ataxia.

Contactin-associated protein 2 (CASPR2) antibodies are originally associated with Morvan's syndrome and peripheral nerve hyper excitability. Our objective was to study retrospectively the clinical spectrum of CASPR2 antibody-positive patients in our hospital. This is a retrospective observational study. Patients treated at the Amrita Institute of Medical Sciences from May 2013 to April 2016, who were tested positive for CASPR2 antibodies, were included. A total of 1584 samples were tested in the neuroimmunology laboratory during the study period for voltage-gated potassium channel (VGKC) complex antibodies-leucine-rich glioma-inactivated protein 1 (LGI1) and CASPR2 antibodies. Thirty-four were positive for LGI1, 13 were positive for CASPR2, and 7 were for both (total 54-3.4% positivity). Of these 54 cases, 11 were treated in our hospital. Seven were positive for LGI1, three for CASPR2, and one for both. The patient who had both CASPR2 and LGI1 antibody positive had Morvan's syndrome. One patient with CASPR2 had neuromyotonia. The other patient was admitted with status epilepticus with a syndrome of parkinsonism and ataxia. The third patient had encephalopathy and myoclonus with a syndrome of parkinsonism and ataxia. Two of them underwent siddha treatment for other ailments prior to the onset of the disease for other ailments. Our short series shows the expanding spectrum of CASPR2 autoimmunity. Syndrome of parkinsonism and ataxia is an important manifestation of CASPR2 autoimmunity where we can offer a definitive treatment.