Maysaa Basha

Clinical significance and developmental changes of auditory-language-related gamma activity

OBJECTIVE We determined the clinical impact and developmental changes of auditory-language-related augmentation of gamma activity at 50-120 Hz recorded on electrocorticography (ECoG). METHODS We analyzed data from 77 epileptic patients ranging 4-56 years in age. We determined the effects of seizure-onset zone, electrode location, and patient-age upon gamma-augmentation elicited by an auditory-naming task. RESULTS Gamma-augmentation was less frequently elicited within seizure-onset sites compared to other sites. Regardless of age, gamma-augmentation most often involved the 80-100 Hz frequency band. Gamma-augmentation initially involved bilateral superior-temporal regions, followed by left-side dominant involvement in the middle-temporal, medial-temporal, inferior-frontal, dorsolateral-premotor, and medial-frontal regions and concluded with bilateral inferior-Rolandic involvement. Compared to younger patients, those older than 10 years had a larger proportion of left dorsolateral-premotor and right inferior-frontal sites showing gamma-augmentation. The incidence of a post-operative language deficit requiring speech therapy was predicted by the number of resected sites with gamma-augmentation in the superior-temporal, inferior-frontal, dorsolateral-premotor, and inferior-Rolandic regions of the left hemisphere assumed to contain essential language function (r(2) = 0.59; p = 0.001; odds ratio = 6.04 [95% confidence-interval: 2.26-16.15]). CONCLUSIONS Auditory-language-related gamma-augmentation can provide additional information useful to localize the primary language areas. SIGNIFICANCE These results derived from a large sample of patients support the utility of auditory-language-related gamma-augmentation in presurgical evaluation.

Rare sensory and autonomic disturbances associated with vitamin B12 deficiency.

Vitamin B12 deficiency is an important nutritional disorder causing neurological manifestations of myelopathy, neuropathy and dementia. Sub-acute combined degeneration (SCD) with involvement of the posterior columns in the cervical and thoracic cord is a common presentation of this disorder. In this case report, we describe a 43 year old woman with pernicious anemia and myelopathy with atypical clinical features. The patient presented with motor symptoms, a sensory level and bladder dysfunction. She had severe autonomic disturbances including an episode of unexplained bronchospasm, which has not been previously reported as a manifestation of vitamin B12 deficiency. We review the literature regarding these rarely reported features of vitamin B12 deficiency, and discuss aspects of management of this reversible condition. We emphasize the importance of awareness of autonomic disturbances in B12 deficient individuals.

Drug-induced EEG pattern predicts effectiveness of ketamine in treating refractory status epilepticus

Refractory status epilepticus (RSE) can lack overt clinical manifestation and is usually treated with continuous infusion of intravenous anesthetic drugs (IVADs), where the use of continuous electroencephalography (cEEG) is imperative. Ketamine has recently been shown to be effective in the treatment of RSE. We retrospectively review a cohort of 11 patients receiving ketamine as part of their treatment regimen for RSE. We report on the presence of a characteristic EEG rhythm consisting of a generalized archiform theta to beta rhythms (7–20 Hz) appearing after ketamine administration. This pattern was seen in five patients, four of whom achieved successful resolution of RSE. Ketamine‐induced EEG pattern may serve as a biomarker predictive of successful treatment outcome in RSE.

Intracranial EEG analysis in tumor-related epilepsy: Evidence of distant epileptic abnormalities.

OBJECTIVE In patients with tumor-related epilepsy (TRE), surgery traditionally focuses on tumor resection; but identification and removal of associated epileptogenic zone may improve seizure outcome. Here, we study spatial relationship of tumor and seizure onset and early spread zone (SOSz). We also perform quantitative analysis of interictal epileptiform activities in patients with both TRE and non-lesional epilepsy in order to better understand the electrophysiological basis of epileptogenesis. METHODS Twenty-five patients (11 with TRE and 14 with non-lesional epilepsy) underwent staged surgery using intracranial electrodes. Tumors were outlined on MRI and images were coregistered with post-implantation CT images. For each electrode, distance to the nearest tumor margin was measured. Electrodes were categorized based on distance from tumor and involvement in seizure. Quantitative EEG analysis studying frequency, amplitude, power, duration and slope of interictal spikes was performed. RESULTS At least part of the SOSz was located beyond 1.5 cm from the tumor margin in 10/11 patients. Interictally, spike frequency and power were higher in the SOSz and spikes near tumor were smaller and less sharp. Interestingly, peritumoral electrodes had the highest spike frequencies and sharpest spikes, indicating greatest degree of epileptic synchrony. A complete resection of the SOSz resulted in excellent seizure outcome. CONCLUSIONS Seizure onset and early spread often involves brain areas distant from the tumor. SIGNIFICANCE Utilization of epilepsy surgery approach for TRE may provide better seizure outcome and study of the intracranial EEG may provide insight into pathophysiology of TRE.

Mirth and laughter elicited during brain stimulation

There are few reports of laughter and/or mirth evoked by electrical stimulation of the brain. In this study, we present a patient with intractable epilepsy in whom mirth and laughter was consistently produced during stimulation of the left inferior frontal gyrus (opercular part) using stereotactically placed depth electrodes. A review of the literature shows that cortical sites that produce mirth when stimulated are located in the dominant hemisphere close to language areas or cortical negative motor areas.

Characteristics of EEG Interpreters Associated with Higher Inter-rater Agreement.

Purpose: The goal of the project is to determine characteristics of academic neurophysiologist EEG interpreters (EEGers), which predict good interrater agreement (IRA) and to determine the number of EEGers needed to develop an ideal standardized testing and training data set for epileptiform transient (ET) detection algorithms. Methods: A three-phase scoring method was used. In phase 1, 19 EEGers marked the location of ETs in two hundred 30-second segments of EEG from 200 different patients. In phase 2, EEG events marked by at least 2 EEGers were annotated by 18 EEGers on a 5-point scale to indicate whether they were ETs. In phase 3, a third opinion was obtained from EEGers on any inconsistencies between phase 1 and phase 2 scoring. Results: The IRA for the 18 EEGers was only fair. A select group of the EEGers had good IRA and the other EEGers had low IRA. Board certification by the American Board of Clinical Neurophysiology was associated with better IRA performance but other board certifications, years of fellowship training, and years of practice were not. As the number of EEGers used for scoring is increased, the amount of change in the consensus opinion decreases steadily and is quite low as the group size approaches 10. Conclusions: The IRA among EEGers varies considerably. The EEGers must be tested before use as scorers for ET annotation research projects. The American Board of Clinical Neurophysiology certification is associated with improved performance. The optimal size for a group of experts scoring ETs in EEG is probably in the 6 to 10 range.

A retrospective cross-sectional study of the prevalence of generalized convulsive status epilepticus in traumatic brain injury: United States 2002–2010

PURPOSE To determine the incidence, predictors, and outcomes of generalized convulsive status epilepticus (GCSE) in traumatic brain injury (TBI) patients. METHODS We conducted a retrospective cross-sectional study of adult patients with acute TBI using the 2002-2010 Nationwide Inpatient Sample (NIS) database of USA. We used multivariable logistic regression analyses to identify independent predictors of GCSE in patients with TBI and to determine the impact of GCSE on outcomes (in-hospital mortality, length of stay, total hospital charges, and discharge disposition). RESULTS Among 1,457,869 patients hospitalized with TBI, 2315 (0.16%) had GCSE. In-hospital mortality was significantly higher in patients with GCSE (32.5% vs. 9.6%; unadjusted OR 4.54, 95% CI 4.16-4.96; p<0.001; adjusted OR 3.41; 95% CI 3.09-3.76 p<0.001). Patients with GCSE had longer length of stay (17.3 ± 21.9 vs. 6.8 ± 11.1 days; p<0.001), higher total hospital charges (

Pharmacoresistant epilepsy in hypomelanosis of Ito: Palliative surgical treatment with modified anatomic posterior quadrantic resection

147,415 ± 162,319 vs.

Pearls & Oy-sters: Ictal syncope in a patient with temporal lobe epilepsy

54,041 ± 90,524; p<0.001), and were less likely to be discharged home (19.8% vs. 52.7%; p<0.001). Using multivariable logistic regression analysis, age >35 years (OR 2.15; 95% CI 1.87-2.47), CNS infections (OR 4.86; 95% CI 3.70-6.38), anoxic brain injury (OR 9.54; 95% CI 8.10-11.22), and acute ischemic stroke (OR 4.09; 95% CI 3.41-4.87) were independent predictors of GCSE in TBI patients. Epilepsy was an independent negative predictor of GCSE (OR 0.74; 95% CI 0.55-0.99). CONCLUSION Despite its low incidence, GCSE in TBI patients was associated with worse outcomes with threefold higher in-hospital mortality, prolonged hospitalization, higher hospital charges, and worse discharge disposition. Surprisingly, epilepsy is a negative predictor of GCSE in this population.

Crying with sorrow evoked by electrocortical stimulation.

• The authors report modified anatomical posterior quadrant resection for adult epilepsy.