Paul B. Pritchard

Psychological complications of temporal lobe epilepsy

A series of young adults with temporal lobe epilepsy included 36% with psychological complications. The incidence of overt psychosis was 11%. Psychopathology was more common in subjects with left temporal lobe spike foci (43%) and in males (4%), but these trends did not attain statistical significance. Psychological complications became manifest in adolescence in 85% of the affected cases, and were more likely (p < 0.01) to occur when seizures began in the second 5 years of life. Although seizures nearly always antedated psychological problems, the onsets of epilepsy and psychological complications did not directly correlate (p = 0.43).

Standardized database development for EEG epileptiform transient detection: EEGnet scoring system and machine learning analysis

The routine scalp electroencephalogram (rsEEG) is the most common clinical neurophysiology procedure. The most important role of rsEEG is to detect evidence of epilepsy, in the form of epileptiform transients (ETs), also known as spike or sharp wave discharges. Due to the wide variety of morphologies of ETs and their similarity to artifacts and waves that are part of the normal background activity, the task of ET detection is difficult and mistakes are frequently made. The development of reliable computerized detection of ETs in the EEG could assist physicians in interpreting rsEEGs. We report progress in developing a standardized database for testing and training ET detection algorithms. We describe a new version of our EEGnet software system for collecting expert opinion on EEG datasets, a completely web-browser based system. We report results of EEG scoring from a group of 11 board-certified academic clinical neurophysiologists who annotated 30-s excepts from rsEEG recordings from 100 different patients. The scorers had moderate inter-scorer reliability and low to moderate intra-scorer reliability. In order to measure the optimal size of this standardized rsEEG database, we used machine learning models to classify paroxysmal EEG activity in our database into ET and non-ET classes. Based on our results, it appears that our database will need to be larger than its current size. Also, our non-parametric classifier, an artificial neural network, performed better than our parametric Bayesian classifier. Of our feature sets, the wavelet feature set proved most useful for classification.

Prevalence of neoplasms and causes of death in paralysis agitans A necropsy study

Doshay contended i n 1954 that cancer is seldom associated with paralysis agitans. “For reasons as yet unclear, cancer is phenomenally rare in paralysis agitans, despite the fact that the patients are in the age group of 45 t o 75, when the expectancy of cancer in the general population is high.”’ Specific data t o support this statement were not given, but the author was able t o recall only a single instance of a malignant neoplasm among the many parkinsonian patients he had treated. Two years later, Westlund and Hougen’ responded with data drawn from a study of death certificates in Oslo, with occasional necropsy confirmation. They refuted Doshay’s opinion by finding that deaths from cancer in parkinsonian patients occurred twice as often as the predicted incidence. Interest in “cancer-producing milieu” led t o another , determination of the frequency of cancer in patients with parkinsonism. Barbeau and J01y3 in Montreal studied malignant neoplasms in patients examined during a 12 year

Transient Kluver–Bucy syndrome following complex partial status epilepticus

The characteristic features of Kluver-Bucy syndrome include hypersexuality, hyperorality, placidity, hypermetamorphosis, visual agnosia, changes in dietary habits, and memory impairment. Human cases have been reported with herpes simplex encephalitis, head injury, Picks disease, transtentorial herniation, adrenoleukodystrophy, and Reyes syndrome, all involving bilateral temporal lobe pathology. We present the case of a patient with no evidence of a structural lesion in the temporal lobes and behavioral changes consistent with Kluver-Bucy syndrome following complex partial status epilepticus.

Web-based collection of expert opinion on routine scalp EEG: software development and interrater reliability.

Computerized detection of epileptiform transients (ETs), characterized by interictal spikes and sharp waves in the EEG, has been a research goal for the last 40 years. A reliable method for detecting ETs would assist physicians in interpretation and improve efficiency in reviewing long-term EEG recordings. Computer algorithms developed thus far for detecting ETs are not as reliable as human experts, primarily due to the large number of false-positive detections. Comparing the performance of different algorithms is difficult because each study uses individual EEG test datasets. In this article, we present EEGnet, a distributed web-based platform for the acquisition and analysis of large-scale training datasets for comparison of different EEG ET detection algorithms. This software allows EEG scorers to log in through the web, mark EEG segments of interest, and categorize segments of interest using a conventional clinical EEG user interface. This software platform was used by seven board-certified academic epileptologists to score 40 short 30-second EEG segments from 40 patients, half containing ETs and half containing artifacts and normal variants. The software performance was adequate. Interrater reliability for marking the location of paroxysmal activity was low. Interrater reliability of marking artifacts and ETs was high and moderate, respectively.

Transient epileptic amnesia: A neurosurgical case report

One memory disorder that is potentially treatable with antiepileptic drugs is transient epileptic amnesia (TEA). Working diagnostic consensus criteria for TEA include: (1) a history of recurrent witnessed episodes of transient amnesia; (2) confirmation by a reliable witness that cognitive functions other than memory are intact during typical episodes; and (3) evidence for a diagnosis of epilepsy. We describe a case with both complex partial seizures and episodes of TEA. This is the first reported case of a neurosurgical intervention for symptoms resembling those described in refractory TEA. Video/EEG, 3-T MRI, neuropathology, and neurological as well as neuropsychological findings are presented with postsurgical clinical outcome. The patient underwent right anterior amygdalohippocampectomy for symptoms resembling refractory TEA with additional complex partial seizures at our epilepsy surgical center. She remained seizure free at the 15-month follow-up, and memory complaints remitted. This case report illustrates one memory disorder, transient epileptic amnesia, that is potentially treatable with antiepileptic drugs or surgery.

Unique Case of “Post-Lumbar Puncture Headache”

Lumbar puncture (LP) is associated with complications that include post‐LP orthostatic headache, local bleeding, and subdural hematoma. We report a unique case of a spontaneous frontal epidural hematoma following a therapeutic lumbar puncture in a patient with a history of idiopathic intracranial hypertension. This case highlights the importance of symptomatology in patients following LPs by revealing a rare intracranial presentation that would be devastating if not discovered promptly and appropriately managed.

Effect of lunar phase on frequency of psychogenic nonepileptic events in the EMU

INTRODUCTION Studies of the effect of a full moon on seizures have yielded mixed results, despite a continuing prevailing belief regarding the association of lunar phase with human behavior. The potential effect of a full moon on psychogenic nonepileptic events has not been as well studied, despite what anecdotal accounts from most epilepsy monitoring unit (EMU) staff would suggest. METHODS We obtained the dates and times of all events from patients diagnosed with psychogenic nonepileptic events discharged from our EMU over a two-year period. The events were then plotted on a 29.5-day lunar calendar. Events were also broken down into lunar quarters for statistical analysis. RESULTS We found a statistically significant increase in psychogenic nonepileptic events during the new moon quarter in our EMU during our studied timeframe. CONCLUSION Our results are not concordant with the results of a similarly designed past study, raising the possibility that psychogenic nonepileptic events are not influenced by lunar phase.

Prevalence and distribution of MRI abnormalities in patients with psychogenic nonepileptic events

INTRODUCTION Both structural and functional abnormalities have been reported in patients with psychogenic nonepileptic events (PNEEs), although no truly consistent abnormalities have been found. METHODS We retrospectively identified patients discharged from our EMU with video-EEG diagnoses of epileptic seizures, PNEEs, epileptic seizures plus PNEEs, interictal epileptiform abnormalities only, and nondiagnostic admissions. We then collected brain MRI results for analysis. RESULTS We found significant brain MRI abnormalities in 33.8% of patients with PNEEs, clearly higher than the rate of brain MRI abnormalities in the healthy population. In addition, we found statistically significant differences in the locations of brain MRI abnormalities in patients with epileptic seizures (more frequently temporal) versus PNEEs (more frequently multifocal). CONCLUSION This multifocal nature of abnormalities in patients with psychogenic nonepileptic events may help to explain the underlying pathophysiology as it relates to psychiatric disorders which are so frequently comorbid with PNEEs.