Cornelia Drees

Nonconvulsive status epilepticus

Nonconvulsive status epilepticus (NCSE) is a heterogeneous disorder with multiple subtypes. Although attempts have been made to define and classify this disorder, there is yet no universally accepted definition or classification that encompasses all subtypes or electroclinical scenarios. Developing such a classification scheme is becoming increasingly important, because NCSE is more common than previously thought, with a bimodal peak, in children and the elderly. Recent studies have also shown a high incidence of NCSE in the critically ill. Although strong epidemiological data are lacking, NCSE constitutes about 25-50% of all cases of status epilepticus. For the purposes of this review, we propose an etiological classification for NCSE including NCSE in metabolic disorders, NCSE in coma, NCSE in acute cerebral lesions, and NCSE in those with preexisting epilepsy with or without epileptic encephalopathy. NCSE is still underrecognized, yet potentially fatal if untreated. Diagnosis can be established using an electroencephalogram (EEG) in most cases, sometimes requiring continuous monitoring. However, in comatose patients, diagnosis can be difficult, and the EEG can show a variety of rhythmic or periodic patterns, some of which are of unclear significance. Although some subtypes of NCSE are easily treatable, such as absence status epilepticus, others do not respond well to treatment, and debate exists over how aggressively clinicians should treat NCSE. In particular, the appropriate treatment of NCSE in patients who are critically ill and/or comatose is not well established, and large-scale trials are needed. Overall, further work is needed to better define NCSE, to determine which EEG patterns represent NCSE, and to establish treatment paradigms for different subtypes of NCSE.

Interobserver agreement in the interpretation of EEG patterns in critically ill adults.

Summary: The significance of rhythmic and periodic EEG patterns in critically ill patients is unclear. A universal terminology is needed to facilitate study of these patterns, and consistent observer agreement should be demonstrated in its use. The authors evaluated inter- and intraobserver agreement using the standardized terminology (Hirsch et al., J Clin Neurophysiol 2005;22:128–135) recently proposed by the American Clinical Neurophysiology Society. Trained electroencephalographers viewed a series of 10-second EEG samples from critically ill adults (phase I), a set of ≥20-minute EEGs from the same patient cohort (phase II), and then reevaluated the first sample set (phase III). The readers used the proposed terminology to “score” each EEG. For each possible term, interobserver agreement (phases I and II) and intraobserver agreement (phase III) were calculated using pairwise kappa (&kgr;) values. Moderate agreement beyond chance was seen for the presence/absence of rhythmic or periodic patterns and for localization of these patterns. Agreement for other terms was slight to fair. Inter- and intraobserver agreement were consistently lower for optional terms than mandatory terms. Even when standardized terminology is used, the description of rhythmic and periodic EEG patterns varies significantly. Further refinement of the proposed terminology is required to improve inter- and intraobserver agreement.

The Histopathology of Hypothalamic Hamartomas: Study of 57 Cases

Hypothalamic hamartomas (HHs) are rare developmental tumors that cause seizures or pituitary axis dysfunction, usually beginning in childhood. We analyzed HH tissue from 57 patients whose tumors were resected through recently developed transcallosal interforniceal and transventricular endoscopic surgical approaches. All cases were composed of abnormally distributed but cytologically normal neurons and glia, including fibrillary astrocytes and oligodendrocytes. Neuronal elements predominated in most cases, but a relative increase in astrocytic elements was seen with increasing age. All had various sized nodular foci of neurons as well as areas of diffusely distributed neurons with interspersed glial cells. Smaller neurons predominated, and most cases had only a few interspersed large ganglion cells. Immunohistochemistry demonstrated extensive production of synapse-associated proteins. Immunohistochemistry for phosphorylated and nonphosphorylated neurofilament and &agr;-internexin demonstrated staining patterns consistent with mature neurons. In contrast to cortical dysplasia, atypical large ganglion-like balloon cells were almost never seen. In summary, although their number and distribution vary, mature smaller neurons were the most prominent and most consistent histologic feature of HH. Nodules of these small neurons were a universal feature of the microarchitecture of HH lesions associated with epilepsy. Characterization of these neurons may aid in understanding the mechanism of seizure development in HH.

Seizure outcome and complications following hypothalamic hamartoma treatment in adults: endoscopic, open, and Gamma Knife procedures

OBJECT This study aimed at identifying outcomes with respect to seizures, morbidity, and mortality in adult patients undergoing resective or Gamma Knife surgery (GKS) to treat intractable epilepsy associated with hypothalamic hamartoma (HH). METHODS Adult patients undergoing surgical treatment for HH-related epilepsy were prospectively monitored at a single center for complications and seizure outcome by using a proprietary database. Preintervention and postintervention data for patients 18 years of age and older, and with at least 1 year of follow-up, were analyzed, with specific attention to seizure control, complications, hormonal status, and death. RESULTS Forty adult patients were found in the database (21 were women). The median HH volume was 0.54 cm(3). In 70% of patients, it was located inside the third ventricle, attached unilaterally and vertically to the hypothalamus (Delalande Type II). Most patients (26) underwent an endoscopic resection, 10 patients had a transcallosal or other type of open (pterional or orbitozygomatic) resection, and 4 patients chose GKS. Twenty-nine percent became seizure free in the long term, and overall a majority of patients (55%) reported at least > 90% seizure improvement. Only 3 patients were ultimately able to discontinue anticonvulsants, whereas most patients were taking an average of 2 antiepileptic drugs pre- and postoperatively. The only factor significantly correlated with seizure-free outcome was the absence of mental retardation. The HH volume, HH type, and amount of resection or disconnection were not correlated to seizure freedom. A total of 4 patients (10%) died, 2 immediately after surgery and 2 later. All of them had undergone a resection, as opposed to GKS, and still had seizures. Postoperatively, persistent neurological deficits were seen in 1 patient; 34% of patients had mild hormonal problems; and 59% experienced weight gain of at least 6.8 kg (average gain 12.7 kg). CONCLUSIONS Surgical or GKS procedures in adults with HH provided seizure freedom in one-third of patients. The only significant favorable prognostic factor was the absence of mental retardation. The overall mortality rate was high, at 10%. Other important morbidities were persistent hormonal disturbances and weight gain.

Baker's Cyst Infection: Case Report and Review

Baker’s (popliteal) cysts commonly accompany noninfectious knee joint effusions. They are usually painless unless they rupture. They rarely get infected and present as an abscess in the popliteal fossa. We present such a rare case and review similar cases reported in the world literature. A Baker’s (popliteal) cyst is a distention of the gastrocnemius‐semimembranous bursa of the knee, which communicates with the posterior portion of the joint capsule. It usually appears in the popliteal fossa as a painless swelling. In adults it is nearly always secondary to pathological changes in the knee joint that cause an effusion. Occasionally the cyst becomes so large that it ruptures, spilling synovial fluid into the surrounding tissues, with a clinical presentation that mimics acute thrombophlebitis. Infection of a popliteal cyst is an uncommon complication usually associated with septic arthritis. We report such a rare case and review the world literature.

Main trunk tibial neuropathies

Abstract—The authors present a retrospective study of 52 patients with main trunk tibial neuropathy. They found trauma and ischemia to be the most frequent causes, followed by tumors. These etiologic groups are underrepresented in the literature. Electrodiagnostic examination was helpful for localizing the lesion as well as for excluding S1 radiculopathies, with which tibial neuropathies can be confused clinically.

Outcomes after hemispherectomy in adult patients with intractable epilepsy: institutional experience and systematic review of the literature

OBJECTIVE Hemispherectomy is a surgical technique that is established as a standard treatment in appropriately selected patients with drug-resistant epilepsy. It has proven to be successful in pediatric patients with unilateral hemispheric lesions but is underutilized in adults. This study retrospectively evaluated the clinical outcomes after hemispherectomy in adult patients with refractory epilepsy. METHODS This study examined 6 cases of hemispherectomy in adult patients at Barrow Neurological Institute. In addition, all case series of hemispherectomy in adult patients were identified through a literature review using MEDLINE and PubMed. Case series of patients older than 18 years were included; reports of patients without clear follow-up duration or method of validated seizure outcome quantification were excluded. Seizure outcome was based on the Engel classification. RESULTS A total of 90 cases of adult hemispherectomy were identified, including 6 newly added by Barrow Neurological Institute. Sixty-five patients underwent functional hemispherectomy; 25 patients had anatomical hemispherectomy. Length of follow-up ranged from 9 to 456 months. Seizure freedom was achieved in 80% of patients. The overall morbidity rate was low, with 9 patients (10%) having new or additional postoperative speech or language dysfunction, and 19 patients (21%) reporting some worsening of hemiparesis. No patients lost ambulatory or significant functional ability, and 2 patients had objective ambulatory improvement. Among the 41 patients who underwent additional formal neuropsychological testing postoperatively, overall stability or improvement was seen. CONCLUSIONS Hemispherectomy is a valuable surgical tool for properly selected adult patients with pre-existing hemiparesis and intractable epilepsy. In published cases, as well as in this series, the procedure has overall been well tolerated without significant morbidity, and the majority of patients have been rendered free of seizures.

Suggestion for a new, patient-oriented epilepsy classification

ZusammenfassungDer kürzlich erschienene Vorschlag der ILAE-Taskforce zur Epilepsieklassifikation ist ein multiaxialer, syndromorientierter Ansatz. Hierbei werden die Patienten unterschiedlichen und oftmals unzureichend definierten Kriterien zugeordnet. Die resultierenden Syndrome haben häufig keine ätiologische oder pathophysiologische Relevanz, überlappen und wechseln je nach Alter des Patienten. Wir schlagen einen 5-dimensionalen, patientenorientierten Ansatz zur Klassifikation der Epilepsien vor. Dieser Ansatz wendet sich von der Orientierung an Syndromen ab und basiert stattdessen auf dem methodologischen Ansatz der allgemeinen Neurologie, in dem einerseits das klinische Bild des einzelnen Patienten im Mittelpunkt steht und andererseits in jeder Dimension voneinander unabhängige und möglichst operationalisierbare Kriterien angewandt und schließlich zusammengeführt werden. Die Dimension dieser Klassifikation sind: (1) Lokalisation der epileptogenen Zone, (2) Semiologie der epileptischen Anfälle, (3) Ätiologie, (4) Anfallshäufigkeit und (5) sonstige relevante medizinische Faktoren. Diese Dimensionen enthalten alle für das Management eines Patienten notwendige Information und sind voneinander unabhängige Parameter. Alle Patienten können selbst beim initialen Patientenkontakt sinnvoll in das System eingeordnet werden, auch wenn noch keine apparativen Untersuchungen durchgeführt wurden. Die Information aller Untersuchungen (z. B. MRT, EEG) fließt zum jeweiligen Zeitpunkt der Klassifikation in die Zuordnung des Patienten ein und erlaubt mit jeder neu verfügbaren Information eine Zunahme der Präzision und Validität der Klassifikation.SummaryThe recent proposal by the ILAE Task Force for Epilepsy Classification is a multiaxial, syndrome-oriented approach. Epilepsy syndromes – at least as defined by the ILAE Task Force – group patients according to multiple, usually poorly defined parameters. As a result, these syndromes frequently show significant overlap and may change with patient age. We propose a five-dimensional and patient-oriented approach to epilepsy classification. This approach shifts away from syndrome orientation, using independent criteria in each of the five dimensions similarly to the diagnostic process in general neurology. The main dimensions of this new classification consist of (1) localizing the epileptogenic zone, (2) semiology of the seizure, (3) etiology, (4) seizure frequency, and (5) related medical conditions. These dimensions characterize all information necessary for patient management, are independent parameters, and include information more pertinent than the ILAE axes with regard to patient management. All cases can be classified according to this five-dimensional system, even at initial encounter when no detailed test results are available. Information from clinical tests such as MRI and EEG are translated into the best possible working hypothesis at the time of classification, allowing increased precision of the classification as additional information becomes available.

Reversible pontine edema in hypertension

A 28-year-old right-handed man presented with blurry vision and diplopia. He had a blood pressure of 242/182 mm Hg, papilledema, and bilateral VIth nerve palsies. Laboratory …

Clinical status epilepticus due to anaplastic cortical ependymoma.

1. IntroductionEpendymomas are glial tumors which arise from the ependy-mal lining of the cerebral ventricles and the central canal of thespinal cord.Duetomigrationfromperiventricularareastothecor-tex during the embryonal stage ependymal cells are also presentinside brain parenchyma.Ependymomas currently account for approximately 3–5% ofall intracranial malignancies in the United States, therefore mak-ing them the third most common brain tumor in children andyoung adults.Furthermore,African-Americansaremorecommonlyaffected than Caucasians.They aremorefrequentinchildren,wheretheymayaccountforabout 10% of all intrinsic brain tumors. In contrast this tumor typeis much rarer (1–2%) in adults. As a general rule, the prognosis inyoung patients seems to be worse than in adults.Anaplastic ependymomas are recognized as WHO grade III anddefined on the basis of their relative hypercellularity, cellularand nuclear pleomorphism, frequency of mitoses and endothe-lial proliferation. Only very little is known about the etiology ofependymomas, butapossibleinfectiousetiologyhasbeenhypoth-esized.This case highlights a rare clinical presentation due to anunusual localization of this type of tumor. The patient presented