Transtentorial herniation after unilateral infarction of the anterior cerebral artery.

BACKGROUND: Fatal cerebral herniation is a common complication of large ("malignant") middle cerebral artery infarcts but has not been reported in unilateral anterior cerebral artery (ACA) infarction. CASE DESCRIPTION: We report a 47-year-old woman who developed an acute left hemiparesis during an attack of migraine. Cranial CT (CCT) was normal but demonstrated narrow external cerebrospinal fluid compartments. Transcranial Doppler sonography was compatible with occlusion of the right ACA. Systemic thrombolytic therapy with tissue plasminogen activator was initiated 105 minutes after symptom onset. Follow-up CCT 24 hours after treatment revealed subtotal ACA infarction with hemorrhagic conversion. Two days later, the patient suddenly deteriorated with clinical signs of cerebral herniation, as confirmed by CCT. An extended right hemicraniectomy was immediately performed. Within 6 months, the patient regained her ability to walk but remained moderately disabled. CONCLUSIONS: This is the first reported case of unilateral ACA infarct leading to almost fatal cerebral herniation. Narrow external cerebrospinal fluid compartments in combination with early reperfusion, hemorrhagic transformation, and additional dysfunction of the blood-brain barrier promoted by tissue plasminogen activator and migraine may have contributed to this unusual course.

Placebo controlled pilot trial to study the remyelinating potential of intravenous immunoglobulins in multiple sclerosis.

Currently there is no treatment available to improve a stable deficit in multiple sclerosis. It was shown in animal models that intravenous immunoglobulins (IVIg) can enhance central nervous remyelination, and the first open trials were promising. We therefore conducted a double blind, placebo controlled pilot study to evaluate the effect of IVIg treatment in patients with multiple sclerosis with a stable clinical deficit. The primary outcome parameter was the change in central motor conduction time as an indirect measure of central myelination. Secondary outcome parameters were neurological examinations including the expanded disability status scale (EDSS), neurological rating scale (NRS), and manual muscle testing (MMT). Ten patients were treated first with placebo and then with IVIg (0.4 g/kg body weight on 5 consecutive days), the two treatments being separated by an interval of 6 weeks. There was no difference in the central motor conduction times measured before and 6 weeks after each treatment. Clinically there was a small improvement after IVIg treatment, but there was no significant difference when compared with placebo. In conclusion, our data do not support a role for IVIg in the remyelination of stable multiple sclerosis lesions as measured by central conduction time. The importance of the small clinical benefit is currently not clear.

[Headaches and facial pain]. / Kopf- und Gesichtsschmerzen.

International headache classification systems presently differentiate between more than 150 types of headaches and facial pain. This paper subdivides the most frequent types of pain according to the duration of typical manifestations. It deals with the most commonly occurring syndromes as well as those indicative of life-threatening conditions. In most of these clinical pictures, the diagnosis has to be established on the basis of a carefully evaluated case history. Indications for additional technical examinations are critically assessed.

Callosal disconnection syndrome in a left-handed patient due to infarction of the total length of the corpus callosum.

We report on a left-handed patient with an ischemic infarction affecting exclusively the total length of the corpus callosum. This lesion clinically correlated with an almost complete callosal disconnection syndrome as described in callosotomy subjects, including unilateral verbal anosmia, hemialexia, unilateral ideomotor apraxia, unilateral agraphia, unilateral tactile anomia, unilateral constructional apraxia, lack of somesthetic transfer and dissociative phenomena. Despite the patient's left-handedness, his pattern of deficits was similar to the disconnection syndrome found in right-handers. Our report focusses on motor dominance and praxis. We followed-up the improvement in left apraxia and investigated the ability to initiate and learn a new visuo-motor skill. The results permit two tentative assumptions: (1) that the improvement in left apraxia was due to a compensatory increase in ipsilateral proximal muscle control, and (2) that motor dominance, i.e. the competence to initiate and learn a new movement pattern, was hemispherically dissociable from manual dominance in the sense of praxis control.

[Septo-optic dysplasia (de Morsier syndrome)]. / Septooptische Dysplasie (de-Morsier-Syndrom).

Septo-optic dysplasia (or de Morsier syndrome) is a congenital disorder characterised by anomalies in cerebral midline structures, optic nerve hypoplasia, and hormonal deficiencies. Diagnosis should be made early, due to the possibility of treating the hormonal disturbances. We describe here a case with decreased visual acuity, one-sided hemianopia, nystagmus und agenesis of the septum pellucidum and discuss the heterogeneous appearance of this syndrome. There are two theories regarding its pathogenesis. The first postulates simultaneous damage to both cerebral structures and optic nerve development around the 6th week of gestation, while the other favours secondary degeneration of optic nerve fibres due to a cerebral lesion.

Immunoglobulins for intravenous use inhibit TNF alpha cytotoxicity in vitro.

Intravenous immunoglobulins (IVIg) have been used as an immunomodulatory therapy in a variety of diseases. Several mechanisms of action have been proposed, one of which is interference with the cytokine network. We have investigated the effect of IVIg on the cytotoxicity of human TNF alpha. IVIg was capable of protecting L929 fibroblasts from TNF alpha induced cell death. This effect was not species specific and was mediated by both the Fc and the Fab portion of immunoglobulins. Since the effect was also seen when IVIg was added after the removal of TNF alpha from the culture medium, it seems to be independent of the interaction of TNF alpha with its receptor. We conclude that IVIg either act on some point of the TNF alpha signalling pathway or influence the cell cycle unspecifically. The cytoprotective effect of IVIg potentially could contribute to the beneficial effect described for various diseases.

[A quickly reversible occlusion in the vertebrobasilar circulatory bed: often unrecognized?]. / Schnell reversibler Verschluss im vertebrobasilären Stromgebiet: oft unerkannt?

HISTORY AND FINDINGS: A 29-year-old man presented in another hospital because of discoordination of all extremities with sudden onset. After fast reversal of the symptoms, he was discharged without a clear diagnosis. Because of remaining discrete dysarthria, computed tomography and magnetic resonance imaging were performed which demonstrated bilateral cerebellar infarcts. The cause was assumed to be a transient embolic occlusion of the distal basilar artery. TREATMENT AND COURSE: Intravenous heparin was started to prevent further occlusions. Because no source for emboli or other causes were found, the patient was discharged after 14 days on acetylic acid (250 mg/d) as secondary prevention therapy. CONCLUSIONS: A vascular or neurological cause is often not considered when neurological symptoms are quickly reversible after a transient occlusion of the basilar artery. In these cases, the suspected diagnoses of psychiatric illness, alcohol abuse, drug intoxication, infection or myocardial infarction do not lead to the necessary investigations. Thus, a potentially life-threatening situation may be disregarded.

Neurological syndromes in factitious disorder.

Factitious disorder is characterized by the intentional feigning of physical or psychological signs and symptoms. The best known type of factitious disorder, Munchausen syndrome, is marked by a chronic unremitting course with repeated hospitalizations. The purpose of this study was to assess the frequency, psychopathological phenomenology, and diagnostic classification according to DSM-III-R in patients with factitious disorder presenting as neurological syndromes. We prospectively included all patients who were hospitalized at our Department of Neurology, Freie Universität Berlin, during a 1-year period. Five of 1538 (.3%) patients were diagnosed as having factitious disorder with feigning of neurological syndromes. Four presented with the classic variant, Munchausen syndrome. All patients had similar, characteristic psychopathological features including self-discharge, aggressive behavior, pseudologia phantastica, and hospital wandering. In these cases the additional diagnosis of personality disorder was made according to DSM-III-R criteria. We concluded that factitious disorder presenting with neurological syndromes may be more prevalent than generally assumed. Our findings confirm the idea of frequent coincidence of factitious and personality disorders.

The value of magnetic resonance imaging in carpal tunnel syndrome.

We examined 62 patients (72 hands) with carpal tunnel syndrome (CTS) by magnetic resonance imaging (MRI) of the carpal tunnel and latency measurements of the median nerve. In 32 of 72 hands a probable causative lesion of the CTS was identified by MRI, for example tenosynovitis, a cyst-like structure, or an aberrant muscle. The MRI findings were confirmed by surgery in 16 of 24 hands, slightly corrected in 5, and not substantiated in 3. In 65 of 72 hands, MRI disclosed pathology of the median nerve, most prominently an enlargement of the nerve at the level of the os pisiforme, a finding not seen during surgery. Oedema of the nerve was found in 14 of 72 hands. The distal latencies were prolonged in 62 of 72 hands. The sensory latencies correlated significantly with the MRI-determined cross-sectional area of the nerve at the level of the distal radius. The lack of other correlations suggests that partly independent features of the nerve lesion are demonstrated in each method or that the sensitivity and specificity of both methods are limited. Further experience with MRI in CTS is desirable. At present, the practical use of MRI in CTS should be restricted to special diagnostic problems such as carpal tunnel syndromes which do not respond adequately to conservative or surgical treatment.

PCBs have a predominantly neurotoxic effect on dissociated cultures of the nervous system.

Although their manufacture and use have been restricted or banned in Europe and the United States since the 1970s, polychlorinated biphenyls (PCBs) are still an ubiquitous environmental contaminant whose low-term effects are as yet not completely clear. Clinical case studies of patients with occupational exposure report cognitive impairment and peripheral neuropathy. In our defined nerve cell culture models in which we use pure neurons, pure glia and mixed cultures prepared from dorsal root ganglia of chick embryos we observed a neurotoxic effect after the application of a PCB compound (Clophen). It was only at higher concentrations that an additional gliatoxic effect could be observed.

Glia toxicity in dissociation cell cultures induced by cyclosporine.

Intravenously applied cyclosporine is the most effective and best analyzed immunosuppressive agent to date. Most frequently, this drug shows nephrotoxic or hepatotoxic side effects, which have already been investigated in detail. In addition to these adverse effects, there is also clear clinical evidence for toxic damage to the central nervous system. On the basis of magnetic resonance tomography and computed tomography studies, the white matter seems to be primarily affected. A systematic approach to neurotoxicity has been established in the following model. Mixed in-vitro cell cultures of dorsal root ganglia (DRG) and of the central nervous system were prepared from 6 to 14 day old chick embryos (E6-E14). For cultivation of nerve and glia cells we used beta NGF, a soluble trophic factor, and NTF B 82 as a matrix factor. Differentiated cultures were incubated with cyclosporine for intravenous application. Within a period of several days up to two weeks the cultures were analyzed using phase contrast microscopy, light microscopy, scanning and transmission electron microscopy. Glia cells and fibroblasts showed the most pronounced toxic effects. Their cytoplasm was infiltrated with smaller and larger vesicles which contained neutral lipids. Control cultures remained unaffected. Because of the close correlation between the in-vitro damage of glia cells and the clinically observed alteration of the white matter, we think our in-vitro model is helpful for the investigation of the neurotoxic effects of cyclosporine and immunotherapeutic drugs.

2,5-Hexanedione is a potent gliatoxin in in-vitro cell cultures of the nervous system.

Of the metabolites of hexane, 2,5-hexanedione (2,5 HD) has the strongest neurotoxic effect. There is a wealth of experimental studies in animals showing an axonotoxic mechanism consisting of an accumulation of 10 nm neurofilaments. Only few studies deal with a possible action of 2,5-HD on Schwann cells, glia cells or both. Pure neurons, pure glia and mixed cultures prepared from dorsal root ganglia (DRG) of chick embryos were studied in this model. DRG were chosen because they constitute a linkage between the peripheral and central nervous system and provide the additional advantage of containing only few defined glial and neuronal cell types. Additionally, pure neuronal cultures of sympathetic ganglia and mixed cultures of spinal cord and brain were prepared. In cultures of the different parts of the nervous system investigated, we observed at a concentration of 0.25% 2,5-HD massive toxic alterations of glial cells, whereas neurons and neurites were virtually unaffected.

Specific neurotoxic effects of different organic solvents on dissociated cultures of the nervous system.

Pure neurons were prepared from dorsal root ganglia (DRG) of 8 day old chick embryos (E8). The substances tested in this model were pure n-hexane, 2.5-hexanedione (2.5 HD) and methyl-ethyl-ketone (MEK). Differentiated cultures were exposed to these neurotoxins after two days in culture and then examined over a period of up to one week. For all three substances a specific neurotoxic effect could be demonstrated: (i) n-Hexane mainly altered the neurites, leading to focal swellings and in a second step to degenerative changes in glial cells; (ii) 2.5 HD had a minor effect on neurons and proved to be mainly gliatoxic; (iii) MEK primarily affected the neurons by swelling and disintegration of the cell body.