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Non-convulsive status epilepticus (NCSE) is characterized by continuous or recurrent, generalized or focal epileptiform activity on the electroencephalogram and diverse clinical symptoms with alterations of mental state and vigilance. NCSE is not rare but certainly under diagnosed. There is some debate about how aggressive NCSE should be treated, as high dose anticonvulsants maybe partially responsible for the morbidity and mortality of patients with NCSE. We hypothesized that levetiracetam (LEV) as a well tolerated, highly effective new anticonvulsant, may be a safe treatment option. We retrospectively analyzed all (8) patients with NCSE who received levetiracetam from our database, compared with 11 patients with NCSE treated with conventional intravenous status medication as controls. These eight patients showed a marked clinical improvement with final cessation of ictal EEG-activity and clinical symptoms of NCSE after initiation of LEV within 3 days (mean 1.5 days). The response to conventional treatment was similarly effective but there were severe side effects whereas no relevant side effects in the LEV-treated group were noticed. A long-term follow up (6-36 months from discharge) revealed six patients with a persisting reduction in seizure frequency on medication with LEV. One patient changed the anticonvulsive medication because of inefficacy and one died from other causes than epilepsy 2 months after discharge from hospital. We found no significant differences in hospitalisation time, time in intensive care unit and outcome between the LEV group and the control group. This retrospectively acquired data suggests that LEV may be a well tolerated, effective treatment option in NCSE. This highlights the need for a prospective controlled study to further elucidate the utility of LEV in the treatment of NCSE, particularly as an intravenous formulation is now available.

Purpose To study the time course of diffusion imaging at the lesion site in brainstem infarcts. Materials and Methods Sequential MR scans were acquired from 24 patients with brainstem infarcts. Diffusion-weighted images (DWI), T2-weighted images (T2w), maps of apparent diffusion coefficient, and maps of fractional anisotropy were generated from each MR scan. A trend function was fitted to these measurements to model an objective, general time course of the studied parameters. Results Apparent diffusion coefficient (ADC) continuously decreased over time until a transition time around 45 hours; afterwards a continuous increase took place. After the 14th day ADC reached values similar to the ADC of the intact contralateral side (pseudonormalization) and then further increased. Fractional anisotropy (FA) decreased continuously over 3 to 6 months. Conclusion Times of transition and pseudonormalization of ADC were longer than described for territorial hemispheric infarcts and describe the acute to subacute phase of brainstem ischemia. In contrast, the continuous decline of FA over 3 to 6 months indicates a chronic process of change of histological structures in brainstem ischemia, and may be regarded as an indicator of the chronic phase. J. Magn. Reson. Imaging 2007;26:905–912. © 2007 Wiley-Liss, Inc.

Introduction There are reports of an ischemic stroke during intravenous recombinant tissue-type plasminogen activator (rtPA) for evolving myocardial infarction (MI), and the risk of stroke shortly after an acute MI seems to be higher than in the control population, attributed to intracardiac thrombus formation. Case report We report a case of fatal MI developing immediately after the start of rtPA infusion for middle cerebral artery stroke in an 88-year-old woman. We assume that the systemic thrombolysis with rtPA led to the fragmentation of an underlying cardiac thrombus, which embolized and occluded the coronary artery and caused MI. This hypothesis is discussed with respect to a short review of the related literature. Conclusions An embolic MI seems to be a rare but serious complication in thrombolysis therapy with rtPA.

Summary: Purpose: Valproic acid (VPA) is an antiepileptic drug (AED) commonly used for generalized and focal epilepsies. We provide an update on hepatotoxic side effects in Germany between 1994 and 2003. Methods: We mailed a questionnaire to all members of the German Section of the International League Against Epilepsy, asking for VPA-induced side effects, especially severe side effects such as hepatopathy. Results: As a result of our questionnaire, we found 31 cases of reversible hepatotoxicity and nine cases of lethal hepatopathies in Germany from 1994 to 2003. Conclusions: The outcome of patients with severe hepatotoxicity is better than that in the past. The risk of a VPA-induced hepatopathy is not limited to patients younger than 2 years, receiving polytherapy, or patients with congenital or acquired metabolic diseases.

Isolierte Hirnstamminfarkte stellen klinisch und in der Bildgebung eine gesondert zu betrachtende Gruppe von Infarkten dar. In Ermangelung geeigneter atiologischer und bildmorphologischer Kategorien werden Hirnstamminfarkte zumeist als nosologische Entitat betrachtet, was Aussagen zur Atiologie und zur Prognose problematisch macht. Die getrennte Untersuchung klar definierter Subgruppen erscheint daher sinnvoll. Im Kurz- und Langzeitverlauf haben solitare Hirnstamminfarkte eine gute Prognose mit geringer Mortalitat, guter Funktionserholung und geringer Rezidivrate. Am Hirnstamm fehlen bislang sichere morphologische Kriterien zur Unterscheidung verschiedener Infarktursachen. Es finden sich jedoch typische Gefasterritorien, die haufig von Infarkten betroffen sind, wenngleich typische embolische Verteilungsmuster sich nicht darstellen lassen. Diffusionsgewichtete Sequenzen (DWI) sind auch am Hirnstamm hochsensitiv im Nachweis frischer Infarkte. Im Hinblick auf die kleinen und dichtgepackten funktionstragenden Strukturen des Hirnstamms ist es von klinischem Interesse, dass selbst grosere DWI-Veranderungen nicht automatisch zu einem schweren neurologischen Defizit fuhren mussen.

Our current understanding of brainstem reflex physiology comes chiefly from the classic anatomical-functional correlation studies that traced the central circuits underlying brainstem reflexes and establishing reflex abnormalities as markers for specific areas of lesion. These studies nevertheless had the disadvantage of deriving from post-mortem findings in only a few patients. We developed a voxel-based model of the human brainstem designed to import and normalize MRIs, select groups of patients with or without a given dysfunction, compare their MRIs statistically, and construct three-plane maps showing the statistical probability of lesion. Using this method, we studied 180 patients with focal brainstem infarction. All subjects underwent a dedicated MRI study of the brainstem and the whole series of brainstem tests currently used in clinical neurophysiology: early (R1) and late (R2) blink reflex, early (SP1) and late (SP2) masseter inhibitory reflex, and the jaw jerk to chin tapping. Significance levels were highest for R1, SP1 and R2 afferent abnormalities. Patients with abnormalities in all three reflexes had lesions involving the primary sensory neurons in the ventral pons, before the afferents directed to the respective reflex circuits diverge. Patients with an isolated abnormality of R1 and SP1 responses had lesions that involved the ipsilateral dorsal pons, near the fourth ventricle floor, and lay close to each other. The area with the highest probabilities of lesion for the R2-afferent abnormality was in the ipsilateral dorsal-lateral medulla at the inferior olive level. SP2 abnormalities reached a low level of significance, in the same region as R2. Only few patients had a crossed-type abnormality of SP1, SP2 or R2; that of SP1 reached significance in the median pontine tegmentum rostral to the main trigeminal nucleus. Although abnormal in 38 patients, the jaw jerk appeared to have no cluster location. Because our voxel-based model quantitatively compares lesions in patients with or without a given reflex abnormality, it minimizes the risk that the significant areas depict vascular territories rather than common spots within the territory housing the reflex circuit. By analysing statistical data for a large cohort of patients, it also identifies the most frequent lesion location for each response. The finding of multireflex abnormalities reflects damage of the primary afferent neurons; hence it provides no evidence of an intra-axial lesion. The jaw jerk, perhaps the brainstem reflex most widely used in clinical neurophysiology, had no apparent topodiagnostic value, probably because it depends strongly on peripheral variables, including dental occlusion.

The aim of this study was to evaluate the applicability, sensitivity, and predictive power of diffusion-weighted MR imaging (DWI) in the diagnosis of vertebrobasilar infarction. From 1997 to 2002, we prospectively recruited 268 patients with acute signs and symptoms suspective of vertebrobasilar ischemia. The patients underwent biplanar EPI-T2 and EPI DWI within 24 h after onset of symptoms and high-resolution MRI as a control within 7 days. One hundred twenty-one patients had additional CT scanning. The DWI revealed acute vertebrobasilar infarction in 71.0%. The mean time exposure of DWI was 8 min and thus no more than that of CT imaging. It showed significantly more acute lesions than CT imaging (28.0%), but additional high-resolution MRI was not able to reveal more lesions than DWI alone. Even in 42 patients with reversible brainstem or cerebellar symptoms classified as TIA or PRIND, DWI demonstrated acute ischemia in 42.8%. Sixty-three patients with optimal final diagnosis of vertebrobasilar ischemia had normal DWI. One week after onset of symptoms, 88.9% of these patients had recovered completely or showed minimal symptoms. Therefore, DWI is a sensitive indicator of acute vertebrobasilar ischemia. It is no more time-consuming than CT imaging, and normal DWI is a predictor of good clinical outcome in patients with brainstem or cerebellar infarction.

Three patients with acute large paramedian ponto-mesencephalic infarctions developed a bilateral retrograde degeneration of the medial cerebellar peduncles within 4 months after the insult. In an initial magnetic resonance imaging (MRI) within the first 2 weeks, the medial cerebellar peduncles showed normal intensities, but a control MRI after 4 months showed bright hyperintensities in the T2-TSE weighted images, and moderately increased signal intensities in echo planar imaging-diffusion weighted imaging were seen, possibly representing bilateral Wallerian degeneration of the cerebellar-pontine fibers.

Several functional brain imaging studies of pain using positron emission tomography (PET) and functional magnetic resonance imaging (fMRI) have shown that painful stimulation causes activation of different brain areas. The aim of the present study was to develop and implement painful stimulation of the trigeminal nerve, which can be applied with event-related paradigms by using MRI. Twelve healthy, right-handed volunteers were examined. Painful electrical stimulation of the first trigeminal branch was performed. In an event-related setting with a 1.5 T clinical scanner with EPI capability, the following fMRI parameters were used: 20 slices, 3 mm thickness, isotropic voxel, 306 measurements with 54 randomized events. Statistical postprocessing was performed with SPM99. Activation of the ipsi- and contralateral secondary somatosensory cortex (SII), and the contralateral insular cortex was observed as well as a contralateral thalamic activation (T = 4.45, extension 15 voxels). Six of the 12 volunteers revealed also activation of the cingulate cortex. The investigation demonstrates that painful stimulation of the trigeminal nerve activates the contralateral insular cortex, SII, and thalamus, as well as the ipsilateral SII. In contrast to other studies, the cingulate cortex was only activated inconsistently.

Seit langer Zeit sind typische Hirnstammsyndrome bekannt. Eines der haufigsten ist das Wallenberg- Syndrom bei dorsolateralem Medulla-oblongata-Infarkt. Ursache ist hier meist ein Verschluss der ipsilateralen PICA. Die Vielzahl der Syndrome auf der einen Seite sowie die Klassifikation der Hirnstamminfarkte in Gruppen andererseits konnen als Hinweis darauf angesehen werden, dass die Hirnstamminfarkte regelmasig bestimmte Territorien und Gebiete bevorzugen. Inwieweit diese Hypothese zutrifft, sollte an einem Patientenklientel mit akuten Hirnstamminfarkten untersucht werden. Ziel unserer Arbeit war die Darstellung typischer Lasionsverteilungen bei Patienten mit akutem Hirnstamminfarkt. Bei 117 Patienten mit akutem, klinisch und im MRT nachgewiesenem Hirnstamminfarkt wurden die MRT-Lasionen (T2-w) normalisiert und schichtweise ubereinander projiziert. Zur besseren Vergleichbarkeit wurden alle Lasionen auf dieselbe Seite projiziert. Die Lasionen wurden sowohl anatomisch mit Hilfe anatomischer Atlanten korreliert als auch zu bekannten Darstellungen der Hirnstammdurchblutung in Verbindung gesetzt. Die 117 Patienten (36 Frauen, 81 Manner) waren im Mittel 63,5 Jahre alt (Median 64,5; SD 12,7 Jahre). 85 Patienten (73%) hatten solitare frische Hirnstamminfarkte, 19 Patienten (16%) wiesen zusatzlich frische Kleinhirninfarkte auf, neun Patienten (8%) zusatzlich frische supratentorielle Infarkte. Vier Patienten (3,4%) hatten multiple frische Infarkte in mindestens drei Gefasterritorien. 65 Patienten (56%) wiesen im MRT keine Hinweise auf vorangegangene Ischamien auf. Die Hirnstamminfarkte zeigten typische Verteilungsmuster in unterschiedlichen Hohen in Bezug auf Ausdehnung, Schwerpunkt und im Verhaltnis zur Mittellinie, den auseren Begrenzungen des Hirnstammes und den bekannten Gefasterritorien. In unserer Studie lag das Maximum nach Uberlagerung aller Infarkte in Hohe der Medulla oblongata im lateralen Gefasterritorium, welches von den Vertebralarterien uber die PICA versorgt wird. In Ubereinstimmung mit der klinischen Erfahrung, dass paramediane Ponsinfarkte die “typischen“ Ponsinfarkte darstellen, fanden wir das Maximum aller pontinen Infarkte weiter ventral in den anteromedialen und anterolateralen Gefasterritorien, hervorgerufen durch Gefasverschlusse pontiner Aste aus der Arteria basilaris. Mesenzephal schlieslich lag das Maximum aller Infarkte erneut im anteromedialen und anterolateralen Gefasterritorium. Diese Untersuchung kann als Basis dienen, uber die Analyse der Lasionsverteilung „typisch“ lokalisierte Hirnstamminfarkte von atypischen Lasionen zu differenzieren. Dies konnte insbesondere bei einzelnen, differentialdiagnostisch fraglichen Lasionen hilfreich sein.

Im Rahmen dieser Studie sollte untersucht werden, ob sich eine diffusionsgewichtete Sequenz eignet, unter Ausnutzung der anisotropen Diffusionsverhaltnisse entlang der Markfasern die Zentralregion (ZR) bei Probanden und Patienten verlasslich darzustellen. Funf Patienten mit Hirntumoren und 20 gesunde Probanden wurden an einem klinischen 1,5-TMR-Tomographen untersucht. Bei den Probanden dienten die „klassischen“ anatomischen Zeichen zur Lokalisation der Zentralregion an einem 3-D-T1-Datensatz als Goldstandard zur Lokalisation, bei den Patienten zusatzlich noch ein funktionelles Magnet-resonanztomogramm (fMRT) mit einem Finger-Tapping-Paradigma im Blockdesign und der intraoperative Befund. Bei den Probanden konnte die Zentralregion in allen Fallen durch ihre Faserverlaufsrichtung und dadurch selektiv in anterior-posteriorer Richtung behinderte Diffusion lokalisiert werden. Hierzu waren keine weiteren Nachverarbeitungsprozesse notwendig. Bei den Patienten bestand eine gute Korrelation zwischen Diffusionswichtung-(DWI-)Befund, den fMRT-Ergebnissen und der intraoperativen Lokalisation. Mit EPI-DWI kann man bei Probanden und Patienten reproduzierbar, einfach und mit hoher Zuverlassigkeit die ZR darstellen.

Purpose To investigate if primary cholesteatomas of the petrous bone show high signal in diffusion-weighted imaging (DWI). Materials and methods In this blinded study, we compared 15 patients with clinically certain cases and later surgically proven cholesteatomas vs. 12 patients with clinically acute otitis of the middle ear and 20 volunteers without petrous bone disease. Two blinded readers without knowledge of the clinical data decided in consensus agreement whether there was a pathologic signal increase in the petrous bone in an anisotropic single-shot echo-planar imaging (EPI) DWI sequence, an artifact, or no signal increase. Results Thirteen of 15 patients with cholesteatomas showed bright signal in EPI DWI, whereas 10 of 12 patients with acute otitis media and all volunteers presented the usual low signal of petrous bone. Conclusion EPI DWI is a fast diagnostic method that may be an additional valuable tool in the workup of suspected cholesteatomas. The ability of this technique to differentiate between cholesteatomas and granulomas or chronic otitis is not yet available.

We investigated the reliability of a new digital post-processing magnetic resonance imaging (MRI) technique in ischemic brain stem lesions to identify relations of the lesion to anatomical brain stem structures. The target was a medial longitudinal fasciculus (MLF) lesion, which was evident from ipsilateral internuclear ophthalmoplegia (INO). Sixteen patients with acute unilateral INO and an isolated acute brain stem lesion in T2- and EPI-diffusion weighted MRI within 2 days after the onset of symptoms were studied. The MRI slice direction was parallel and perpendicular to a slice selection of a stereotactic anatomical atlas. The individual slices were normalized and projected in the digitalized atlas. The eye movement disorder was monitored by electro-oculography. In all patients with clinical or subclinical electro-oculographically documented INO and MRI proven brain stem infarction the lesion covered or at least partially overlapped the ipsilateral MLF at one or more atlas levels. We conclude that digital post-processing MRI with normalizing and projecting brain stem lesions in an anatomical atlas is a reliable method to demonstrate the anatomical structures involved by the lesion. Combined with electrophysiological brain stem testing, this method may be a useful tool to identify incompletely understood pathways mediating brain stem reflexes or the generators of evoked potentials.

The purpose of this study was to identify clinical predictors and anatomical structures involved in patients with pain after dorsolateral medullary infarction. Eight out of 12 patients (67%) developed poststroke pain within 12 days to 24 months after infarction. The pain occurred in the ipsilateral face (6 patients) and/or the contralateral limbs and trunk (5 patients, 3 of whom also had facial pain). Ipsilateral facial pain was significantly correlated with lower medullary lesions, including those of the spinal trigeminal tract and/or nucleus, as documented by magnetic resonance imaging. The R2 blink reflex component was abnormal only in patients with facial pain. Likewise, pain and temperature sensation in the ipsilateral face was decreased in all patients with facial pain but not in patients without pain. Ipsilateral touch sensation in the face was also decreased in all patients with facial pain, but the lesions revealed on magnetic resonance imaging did not involve the principal sensory nucleus of the fifth cranial nerve, and the R1 blink reflex latencies were normal. Although facial pain was correlated with lesions of the spinal trigeminal tract and/or nucleus, none of the lesions involved the subnucleus caudalis, which contains most nociceptive neurons. These findings suggest that facial pain after medullary infarction is due to lesions of the lower spinal trigeminal tract (axons of primary afferent neurons), leading to deafferentation of spinal trigeminal nucleus neurons.

Objectives: Normative values of the masseter reflex are scarce. We studied the latencies, amplitudes and side differences of the masseter reflex in 105 healthy volunteers between the ages of 5 and 78 years. Methods: Latencies were calculated as the mean of 10 single sweeps and, simultaneously, measured from the summation curve. Short-term reproducibility was determined in 33 volunteers by retesting the reflex after 1 week. Results: There was a positive correlation between age and latencies and a negative correlation between age and amplitude. Maximal normal latencies were 8.3 ms for men and 7.9 ms for women in the age group below 50 years and 9.1 and 9.2 ms for the age group above 50 years. Latency differences between the right and left sides of >0.4 ms for subjects aged below 50 years and >0.5 ms for subjects aged above 50 years exceeded the 95% confidence interval. Amplitudes did not depend on gender. Calculated as a percentage of the side with higher amplitude, differences above one third could be accepted as abnormal. Conclusion: The masseter reflex appears to be a stable and robust clinical test, if age and gender differences are taken into account.

We performed MRI, including diffusion-weighted imaging, in 15 patients with recurrent strokes with acute ischaemia and at least one old lesion according to the clinical history and/or CT. Routine MRI showed similar signal intensity changes in both situations. Diffusion-weighted images, however, were positive in all acute or subacute infarcts. The high signal of acutely disturbed diffusion due to intracellular oedema could also be identified in small brain stem lesions. Spatial resolution was increased by applying separate gradients in each axis instead of creating anisotropy-independent trace images.

Background: The intention of this study was the prospective analysis of Wallerian degeneration of the pyramidal tract after paramedian pons infarction. Methods: Patients with paramedian pons infarct underwent MR imaging including diffusion tensor imaging at admission and got 1–3 MR scans up to 6 months of follow-up. Clinical scores and transcranial magnetic stimulation were acquired in the acute phase and 3–6 months later. The pyramidal tracts were manually segmented in fractional anisotropy (FA) color maps after coregistration of all MR datasets of each patient. FA as well as axial and radial diffusivity were measured in the volume of lesioned and contralateral pyramidal tracts distally to the ischemic lesion. Results: From 11 patients studied, 7 developed Wallerian degeneration detected as statistically significant decrease in FA over time in the distal pyramidal tract. Wallerian degeneration could be detected at the earliest between the first and the third days after the onset of symptoms. A continuous decrease in FA and an increase in axial and radial diffusivity in degenerating pyramidal tracts over time were demonstrated. A significant correlation between NIHSS score on admission and the slope of relative axial diffusivity and a significant correlation between motor-evoked potential amplitudes of the arm on admission and the outcome relative FA was found. Conclusions: The initial MR image cannot predict the following Wallerian degeneration. However, the severity of motor disturbance and the motor-evoked potential of the arm on admission could be possible parameters to predict Wallerian degeneration. For estimation of Wallerian degeneration over time, at least 2 diffusion tensor imaging measurements have to be done at different time points.

Background and Purpose: We aimed to validate the usefulness of the Essen Stroke Risk Score (ESRS) to predict stroke recurrence in a hospital-based follow-up study. Methods: We followed up 730 consecutive patients admitted to a neurological stroke unit in Berlin, Germany, with ischemic stroke (IS) or transient ischemic attack (TIA). The mean follow-up time was 13.4 months (SD 5.9). We calculated the time of event-free survival by Kaplan-Meier estimates. Results: The cumulative rate of a recurrent stroke was 10.4% (76 of 730). The risk of a recurrent stroke was significantly higher in patients with an ESRS >2 (p = 0.01; log rank). The area under the curve (AUC) was 0.59. The risk of a vascular event (VE), defined as a fatal or nonfatal IS or myocardial infarction, was significantly higher in patients with an ESRS >2 (p = 0.003; log rank). The AUC was 0.58. Stratifying the data at exact 1-year follow-up, 9 of 185 (10.3%) patients with an ESRS ≤2 suffered a recurrent stroke, while 56 of 311 (18%) patients with an ESRS >2 did so (p < 0.02; χ2). Thirty-six of 196 (18.4%) patients with an ESRS ≤2 suffered a VE, while 156 of 353 (35.7%) patients with an ESRS >2 did so (p < 0.001; χ2). Conclusions: The ESRS identifies groups of patients with TIA or IS who are at significantly increased risk for a recurrent stroke and cardiovascular event. Patients with a high ESRS require short-term follow-up and reevaluation of secondary prevention strategies.

Valproic acid (VPA) is an antiepileptic drug (AED) commonly used for generalized and focal epilepsies. We provide an update on hepatotoxic side effects in Germany between 1994 and 2003.We mailed a questionnaire to all members of the German Section of the International League Against Epilepsy, asking for VPA-induced side effects, especially severe side effects such as hepatopathy.As a result of our questionnaire, we found 31 cases of reversible hepatotoxicity and nine cases of lethal hepatopathies in Germany from 1994 to 2003.The outcome of patients with severe hepatotoxicity is better than that in the past. The risk of a VPA-induced hepatopathy is not limited to patients younger than 2 years, receiving polytherapy, or patients with congenital or acquired metabolic diseases.

Publisher Summary This chapter presents a new method of statistically based three-dimensional (3D) brainstem mapping to identify brainstem structures responsible for specific clinical and electrophysiological abnormalities. To ensure reliable correlations, a large cohort of patients with magnetic resonance (MR)-documented brainstem infarctions were recruited in two European neurological institutions—namely, the Department of Neurology, Johannes Gutenberg University, Mainz, Germany, and the Department of Neurological Sciences, “La Sapienza” University of Rome, Italy. This method minimizes the risk of highlighting vascular territories rather than the structures specifically responsible for the clinical deficit. It allows proper visualization of functional–anatomical correlations in humans. It may also account for the variance of data within the considered population, and it provides a measure of the extent to which the results represent the general population. The model, however, does not ignore completely the vascular supply to the brainstem and areas generally favored by brainstem infarction. Another drawback of the method is that the spatial resolution (2 mm) cannot match the anatomical details of pathological studies.

Publisher Summary The Wallenberg syndrome or dorso-lateral medullary infarction is the most common vascular syndrome of the medulla oblongata. Its clinical features include an ipsilateral Horner's syndrome, an ipsilateral limb ataxia, and mostly an ipsilateral but sometimes also a contralateral or bilateral decrease of pain and temperature sensibility of the face. Patients with Wallenberg's syndrome and with morphological (lesion) or functional (ipsilateral sensory deficit and delayed late blink reflex responses) show evidence of damage to the trigeminal tract and nucleus with sparing of the nucleus caudalis would develop facial pain. The trigeminal trophic syndrome (TTS), a very rare complication of Wallenberg's syndrome, can occur with and without central poststroke pain (CPSP). In these patients, itch is the predominant complaint causing facial ulcerations maintained by picking and scratching. Ongoing itch is a matter of not only neural injury but also missing inhibition. The intensity and duration of scratching provoked by itch are reduced with the onset of pain. The lack of pain sensibility in most patients with itch following TTS may result in this kind of missing inhibition. TTS patients often, but not always, suffer from diseases leading to a reduction of central inhibitory mechanisms, such as dementia or bipolar depression.

To investigate the incompletely understood somatotopical organization of the corticospinal tract in the human brainstem, we performed a voxel-based statistical analysis of standardized magnetic resonance scans of 41 prospectively recruited patients with pyramidal tract dysfunction caused by acute brainstem infarction. Motor hemiparesis was rated clinically and by the investigation of motor evoked potentials to arms and legs. Infarction affected the pons in 85% of cases. We found the greatest level of significance of affected brainstem areas between the pontomesencephalic junction and the mid pons. Lesion location was significantly more dorsal in patients with hemiparesis affecting more proximal muscles and was significantly more ventral in patients with predominantly distal limb paresis. Comparison of magnetic resonance lesion from patients with paresis predominantly affecting arm or leg did not show significant topographical differences. We conclude that a topographical arm/leg distribution of corticospinal fibers is abruptly broken down as the descending corticospinal tract traverses the pons. Corticospinal fibers, however, follow a somatotopical order in the pons with fibers controlling proximal muscles being located close to the reticular formation in the dorsal pontine base, and thus more dorsal than the fibers controlling further distal muscle groups.

Body lateropulsion may occur without signs of vestibular dysfunction and vestibular nucleus involvement. The authors examined 10 such patients with three-dimensional brainstem mapping. Body lateropulsion without limb ataxia reflected an impairment of vestibulospinal postural control caused by a lesion of the descending lateral vestibulospinal tract, whereas body lateropulsion with limb ataxia was probably the consequence of impaired or absent proprioceptive information caused by a lesion of the ascending dorsal spino-cerebellar tract.

Background Recently, a new model of fiber architecture of the linea alba has been described consisting of an oblique fiber layer of intermingling oblique fibers, a transverse fiber layer containing mainly transverse fibril bundles, and a variable, small irregular fiber layer. In this study the morphological model was proven using direction-specific biomechanical measurements of the linea alba. Material and methods Thirty-one human abdominal walls were analyzed (16 male and 15 female). Six strips of collagen tissue with a width of 1 cm were exsected from each linea alba transversely, obliquely, and longitudinally according to the main fiber directions. An increasing force from 2 to 24 N was applied to these strips, and the corresponding strain represented by the relative elongation was measured, which allows the calculation of a direction-specific compliance of the tissue. Results The compliance is highest in longitudinal and smallest in transverse direction. In the infraumbilical part of the female linea alba the compliance was significantly smaller in the transverse direction than in the oblique direction. Moreover, the compliance in the transverse direction was significantly smaller in women than in men. Conclusions A distinct anisotropy of morphological and biomechanical properties was demonstrated as well as sex-dependent differences. The compliance correlates with the distribution of fiber orientation in the linea alba. These biomechanical results constitute the functional correlation with the fiber morphology of the linea alba and correspond well to our earlier proposed model of fiber architecture.

Spontaneous intracranial hypotension (SIH) is known to cause postural headache, often combined with auditory, and vestibular symptoms, nausea, vomiting, and diplopia. We report a 63-year-old male patient who for the first time developed a depressive episode followed by acute manic symptoms during the course of SIH, both relieved after treatment of the underlying organic disturbance.

It is occasionally necessary to repeat diffusion weighted imaging (DWI) after giving intravenous contrast medium (CM). However, the effects of CM on DWI and apparent diffusion coefficients (ADC) have not been fully examined. The aim of this prospective study was to investigate whether there are any diagnostically significant differences between echo-planar imaging (EPI)-DWI before and after intravenous CM. EPI-DWI was acquired twice in 203 consecutive patients before and after i.v. CM. Three blinded readers rated the diagnostic image quality. Quantitative ADC calculations were performed before and after CM in all 72 patients with lesions sufficiently large for quantification, and in 72 normal brain regions. Of the 203 patients, 127 had abnormalities on MRI, including ischaemic stroke (52), bleeding (nine), brain tumour with disturbed blood-brain barrier (BBB) (18) and other lesions (48). There were no significant signal differences on isotropic DWI before and after CM, even in lesions with definite disturbance of the BBB. No statistically significant difference between ADC of lesions and contralateral normal brain was observed.

The aim of this study was to evaluate the sensitivity of multimodal electrophysiological brainstem testing in the diagnosis of clinically suspected reversible ischemic deficits of the brainstem compared with diffusion weighted MR imaging. We investigated 158 consecutive patients presenting with signs of acute brainstem dysfunction. Serial electrophysiological brainstem tests including masseter reflex, blink reflex, masseter inhibitory reflex, AEP, MEP, EOG and the oculoauricular phenomenon were applied. In 14 of the 158 patients neurological deficits resolved in less than 24 hours, which was suggestive of a transitory ischemic attack (TIA), 19 patients had brainstem signs for more than 24 hours but less than 1 week, suggestive of a reversible ischemic neurological deficit (RIND). Electrophysiological data indicated acute functional brainstem lesions in 54,5 % of patients with transient clinical brainstem impairment. Lesion detection rate was significantly higher when combining electrophysiological data and MRI (60,4 %) than using acute brainstem abnormalities in diffusion weighted MRI alone (39,4 %). We conclude that diffusion weighted MRI and electrophysiological brainstem testing are complimentary sensitive indicators of acute brainstem lesions in patients with reversible neurological deficits. Correct identification of brainstem ischemia influences the therapeutic regimen and may improve patient outcome.

Objectives: To evaluate the sensitivity of diffusion weighted magnetic resonance imaging (MRI) for the diagnosis of clinically suspected reversible ischaemic deficits of the brainstem. Methods: A total of 158 consecutive patients presenting with acute signs of brainstem dysfunction were investigated using EPI diffusion weighted MRI within 24 hours of the onset of symptoms. High resolution T1 and T2 weighted imaging was performed as a follow up after a median of six days Results: Fourteen of the 158 patients had a complete clinical recovery within 24 hours (transitory ischaemic attack (TIA)), and 19 patients recovered in less than one week (prolonged reversible neurological deficit (RIND)). Diffusion weighted MRI showed acute ischaemic deficits in 39% of patients with transient neurological deficits. The detection rate seemed to be higher in patients with longer lasting symptoms, but the difference between patients with TIA (29%) and RIND (47%) was not significant. Conclusions: Diffusion weighted MRI is a sensitive indicator of acute ischaemic brainstem deficits even in patients with reversible neurological deficit. Early identification of patients with TIA and increased risk of stroke may influence acute management and improve patient outcome.

diffusion weighted magnetic resonance imaging (MRI) is highly sensitive in detecting acute supratentorial cerebral ischemia and Diffusion Weighted Imaging (DWI) lesion size has been shown to correlate strongly with the neurologic deficit in middle cerebral artery territory stroke. However, data concerning infratentorial strokes are rare. We examined the size and evolution of acute brain stem ischemic lesions and their relationship to neurological outcome.brain stem infarctions of 11 patients were analyzed. We performed DWI in all patients and in 7/11 patients within 24 h, T2W sequences within the first 2 weeks (10/11 patients) and follow-up MRI (MR2) within 3-9 months (median 4.8 months) later (12/12 patients). Lesion volumes were compared with early and follow-up neurologic deficit as determined by National Institutes of Health Stroke Scale (NIHSS) score.the relative infarct volumes--with MR2 lesion size set to 100%--decreased over the time (P0.02) with a mean shrinking factor of 3.3 between DWI (MR0) and the follow-up MRT (P0.02), and 1.6 between early T2W (MR1) and MR2 (P0.04). The mean DWI volume size (MR0) was larger than the early T2W (P0.02). Although neurological outcome was good in all patients (mean NIHSS score of 1.3 at follow-up), early NIHSS and follow-up NIHSS scores were strongly correlated (r=0.9, P0.00). NIHSS score at follow-up was highly correlated with lesion size of DWI (MR0; r=0.71, P0.04) and T2W of MR1 (r=0.86, P0.001).in this study, we saw a shrinking of the brain stem infarct volume according to clinical improvement of patients. Great extension of restricted diffusion in the acute stage does not necessarily implicate a large resulting infarction or a bad clinical outcome.

The aim of the study was to investigate the relation of the blink reflex R1 arc to known anatomical brainstem structures. Acute vascular brainstem lesions as identified by magnetic resonance imaging (MRI) of patients with isolated R1 pathology were superimposed into a stereotactic anatomical atlas using a new method of digital postprocessing. Isolated acute brainstem lesions were documented by diffusion-weighted MRI in 12 of 24 patients with unilateral R1 pathology. The lesions were located in the ipsilateral mid- to lower pons. In three patients only, the lesion had partial contact with the principal sensory nucleus of the trigeminal nerve (PSN) on at least one level. In two patients, the lesion involved the medial longitudinal fasciculus. Most lesions were located medially and ventrally to the PSN on transverse slices. Our results underline the high localizing value of changes in the R1 component of the blink reflex in patients with ipsilateral pontine functional deficits. Although available physiological evidence suggests that the R1 component of the blink reflex traverses an oligosynaptic pathway, this MRI study does not support the view that synaptic transmission in the PSN subserves R1. The reflex arc probably descends more medially and ventrally on its course to the facial nucleus. © 2001 John Wiley & Sons, Inc. Muscle Nerve 24: 1327–1331, 2001

Background and purpose: Although dysarthria is a frequent symptom in cerebral ischemia, there is little information on its anatomic specificity, spectrum of associated clinical characteristics, and etiologic mechanisms. Methods: An investigation of 68 consecutive patients with sudden onset of dysarthria due to a single infarction confirmed by MRI or CT was conducted. Results: Dysarthria was associated with a classic lacunar stroke syndrome in 52.9% of patients. Isolated dysarthria and dysarthria–central facial and lingual paresis occurred in 2.9% (n = 2) and 10.3% (n = 7), respectively. Dysarthria–clumsy hand syndrome was observed in 11.7% (n = 8) of patients and associated with pure motor hemiparesis and/or ataxic hemiparesis in 27.9% (n = 19). The lesions were due to small-vessel disease in 52.9% (n = 36), to cardioembolism in 11.8% (n = 8), and to large-vessel disease in only 4.4% (n = 3) of cases. Infarctions were located in the lower part of the primary motor cortex (5.9%; n = 4), middle part of the centrum semiovale (23.5%; n = 16), genu and ventral part of the dorsal segment of the internal capsule (8.8%; n = 6), cerebral peduncle (1.5%; n = 1), base of the pons (30.9%; n = 21), and ventral pontomedullary junction (1.5%; n = 1). Isolated cerebellar infarctions affected the rostral paravermal region in the superior cerebellar artery territory. Conclusions: Extracerebellar infarcts causing dysarthria were located in all patients along the course of the pyramidal tract. This finding correlates with the frequent occurrence of associated pyramidal tract signs in 90.7% (n = 62) of patients. Isolated cerebellar infarcts leading to dysarthria were in all cases located in the territory of the superior cerebellar artery.

SummaryValproic acid (VPA) is a broad-spectrum antiepileptic drug and is usually well-tolerated. Rare serious complications may occur in some patients, including haemorrhagic pancreatitis, bone marrow suppression, VPA-induced hepatotoxicity and VPA-induced encephalopathy. The typical signs of VPA-induced encephalopathy are impaired consciousness, sometimes marked EEG background slowing, increased seizure frequency, with or without hyperammonemia.There is still no proof of causative effect of VPA in patients with encephalopathy, but only of an association with an assumed causal relation. We report 19 patients with VPA-associated encephalopathy in Germany from the years 1994 to 2003, none of whom had been published previously.

We present the unique case of a patient with a circumscribed solitary cerebral metastasis of a malignant melanoma extending from the medial part of the superior temporal gyrus to the lower part of the 1st long insular gyrus causing gait and stance instability and an ipsiversive tilt of the subjective visual vertical. Oculomotor disorders could not be detected. We suggest that the superior temporal gyrus is likely to be involved in spatial orientation presumably using otolithic information.