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Die zervikale Dystonie verursacht eine schwere Beeinträchtigung des Patienten und ist medikamentös nicht effektiv behandelbar. Die Standardtherapie ist die wiederholte Injektion von Botulinum-Toxin in die dystone Halsmuskulatur. Wenn diese Therapie versagt (meist wegen Antikörperbildung), kommt die tiefe Hirnstimulation in Betracht.Wir berichten über die Erfahrungen mit 8 Patienten, bei denen der Tortikollis durch die beidseitige Implantation von Stimulationselektroden in den Globus pallidus internus behandelt wurde. Der Beobachtungszeitraum betrug im Mittel 31 Monate.Die Besserung trat bei 6 der 8 Patienten innerhalb weniger Tage auf und betrug im Mittel aller Patienten im ersten Jahr 60%. Komplikationen wurden nicht beobachtet.Die tiefe Hirnstimulation hat in dieser und in anderen Studien mit kleiner Fallzahl eine gute Wirksamkeit bei der zervikalen Dystonie gezeigt. Nach unseren Ergebnissen profitieren besonders Patienten, deren Symptomatik nicht zusätzlich die Schultermuskulatur betrifft und die eher eine tonisch-dystone und keine klonisch-dystone Symptomatik haben. Diese und die Ergebnisse anderer machen es sehr wahrscheinlich, dass sich die Hirnstimulation als Behandlung der Wahl beim anderweitig therapierefraktären Tortikollis etablieren wird.Cervical dystonia results in severe disability and cannot be effectively treated with medication. Repeat injections of botulinum toxin into the dystonic neck muscles can relieve the symptoms in most patients. When this treatment fails (mostly due to antibody formation), deep brain stimulation can be considered.We report our experiences with eight patients who were treated with bilateral deep brain stimulation of the globus pallidus interna for cervical dystonia. The mean observation period was 31 months.Six of eight patients experienced relief from symptoms a few days after the implantation. Improvement of symptoms was a mean of 60% during the 1st year. There were no complications.In this and in other studies with small numbers of patients, deep brain stimulation has shown a good effect on cervical dystonia. According to our results, the patients who benefit most are those with no dystonic shoulder involvement and who have a tonic rather than clonic symptomatology. It seems probable that deep brain stimulation will become the therapy of choice for otherwise intractable cervical dystonia.

Clinical signs help determine correct electrode positioning during stereotactic implantation for chronic high-frequency pallidal stimulation in Parkinson’s diease (PD). The authors describe a patient who had marked, sustained, contraversive eye deviation caused by stimulation during pallidal surgery. The underlying mechanism is probably an excitation of fibers in the internal capsule by volume-conducted current spread. Such conjugate eye deviation is thus not necessarily an indication of incorrect electrode placement.

Zusammenfassung: Die Diagnose der seltenen Gliomatosis cerebri kann nur in Zusammenschau von klinischen, radiologischen und histopathologischen Befunden gestellt werden. Im vorliegenden Artikel berichten wir über 2 Patienten, bei denen intra vitam nach stereotaktischer Hirnbiopsie die Diagnose Gliomatosis cerebri gesichert wurde. Da in beiden Fällen für Gliomatosis cerebri ungewöhnlich hochgradig entdifferenzierte Tumorzellen vorlagen, wurde die Diagnosefindung durch atypische Befunde wie Kontrastmittelaufnahme im MRT und klinische Zeichen der intrakraniellen Drucksteigerung erschwert. Klinischer Verlauf, Differentialdiagnosen und Literatur werden kurz dargestellt.

In three different experimental series, electroencephalographic responses evoked by changes in pictorial patterns were recorded in 29 adult human subjects (19 females, 10 males). Quantitative data evaluation for the evoked responses from electrodes T5, T6, Cz, Pz (10–20 system) was performed. The stimuli were projected to a 4 × 6 degree binocularly viewed field. The patterns changed within 6 ms every 2.5–4.5 s according to a random program. Paradigm (1): Identical line drawings of a face, a tree and a chair were used, either black on white (P-stimuli) or white on black (N-stimuli); in each set altogether 160 slides appeared in semi-random order. At Cz and Pz a prototypical EEG-response evoked by face stimuli was found exhibiting 3 prominent peaks, very similar for P-stimuli and N-stimuli. A P150 maximum was especially pronounced in the responses to face stimuli but absent in the evoked potentials aroused by chair or tree stimuli. The difference curves (face-chair, face-tree, chair-tree) supported the hypothesis of “face-responsive” components in these responses. Paradigm (2): 4×6 degree slides (black and white photographs) of 54 different human faces, 53 different vases and 53 different pairs of shoes were projected as in paradigm (1), but instruction to the subjects on a supposed post-test memory task raised their attention during the recordings. “Face-responsive” components (an early N 140–160, P 210–240, N 300) were more marked in female than in male subjects, and again most pronounced at electrode Cz. Paradigm (3): When a recognition task was included in paradigm (2) — 9 out of 192 items were memorized 20 minutes before the recording session — essentially the same evoked potentials were obtained as in (2), but an additional late positive wave (450–600 ms) appeared in the responses to all stimuli. We assume that the “face-specific” components — a designation which is used cautiously considering the limited number of non-face stimuli — do not originate in the temporo-occipital cortical face region, but in limbic structures (amygdala, hippocampus) deep in the temporal lobe or in the gyrus cinguli. In the present study no significant hemispheric differences (T5, T6) in the evoked responses were found (all stimulus categories), but such differences are known to appear with highly schematic face stimuli.

Abstract:  The cerebral events related to limb movements can be studied noninvasively with the method of evoked potentials. In this study, a brain potential is analysed that follows the onset of a simple finger movement. Because this potential occurred after active as well as after passive movements, its previously alleged reafferent somatosensory nature is confirmed in this study. Detailed topographic analysis revealed that this potential has the same polarity and merges with the preceeding Bereitschaftspotential (BP; in the active movement) at central electrodes, whereas at parietal electrodes polarity is opposite to the BP. In individual subjects, the maximum of the BP and the peak of the reafferent potential are separated by a small gap, previously described as pre-motion positivity. A comparison with the N20 potential of the electrically evoked somatosensory potential showed similar potential topography, albeit opposite polarity. The dipole analysis supported the view that the reafferent and the electrically evoked potentials are likely to arise from the same cortical area, namely the primary somatosensory cortex.

Initial saccades to visual targets are generally not precise in either normal subjects or patients with saccadic dysmetria. Quantitative criteria have to be applied to clearly distinguish between normal and pathological saccadic dysmetria, which is often found in patients with cerebellar lesions. To establish these criteria, the accuracy of visually guided horizontal saccades (10° and 20° target steps) was studied in a group of 24 patients with lesions affecting the cerebellum or its connections, and compared with data from 17 normal subjects. Eye movements were recorded with infrared oculography. Saccades of normal subjects had an average gain of 0.92–0.95 depending on the stimulus condition. Centripetal saccades were significantly larger than centrifugal saccades, for 20° target steps. Most patients (n = 15) had significantly larger saccadic amplitudes than normal subjects (hypermetria), at least in one direction. Saccades in the opposite direction could be either hypometric, hypermetric or normal. Two patients had hypometric saccades in both directions. For one of the patients with hypermetria, in addition, the amplitude difference between centrifugal and centripetal saccades was significantly larger than in the normal subjects. Five patients had no significant pathology of the initial (primary) saccade, but a pathological pattern of corrective saccades. Two patients had normal saccades under all conditions. The quantitative comparison with normal subjects allows the detection even of mild pathology. According to our results, a pathology can be assumed when the average gain of saccades in at least one direction is 1.0 or more, or when more than two out of 20 saccades are followed by two corrective saccades of which the last is in the direction opposite to the initial saccade (pathological pattern of corrective saccades). Target steps of 20° reveal a pathological condition more often than 10° target steps. The application of quantitative criteria might be useful to establish a diagnosis of pathologic saccadic dysmetria even in instances in which it is clinically not obvious.