[Arachnoid cyst and tension headache: symptom or accidental finding?]. / Arachnoidalzyste und Spannungskopfschmerz Symptom oder Zufallsbefund?

We report a 34 year old male patient presenting with occipital headache and bilateral shoulder and neck pain. Cranial MRT discloses a large arachnoid cyst ventral to the medulla oblongata. The cyst displaces the caudal medulla oblongata dorsally to an angle of almost 90 degrees without causing myelopathy. Physical examination reveals normal neurological findings without any sign of brainstem lesions or lesions of the medulla oblongata. Orthopedic evaluation shows mild functional abnormalities as expected in tension headache. Multiple electrophysiologic investigations such as motor-, somatosensory-, and acoustic-evoked potentials, masseter and brain stem reflexes, and electromyography of the left M. trapezius were performed and reveal normal results. MR-angiography discloses displacement of the left vertebral artery to the right without stenosis.We discuss the possibility of a causal connection between the cystic lesion and the reported symptoms. Considering the findings based on a review of the available literature we conclude that the pain syndrome is very likely unrelated to the arachnoid cyst. The latter is herewith an accidental finding in a patient with tension headache, and underlines the importance of thoroughfull clinical examination to avoid unnecessary diagnostic or therapeutic procedures.

[Cerebral vasculitis as the initial manifestation of systemic lupus erythematosus]. / Zerebrale Vaskulitis als Erstmanifestation eines systemischen Lupus erythematodes.

HISTORY AND CLINICAL FINDINGS: A 41-year-old man was admitted to the hospital because of a series of seizures. History revealed increasing weakness and generalized myalgia following a severe respiratory tract infection three months previously. The clinical examination was dominated by reduced alertness and cognitive impairment. INVESTIGATIONS: Positive ANA titres pointed to an autoimmune disease; further laboratory tests revealed an antiphospholipid syndrome. The clinical diagnosis of systemic lupus erythematosus was supported by renal biopsy. Transcranial Doppler sono-graphy and magnetic resonance imaging with angiography revealed cerebral vasculitis with multiple intracerebral grey and white matter lesions. TREATMENT AND COURSE: In addition to an immunosuppressive therapy with corticosteroids and intravenous pulses of high-dose cyclophosphamide, oral anticoagulation was given in order to prevent thromboembolic complications. Seizures were treated with valproate. A follow-up MRI revealed multiple glial cell reactions and reduced vasculitic changes. CONCLUSIONS: Initial neuropsychiatric symptoms and seizures prompted the diagnosis of systemic lupus erythematosus with cerebral vasculitis in a 41-year-old patient. Approximately 20 % of all lupus patients initially present with neuropsychiatric disorders. Central nervous system involvement and renal complications determine the course and prognosis of the disease as well as therapeutic decisions. Particularly in young patients with neuropsychiatric symptoms systemic lupus erythematosus should be excluded routinely.

[Quality assurance in treatment of stroke: basic module of the German Stroke Registry Study Group]. / Qualitätssicherung in der Schlaganfall-Behandlung: das Basismodul der Arbeitsgemeinschaft Deutscher Schlaganfall-Register (ADSR).

BACKGROUND AND PURPOSE: Comparable, standardised data on the quality and efficiency of stroke care in Germany are lacking. The Arbeitsgemeinschaft Deutscher Schlaganfall-Register (ADSR--German Stroke Registries Study Group) has defined a "Minimum DataSet" for the evaluation of quality indicators of stroke treatment in Germany. METHODS: The ADSR is a voluntary network of current regional stroke registries aiming at a standardisation in the use of stroke terminology and methods of data collection for German stroke databases. Currently six regional stroke registries are cooperating in the ADSR, combining data from about 18,000 stroke patients in 110 hospitals annually. RESULTS: In the design of the ADSR DataSet a modular approach was chosen. The ADSR "Minimum DataSet" was adapted for a wide use in different health care facilities. In addition to the "Minimum DataSet" an "Advanced DataSet" will be developed to document additional items of stroke care in specialised stroke centres. The ADSR DataSet collection will be completed by special "Extended DataSets", designed for answering centre-specific and research questions. CONCLUSION: The ADSR "Minimum DataSet" allows a standardised assessment of stroke care in Germany. It is the first questionnaire that provides valid and reliable comparisons between different clinical settings as well as regional stroke databases. The ADSR "Minimum DataSet" defines core items for a future National German Health Report on stroke care.

Cerebrospinal fluid hypoxanthine, xanthine and uric acid levels may reflect glutamate-mediated excitotoxicity in different neurological diseases.

Glutamate-mediated excitotoxicity is associated with adenosine triphosphate (ATP) degradation and generation of oxygen radicals. Hypoxanthine and lactate depict energetic impairment, while xanthine and uric acid reflect activity of radical producing xanthine oxidase. Cerebrospinal fluid (CSF) glutamate, hypoxanthine, lactate, xanthine, and uric acid were investigated in neurological patients. In multiple sclerosis, myelopathy, stroke, epilepsy and viral meningitis glutamate, hypoxanthine, xanthine, and uric acid are increased 2-3-fold compared to controls. Lactate is only elevated in meningitis. Normal lactate dehydrogenase (LDH) levels and absent correlation between the albumin ratio and neurochemical parameters exclude an artificial increase due to cell lysis and barrier damage. Absent correlation between neurochemical parameters within each patient group is most likely related to preserved glial and neuronal uptake mechanisms. CSF hypoxanthine, xanthine, and uric acid levels appear superior to lactate in reflecting glutamate-mediated excitotoxicity in neurological patients.

Neurotransmitters in cerebrospinal fluid reflect pathological activity.

The excitatory transmitters glutamate and aspartate become toxic whenever their extracellular levels are increased because of neuronal, glial and endothelial impairment. Taurine, a volume-regulating amino acid, is released upon excitotoxin-induced cell swelling. Our aim was to investigate if glutamate and aspartate in cerebrospinal fluid (CSF) reveal neuropathology in neurological patients, and if taurine unmasks glutamate-mediated toxicity. Glutamate and aspartate are doubled in viral meningitis, acute multiple sclerosis (MS) and myelopathy compared with control subjects and patients with peripheral facial nerve palsy. These levels do not coincide with a disturbed blood-brain barrier, as estimated by the albumin ratio, are independent of their precursors (glutamine, asparagine) and are not associated with cell lysis. Taurine is significantly increased in meningitis, acute MS, and myelopathy, suggesting glutamate-mediated toxicity. Analysis of transmitters in lumbar CSF can be used to identify patients with cerebral and spinal pathology who might benefit from specific receptor-modulating agents.

Auditory brain stem responses in patients with human immunotropic virus infection of different stages.

Thirty patients (26 men, 4 women) with human immunotropic virus infection of different stages were examined. Eleven patients had a history of i.v. drug abuse, nine patients had a history of treated lues infection, and one patient suffered from Kaposi's sarcoma. At the time of the examination, opportunistic infections or acute encephalitis were not apparent in any patient. All patients underwent otoneurological examinations, including pure-tone audiometry, caloric vestibular testing, and recording of the auditory brain stem responses (ABR). Six patients reported onset of hearing impairment during the last 3 yr. Two of them had flat sensorineural hearing loss; in the other cases, pure-tone audiometry showed high tone hearing loss with negative recruitment. ABRs were normal in 19 cases, with the latencies for waves III and V and for the I-V interpeak latency significantly delayed when compared to the values of the control group. The frequency of abnormal ABR findings did not correlate to the stage of the disease. The results of the study indicate that auditory and, more specifically, ABR abnormalities commonly occur in human immunotropic virus disease. More studies are necessary to prove whether the ABR is suitable to monitor therapeutic effects.

[Pattern-reversal visual evoked potentials and electroretinography in the early diagnosis of chronic simple glaucoma]. / VEP und Elektroretinographie durch Musterumkehrreizung in der Frühdiagnostik des Glaucoma chronicum simplex.

For differential, therapeutic, and prognostic reasons the recognition of early lesions in glaucoma chronicum simplex is very important. Besides sophisticated ophthalmological investigations optic nerve and retinal functions can be tested by flash and pattern-reversal evoked visual potentials and electroretinograms. 38 glaucomatous eyes were investigated by VEP and ERG applying single and flicker flashes as well as transient pattern-reversal stimuli of different check sizes. The results related to the degree of visual field disturbances show the damage of retinal and neuronal elements in a descending order affecting first of all the macular cones, then the rod system, and later on the elements of the second retinal neuron. The ganglion cells seems to be affected after all.

[Shape changes in contrast VEP in multiple sclerosis: relation to the type of lesion]. / Formveränderungen des Kontrast-VEP bei multipler Sklerose: Beziehung zum Läsionstyp.

VEP changes in MS patients are due to the demyelinating process which causes conduction alterations as well as inhibitory mechanisms. The pattern-shift VEP can show a delay of the main positivity, a diminished amplitude or/and an altered shape and duration. Concerning to series from the literature and own observations on more than 500 MS patients 4 different types of VEP alterations can be observed: 1. NPN complex with P2 delay; 2. broadening with loss of N2 and P2 delay; 3. bifid P2, P100-P135 complex; 4. deformation and dissociation with loss of P2, N105 dominance and amplitude reduction.

[The dependence of phase inversion of the visual evoked potential during half-field stimulation on the stimulation target and the pattern size]. / Abhängigkeit der Phaseninversion des VEP bei Halbfeldreizung von Reizort und Mustergrösse.

In 10 young and healthy subjects visual evoked potentials were recorded to monocular whole-field and half-field (12 degrees radius) stimulation, with and without central (3 degrees radius) and peripheral occlusion of the target. The records were made from a horizontal array of 3 occipital electrodes, one placed in the midline 5 cm above the inion and the others 8 cm each lateral of the inion. The early and main components of the VEPs were analyzed and compared. We found that the N2-Peak has its origin in the macular parts of the retina and the P2-peak in the central and peripheral parts of the visual field. Inverted polarity of the P2-peaks contralateral to the stimulated half-field could be observed only when the VEP was recorded with small checks. When using large checks, only the early components inverted. The probable origin of the inverted main components is discussed, being either a simple inverted P2-peak because of the direction of the cortical dipoles, or a new, paramacular N105-peak.

[Pattern reversal VEP and computer perimetry of the partner eye in optic neuritis]. / Musterumkehr-VEP und Computerperimetrie am Partnerauge bei Optikusneuritis.

The pattern-reversal VEP with different check size and the computerized perimetry in the 10 degrees and 30 degrees radius field were recorded in 22 patients suffering from unilateral optic neuritis diagnosed by historical as well as by clinical findings. During the acute attack 12/22 optic neuritis eyes and 3/22 partner eyes had a diminished visual acuity below 0.7. After the attack the visual acuity remained reduced in 9/22 of the affected and 2/22 of the nonaffected partner eyes. The VEP was prolonged in 19/22 optic neuritis eyes and in 12/22 partner eyes applying 50' checks and in 15/22 resp. applying 15' checks. The computed visual fields showed depressions in 21/22 optic neuritis-eyes and in 15/22 partner eyes within in the 30 degrees radius field. VEP and computerized perimetry, there for, can detect subclinical affections of partner eyes in unilateral optic neuritis in a very high percentage.

Habituation of the blink reflex: computer assisted quantitative analysis.

The electrically evoked blink reflex (BR) was elicited in 20 healthy volunteers, varying the stimulus interval by a computer JN 110. Latencies, amplitudes, reflex duration and reflex areas of early and late components of the BR were analysed by a computer program testing the signal-to-noise ratio, the response configuration and frequency distribution. Changes in habituation related to the stimulus interval can be illustrated best by the progressive diminution of R2 areas. Computing the habituation in relation to the stimulation frequency by a standardized program seems to be a quantitative method to assess habituation in various diseases and during treatment studies.

Isometric muscle contraction in endocrine myopathies.

Isometric contraction of the adductor pollicis muscle of the thumb was evoked by stimulating the ulnar nerve in 20 normal adults and 58 patients with endocrine disorders. We evaluated mechanical latency, electromechanical latency, contraction time, half relaxation time, isometric twitch force, compound muscle action potential, nerve conduction velocity, and relative refractory period. Mechanical characteristics were altered in diseases of the pituitary, thyroid, and parathyroid glands. The close relationship between thyroid hormone and contractile properties discriminated between hypo- and hyperthyroidism.

Early auditory evoked potentials: developmental aspects and validity in neuropaediatric and audiologic disorders.

Auditory evoked potentials and in this context especially five waves in the first 10 ms (early auditory evoked potentials = EAEP) are a diagnostic aid in topodiagnosis of posterior fossa diseases. This is due to waves I to V which arise along the acoustic nerve and in brain stem structures such as medulla, pons and mid-brain. Besides an indication about the site of a lesion in the posterior fossa, wave V allows an objective threshold determination. The present results were gained in normal children aged 1-3 years and in children with neuropaediatric and audiologic disorders.

[Normalization of VEP in multiple sclerosis? Course observation in 50 of 500 MS patients]. / "Normalisierung" des VEP bei Multipler Sklerose? Verlaufsbeobachtung bei 50 von 500 MS-Patienten.

Serial recordings of pattern-reversal VEPs have been performed in 50 of 500 MS patients in 4 or more occasions within the last 5 years. 49/96 eyes initially displayed a normal and 47/96 a prolonged P2 latency. A further delay was observed in 9 eyes, while in another 9 eyes the latency improved entering the normal range but in 4 eyes. In two eyes, only, shape and peak configuration normalized too. These results demonstrate the rarity of true normalisation of the contrast VEP after optical neuritis in MS.

[Pattern reversal VEP in TV and moving-mirror stimulation: a methodological comparison]. / Musterumkehr-VEP bei TV- und Drehspiegelreizung: ein methodischer Vergleich.

Pattern-Reversal visual evoked potentials (VEP) were elicited in 10 controls by optomechanical and TV-reversal. TV-stimulation was done in the frame-locked and -unlocked mode. Comparing P2-latencies evoked by different stimulation fields of the screen delays up to 30 ms and increased standard deviations could be observed in the TV-stimulation modes. Moreover, stimulating with small checks a diminution of amplitudes and a simplification of the shape was seen in contrary to the mirror method.

Hemifacial spasm: location of the lesion by electrophysiological means.

In hemifacial spasm a late abnormal motor response was elicited by the antidromic volley after stimulating a peripheral branch of the facial nerve. The site of the lesion was calculated from the latency of that motor response and the conduction velocity. In 5 patients the distance was long, and corresponded with a tumor or a vascular anomaly at the cerebellopontine region in 3 of them. An artery sling entering the internal acoustic meatus was found in 2 out of 3 patients with short distances. It is concluded that hemifacial spasm results from a nerve lesion that may be located as far peripherally as the internal acoustic meatus. The theory of facial nuclear irritation is incompatible with such a peripheral lesion.