Does age influence early recovery from ischemic stroke? A study from the Hessian Stroke Data Bank

Age is the most important risk factor for developing a stroke. In addition, age may also influence stroke recovery. To allow structured discharge planning, it may be important to consider the influence of age on stroke recovery during the early phase. We studied the effect of patient age on early stroke recovery in a cohort of 2219 unselected stroke patients. Data on functional status (Barthel Index Score) were collected prospectively within 24h after admission, after one week and at discharge for 2219 acute stroke patients treated in 1999 and 2000 at 7 neurological departments in the county of Hesse, Germany. Multiple regression analyses were used to test for an association between age, relative recovery and speed of recovery of ADL after stroke. More than half of the patients (58 %) improved in functional status during hospitalization. 37 % had no change in Barthel Index score and only a small number of patients (5 %) deteriorated during this period. Relative improvement decreased with increasing age: patients younger than 55 years showed an improvement of 67 % of the maximum possible improvement compared whith only 50 % for patients above 55 years (adjusted R(2) = 0.120, beta(age) = -0.130, p < 0.001). Age only had a small effect on the speed of recovery. For younger patients functional recovery was slightly faster (adjusted R(2) = 0.256, beta(age) = -0.080, p < 0.001). Despite its strong influence on case fatality, age is a poor predictor of functional recovery during the very early phase after stroke. Resulting functional recovery depends much more on the extent of the initial disability. Advanced age should not be regarded as a limiting factor in the early rehabilitation of stroke patients.

[Multiple cerebral infarcts caused by spontaneous, synchronous cholesterol embolisms]

We report on a 68-year-old patient who was admitted with hemiparesis and disorientation. Computed tomography showed several old, mostly lacunar infarcts. One week after admission, the patient became comatose. A repeat computed tomography revealed several new hypodense lesions in both hemispheres compatible with acute cerebral infarctions. Autopsy confirmed the diagnosis of numerous acute encephalomalacias of the same age which were found in different territories of the anterior cerebral circulation. Histologic examination showed the extraordinary result of multiple cholesterol emboli with a maximum in the peripheral leptomeningeal vessels. The source of the emboli was severe atherosclerosis with an ulcerated and thrombotic surface of the aorta and both carotid arteries. This case is remarkable because of its severe and synchronous emboli of cholesterol in several different cerebral territories. One has to suspect a so far unknown physical or metabolic factor responsible for the shower of emboli.

The stimulus intensity modifies the blink reflex recovery cycle in healthy subjects and in blepharospasm

OBJECTIVE

The excitability of human brainstem interneurons is measured by the blink reflex recovery cycle and is abnormal in blepharospasm. We wondered whether the results of this paradigm depend on the stimulus intensity.

METHODS

We investigated the blink reflex recovery cycle in 13 healthy control subjects and in 13 patients with blepharospasm (7 of them treated with botulinum toxin) using 4 levels of stimulus intensity (5, 12, 19 and 26 mA) and two interstimulus intervals (ISIs, 150 or 250 ms).

RESULTS

In all groups the inhibition of the second R2 response was reduced with strong stimulus intensities: In controls, the inhibition of the second R2 decreased significantly (e.g. young controls, ISI 150 ms, from 89.6+/-15.6% at 5 mA to 21.9+/-49.7% at 26 mA, mean+/-standard deviation). In patients the R2 inhibition found at 5 mA was converted in an R2 facilitation at 26 mA, irrespective of the status of treatment. In addition, the patients' results at 5 mA did not differ significantly from the controls' results at 26 mA.

CONCLUSIONS

The R2 inhibition and its sensitivity to detect abnormal interneuronal excitability depend on the stimulus intensity, which may act by modifying the excitability of the R2 interneurons.

[Australian Refined Diagnosis Related Groups. Formal and inherent problems of grouping with the example of stroke care]

BACKGROUND AND OBJECTIVES

With the Health Reform 2000, the Australian Refined Diagnosis Related Groups (AR-DRG), Version 4.1 have been chosen as the basis for the future German costing system for hospitals. With regard to Stroke Severity (Barthel Index [BI]) we investigated to what extent the grouping according to AR-DRGs can reproduce healthcare expenditures for such patients. Options to adapt and optimize the system are discussed.

PATIENTS AND METHODS

632 patients who had suffered a cerebrovascular accident and were discharged from conservative acute care in 1999, were classified according to the AR-DRGs. For the grouping we alternatively used data from the current hospital information system and a stroke database for quality assurance. The results were also compared with the clinical profiles for the public hospital sector of the corresponding DRGs in Australia (1997-98).

RESULTS

On average 0.99 additional diagnoses per case were documented in the hospital information system, compared to 3.65 in the stroke database. In the stroke database 177 cases (36.8%) were assigned to the DRG with the highest cost weight. 53.7% of these patients suffered a serious stroke (BI < 30). Grouping on the basis of hospital information system data led only to 14 cases (2.8%) assigned to the DRG with the highest cost weight.

CONCLUSIONS

Type and extent of additional diagnoses are crucial for the grouping process. From a clinical and economic point of view, measures of disability and impairment should be assigned to the grouping process to improve homogeneity under both aspects. Scores can also serve for determining reliable outcome parameters. For the development of an outcome related reimbursement system, procedures must be included in the definition of medical DRGs. In future, DRGs, which cover overlapping healthcare sectors, should be developed for patients with poststroke rehabilitation.

Botulinum toxin for treatment of craniofacial hyperhidrosis

The effect of botulinum toxin A (BTX) was studied on 12 patients with idiopathic craniofacial hyperhidrosis. After confirming the diagnosis by Minor's iodine starch test we first treated one-half of the forehead with an injection of 2.5-4 ng BTX (Dysport) equidistantly intracutaneously. After 4 weeks we assessed the efficacy by another Minor's iodine starch test and then treated the other half. Another 4 weeks later a standardized telephone interview was carried out. After 1-7 days the craniofacial sweating in the area injected had completely ceased in 11 patients and was mildly reduced in the remaining one. The efficacy was confirmed by repeated Minor's iodine starch tests. Mild weakness of frowning was the only side effect, lasting 1-12 weeks and completely resolving in all patients. Although sweating has not yet recurred in most patients at follow-up periods up to 27 months, one patient had a relapse 9 months after treatment. Following reports on palmar and axillary hyperhidrosis and gustatory sweating (Frey's syndrome) this is apparently the first report on the use of BTX in the treatment of idiopathic craniofacial hyperhidrosis. BTX seems a promising new treatment for localized hyperhidrosis.

Computed tomographic angiography findings in 103 patients following vascular events in the posterior circulation: potential and clinical relevance

We studied the diagnostic value of computed tomographic angiography (CTA) in the posterior circulation as a noninvasive substitute for intra-arterial digital subtraction angiography (DSA). We prospectively investigated 103 patients with acute stroke in the posterior circulation. All patients underwent CTA and Doppler ultrasound, and DSA was performed in 22 patients. Vascular findings were classified in categories according to the type of lesion and the location in the vertebral, basilar, or posterior cerebral artery. In the first part of the analysis we examined the correlation between CTA and intra-arterial DSA (n=22), and in the second part that between CTA and Doppler ultrasound (n=103). Intra-arterial DSA identified 11 stenoses, 13 occlusions, and 3 hypoplasias. The correlation between DSA and CTA was best for the basilar artery (all lesions were identified with CTA). Of the 14 lesions detected in the vertebral artery by DSA 13 were also detected by CTA, but the specific type of lesion was identified in only 7 cases. The correlation between CTA and Doppler ultrasound was lower. In conclusion, CTA is thus a reliable method for detecting lesions in the posterior circulation and may replace DSA in many cases. However, particularly in the vertebral artery DSA remains the superior technique.

[Involvement of the peripheral nervous system in Crohn disease]

In medical literature peripheral neurological disorders are associated with Crohn's disease only in particular cases. We report on two patients who suffering from Crohn's disease developed an acute Guillain-Barré syndrome or a polyneuropathy associated with myositis. Two weeks after a 65-year old female patient developed a serious Guillain-Barré syndrome, a haemorrhagical Crohn's colitis was diagnosed. Within a few weeks the specific therapy led to a satisfying recovery. A 45-year old female had suffered from Crohn's disease since 12 years. Within 8 weeks she developed a serious sensorimotor mixed axonal and demyelinating neuropathy and a granulomatous myositis. After treatment with steroids her signs constantly decreased. These observations as well as a literature review show that polyneuropathy and Guillain-Barré syndrome can be associated with chronic inflammatory bowel diseases. Our results suggest that peripheral neurological signs could be regarded as a possible extraintestinal manifestation of inflammatory bowel disease.

Intracranial stenoocclusive disease: double-detector helical CT angiography versus digital subtraction angiography

BACKGROUND AND PURPOSE

To our knowledge, no large-scale studies comparing the accuracy of CT angiography (CTA) to intraarterial digital subtraction angiography (DSA) of intracranial stenosis have been reported. We attempted to determine the diagnostic value of intracranial CT angiography (CTA) of normal vasculature and variants as well as of stenoocclusive disease.

METHODS

One-hundred and twelve patients underwent CTA and intraarterial angiography, and 2205 vascular segments were examined to ascertain presence, visibility, and degree of arterial stenoses (n = 105) as well as anatomic variants. Source, maximum intensity projection (MIP), and MIP-generated multiplanar reformatted (MPR) images were evaluated.

RESULTS

All 55 anatomic variants were identified correctly. Visibility of small-vessel segments was increased from 75% to 83% by using source images. MPR was helpful in differentiating distal vertebral hypoplasia from stenosis and in overcoming artifacts. All 43 occlusive segments were graded correctly (sensitivity = 100%, predictive value = 93.4%) as follows: severely stenotic ([n = 23], sensitivity = 78%, predictive value = 81.8%); moderately stenotic ([n = 36], sensitivity = 61%, predictive value = 84.6%); and mildly stenotic ([n = 3], sensitivity = 66%, predictive value = 28%). Normal segments (n = 2100) had a sensitivity of 99.5%, and CTA evinced a specificity of 99% for detecting stenoocclusive disease. Approximately one-third of wrong assessments were related to the petrous segment of the carotid artery.

CONCLUSION

CTA with double-detector technology and advanced postprocessing algorithms, including MPR, is about as reliable as MRA in depicting the vasculature of the anterior and posterior circulation and in grading intracranial stenoocclusive lesions, with the exception of the petrous segment of the carotid artery. CTA might be superior to MRA in the evaluation of poststenotic low-flow segments.

Phenotypic variability of the DYT1 mutation in German dystonia patients

Primary dystonia is a clinically and genetically heterogeneous movement disorder characterized by sustained involuntary muscle contractions causing repetitive movements and/or abnormal postures. Recently, the gene locus (DYT1) and mutation responsible for a substantial number of cases suffering from early-onset primary dystonia was described. Here we report 2 German families and 1 sporadic patient with early-onset dystonia due to the DYT1 mutation in order to illustrate the variability of clinical manifestation within this molecularly defined entity. We demonstrate that writer's cramp or focal cervical dystonia is a clinical presentation of DYT1 as well as generalized dystonia.

Evidence for a non-orthostatic origin of orthostatic tremor

OBJECTIVES

Orthostatic tremor was first described by Heilman in 1984. It usually occurs in the legs during stance and decreases markedly during sitting or walking. The aim of this study was to determine if orthostatic tremor is invariably associated with the orthostatic and weight bearing conditions in the arms and legs, and to investigate the features of orthostatic tremor under different levels of peripheral loading.

METHODS

Multichannel surface EMG recordings were obtained under different conditions (body posture and peripheral loading) from the proximal arm and leg muscles of seven patients fulfilling the clinical and electrophysiological criteria of orthostatic tremor.

RESULTS

In weight bearing positions (stance; weight bearing on the hands on all fours), all patients showed 13 Hz-16 Hz tremor activity, predominantly in the active limb. No tremor activity could be found in a supine position with muscles at rest. Isometric contraction of the limbs in the supine position led to synchronous 13 Hz-16 Hz rhythmic activity in five patients. No tremor was seen when the subjects were suspended in a harness with relaxed legs. Isometric contraction of the legs in this position produced tremor in two patients. A stepwise reduction of the body weight by a harness reduced the tremor activity. Additional loading (10 kg-20 kg) during stance led to an increase in tremor amplitude, but tremor frequency remained unchanged.

CONCLUSIONS

Orthostatic tremor is invariably present during stance or other weight bearing positions. It is not, however, always associated with orthostasis. In at least some patients it can be classified as an orthostasis independent action tremor. The failure of peripheral loading to modify tremor frequency indicates that orthostatic tremor may have a central, rather than a peripheral, origin.

[Calcinosis of the basal ganglia and hypoparathyroidism]

In most patients with basal ganglia calcification no disturbance of calcium metabolism is present. We present four patients with basal ganglia calcification. Two suffered from a secondary hypoparathyroidism following a complicated strumectomy years ago, one had an Alport-Syndrome and hypoparathyroidism. Her mother showed basal ganglia calcification and an abortive Alport-Syndrome as well, but no hypoparathyroidism.

[Bickerstaff encephalitis. Clinical and magnetic resonance follow-up studies]

We present a patient with Bickerstaff's brainstem encephalitis in whom MR imaging correlated with the clinical findings during the course of the disease. T2-weighted MR imaging showed increased signal intensity in the medulla oblongata, upper pons, pendunculi cerebelli and the cerebellum. In the course of the disease the lesions on MRI tended to descend more caudally. No anti-GQ1b antibody titers could be detected in the acute phase of the illness. Our findings suggest that MRI is the most valuable diagnostic tool in supporting the clinical diagnosis of Bickerstaff's brainstem encephalitis and may be helpful in the distinction between Miller Fisher syndrome and Bickerstaff's brainstem encephalitis.

Safety, pharmacokinetics and biological activity of enlimomab (anti-ICAM-1 antibody): an open-label, dose escalation study in patients hospitalized for acute stroke

BACKGROUND AND PURPOSE

To obtain information on the safety, pharmacokinetics and biological activity of enlimomab (anti-ICAM-1 antibody) in stroke patients.

METHODS

An open, uncontrolled, dose titration study was conducted in 32 patients hospitalized for stroke. Patients received one of four fixed dose regimens of enlimomab. A loading dose of enlimomab administered within 24 h of the onset of stroke symptoms was followed by four daily maintenance doses; total doses ranged from 140 to 480 mg.

RESULTS

The pharmacokinetic target levels (enlimomab serum levels of >/=10 microg/ml) were consistently achieved in all patients receiving dose regimens III and IV. Non-serious adverse events thought to be causally related to enlimomab administration included headache, vomiting and extrasystoles. Serious events occurred in 14 patients, including pneumonia, sepsis, cardiac failure and cardiac arrest. The only serious adverse event considered to be related to enlimomab administration was an anaphylactoid reaction, in a patient who received an unfiltered loading dose of antibody; the patient recovered. The overall mortality in the study was 15.6% and the 30-day mortality was 12.5%. There was no increase in the frequency of adverse events with increasing doses of enlimomab.

CONCLUSIONS

Doses of enlimomab between 140 and 480 mg administered over 5 days did not increase the risk of adverse events in patients with ischaemic or haemorrhagic stroke during an observation period of 30 +/- 10 days. A loading dose of 160 mg followed by four daily maintenance doses of 40 mg appears to be suitable for further study.

Botulinum toxin treatment of synkinesia and hyperlacrimation after facial palsy

OBJECTIVES

To investigate the effects of injection of botulinum toxin type A (BTX A) into the orbicularis oculi muscle and lacrimal gland in patients with aberrant regeneration after facial palsy (facial synkinesias and hyperlacrimation).

METHODS

The effect of the toxin injection (on average 75 mouse units of BTX A) into the orbicularis oculi muscle on facial synkinesias was assessed on a five point (0 to 4) scale in 10 patients with aberrant regeneration of facial nerve fibres after a peripheral facial nerve palsy. Six patients underwent a videographic control, which was assessed by a blinded independent investigator. In two patients with hyperlacrimation an extra dose of botulinum toxin (on average 20 mouse units BTX A) was injected into the lacrimal gland and the effect was assessed using the Schirmer test and on a three point scale.

RESULTS

Botulinum toxin type A had a good to excellent (grades 3 and 4) effect over an average of six months after 91% of injections. In 9% the injections had a moderate (grade 2) effect. Patients with hyperlacrimation showed a nearly complete recovery. There were no systemic side effects but focal side effects due to a temporary weakness of the orbicularis oculi muscle were not uncommon.

CONCLUSIONS

Botulinum toxin type A is the treatment of choice in motor and autonomic effects of aberrant regeneration of facial nerve after a peripheral palsy. The required dose is similar to or slightly lower than the dose usually recommended for hemifacial spasm.

Voluntary eyelid contraction modifies the blink reflex recovery cycle

In order to determine the extent to which the recovery cycle of the blink reflex is modified by voluntary contraction of the eyelids we investigated the electrically elicited blink reflex with paired stimuli of identical intensity in 9 healthy subjects. We pseudorandomly administered two interstimulus intervals (150 ms and 250 ms) in three different conditions of voluntary contraction of the orbicularis oculi muscle (relaxed, mild lid closure and strong lid closure). Our results show that inhibition of the R2 response following the second stimulus is significantly reduced with voluntary contraction. In addition, we found significantly larger amplitudes and shorter latencies of R1 and R2 with voluntary contraction. We conclude that in healthy subjects, voluntary eyelid contraction causes facilitation or disinhibition not only in the nuclei of the seventh cranial nerve, but also in the polysynaptic pathway of the R2. The possible implications on the interpretation of clinical data are discussed.

Cortical representation of proximal and distal arm muscles as assessed by focal transcranial magnetic stimulation

In 21 healthy volunteers, a mapping of cortical areas from which motor evoked potentials in deltoid muscle and first dorsal interosseal muscle (FDI) could be elicited by focal transcranial magnetic stimulation was performed. For this purpose, magnetic stimuli were applied using a figure-of-eight shaped magnetic coil and a Magstim 200 stimulator at an intensity of 15% above motor threshold for the deltoid muscle. There was a considerable overlap between the cortical areas from which motor responses of the two muscles could be evoked with the FDI represented more laterally than the deltoid muscle. The cortical location from which maximal amplitudes of motor evoked potentials were elicited was 4-8 cm lateral of Cz with the FDI and 2-6 cm lateral of Cz with the deltoid muscle. Calculated centres of cortical points with maximal muscle responses were significantly separated with the FDI represented 5.7 cm lateral of Cz and deltoid muscle 4.3 cm lateral of Cz. The anterior-posterior extension of the cortical maps did not show significant differences between the proximal and distal arm muscle. In no subject an ipsilateral representation of either muscle could be found even when stimulating at maximal intensity.

Transcranial magnetic double stimulation: influence of the intensity of the conditioning stimulus

The influence of stimulus parameters on compound muscle potentials evoked by transcranial magnetic double stimulation was systematically investigated. Two magnetic stimulators were discharged via a figure-of-eight-shaped magnetic coil (outer diameter of each circular coil, 7 cm) over the left hemisphere, 6 cm lateral to Cz, using a Bistim interface. Recordings were made from the right first dorsal interosseus muscle. In experiment I, in 12 healthy volunteers the intensity of the conditioning subthreshold stimulus was varied from 0 to 100% of the relaxed motor threshold at an interstimulus interval of 1 ms. In experiment II, interstimulus intervals of 1, 3 and 5 ms were used to investigate the effect of conditioning stimuli of 3 fixed intensities. Maximal reduction of the amplitude of motor evoked potentials was found at a conditioning stimulus intensity of 65% of the relaxed motor threshold (and at an interstimulus interval of 1 ms). Because intensities of the conditioning stimulus higher than 65% reduced amplitudes of motor evoked potentials less effectively than at this intensity, refractoriness of pyramidal neurons can be ruled out as the main mechanism contributing to the observed inhibition. Activation of inhibitory interneurons by intensities lower than is necessary to activate pyramidal neurons is discussed as a possible mechanism for the inhibitory effects evoked by transcranial magnetic stimulation.

Transcallosal inhibition in cortical and subcortical cerebral vascular lesions

The excitability of the motor cortex after transcranial magnetic stimulation was investigated in 10 patients with purely subcortical, and in 22 patients with cortical-subcortical cerebrovascular lesions. In the first investigation we applied magnetic double stimuli over both motor cortices with different inter-stimulus intervals. The first (conditioning) stimulus was applied to the affected hemisphere and the second stimulus (test stimulus) to the unaffected side. The responses of the first dorsal interosseal (FDI) muscle, contralateral to the test stimulus, were recorded after applying the test stimulus alone and at inter-stimulus intervals of 5 ms, 7 ms, 15 ms, 30 ms and 60 ms. In a second investigation the patients were asked to activate their non-paretic first dorsal interosseus muscle and the magnetic stimulus was applied over the affected hemisphere. The EMG responses were rectified and averaged. Patients with subcortical cerebral lesions below the centrum semiovale (i.e., having no effect on the transcallosal fibres) displayed a pronounced inhibition of one motor cortex after the stimulation of the contralateral side, comparable with normal subjects. Patients with cortical-subcortical cerebral lesions displayed only partly less inhibition of their motor cortex but the results in this group were not uniform. Since inhibition was preserved in patients with subcortical lesions, which had destroyed the corticospinal tract, we conclude that this inhibition is not mediated through an ipsilateral projection but via a transcallosal route.

[Periodic paralysis as the first manifestation of hyperthyroidism]

HISTORY AND CLINICAL FINDINGS

A 19-year-old man had mild diarrhoea at the time that suddenly one night he was unable to turn in his bed and the following morning could not move his arms and legs for 4 hours. Neither he nor any family members had previously had any paralysis. Physical examination was unremarkable except for mild tachycardia and first-degree goitre.

INVESTIGATIONS

A provocation test with glucose (3 g/kg) and insulin (0.1 IU/kg) caused renewed paralysis for several hours, serum potassium falling from 4.3 to 3.4 mmol/l. The paralysis was reversed on oral potassium (40 mmol) Thyroid function tests revealed hyperthyroidism with an increased concentration of free thyroxine (25.5 pg/ml) and free triiodothyronine (9.7 pg/ml), while thyroid-stimulating hormone was decreased (0.07 mU/I), supporting the diagnosis of autoimmune thyroiditis.

TREATMENT AND COURSE

Thyrostatic treatment was started with thiamazole (10 mg every other day). There was no further periodic paralysis and another provocation test was negative.

CONCLUSION

Fleeting paralysis is often misdiagnosed as being psychogenic. Potassium abnormalities are the most common cause but are only rarely associated with hyperthyroidism. This case of thyrotoxic hypokalaemic paralysis was probably based on a genetic defect of muscle fibre membrane manifesting itself only in the presence of hyperthyroidism.

Effects of carbamazepine on cortical excitatory and inhibitory phenomena: a study with paired transcranial magnetic stimulation

The effect of a single dose of oral carbamazepine on cortical facilitatory and inhibitory phenomena was investigated in 13 healthy human subjects by focal transcranial magnetic stimulation. Paired stimulation was performed via a figure-of-eight shaped magnetic coil using two Magstim-200 stimulators and a Bistim-interface at interstimulus intervals of 3, 10, and 17 ms. In addition, the silent period evoked by single focal transcranial stimuli during sustained voluntary muscle contraction was investigated without and with carbamazepine. Recordings of compound muscle action potentials (CMAP) were taken from the left first dorsal interosseus muscle. Carbamazepine significantly reduced the facilitatory effect of conditioning stimuli of 85% of motor threshold at an interstimulus interval of 10 ms on the CMAP-amplitude from 162% to 127%, whereas under all other conditions no significant depression of CMAP-amplitudes occurred. This effect is discussed in the context of carbamazepine's use-dependent inhibition of neuronal high-frequency discharges. The mean relative duration of the silent period was longer with carbamazepine at all 6 stimulus intensities investigated, the absolute effect being very low in relation to the interindividual variability of silent period duration. The study demonstrates the applicability of transcranial magnetic stimulation as an in vivo method in the assessment of drug effects on cortical facilitatory as well as inhibitory phenomena.

[Follow-up and immunologic findings in drug-induced myasthenia]

PATIENT AND METHOD

We report 5 patients, who developed myasthenia, four of them after treatment on D-penicillamine, one after treatment on chloroquine. 3 patients suffered from rheumatoid arthritis, one from a psoriatic arthritis and one from cirrhosis of the liver. Three patients developed an ocular myasthenia, one patient an oculopharyngeal and one patient has had generalized myasthenic syndrome.

RESULTS

Four patients showed an improvement of clinical status within days up to 18 months following discontinuation of the therapy, whereas one patient deteriorated. The quickest improvement was observed in the patient with chloroquine induced myasthenia. Four patients had raised acetylcholine-receptor antibody titers. The patient with chloroquine induced myasthenia had had a normal acetylcholin-receptor antibody titer. The human leucocyte antigen type was compared with the results of literature.

CONCLUSION

To what extent human leucocyte antigen type HLA DR 4 has a correlation with the development of myasthenia following treatment on chloroquine can not yet be answered with respect to the very small number of cases at the moment.

Botulinum toxin in the therapy of gustatory sweating

Three patients suffering from gustatory sweating following trauma to the preauricular region from a bullet wound or parotid gland surgery were treated by intracutaneous injection of botulinum toxin A. Within 2 weeks, gustatory sweating in the area injected completely ceased in all patients with no side-effects. The efficacy of treatment was confirmed by repeated Minor's iodine starch tests. So far, sweating has not recurred during a follow-up period of up to 8 months. Botulinum toxin appears to be a promising new drug for the treatment of this autonomic disorder.

Pure stimulus-sensitive truncal myoclonus of propriospinal origin

The clinical and electrophysiological features of stimulus-sensitive truncal myoclonus are described in a 49-year-old woman. Touching the skin of the back and abdomen would evoke jerks in both ipsilateral and contralateral axial muscles; there was no spontaneous jerking. Multichannel EMG recordings showed bilateral short-latency muscle bursts at truncal recording sites both rostral and caudal to stimulus sites. The short latencies of muscle bursts in adjacent segments give evidence of a spinal origin of myoclonus; the pattern of recruitment and the velocity of spread suggest the involvement of propriospinal pathways. The presence of intrathecal IgG synthesis and of oligoclonal bands in the CSF point towards an inflammatory process which may underly the unusual type of myoclonus in this patient.

A unique case of tardive dystonia induced by short-term therapy with perazin

Perazin is a piperazine derivative of phenothiazine with higher affinity for the D2 than the D1 receptor. We observed a 43-year-old woman who developed blepharospasm and oral hyperkinesia as a tardive dystonic syndrome after short-term treatment with perazin. She had never taken any other neuroleptic medication and all known forms of secondary dystonia were ruled out. We were unable to find any previous reports of perazin-induced tardive dystonia.

Hemispheric asymmetries of early cortical somatosensory evoked potentials revealed by topographic analysis

Scalp topography of the early cortical SEPs was analysed in 50 normal right handed subjects. The following hemispheric asymmetries of the potentials were found: 1) The maximal amplitude of N20 was located predominantly at the P electrode after right sided stimulation, but varied between the CP, P and O electrode after left sided stimulation. 2) The N20 amplitudes were higher after right sided stimulation in approximately 70% of the subjects and the P25 and N30 amplitudes were higher after left sided stimulation in again approximately 70% of the subjects. No side difference of amplitudes was found for the subcortical N14. The N20 amplitude and location asymmetries were attributed to an anatomical asymmetry of the somatosensory cortex.

Cervical dystonia as an isolated sign of a basal ganglia tumour

Images

[Severe "late" dystonia after neuroleptic anxiolysis with fluspirilene]

The development of severe tardive dystonia after short-term use of low-dose Fluspirilen is described. A 39-year-old woman was treated with Fluspirilen IM by her family doctor for reactive depression. She did received no other neuroleptic agents and no risk factors for the development of tardive dyskinesia (e.g. old age or organic brain damage) were present. For the first time a relation between short-term monotherapy with Fluspirilen and tardive dyskinesia appears highly probable. The use of Fluspirilen for the treatment of psychogenic disturbances should therefore be considered carefully.

Blink reflex in patients with an ischaemic lesion of the brain-stem verified by MRI

The electrically elicited blink reflex was investigated in 25 patients with ischaemic lesions of the pons or the medulla oblongata. Only patients with a lesion on MRI appropriate to the clinical syndrome were included. Twenty patients had an infarction of the pons, bilateral in 5. Additional 5 patients had an infarction of the dorsolateral medulla oblongata. Patients with hemispheric lesions were excluded. Four of the 5 patients with Wallenberg's syndrome showed delayed R2 components to stimulation ipsilateral to the lesion. Additional loss of the ipsilateral R1 component was observed in 1 patient. Fifteen of the 20 patients with pontine infarctions had pathological blink reflexes. All 6 patients with a unilateral pons lesion and an abnormality of R1 had this abnormality on the side contralateral to the lesion. In 3 cases with bilateral pontine infarction R1 was abnormal on one side or on either side. Of 11 patients with a normal R1, 6 had isolated abnormalities of R2 without consistent correlation to the side of the lesion. We conclude that abnormalities of the blink reflex are of minor localizing value in pontine infarction. This may be explained by the fact that a pontine infarction affects either the reflex arch itself or descending pathways that have a modulating influence on the reflex arch. Infarctions of the medulla oblongata, however, have characteristic abnormalities that have already been described.

Corticocortical inhibition in human motor cortex

1. In ten normal volunteers, a transcranial magnetic or electric stimulus that was subthreshold for evoking an EMG response in relaxed muscles was used to condition responses evoked by a later, suprathreshold magnetic or electric test shock. In most experiments the test stimulus was given to the lateral part of the motor strip in order to evoke EMG responses in the first dorsal interosseous muscle (FDI). 2. A magnetic conditioning stimulus over the hand area of cortex could suppress responses produced in the relaxed FDI by a suprathreshold magnetic test stimulus at interstimulus intervals of 1-6 ms. At interstimulus intervals of 10 and 15 ms, the test response was facilitated. 3. Using a focal magnetic stimulus we explored the effects of moving the conditioning stimulus to different scalp locations while maintaining the magnetic test coil at one site. If the conditioning coil was moved anterior or posterior to the motor strip there was less suppression of test responses in the FDI. In contrast, stimulation at the vertex could suppress FDI responses by an amount comparable to that seen with stimulation over the hand area. With the positions of the two coils reversed, conditioning stimuli over the hand area suppressed responses evoked in leg muscles by vertex test shocks. 4. The intensity of both conditioning and test shocks influenced the amount of suppression. Small test responses were more readily suppressed than large responses. The best suppression was seen with small conditioning stimuli (0.7-0.9 times motor threshold in relaxed muscle); increasing the intensity to motor threshold or above resulted in less suppression or even facilitation. 5. Two experiments suggested that the suppression was produced by an action on cortical, rather than spinal excitability. First, a magnetic conditioning stimulus over the hand area failed to produce any suppression of responses evoked in active hand muscles by a small (approximately 200 V, 50 microsecond time constant) anodal electric test shock. Second, a vertex conditioning shock had no effect on forearm flexor H reflexes even though responses in the same muscles produced by magnetic cortical test shocks were readily suppressed at appropriate interstimulus intervals. 6. Small anodal electric conditioning stimuli were much less effective in suppressing magnetic test responses than either magnetic or cathodal electric conditioning shocks.(ABSTRACT TRUNCATED AT 400 WORDS)

[Clinical course of paraneoplastic limbic encephalitis]

A 49-year-old woman presented with increasing memory loss without dementia. The EEG showed slow activity over the temporal lobe. MRT revealed temporal areas of increased signal intensity without gadolinium enhancement. The diagnosis of limbic encephalitis was made after detection of a bronchial carcinoma. A MRT control examination after chemotherapy showed resolution of the abnormalities. This observation may indicate that chemotherapy has modified that part of the immunological system responsible for induction of limbic encephalitis.

Simulation of the conduction velocity properties of nerve fibres by an electrical model

The paper presents a simple electrical circuit model from which the relationship between the diameter of the axon and its conduction velocity can be derived. The model is primarily intended for the larger myelinated fibres in peripheral nerves. However, a simplified model is also shown for nonmyelinated fibres, where the relationship is quite different. In the conclusion some qualitative considerations are presented for thin myelinated fibres with a slow velocity of conduction. The conduction velocity/diameter relationship of these fibres gradually approaches that for nonmyelinated fibres with decreasing diameter.

Tremor due to stroke

We report on four patients with unilateral tremor stemming from cerebrovascular accidents. In two patients with proven lesions of the thalamus, the tremor was irregular and, in addition, there was dystonic posturing of the affected arm. Tremor and dystonic posturing had appeared after the stroke. In the other two patients tremor had occurred immediately at the onset of the stroke and lasted only a few days. The tremors were of small amplitude and high frequency, and lesions could not be found on CT or MRI in these two patients. None of our patients showed signs of the so-called rubral tremor.

[Topography of early cortical median nerve somatosensory evoked potentials: results for routine use of the method]

The results from a topographic analysis of the early median nerve SEPs allowed to design a method for recording and analysing the SEPs in the routine laboratory. The detailed analysis of the topography of 50 normal subjects revealed: 1. An inter- and intraindividual variability of the location of the maximal amplitudes, 2. A significantly longer latency of the cortical potentials after left side stimulation, 3. A significantly higher amplitude of N20 after left side stimulation and 4. A significantly higher amplitude of the later potentials P25 and N30 after right side stimulation. It was shown that a 4-channel recording from the neck at C7 with a Fz-reference as well as from stimulus contralateral F3, CP3 and P3 or F4, CP4 and P4 with an stimulus contralateral earlobe reference provides all necessary parameters in comparison to an 20-channel recording. The definition of normal values has to take into account these results. Absolute maximum values were taken instead of the standard deviation because all amplitude values were proven to be not distributed normally. In 7 out of 30 MCA-stroke patients pathological SEP amplitudes were obtained using the 4-channel montage, whereas the 1-channel recording from CP3 and CP4 with a Fz-reference revealed normal amplitudes.

Cortical projection to erector spinae muscles in man as assessed by focal transcranial magnetic stimulation

We stimulated the motor cortex in 9 subjects using focal transcranial magnetic stimulation with a figure of 8 coil in order to examine the cortical representation of the erector spinae muscles. Recordings were made from the erector spinae 3.5 cm lateral to the third lumbar vertebra. In 5 subjects clearly reproducible responses could be obtained which had a latency compatible with transmission via fast conducting fibers in a mono- or oligosynaptic pathway. In the remaining 4 subjects responses were poorly defined. Latencies in surface recordings varied between 13 and 24 msec but were longer when needle recordings were used. Mapping of the motor cortex was performed by moving the coil in 2 cm steps on either side of Cz. Different patterns of hemispheric representation were found ranging from a contralateral projection in either hemisphere to a representation of both back muscles in one hemisphere (2 subjects). Responses were followed by a silent period. The latter was interrupted or terminated by a response between 52 and 85 msec post stimulus which was found predominantly in the muscle ipsilateral to the side of stimulation.

[Damage to the lateral cutaneous femoral nerve after transfemoral angiography]

We report on two patients with lesions of the lateral cutaneous nerve of the thigh after transfemoral angiography. Symptoms were hypesthesia, dysesthesia and hypalgesia of the right lateral thigh. One patient had no hematoma, the other a hematoma of the medial thigh which did not enlarge thigh circumference. Both patients had had a tight pressure bandage applied for 24 hours. There were no signs of a femoral nerve lesion. Both patients were severely distressed by paresthesia. The numbness subsided after three weeks in one patient, but pain persisted. The other patient had symptoms for over six months. The lateral cutaneous nerve of the thigh is located distinctly lateral to the puncture site in transfemoral angiography. Hence we suggest that the nerve lesion was caused neither by the puncture itself nor by a hemorrhage, but by the tight bandage.

Recombinant tissue plasminogen activator in acute thrombotic and embolic stroke

An open angiography-based, dose rate escalation study on the effect of intravenous infusion of recombinant tissue plasminogen activator (rt-PA) on cerebral arterial recanalization in patients with acute focal cerebral ischemia was performed at 16 centers. Arterial occlusions consistent with acute ischemia in the carotid or vertebrobasilar territory in the absence of detectable intracerebral hemorrhage were prerequisites for treatment. After the 60-minute rt-PA infusion, arterial perfusion was assessed by repeat angiography and computed tomography scans were performed at 24 hours to assess hemorrhagic transformation. Of 139 patients with symptoms of focal ischemia, 80.6% (112) had complete occlusion of the primary vessel at a mean of 5.4 +/- 1.7 hours after symptom onset. No dose rate response of cerebral arterial recanalization was observed in 93 patients who completed the rt-PA infusion. Middle cerebral artery division (M2) and branch (M3) occlusions were more likely to undergo recanalization by 60 minutes than were internal carotid artery occlusions. Hemorrhagic infarction occurred in 20.2% and parenchymatous hematoma in 10.6% of patients over all dose rates, while neurological worsening accompanied hemorrhagic transformation (hemorrhagic infarction and parenchymatous hematoma) in 9.6% of patients. All findings were within prospective safety guidelines. No dose rate correlation with hemorrhagic infarction, parenchymatous hematoma, or both was seen. Hemorrhagic transformation occurred significantly more frequently in patients receiving treatment at least 6 hours after symptom onset. No relationship between hemorrhagic transformation and recanalization was observed. This study indicates that site of occlusion, time to recanalization, and time to treatment are important variables in acute stroke intervention with this agent.

[Spatial distribution of the action potentials of the sural nerve]

We investigated the spatial distribution of the sural nerve sensory nerve action potential (SNAP) in 25 healthy subjects between 21 and 50 years. Stimulation was achieved through surface electrodes at the lateral malleolus. Recordings were made 15-18 cm proximal to the site of the stimulation from different positions on a line perpendicular to the sural nerve using needle electrodes insulated except for the tip. The amplitude of the SNAP decreased on both sides of the potential of highest amplitude. 10 mm lateral to the potential of highest amplitude the mean amplitude was reduced to 55%. The latency of the first positive phase decreased within increasing distance from the largest SNAP. We explained this with different influence of more distal, earlier depolarized nerve segments on the locally generated SNAP. In 20 subjects we performed an additional recording using an uninsulated needle electrode that was placed 3-4 cm subcutaneously perpendicular to the sural nerve. The latency of the SNAP recorded in this way was similar to the latency of the largest SNAP using the insulated needle electrode; however, the amplitude was smaller by 19%. We recommend for clinical practice to use the uninsulated needle in case the SNAP is smaller than 4 microV.

High frequency vibration induced gating of subcortical and cortical median nerve somatosensory evoked potentials: different effects on the cervical N13 and on the P13 and P14 far-field SEP components

Subcortical and cortical somatosensory evoked potentials (SEP) to median nerve stimulation were recorded before, during and after high frequency (270 Hz) vibration of the fingers 1-3 in 8 healthy subjects. A marked decrease of the amplitude of all potentials was observed. The attenuation of the sensory nerve action potential (SNAP) of the median nerve and the attenuation of SEP components N9, N11 and N13 showed no differences, while the attenuation of the subcortical P14 component was significantly higher. This is in accordance with a generator of the cervical N13 in the interneurons beside the lemniscal pathway. The cortical N20 (post-rolandic) was significantly more decreased in amplitude than P14 while P22 (pre-rolandic) remained reduced in amplitude like P14. An increased latency of the far-field subcortical P14 was observed, while P13 recorded in the same montage remained unchanged in latency. These findings suggest different generators of these peaks. A generator of P14 above the nucleus cuneatus is confirmed. A presynaptic generator of P13 is suspected.

German-Austrian Space Occupying Cerebellar Infarction Study (GASCIS): study design, methods, patient characteristics. The Steering and Protocol Commission

An open prospective multicentric therapeutic trial to determine the timing and type of therapeutic intervention in patients presenting with secondary deterioration following cerebellar stroke is described. According to the results of retrospective studies a controlled approach comparing different therapies is ethically not feasible. Participants use the same scores and protocol for patient data collection but many choose different therapeutic procedures.

Transcranial magnetic stimulation in pontine infarction: correlation to degree of paresis

Transcranial magnetic stimulation was performed in 20 patients with pontine infarction who had initially some degree of hemiparesis. Only patients with a well defined lesion on magnetic resonance imaging that was appropriate for the neurological signs were included. Recordings were made from the abductor pollicis brevis muscle (APB) bilaterally. The degree of hand paresis was estimated clinically and related to the following parameters: central motor conduction time (CMCT), interside latency difference of total latency, and amplitude ratio of affected to unaffected side. Increasing degree of paresis was associated with increasing latency parameters and decreasing amplitude ratio. In the four patients with severe paresis a low amplitude response could be evoked and CMCT was delayed by up to 10 ms. When the paresis had resolved at the time of transcranial magnetic stimulation CMCT was normal. However, amplitude ratio was less than 100% in all but one patient, with most of the values ranging between 40% and 60%, which indicates a subclinical pyramidal tract lesion. Median nerve sensory evoked potentials (SEP) and related interside latency difference to amplitude ratio N20/P25 were also recorded. In contrast to TCMS, decreased amplitude ratio of SEP was not associated with delayed latency. Clinically, the mild degree of and good recovery from paresis in ventral pontine infarction was remarkable.

Bilateral anterior cerebral artery territory infarction in the differential diagnosis of basilar artery occlusion

Two patients with bilateral anterior cerebral artery (ACA) territory infarction are presented whose initial diagnosis was basilar artery occlusion. Both had tetraparesis; in one it was asymmetrical. Both had their eyes open and did not respond to command except that after a delay they followed with their eyes a smoothly moving object; this was the only sign of awareness. One patient had a clear vertical gaze palsy in the upward and downward direction unaccompanied by pupillary abnormalities. Computed tomography revealed fresh bilateral ACA infarction in both patients; occlusion in the hind brain circulation was excluded by angiography in one. Both patients suffered from atrial fibrillation, so cardiac embolism was the most likely cause of the stroke. We conclude that bilateral ACA territory infarction should be considered in the differential diagnosis of basilar artery occlusion, even if accompanied by vertical gaze palsy.

[Excitability of the blink reflex during self-elicitation or elicitation by others]

Electrically evoked blink reflexes were studied in 24 healthy subjects in different conditions of elicitation. In one condition the electrical shock was delivered by the experimenter; in a second condition the subject triggered the stimulus himself by manually operating a switch. The different conditions were investigated relaxed or clenching the fist with left hand. Moreover, in 3 subjects the stimulus was given in various delays after the occurrence of the EMG activity of the forearm flexor muscles due to a ballistic wrist flexion. The latencies and peak to peak amplitudes of the ipsi- and contralateral early and late responses were analysed. Voluntary sustained contraction of the left hand (fist) caused no significant modification of the blink reflex. Self-triggering of the stimulus had a facilitating influence on the early components (R1, R1') and an inhibitory effect on the late components (R2, R2'). In EMG triggered self-stimulation the R2-inhibition could already be seen at a delay of 0 ms. From a delay of 10 ms on the suppression was still more pronounced and recovered over the following 500-1000 ms. We conclude, that the reflex alterations are not due to the outflow of the motor cortex, but to the conditioning effect of self-elicitation. The influence on the excitability of the blink reflex resemble that described in the literature for the conditioning effect of an acoustic or visual stimulus. We suggest involvement of the same interneuron network on the condition of self-eliciting.