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Motor skill learning is critical in post-stroke motor recovery, but little is known about its underlying neural substrates. Recently, using a new visuomotor skill learning paradigm involving a speed/accuracy trade-off in healthy individuals we identified three subpopulations based on their behavioral trajectories: fitters (in whom improvement in speed or accuracy coincided with deterioration in the other parameter), shifters (in whom speed and/or accuracy improved without degradation of the other parameter), and non-learners. We aimed to identify the neural substrates underlying the first stages of motor skill learning in chronic hemiparetic stroke patients and to determine whether specific neural substrates were recruited in shifters versus fitters. During functional magnetic resonance imaging (fMRI), 23 patients learned the visuomotor skill with their paretic upper limb. In the whole-group analysis, correlation between activation and motor skill learning was restricted to the dorsal prefrontal cortex of the damaged hemisphere (DLPFCdamh: r = -0.82) and the dorsal premotor cortex (PMddamh: r = 0.70); the correlations was much lesser (-0.16 < r > 0.25) in the other regions of interest. In a subgroup analysis, significant activation was restricted to bilateral posterior parietal cortices of the fitters and did not correlate with motor skill learning. Conversely, in shifters significant activation occurred in the primary sensorimotor cortexdamh and supplementary motor areadamh and in bilateral PMd where activation changes correlated significantly with motor skill learning (r = 0.91). Finally, resting-state activity acquired before learning showed a higher functional connectivity in the salience network of shifters compared with fitters (qFDR < 0.05). These data suggest a neuroplastic compensatory reorganization of brain activity underlying the first stages of motor skill learning with the paretic upper limb in chronic hemiparetic stroke patients, with a key role of bilateral PMd.

Motor skill learning is one of the key components of motor function recovery after stroke, especially recovery driven by neurorehabilitation. Transcranial direct current stimulation can enhance neurorehabilitation and motor skill learning in stroke patients. However, the neural mechanisms underlying the retention of stimulation-enhanced motor skill learning involving a paretic upper limb have not been resolved. These neural substrates were explored by means of functional magnetic resonance imaging. Nineteen chronic hemiparetic stroke patients participated in a double-blind, cross-over randomized, sham-controlled experiment with two series. Each series consisted of two sessions: (i) an intervention session during which dual transcranial direct current stimulation or sham was applied during motor skill learning with the paretic upper limb; and (ii) an imaging session 1 week later, during which the patients performed the learned motor skill. The motor skill learning task, called the 'circuit game', involves a speed/accuracy trade-off and consists of moving a pointer controlled by a computer mouse along a complex circuit as quickly and accurately as possible. Relative to the sham series, dual transcranial direct current stimulation applied bilaterally over the primary motor cortex during motor skill learning with the paretic upper limb resulted in (i) enhanced online motor skill learning; (ii) enhanced 1-week retention; and (iii) superior transfer of performance improvement to an untrained task. The 1-week retention's enhancement driven by the intervention was associated with a trend towards normalization of the brain activation pattern during performance of the learned motor skill relative to the sham series. A similar trend towards normalization relative to sham was observed during performance of a simple, untrained task without a speed/accuracy constraint, despite a lack of behavioural difference between the dual transcranial direct current stimulation and sham series. Finally, dual transcranial direct current stimulation applied during the first session enhanced continued learning with the paretic limb 1 week later, relative to the sham series. This lasting behavioural enhancement was associated with more efficient recruitment of the motor skill learning network, that is, focused activation on the motor-premotor areas in the damaged hemisphere, especially on the dorsal premotor cortex. Dual transcranial direct current stimulation applied during motor skill learning with a paretic upper limb resulted in prolonged shaping of brain activation, which supported behavioural enhancements in stroke patients., (© The Author (2014). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Background: After stroke, deregulated interhemispheric interactions influence residual paretic hand function. Anodal or cathodal transcranial direct current stimulation (tDCS) can rebalance these abnormal interhemispheric interactions and improve motor function., Objective: We explored whether dual-hemisphere tDCS (dual-tDCS) in participants with chronic stroke can improve fine hand motor function in 2 important aspects: precision grip and dexterity., Methods: In all, 19 chronic hemiparetic individuals with mild to moderate impairment participated in a double-blind, randomized trial. During 2 separate cross-over sessions (real/sham), they performed 10 precision grip movements with a manipulandum and the Purdue Pegboard Test (PPT) before, during, immediately after, and 20 minutes after dual-tDCS applied simultaneously over the ipsilesional (anodal) and contralateral (cathodal) primary motor cortices., Results: The precision grip performed with the paretic hand improved significantly 20 minutes after dual-tDCS, with reduction of the grip force/load force ratio by 7% and in the preloading phase duration by 18% when compared with sham. The dexterity of the paretic hand started improving during dual-tDCS and culminated 20 minutes after the end of dual-tDCS (PPT score +38% vs +5% after sham). The maximal improvements in precision grip and dexterity were observed 20 minutes after dual-tDCS. These improvements correlated negatively with residual hand function quantified with ABILHAND., Conclusions: One bout of dual-tDCS improved the motor control of precision grip and digital dexterity beyond the time of stimulation. These results suggest that dual-tDCS should be tested in longer protocols for neurorehabilitation and with moderate to severely impaired patients. The precise timing of stimulation after stroke onset and associated training should be defined.

Background/introduction: Motor learning plays a central role in daily life and in neurorehabilitation. Several forms of motor learning have been described, among which motor skill learning, i.e. reaching a superior level of performance (a skill) through a shift of the speed/accuracy trade-off. During the first stage of learning a visuomotor skill, we observed differential patterns of evolution of the speed/accuracy trade-off in normal subjects. Half of the subjects rapidly achieved successful motor skill learning with an early shift of the speed/accuracy trade-off leading to a superior level of performance (shift pattern). The other subjects attained only minimal global improvement due to a converse evolution of speed and accuracy (i.e. a respect of the speed/accuracy trade-off: fit pattern). Functional magnetic resonance imaging (fMRI) was used to explore the neural substrates underlying these differential patterns during the first stage of motor skill learning in normal subjects., Methods: Twenty right-handed normal subjects performed an implicit visuomotor learning task with their non-dominant hand. The task ("circuit game") consisted in learning to navigate a pointer along a circuit as quickly and accurately as possible using a fMRI-compatible mouse. Velocity, accuracy, and performance indexes were used to characterise the motor learning pattern (shift/fit) and to perform fMRI correlation analysis in order to find the neural substrate associated with the shift and fit patterns during early motor skill learning., Results: Nine subjects showed a fit pattern (fitters), and eleven, a shift pattern ("shifters"). fMRI analyses at whole group level (ANOVA) and at sub-group level demonstrated that the supplementary motor area (SMA) was more activated in "shifters" than in the "fitters" groups and that the BOLD activation within the SMA correlated significantly with the on-line shift of the speed/accuracy trade-off in the "shifters" group., Conclusion: Despite identical instructions and experimental conditions, during the first stage of motor skill learning normal subjects spontaneously adopted different patterns that can be differentiated based on distinct fMRI activation patterns. In this implicit visuomotor task, the SMA proper was the key area underlying the achievement of early successful motor skill learning, i.e. on-line shift of the speed/accuracy trade-off., (Copyright © 2012 Elsevier Inc. All rights reserved.)

The profile of recurrent ischemic strokes has not been much investigated. The aim of this study was to evaluate how the therapeutic strategies recommended for secondary prevention after an ischemic stroke are implemented in the real world of clinical practice. All patients admitted for a recurrent ischemic stroke or TIA were prospectively registered. The etiology was determined according to the TOAST classification. The risk factors and cardiovascular treatment at the time of the recurrence were recorded. A total of 168 patients were evaluated. Most of the patients (61%) recurred after 1 year. The recurrent stroke was not associated with a particular etiological subtype. The most frequent risk factor was hypertension (79%), followed by hypercholesterolemia (43%), smoking (25%), and diabetes (22%). Most of the patients had more than 1 risk factor (84%). Hypertension was not satisfactorily controlled in 38% of patients, hypercholesterolemia in 42%, and diabetes in 59%. A significant minority of patients (15%) were not taking any antithrombotic agent despite a history of stroke or TIA. Only 34% of the cases with a known atrial fibrillation were on anticoagulant therapy and the International Normalized Ratio was < 2.0 in 71% of them. In conclusion, stroke prevention needs to be improved by better implementation of therapeutic strategies in clinical practice. The patients should also be better informed about target values as well as the importance of physical activity and smoking cessation.

Purpose: We report the Belgian results of the Safe Implementation of Thrombolysis in Stroke - International Stroke Thrombolysis Register (SITS-ISTR). This prospective observational register evaluates the safety and efficacy of intravenous thrombolysis with rtPA (recombinant tissue Plasminogen Activator) for ischemic stroke in routine clinical practice., Methods: We compared the baseline characteristics, treatment delay, rate of symptomatic intracerebral hemorrhage and functional outcome at 90 days after treatment between patients enrolled in centres in Belgium and the non-Belgian SITS-registry population. We performed a multivariate analysis to adjust for differences in demographic and baseline characteristics., Results: 743 patients were enrolled in 42 centers in Belgium between December 2002 and December 2007. These patients were older, had more severe stroke were more frequently female and more frequently had hyperlipidemia and atrial fibrillation. The median stroke onset-to-treatment delay was 140 min vs. 145 min. More patients died and were disabled 3 months after the stroke. A slight, non-significant, increase of symptomatic intracerebral hemorrhage (SICH) as per SITS protocol was observed (2.4 vs. 1.6%, p = 0.15). After adjustment for differences in baseline characteristics, functional independence (mRS < or = 2) at 3 months (OR 0.95, 95% CI 0.86-1.05, p = 0.31) was not different from non-Belgian patients, nor was the rate of SICH. However mortality at 3 months in Belgian patients was slightly higher (OR 1.15, 95% CI 1.02-1.29, p = 0.02)., Conclusion: Intravenous thrombolysis for ischemic stroke is safe and effective in the routine clinical use in Belgium. The higher mortality we observed is not related to a higher rate of SICH.

There is ample evidence from randomized trials that for patients with stroke, stroke unit care is superior to care in general medical or neurological wards. This evidence, which has been adopted by international guidelines has to be implemented into daily stroke care. This consensus document prepared by the Belgian Stroke Council provides a set of minimum criteria to meet international standards for stroke care. It is intended to provide help in the creation of stroke units in centers who do not currently have one and to provide a benchmark for centres already having organised stroke care.

Recent registry results have shown that polyvascular disease (PolyVD), usually manifested as coronary heart disease or peripheral arterial disease (PAD), is a marker of increased morbidity and mortality in patients with noncardioembolic ischaemic stroke, but is often inadequately assessed. This Personal View Paper advocates routine examination for PolyVD in such patients. Peripheral arterial disease can be readily detected in routine practice by measurement of the ankle-brachial index. This paper makes recommendations for risk stratification, discharge documentation and, where possible, management of ischaemic stroke patients with PolyVD.

The apolipoprotein E (APOE) epsilon4 allele is associated with elevated cholesterol and risk of atherosclerosis. However, its role in ischemic stroke (IS) remains controversial. We investigated a possible link between IS or the severity of intracranial atherosclerosis and the APOE promoter polymorphisms -219G/T and +113G/C, involved in regulating APOE transcription. We genotyped subjects from a multicentric Belgian case-control study, including 237 middle-aged patients with IS due to small- or large-vessel atherosclerotic stroke and 326 ethnicity- and gender-matched controls and a Finnish autopsy series of 1004 non-stroke cases, who had received a quantitative score of atherosclerosis in the circle of Willis. The APOE epsilon4+ genotype did not associate with IS, but was related to more severe intracranial atherosclerosis score in men (5.4 vs 4.6, P=0.044). Within the most common APOE epsilon3/epsilon3 genotype group, the risk of IS associated with the G-allele of the tightly linked -219G/T (OR=6.2; 95% CI: 1.6-24.3, P=0.009) and +113G/C (OR=7.1; 95% CI: 1.7-29.9, P=0.007) promoter polymorphisms. There was no difference in the severity of intracranial atherosclerosis between -219G/G genotype carriers and non-carriers. This study suggests a multifaceted role of apoE on the risk of cerebrovascular diseases. The APOE epsilon4+ genotype did not predict the risk of IS but was associated with severity of subclinical intracranial atherosclerosis in men on the autopsy study. In contrast, the promoter variants were significant predictors of IS, suggesting that quantitative rather than qualitative variation of apoE is related to IS.

Background and Aims: The short time window is frequently cited as the main reason for exclusion of intravenous tissue plasminogen activator (tPA) in acute stroke. Identifying and circumventing barriers to thrombolysis other than time could increase the frequency of treatment. The goal of this study was to identify whether the rate of treatment with tPA would increase if time window was not an obstacle to treatment., Methods: In four hospitals we prospectively recorded the rate of tPA use in consecutive patients admitted with acute ischemic stroke and in those admitted within 3 hours, the reasons why thrombolysis was not given, and the potential gain in the rate of tPA use if all patients had been admitted within 3 hours considering all exclusion criteria other than time., Results: We recruited 486 patients (258 men; mean age, 70.4 +/- 13.5 years), of whom 154 (31.7%) were admitted within 3 hours. The time of stroke onset was unknown in 28 (5.8%). The rate of tPA use was 11.1% in the whole study population and 35.1% in those admitted within 3 hours. In 'eligible' patients, TIA in 33 patients (21.4%), age >80 years in 27 (17.5%), mild stroke in 27 (17.5%), rapidly recovering stroke in 9 (5.8%), a too long door-to-needle time in 8 (5.2%), and severe hypertension in 5 (3.2%) were the main reasons for not to treat. Two patients were not treated despite the absence of documented reasons. If all patients had hypothetically been admitted within 3 hours, the rate of tPA use would have increased from 11.1% up to 27.9% of the whole population and up to 37.4% if aged patients and those with no documented reasons or with a rapidly recovering stroke had also been considered for treatment., Conclusions: Delayed presentation to hospital is the main factor limiting the use of thrombolysis in acute stroke, but additional patients would be treated if those with no contraindication, advanced age or rapidly recovering stroke were considered as eligible.

Background: Impaired mitochondrial phosphorylation potential may play a role in migraine pathogenesis. Metabolic enhancers, such as riboflavin or coenzyme Q, are effective in migraine prophylaxis and quasi-devoid of adverse effects. Thioctic acid (-lipoic acid) is another substance known to enhance energy metabolism in mitochondria and to be beneficial in diabetic neuropathy., Objective: After an open pilot study suggesting its therapeutic antimigraine potentials, we embarked therefore in a randomized controlled trial of thioctic acid (Thioctacid) in migraine prophylaxis steered by the Belgian Headache Society., Methods: Five Belgian centers recruited 54 migraineurs (43 migraine without aura, 11 with aura; mean age 38 +/- 8 years; 7 males). After a 1-month single-blinded run-in period, 44 patients received either placebo (n = 18) or thioctic acid 600 mg p.o./day (n = 26) for 3 months., Results: Statistical analysis was carried out on an intention-to-treat basis. Monthly attack frequency tended to be reduced between run-in and the 3rd month of treatment in the thioctic acid group compared to placebo (P= .06). The proportion of 50% responders was not significantly different between thioctic acid (30.8%) and placebo (27.8%). Within-group analyses showed a significant reduction of attack frequency (P= .005), headache days (P= .009), and headache severity (P= .03) in patients treated with thioctic acid for 3 months, while these outcome measures remained unchanged in the placebo group. No adverse effects were reported. For logistical reasons this trial was interrupted before the planned 80 patients were enrolled., Conclusion: Albeit underpowered, this study tends to indicate that thioctic acid may be beneficial in migraine prophylaxis. Before any firm conclusion can be drawn, however, a large multicenter trial is necessary.

We report the case of a 75-year-old woman who developed involuntary jerks of the abdominal musculature. They occurred spontaneously or triggered by a forced inspiration or attempts to rise from the supine position. Electromyography (EMG) recorded abnormal bursts of muscle activity in the abdominal, thoracic paraspinal, and intercostal muscles up to the 3rd intercostal space. The bursts were bilateral, arrythmic and synchronous in all muscles. Magnetic resonance imaging (MRI) of the spine revealed a syringomyelic cavity between the T3 and T10 levels. The topological correlation between the EMG muscle activities and the MRI findings was consistent with spinal myoclonus arising from the thoracic spinal cord. The synchronous bursts in muscles depending from few adjacent spinal segments suggested the diagnosis of segmental spinal myoclonus (SSM). There are few reports of SSM related to syringomyelia in the literature.

In secondary prevention, reduction of the risk of recurrent ischemic stroke might be expected with statins if a correlation can be established between hyperlipidemia and ischemic stroke or some specific ischemic stroke/TIA subtypes. However, such correlation remains controversial, and more particularly with the etiologic stroke/TIA subtypes. Few studies have evaluated the plasma lipid profile in different ischemic stroke subtypes, and notably in lacunar infarctions and cardioembolic strokes. The objectives of this case-control study was to determine (1) which cholesterol fractions is associated with large vessel disease (LVD), small vessel disease (SVD), and cardioembolic disease (CED); (2) whether hypertriglyceridemia is related more to any particular stroke subtype; and (3) whether the lipid profile is different between LVD and SVD which are both responsible for atherothrombotic cerebral ischemia. From a cohort of 485 patients, were selected 240 consecutive cases with ischemic stroke (n = 182) or transient ischemic attack (n = 58) due to a single etiology. The levels of total cholesterol (total-C), LDL-cholesterol (LDL-C), HDL-cholesterol (HDL-C), and triglycerides (TG) were measured in 61 patients with LVD, in 65 with SVD, and in 114 with CED, and compared with age- and sex-matched control subjects. Additional analysis was performed to compare the lipid profile between LVD and SVD after adjustment for other risk factors. Compared to controls, the total-C level was significantly higher in patients with SVD (p = 0.005) and LVD (p = 0.018). A significant increase in the LDL-C level (p < 0.004) and a significant decrease in the HDL-C level (p = 0.001) were only observed in the LVD patients. The three stroke subtypes showed higher TG levels than the controls (CED, p = 0.037; SVD, p < 0.001; LVD, p = 0.014). The plasma lipid profile was similar in the SVD and LVD subtypes except for HDL-C, which was significantly lower in LVD than in SVD (p = 0.047). Logistic regression adjusted for confounders showed that decreased HDL-C (p = 0.020), and smoking (p = 0.019) were significant discriminative factors for LVD vs. SVD. In conclusion, this controlled study shows that hypertriglyceridemia is commonly found in patients with ischemic cerebrovascular disease whatever the etiologic subtype, whereas hypercholesterolemia is related more to SVD and LVD. In addition to hypertension and diabetes, hypercholesterolemia may also be involved in the etiology of SVD and differs from LVD by a lower decrease in HDL-C.

We report on a case of nocturnal headache attacks fulfilling the criteria for hypnic headache syndrome. Using an overnight polysomnography, one nocturnal headache attack was captured during the REM phase of sleep. Quality of sleep was poor with desaturation episodes. However, the hypnic headache attack was not associated with oxygen desaturation. This additional case supports the view of a relationship between the hypnic headache syndrome and the REM sleep stage. Lithium therapy decreased the intensity and frequency of headache attacks.

Atherothrombotic ischemic stroke is associated with multiple vascular risk factors, including mainly hypertension, diabetes, and hyperlipidemia. Medical therapy of cerebral atherothrombosis implies control of these vascular risk factors and antithrombotic drugs as well. This paper reviews the current therapeutic guidelines according to the randomized trials for primary and secondary stroke prevention.

The annual incidence of cerebrovascular diseases in Belgium is between 200 and 230/100,000 inhabitants. Mortality after stroke is about 21% and approximately 30% of stroke patients will be dependent on others. Cost is mainly related to the length of hospital stay but also to outpatient care. Length of stay is dependent on stroke severity at entry, stroke location (total infarct in the anterior circulation costs twice as much as small lacunar infarcts), and the social status (patients living alone or in a nursing home have a longer length of stay gene-rating a higher cost). Stroke units by using rationalized acute stroke therapy (including thrombolysis) reduce death and disability and decrease the length of stay by acting on stroke severity and co-morbidities. Stroke units also facilitate early discharge by coordinating outpatient care with the general practitioners, rehab centers, and nursing home. A global stroke-based prospective payment should be implemented in Belgium.

The purpose of these guidelines is to assist nuclear medicine practitioners in recommending, performing, interpreting, and reporting the results of brain perfusion SPECT studies using Tc-99m radiopharmaceuticals and brain metabolism PET studies using F-18 fluorodeoxyglucose (FDG). These guidelines have been adapted and extended from those produced by the Society of Nuclear Medicine (Juni et al., 1998) and the European Association of Nuclear Medicine by a Belgian group of experts in the field trained in neurology and/or nuclear medicine. Some indications are not universally approved (e.g. brain death), but largely supported by the literature. They have been included in these guidelines in order to provide recommendations and a standardised protocol.

We studied the time of arrival of 235 consecutive patients admitted to the emergency department of a University Hospital located in a rural area after the first symptoms of ischemic stroke or TIA. Among the following factors, we determined those that might be involved in delayed admission: place of symptom onset, time and place of onset of the first symptoms, contact with a general practitioner before admission time, mode of transportation, clinical score, impairment of consciousness, presence of seizures, heart complaints or headache, age and past medical history of cerebrovascular, cardiovascular and hypertension diseases. Half of the patients arrived within 4 h 10 of symptom discovery and 55 p. cent arrived within 6 hours. The percentage of patients arriving within 3 h (p = 0.001) and 6 h (p = 0.001) was higher for those who had a stroke during the day (8 a.m.-8 p.m.) than during the evening and night. The other characteristics associated with a shorter delay included a low neurological score on the Mathew's Stroke Scale (p < 0.001 at 3 h and p = 0.001 at 6 h) and younger age (p = 0.015 at 3 h). Presence of headache delayed admission (p = 0.010). Forty-five percent of patients arrive at the hospital 6 hours after the discovery of symptoms, too late to receive optimal stroke therapy. Widespread public education on stroke is necessary to reduce the delay of admission, particularly for old patients and in case of mild to moderate deficits.

Early intravenous thrombolysis within the first three hours has been considered in the United States as the first proven treatment in acute ischemic stroke. However, not all patients will respond to this therapy which is also associated with a risk of symptomatic, including fatal, intracranial hemorrhage. This overview addresses the issue of efficacy and safety of intravenous alteplase (tPA) in acute cerebral ischemia. The rationale for thrombolytic therapy and its limits are described. The controlled studies show that intravenous tPA is effective and safe when given under restrictive conditions within 3 hours after stroke onset, but the data for a larger therapeutic window between 3 and 6 hours remain controversial. The expected functional improvement and the risk of intracranial hemorrhage greatly depend on selective clinical and imaging criteria. For this purpose, MRI, using the diffusion- and perfusion-weighted sequences combined with MR- angiography, should be preferred to CT scan in the next future. Applicability of tPA thrombolysis in current neurological practice in Belgium is discussed. Before its generalization, this therapy should be restricted to specialized stroke centers and all treated patients should be recorded in a central data bank to guarantee continued surveillance.

We report paradoxical and ambiguous imaging findings in a patient with transient ischaemic attack (TIA). Perfusion-weighted (PW) MRI obtained 2 hours after symptoms onset showed a hypoperfused area in a region compatible with the focal deficit, while diffusion-weighted (DW) MRI was considered negative. Despite the complete resolution of the symptoms which had already begun at the end of the first MR examination, follow up DW MRI at 3 days showed partial conversion to hyperintensity of the initially hypoperfused area. This case illustrates that PW and DW MRI have to be used in combination and at different time points to correctly diagnose and manage ischaemic stroke because PW MRI is more sensitive than DW MRI for very early detection of ischaemia and delayed DW MRI provides the final signature of brain damage even in case of complete clinical recovering.

Event-related potentials are electric brain manifestations evoked by mental activities. This neurophysiological technique is able to describe temporal succession of cognitive processing and allows to measure the neurobiological correlates of each cognitive activity. The evoked potentials of the oddball paradigm and the Contingent Negative Variation (CNV) are also concerned by clinical applications in neuropsychiatry, in neurology and in psychopharmacology. In the case of migraine, the studies with CNV recorded between migraine attacks are characterized by two major phenomena, cerebral hyperreactivity and lack of habituation to repetitive stimuli. From cognitive point of view, this can be interpreted as a difficulty from migraine sufferers to adapt their information-processing to environmental constraints. From neurological point of view, this trouble is related with dysregulation of norepinephrin and serotonin ascending pathways. Studies with the oddball paradigm potentials remain non consistent. The mismatch between different methodologies could explain such a lack of consistency. The neurophysiological studies have contributed to new physiopathological hypothesis of migraine. Those hypothesis reveal that a shift in the brain metabolic homeostasis could be the common factor of migraine attacks. The clinical contribution of event-related potentials is of little use in the diagnosis of migraine. But two purposes have been suggested: the differential diagnosis between common migraine and tension-type headaches and the monitoring of beta-blocking agents prophylaxis.

Spasticity is usually treated by rehabilitation, orthosis, chemical denervations, orthopaedic surgery and neurosurgery. Selective fascicular neurotomy is a neurosurgical procedure consisting in partial section of selected motor nerves innervating spastic muscles. Neurotomy is indicated in cases of localised disabling spasticity without musculotendinous shortening, resistant to chemical denervation and for which a motor nerve block with anaesthetic has given a good functional result. Neurotomy includes division of the afferent Ia and Ib fibers, unable to recover, leading to permanent disappearance of the spasticity. Neurotomy also includes section of the motor efferent fibers with transient paresis as a result. In adults, neurotomy provides functional improvement in 81 to 97% of cases. In case of posterior tibial neurotomy, improved walking stability and a decrease in foot equinus and knee recurvatum is observed. In children, the risk of deformity recurrence seems higher because of motor axonal reinnervation: indications must therefore be carefully considered and rehabilitation provided after surgery.

Cost-effectiveness and cost per successful treatment has been evaluated in 186 outpatients randomised to treat moderate to severe migraine attacks either with subcutaneous sumatriptan 6 mg (n = 97) or with their current therapy (n = 89) during an open, multicentre study of 3 months. Within 2 hours, headache severity decreased to none/mild in 86% of all attacks in the sumatriptan group (STG) compared to 25% in the customary group (CTG). Migraine was alleviated earlier in the STG than in the CTG (median 3.78 vs. 13.39 hours, p < 0.0001). The direct and total cost of treatment was 133 and 2012 BF, respectively, in the CTG and 1400 and 2522 BF, respectively, in the STG. Measuring the effectiveness of earlier pain relief with sumatriptan, the incremental cost-effective ratios for direct and total cost were 132 and 53 BF per hour of relieved pain, respectively. For this price, significantly more sumatriptan patients improved their quality of life by more than 20% (61.6 vs. 20.6% patients, p < 0.001) and less sumatriptan patient consulted a medical professional (11.3 vs. 29.2% patients, p < 0.01), used less medication for adverse events (6.2 vs. 22.5%, p < 0.001) and suffered less from associated migraine symptoms. The median number of hours of diminished work-efficiency (3 vs. 7 hours, p < 0.01) or of suspension of non-professional activity (10 vs. 24 hours, p < 0.001) was also significantly lower in the STG. The total cost per successfully treated patient was lower in the STG. Sumatriptan is more effective, provides a better quality of life, reduces health care resource utilisation, and improves work productivity as compared to the CTG, thereby resulting in a favourable cost-effectiveness ratio.

The authors describe the clinical and biological data of seven patients with anti-Hu antibodies. Six of them displayed a small cell lung carcinoma (SCLC), but no cancer was detected in the 7th patient in spite of an extensive workup. The clinical heterogeneity of the anti-Hu syndrome is emphasized. The major symptoms were linked to a severe sensory neuropathy in three cases, to cerebellitis in two cases, to dysautonomia in one case, and to gastro-intestinal pseudo-obstruction in one case. One patient also displayed EMG abnormalities characteristic of the Lambert-Eaton myasthenic syndrome. Two patients developed opsoclonus or ocular flutter associated with severe confusion in the late stage of their disease. In four patients, the neurological signs and symptoms preceded the discovery of the SCLC, and in two cases the initial detection of anti-Hu antibodies prompted the successful search for this tumor. Immunopathological events injuring the peripheral and central nervous system are briefly discussed.

Ischemia in the carotid artery territory due to atherosclerotic stenosis of the innominate artery is rare. We report a case in which transcranial Doppler ultrasonography (TCD) and SPECT with acetazolamide challenge proved the hemodynamic mechanism. The patient presented with three hypotensive TIAs in the right middle cerebral artery territory. Angiography showed a tight innominate artery stenosis and subclavian steal but no coexistent carotid or vertebrobasilar lesion. SPECT showed disturbed regional blood flow in the middle cerebral artery territory along with an exhausted perfusion reserve capacity. After angioplasty, flow velocities were normal and the perfusion reserve was restored. SPECT should be used to select patients at risk susceptible to benefit from angioplasty.

Atrial septal aneurysm (ASA) is now recognized as a source of emboli. Its prevalence in a general population remains controversial. We assessed, in a cardiologic population, the prevalence of ASA, the association with cerebrovascular events, the role of associated interatrial shunting and age. Four hundred and ninety-four consecutive patients were referred for transesophageal echocardiography with contrast. The prevalence of ASA in two groups, with (A) and without (B) cerebrovascular events were compared. In group A, we studied the prevalence of ASA according to the clinical presentation (stroke, TIA and peripheral emboli in limbs). An ASA was found in 38 patients (8%). The prevalence of ASA was higher in group A (16%) than in group B (4%) (p < 10(-5)). Prevalence of ASA was not significantly different in stroke, TIA and peripheral emboli subgroups. There was no difference in prevalence of ASA in stroke or TIA subgroups according whether age was < 55 years or > or = 55 years. Prevalence of all types of vascular events was increased when ASA was associated with an interatrial shunt. Our results support the assumption that ASA is a potential source of cerebrovascular events, whatever the clinical presentation or age. Presence of interatrial shunt increases the risk of stroke in subjects with ASA.

Pharyngo-oesophageal dyskinesias present a common symptomatology associated with those difficulties in swallowing for which the radio-manometric assessment is well known. Radiology, nevertheless, with an overall analysis of deglutition and its iatrogenic complications, as well as manometry of the superior oesophageal sphincter (OSS) with its diversity of results, according to the material, techniques, age, sex and stress involved, has convinced us of the necessity for a supplementary dynamic examination. Electromyography (EMG), simultaneously by the inferior constrictor (IC) and cricopharyngeal (CP) muscles, analyses with precision the electric activity of these two muscles, as well as the pharyngosphincteral synchronism. It is an easy examination, reproducible and without complications. In less than one year, nineteen patients suffering exclusively from a pharyngo-oesophageal dyskinesia benefited by this complete assessment. The secondary aetiologies are clearly predominant. Gastro-oesophageal reflux represents a quarter of those detected by an anamnesis alone. EMG detects 68% of functional anomaly of the OSS; manometry finds 47% and radiology 32%. Extramucosal myotomy of the OSS concerns incomplete or uncoordinated relaxation, preferentially by left cervical approach. The preliminary results, both clinical and manometric, are very satisfactory.

The relationship between the presence of silent cerebral infarcts (SCI) and etiology of an acute cerebral ischemia remains controversial. In a population of 306 patients with a first-ever stroke (225) or transient ischemic attack (TIA) (81), we studied the prevalence and associated risk factors of SCI as well as the presumed etiology of the qualifying event. Silent infarction was defined as a focal hypodensity on brain CT, not related to the recent ischemic event. The overall prevalence was 33% (102/306) with a higher rate in stroke patients (83/225, 37%) than in TIA patients (19/81, 23%; p = 0.028). Age (p < 0.01), smoking (p < 0.01), hypertension (p = 0.013), and leukoaraiosis (p = 0.05) were significantly associated with SCI, but only in some degree in TIA patients. Presence of SCI was statistically associated with a small-artery disease (p < 0.01) considered as the cause of the qualifying event. Emboligenic cardiopathy was significantly more frequent in patients without SCI (p < 0.05) in the TIA subgroup. Thus, in patients with silent cerebral infarcts, small-vessel disease may be in most cases the cause of the recent symptomatic cerebral ischemia.

Five right-handed patients with pure transient global amnesia were evaluated with technetium-99m hexamethylpropyleneamine oxime single photon emission computed tomography after the amnesic attack. Independent of the interval between the procedure and the amnesic episode, single photon emission computed tomography demonstrated a decreased cerebral blood flow in the left temporal lobe in one patient and in the left parietotemporal region in three patients, with a more marked reduction in the temporal lobe. The remaining three patients were normal. A control single photon emission computed tomographic study was carried out in one patient 3 months after the amnesic attack and showed a left-sided persistent temporal hypoperfusion. These findings suggest that in some patients, transient global amnesia can be due to a vascular mechanism requiring strong investigations for vascular risk factors and appropriate treatment. During a follow-up period of 12 to 32 months, none of the patients with regional hypoperfusion suffered cerebrovascular events, suggesting that single photon emission computed tomography has no predictive value for further stroke.

Neurological complications of myeloma are multiple and various. Cranial and intracranial locations have been rarely reported. They can be classified into three clinical groups: (1) cranial nerve palsies secondary to single or multiple lesions in the base of the skull, (2) intraorbital tumors, (3) intracranial tumors, either cranial myeloma extending intracranially or pure intracranial tumor (dural and/or cerebral). In our case, macroscopic and microscopic examination of the brain showed dural and cerebral involvement, confirmed by immunohistochemical studies. The radiological features are discussed (CT scan, MRI, angiography). To our knowledge, a single report of intracranial plasmacytoma documented by MRI has been reported in the literature.

A 72 year-old-man presented with right hemiparesis and global aphasia related to a large infarct in the left middle cerebral artery territory. A left carotid angiography revealed internal carotid artery occlusion and vascular blush just below the base of the skull. The blush was supplied by branches from the external carotid artery. Cervical CT-scan showed a large tumor centered by the left internal carotid artery. At cervical surgery, the internal carotid artery was compressed and infiltrated by the tumoral process: a benign paraganglioma. The site below the base of the skull and the connection between tumor and vagal nerve suggested a vagal paraganglioma. To our knowledge, this is the first case of cerebral infarction and internal carotid artery occlusion revealing a vagal paraganglioma.

Background and Purpose: Hypertension is commonly considered the major cause of lacunar infarctions. However, in some cases, it has been suggested that lacunes could be caused by cerebral emboli from cardiac or carotid sources. Cholesterol cerebral emboli have been rarely reported as a cause of lacunes., Case Description: We describe a 79-year-old patient with a progressive multi-infarct dementia who developed transient motor aphasia and paresis of the right arm. Computed tomography showed lacunar infarcts in the right caudate nucleus, left thalamus, and left putamen, as well as an old right frontal infarction. Neuropathological examination demonstrated no prominent vascular hyalinosis, but did show multiple cholesterol emboli occluding small arteries around lacunar infarcts and leptomeningeal arteries near cortical infarcts. The cholesterol material presumably originated in the extended atheromatous changes along the aortic arch., Conclusions: Our report confirms that lacunes can be caused by cholesterol emboli in some patients. Small cerebral emboli should not be overlooked as a cause of lacunes.

The authors report one case of Graves' ophthalmopathy with a palpebral asymmetry, which was characterized by a left ptosis and a right palpebral retraction. In connection with Graves' disease, many ocular signs were described, including exophthalmos, ophthalmoplegia, palpebral retraction and visual loss, but unilateral ptosis was rarely reported. The orbital CT-scanning demonstrated the bilateral enlargement of the extraocular muscles, due to the infiltrative process met in Graves' disease. The ptosis and the palpebral retraction were suspected to be related to the extension of this infiltrative process in the levator palpebrae.

The role of platelet serotonin in migraine remains a subject of controversy. However, the frequency of association of migraine with antibody-mediated thrombocytopenia would suggest that platelet dysfunction or impaired serotonin metabolism might play a role in migrainous attack. We report three new cases, two involving chronic idiopathic thrombocytopenia and one lupus. The observation of high levels of anti-platelet antibodies in close correlation with the occurrence of attacks suggests that the Serotonin Releasing Factor (SRF) could be concerned. This was suspected previously on the basis of in vitro studies. The hypothesis that other forms of migraine might be linked to an immunopathological process involving other immunoglobulins is proposed (Acta neurol. belg., 1988, 88, 290-296).

The authors describe three patients with a chronic sensory-motor polyneuropathy associated with a monoclonal IgM gammopathy. In each case, the M-component was shown to display an antibody activity against the Myelin-Associated Glycoprotein (MAG) in a western blot technique. Sera from the three patients stained specifically the myelin sheaths of normal human peripheral nerves after incubation with rabbit anti-IgM. Motor conduction velocities were very low in each case. Morphological studies of the sural nerve from one patient revealed a moderate loss of myelinated fibres, some onion-bulbs but also a microangiopathy and signs of axonal degeneration.

Sensory subacute neuropathies associated with sicca syndrome without any systemic involvement have been reported rarely. A sixth case is described with what appears to be the first report of muscle and nerve biopsy findings. The histological studies revealed axonal degeneration without vasculitis in the sural nerve, and a slight denervation process and a discrete myositis in the gastrocnemius muscle, reflecting a subtle systemic disorder. The clinical course of a long-standing subacute sensory neuropathy, the biopsy-documented axonal degeneration, and the neurophysiological findings suggest involvement of the dorsal root ganglia.