Gender-specific differences in stroke knowledge, stroke risk perception and the effects of an educational multimedia campaign.

This study aimed at identifying gender-specific differences in stroke knowledge, stroke risk perception and the educational effects of a multimodal educational intervention. We performed computer-assisted telephone surveys among an average sample of 500 members of the general public (44.0% male, 56.0% female), before and immediately after an intense 3-month educational stroke campaign in a western German area of 400,000 inhabitants. The intervention was comprised of poster advertisements and various print media. Slogans and stroke interest stories appeared regularly in local newspapers, on television and radio and public events focussed on the subject. Even before the intervention, more women than men were able to name at least one stroke warning sign (71.3 vs. 57.8%, p < 0.01), to name the correct emergency call number (33.3 vs. 24.3%, p < 0.05) or to cite the correct action in acute stroke ("call emergency care", 87.2 vs. 70.1%, p < 0.001). In some aspects women showed a generally better improvement of knowledge after the campaign (e.g. correct emergency call number: +5.7 vs. +1.2%, p < 0.05). Fewer women than men considered themselves as being at risk of stroke (30.9 vs. 36.9%. p < 0.01) with a significant increase following the intervention in both sexes (38.9/46.0%, p < 0.01). The perception of different educational media varied between the sexes. For example, female sex was independently associated with a better recall of poster advertisements and flyers in pharmacies and at the doctor's office (OR 1.44). Our data indicate that educational programs do have gender-specific effects. Women show a better stroke knowledge and in some aspects a better chance to gain information from classical broad educational interventions. Future campaigns should be tailored economically, and should focus different media and educational messages on the two sexes accordingly.

An educational multimedia campaign has differential effects on public stroke knowledge and care-seeking behavior.

To study the differential educational effects of a multimodal educational program on public stroke knowledge, we performed computer-assisted telephone surveys among a random sample of 500 members of the general public, before and immediately after an intense three-month educational campaign. The intervention comprised of poster advertisements, flyers, mail circular, slogans, stroke interest stories etc. in local newspapers, on television and radio, and public events. The main outcome measures were stroke knowledge, the intended behavior in acute stroke and the educational media remembered after the intervention. General knowledge of the nature of stroke (65.7% correct answers before versus 84.9 % after the campaign, p < 0.01) and the awareness of being at risk of stroke (32.7 % vs. 41.9%, p < 0.01) increased due to the campaign, especially in respondents of lower educational background. There was no significant effect on the number of patients who would seek emergency medical care after the intervention (81 % vs. 82 %) and hardly any effect on detailed knowledge of stroke warning signs or different risk factors. Mass media like newspapers, radio and television were most frequently reported as the main information source remembered (66.6 %). Our data indicate that educational programs do have differential effects on public stroke knowledge and individual stroke risk,which does not necessarily lead to a change in care-seeking behavior. Repeated information using short-tailored slogans and cues to action led to a gain in general stroke knowledge, especially in high-risk populations of lower educational background. Large educational campaigns seem unsuitable, however, for mediation of detailed information on stroke.

Topodiagnostic implications of hemiataxia: an MRI-based brainstem mapping analysis.

The topodiagnostic implications of hemiataxia following lesions of the human brainstem are only incompletely understood. We performed a voxel-based statistical analysis of lesions documented on standardised MRI in 49 prospectively recruited patients with acute hemiataxia due to isolated unilateral brainstem infarction. For statistical analysis individual MRI lesions were normalised and imported in a three-dimensional voxel-based anatomical model of the human brainstem. Statistical analysis revealed hemiataxia to be associated with lesions of three distinct brainstem areas. The strongest correlation referred to ipsilateral rostral and dorsolateral medullary infarcts affecting the inferior cerebellar peduncle, and the dorsal and ventral spinocerebellar tracts. Secondly, lesions of the ventral pontine base resulted in contralateral limb ataxia, especially when ataxia was accompanied by motor hemiparesis. In patients with bilateral hemiataxia, lesions were located in a paramedian region between the upper pons and lower midbrain, involving the decussation of dentato-rubro-thalamic tracts. We conclude that ataxia following brainstem infarction may reflect three different pathophysiological mechanisms. (1) Ipsilateral hemiataxia following dorsolateral medullary infarctions results from a lesion of the dorsal spinocerebellar tract and the inferior cerebellar peduncle conveying afferent information from the ipsilateral arm and leg. (2) Pontine lesions cause contralateral and not bilateral ataxia presumably due to major damage to the descending corticopontine projections and pontine base nuclei, while already crossed pontocerebellar fibres are not completely interrupted. (3) Finally, bilateral ataxia probably reflects a lesion of cerebellar outflow on a central, rostral pontomesencephalic level.

Somatotopic organization of the corticospinal tract in the human brainstem: a MRI-based mapping analysis.

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

Electrophysiological brainstem testing in the diagnosis of reversible brainstem ischemia.

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