Differential functional benefits of ultra highfield MR systems within the language network

Several investigations have shown limitations of fMRI reliability with the current standard field strengths. Improvement is expected from ultra highfield systems but studies on possible benefits for cognitive networks are lacking. Here we provide an initial investigation on a prominent and clinically highly-relevant cognitive function: language processing in individual brains. 26 patients evaluated for presurgical language localization were investigated with a standardized overt language fMRI paradigm on both 3T and 7T MR scanners. During data acquisition and analysis we made particular efforts to minimize effects not related to static magnetic field strength differences. Six measures relevant for functional activation showed a large dissociation between essential language network nodes: although in Wernicke's area 5/6 measures indicated a benefit of ultra highfield, in Broca's area no comparison was significant. The most important reason for this discrepancy was identified as being an increase in susceptibility-related artifacts in inferior frontal brain areas at ultra high field. We conclude that functional UHF benefits are evident, however these depend crucially on the brain region investigated and the ability to control local artifacts

Primary cerebellar glioblastoma multiforme

Glioblastoma multiforme in adults arising in the cerebellum is a rare tumor, well documented in only 13 cases in the literature. We report a fourteenth case, an 80-year-old female, and reassess the clinical and CT aspects of this tumor based on a review of the world's literature. The median age of patients is 53 years with a median survival of three months, which is less than adult cerebral hemisphere malignant gliomas.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/45390/1/11060_2004_Article_BF00151226.pd

Apomorphine in idiopathic restless legs syndrome: an exploratory study

Background: Dopaminergic and opioidergic drugs have been found to be effective in patients with restless legs syndrome (RLS). Objectives: To test the effect of apomorphine—a combined opioidergic and dopaminergic agonist—and subsequent selective antagonism by naloxone and metoclopramide on subjective and objective symptoms in patients with idiopathic RLS. Methods: Nine patients with RLS were pretreated with oral domperidone for three days. A modified suggested immobilisation test (SIT) was carried out between 8 pm and 1 am under the following conditions of intravenous drug administration: baseline–apomorphine–apomorphine plus naloxone–apomorphine plus metoclopramide. Outcome variables were a visual analogue scale (VAS) of subjective RLS symptoms and EMG documented periodic leg movements while awake (PLMW). Results: Compared with baseline, apomorphine resulted in a rapid and significant improvement in subjective RLS symptoms as measured by VAS (54.5% improvement; p = 0.011), and an almost immediate cessation of PLMW, measured by PLMW index (98.0% improvement; p = 0.012). Neither additional naloxone nor metoclopramide blocked this effect significantly. While given apomorphine with metoclopramide, there was a trend to reappearance of PLMW. Conclusions: Apomorphine may be an effective treatment for idiopathic RLS. Its effectiveness may reflect both to its dopaminergic and its opioidergic activity, and is not diminished significantly by blocking only one of these pathways. The trend to a worsening of the PLMW index with metoclopramide hints at a primarily dopaminergic effect of apomorphine in idiopathic RLS

Supplementary Material for: Neuromagnetic Cortical Activation during Initiation of Optokinetic Nystagmus: An MEG Pilot Study

<p><b><i>Purpose:</i></b> To investigate the spatiotemporal evolution of cortical activation during the initiation of optokinetic nystagmus using magnetoencephalography. <b><i>Background:</i></b> Previous imaging studies of optokinetic nystagmus in humans using positron emission tomography and functional magnetic resonance imaging discovered activation of a large set of cortical and subcortical structures during steady-state optokinetic stimulation, but did not provide information on the temporal dynamics of the initial response. Imaging studies have shown that cortical areas responsible for vision in occipital and temporo-occipital areas are involved, i.e. cortical areas control optokinetic stimulation in humans. Magnetoencephalography provides measures that reflect neural ensemble activity in the millisecond time scale, allowing the identification of early cortical components of visuomotor integration. <b><i>Design/Methods:</i></b> We studied neuromagnetic cortical responses during the initiation of optokinetic nystagmus in 6 right-handed healthy subjects. Neuromagnetic activity was recorded with a whole-head magnetoencephalograph, consisting of 143 planar gradiometers. <b><i>Results:</i></b> The mean (±SD) latency between stimulus onset and initiation of optokinetic nystagmus was 177.7 ± 59 ms. Initiation of optokinetic nystagmus evoked an early component in the primary visual cortex starting at 40-90 ms prior to the onset of the slow phase of nystagmus. Almost simultaneously an overlapping second component occurred bilaterally in the temporo-occipital area (visual motion areas), pronounced in the right hemisphere, starting at 10-60 ms prior to the slow-phase onset. Both components showed long-duration activity lasting for up to 100 ms after slow-phase onset. <b><i>Conclusions:</i></b> Our findings suggest that the initiation of optokinetic nystagmus induces early cortical activation in the occipital cortex and almost simultaneously bilaterally in the temporo-occipital cortex. These cortical regions might represent essential areas for the monitoring of retinal slip.</p

Sleep need in high school athletes

BACKGROUND: Freezing of gait (FOG) is a common and debilitating phenomenon in Parkinson's disease (PD). Wearable accelerometers might help to assess FOG in the research setting. Here, we evaluate whether accelerometry can detect FOG while executing rapid full turns and while walking with rapid short steps (the two most common provoking circumstances for FOG). METHODS: We included 23 PD patients, who all had objective FOG. Participants performed several walking tasks, including walking rapidly with short steps and rapid full turns in both directions with a triaxial linear waist-mounted accelerometer. Two independent experts identified FOG episodes using off-line video-analysis (gold standard). A validated algorithm [ratio between pathological freezing (3-8 Hz)-and normal locomotor frequencies (0.5-3 Hz)] was applied on the accelerometer data to detect FOG episodes. RESULTS: Clinically, FOG was most often observed during full rapid turns (81% of all episodes), followed by walking with short rapid steps (12% of all episodes). During full rapid turns, accelerometry yielded a sensitivity of 78% and specificity of 59%. A sensitivity of 64% and specificity of 69% was observed during walking rapidly with small steps. Combining all tasks rendered a sensitivity of 75% and specificity of 76%. CONCLUSION: Our results suggest that FOG can be detected from a single lumbar accelerometer during several walking tasks, including full rapid turns and walking with short steps rapidly, with reasonable sensitivity and specificity. This approach holds promise for possible implementation as complementary objective outcome in a research setting, but more work remains needed to improve the sensitivity and specificity