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Highlights • We assessed midbrain–hindbrain in a large series of cortical malformation patients. • Midbrain–hindbrain malformations are commonly linked to cortical malformations. • Midbrain–hindbrain malformations are associated with severe clinical phenotype., Summary Midbrain–hindbrain malformations (MHM) may coexist with malformations of cortical development (MCD). This study represents a first attempt to investigate the spectrum of MHM in a large series of patients with MCD and epilepsy. We aimed to explore specific associations between MCD and MHM and to compare two groups of patients: MCD with MHM (wMHM) and MCD without MHM (w/oMHM) with regard to clinical and imaging features. Two hundred and twenty patients (116 women/104 men, median age 28 years, interquartile range 20–44 years at the time of assessment) with MCD and epilepsy were identified at the Departments of Neurology and Pediatrics, Innsbruck Medical University, Austria. All underwent high-resolution MRIs (1.5-T) between 01.01.2002 and 31.12.2011. Midbrain–hindbrain structures were visually assessed by three independent raters. MHM were seen in 17% (38/220) of patients. The rate of patients wMHM and w/oMHM differed significantly (p = 0.004) in three categories of MCD (category I – to abnormal neuronal proliferation; category II – to abnormal neuronal migration; and category III – due to abnormal neuronal late migration/organization): MCD due to abnormal neuronal migration (31%) and organization (23%) were more commonly associated with MHM compared to those with MCD due to abnormal neuronal proliferation (9%). Extensive bilateral MCD were seen more often in patients wMHM compared to those w/oMHM (63% vs. 36%; p = 0.004). In wMHM group compared to w/oMHM group there were higher rates of callosal dysgenesis (26% vs. 4%; p

Metachromatic leukodystrophy (MLD) is a progressive white matter disease caused by arylsulfatase A deficiency. Demyelination in the nervous system is detected by cerebral magnetic resonance imaging (MRI) and neurophysiological studies. We present three children with infantile MLD, who had difficulties in standing and walking with absent reflexes. Protein levels in cerebral spinal fluid (CSF) were elevated and nerve conduction studies revealed slowing down of motor nerve conduction velocity. Initial cerebral MRIs showed no white matter changes. Consecutively, all three children developed clinical symptoms of neurodegenerative disease. Follow-up MRI and arylsulfatase A testing led to diagnosis of MLD. We conclude, that in young children who present with an acute/subacute demyelinating polyneuropathy, MLD is a differential diagnosis.

To assess the effect of caffeine on the functional MRI signal during a 2-back verbal working memory task, we examined blood oxygenation level-dependent regional brain activity in 15 healthy right-handed males. The subjects, all moderate caffeine consumers, underwent two scanning sessions on a 1.5-T MR-Scanner separated by a 24- to 48-h interval. Each participant received either placebo or 100 mg caffeine 20 min prior to the performance of the working memory task in blinded crossover fashion. The study was implemented as a blocked-design. Analysis was performed using SPM2. In both conditions, the characteristic working memory network of frontoparietal cortical activation including the precuneus and the anterior cingulate could be shown. In comparison to placebo, caffeine caused an increased response in the bilateral medial frontopolar cortex (BA 10), extending to the right anterior cingulate cortex (BA 32). These results suggest that caffeine modulates neuronal activity as evidenced by fMRI signal changes in a network of brain areas associated with executive and attentional functions during working memory processes.

Transmeatal cochlear laser (TCL) treatment has recently been proposed as a therapeutic procedure for cochlear dysfunction such as chronic cochlear tinnitus or sensorineural hearing loss. The aim of this study was to investigate whether TLC has any influence on the central nervous system using functional MRI with healthy young adults. The laser stimulation device was placed on the tympanic membrane of both ears. A laser stimulation run and a placebo run were performed in random order. The participants were unable to differentiate between verum and placebo stimulation. In the comparison of verum to placebo runs, we observed significant activations within the left superior frontal gyrus, the right middle and medial frontal gyrus, the right superior parietal lobule, the left superior occipital gyrus, the precuneus and cuneus bilaterally, the right anterior and the left and right middle and posterior cingulate gyrus and the left thalamus. This network of brain areas corresponds well to results from previous PET studies of patients with tinnitus. Though TCL seems to have a clinically measurable effect on the central nervous system the neurophysiological mechanism leading to the observed activated neuronal network remains unknown.

The purpose of this study was to investigate the sensorimotor cortex response to plantar vibrotactile stimulation using a newly developed MRI compatible vibration device. Ten healthy subjects (20-45 years) were investigated. Vibrotactile stimulation of the sole of the foot with a frequency of 50 Hz and a displacement of 1 mm was performed during fMRI (echo-planar imaging sequence at 1.5 T) using an MRI compatible moving magnet actuator that is able to produce vibration frequencies between 0 and 100 Hz and displacement amplitudes between 0 and 4 mm. The fMRI measurement during vibrotactile stimulation of the right foot revealed brain activation contralaterally within the primary sensorimotor cortex, bilaterally within the secondary somatosensory cortex, bilaterally within the superior temporal, inferior parietal, and posterior insular region, bilaterally within the anterior and posterior cingular gyrus, bilaterally within the thalamus and caudate nucleus, contralaterally within the lentiform nucleus, and bilaterally within the anterior and posterior cerebellar lobe. The advantages of the new MRI compatible vibration device include effective transmission of the stimulus and controlled vibration amplitudes, frequencies, and intensities. The results indicate that plantar vibration can be a suitable paradigm to observe activation within the sensorimotor network in fMRI. Furthermore, the method may be used to determine the optimal responsiveness of the individual sensorimotor network.

Zusammenfassung Grundlegende wissenschaftliche Untersuchungen in der Akupunktur sind bisher durch das Fehlen einer rigiden Kontrollbedingung schwierig. Als Kontrolle wurden Nichtakupunkturpunkte und Placebonadeln verwendet. Bei ersteren ist nicht gesichert, dass von ihnen nicht doch physiologische Wechselwirkungen ausgehen und im Ergebnis aufscheinen. Placebonadeln hingegen konnen von Verumakupunktur durch das Fehlen eines DeQi-Gefuhls unterschieden und erkannt werden. Eine Losung kann die Laserakupunktur sein. Hierbei wurden mittels funktioneller Magnetresonanztomographie (f-MRT) vergleichbare und reproduzierbare Ergebnisse wie bei Nadelakupunktur nachgewiesen. Gleichzeitig erlaubt der Laser ein Placebodesign, das vom Patienten/Probanden nicht vom Verum zu unterscheiden ist und keine physiologische Wirkung entfaltet. Durch Verwendung neuartiger Mehr-Kanal-Akupunkturlasergerate mit Computersteuerung konnte auch ein doppelt verblindetes Studiendesign ermoglicht werden.

Language deficits in 10 patients with medically intractable left-sided temporal lobe epilepsy prior to and following selective amygdalohippocampectomy are described. Preoperatively, a pattern of minor linguistic deficits was observed in three patients; isolated minor naming deficits were detectable in one additional patient. Three months after surgery, six patients' linguistic functions were unchanged, whereas in four patients, a significant decline in linguistic functions could be observed. All four patients revealed a very similar language syndrome characterized by reduced language comprehension and fluency, well-articulated speech, frequent word-finding difficulties, circumlocutions, and semantic paraphasias in the absence of any phonological disorder. These deficits remained stable during the 12-month follow-up period. However, magnetic resonance imaging did not show any neocortical lesions outside the resection area. Possible explanations for these findings include neuronal cell loss and deafferentiation in cortical areas, disruption of the basal temporal language area pathways, reorganization of the language network in chronic temporal lobe epilepsy, and neocortical lesions due to the surgical intervention. Furthermore, correlations between linguistic and demographic data for our patients suggest that patients older at epilepsy onset are at greater risk for developing postoperative language deficits.

Hintergrund: Die funktionelle Kernspintomographie (f-MRT) ermoglicht es, funktionelle Aktivierungen des Gehirns nicht-invasiv bildgebend nachzuweisen und diese Funktionen bestimmten Hirnarealen zuzuordnen. Anhand zweier Laserakupunkturstudien an den Punkten Bl 67 und Gb 43 sollte mittels f-MRT die Akupunkturwirkung auf das menschliche Gehirn untersucht werden. Methode: An den Studien nahmen 10 bzw. 11 gesunde mannliche Probanden teil. Es wurden am linken Punkt Bl 67 und an beiden Punkten Gb 43 sowohl Laserakupunktur als auch Placeboakupunktur durchgefuhrt. Weiterhin wurde ein NichtAkupunkturpunkt untersucht. Alle Versuche wurden an einem 1,5 Tesla MR-Scanner durchgefuhrt. Die Auswertung erfolgte mit der Software SPM99. Ergebnisse: Die Laserakupunktur an den Punkten Bl 67 und Gb 43 bewirkte jeweils ipsilaterale Aktivierungen in den Brodmann-Arealen (BA) 18 und 19 (Bl 67), 40 und 22 (Gb 43 re.), Nucleus ruber und Substantia nigra (Gb 43 li.) sowie Aktivierungen des ipsilateralen Hirnstamms (Gb 43 re./li.). Die Placebountersuchung und die Untersuchung an einem Nicht-Akupunkturpunkt fuhrten zu keinen Aktivierungen. Schlussfolgerung: Wir konnten zeigen, dass die Laserakupunktur an den Punkten Bl 67 und Gb 43 zu spezifischen ipsilateralen Aktivierungen von kortikalen und subkor-tikalen Hirnarealen fuhrt. Der Vergleich mit einer vorhergehenden Nadelakupunkturstudie zeigt, dass Laserakupunktur einen ahnlichen Einfluss auf den zerebralen Kortex aufweist wie Nadelakupunktur. Dies ist ein weiterer Hinweis fur die Effektivitat und das therapeutische Potenzial der Laserakupunktur. Weiterhin zeigen die Ergebnisse, dass die f-MRT ein hilfreiches Mittel ist, um die therapeutischen Wirkungen der Akupunktur zu untersuchen und besser verstehen zu konnen.

To evaluate biochemical changes in contrast-enhancing multiple sclerosis (MS) lesions, we examined 14 patients with relapsing-remitting MS at acute clinical exacerbation with the help of contrast-enhanced magnetic resonance imaging (MRI) and 1H magnetic resonance spectroscopic imaging (1H MRSI). Using a 1.5-tesla MR system (Magnetom Vision, Siemens, Germany), we followed 29 contrast-enhancing and 24 nonenhancing MS lesions as well as normal-appearing white matter (NAWM) before and during high-dose methylprednisolone (HDMP) therapy. Metabolite ratios of N-acetylaspartate (NAA), choline (Cho), creatine (Cr), and lactate (Lac) were calculated. A transient decrease in contrast enhancement under HDMP therapy was observed. Both groups of MS lesions showed significantly decreased NAA to Cr ratios compared to NAWM with no changes in time. Baseline 1H MRSI revealed significantly increased Cho to Cr ratios in the contrast-enhancing MS lesions (1.13 +/- 0.25) compared to the nonenhancing MS lesions (0.85 +/- 0.26, P0.001) and NAWM (0.97 +/- 0.22, P = 0.015). Both the contrast-enhancing and the nonenhancing MS lesions exhibited a significant increase in Cho to Cr ratios from the second to the third 1H MRSI. We identified resonances of lactate in both groups of MS lesions and NAWM without any significant group differences or changes over time. 1H MRSI provides additional information that help to estimate macrophages' activity, cell membrane activation, and neuronal impairment within MS lesions. We believe that combined contrast-enhanced MRI and 1H MRSI may help to further investigate inflammatory processes within active MS lesions and should be employed more frequently to the research on therapy effects in MS.

Functional magnetic resonance imaging was used to compare cortical activation patterns in healthy volunteers with those in patients with schizophrenia during a modified verbal Stroop task. Healthy subjects (n=13) and patients with schizophrenia (n=13) on stable antipsychotic treatment, matched on demographic variables, were included. Patients were preselected on the basis of good performance on a selective attention test. Patients with schizophrenia showed a significantly increased pattern of activation in the left and right inferior frontal cortex and the anterior cingulate cortex. A significant negative correlation between activation of the left prefrontal cortex and accuracy in the modified Stroop test was observed for healthy controls but not schizophrenia patients. Although both groups recruited the prefrontal cortex during the modified Stroop task, for the schizophrenia patients this activation was bilateral, whereas for the controls this activation was primarily in the left hemisphere, suggesting that patients with schizophrenia recruited more prefrontal regions to perform the task with the same accuracy as healthy controls. Our findings of increased activity across multiple areas of the brain, including dorsolateral frontal cortex and anterior cingulate, in patients with schizophrenia who perform relatively well on a task of selective attention give further evidence that task performance may be a confounding factor in the interpretation of neuroimaging results.

The purpose of this study was to investigate the fMRI response of the sensorimotor cortex to a vibration paradigm produced by a novel vibrotactile stimulator. Fifteen contiguous slices covering the sensorimotor cortex parallel to the anterior (AC) and posterior commissure (PC) line were obtained with echoplanar magnetic resonance imaging at 1.5T. Cortical activity in ten healthy subjects (20-45 years) was investigated during vibration (50 Hz) of the palm of the right hand and compared to a finger-to-thumb tapping paradigm. For the vibration paradigm a mechanically driven vibration head was mounted on the palm of the right hand. The new vibration device produces vibration frequencies (1-130 Hz) and displacement amplitudes (0.5-4 mm) suitable to elicit the tonic vibratory reflex. The fMRI measurement during vibratory stimulation revealed activation in the pre- and postcentral gyrus in all subjects. These activations were comparable to the finger-to-thumb tapping paradigm. The advantages of the new MR compatible vibration device include effective transmission of the stimulus and controlled vibration frequencies and intensities. These preliminary fMRI results indicate that vibration can be an alternative paradigm for the evaluation of sensory and motor functions in patients unable to perform active motor paradigms.

The aim of the study was to implement a vibrotactile stimulator using functional magnetic resonance imaging (fMRI). A fMRI compatible vibration device consisting of a pneumatically driven dual membrane pump was developed. Brain activation during 50 Hz vibrotactile stimulation of the right hand-palm were compared to a right 2 Hz finger-to-thumb-tapping in ten healthy, right-handed male volunteers. The vibration paradigm showed a comparable activation pattern with respect to finger-to-thumb-tapping in the contralateral perirolandic region. The advantage of the new vibration device is the possibility to elicit the vibratory-tonic-reflex due to the higher amplitude in context with the high frequency than established devices. This reflex is considered to be responsible for the activation in the primary motor cortex and the current paradigm might prove useful in future neurosurgical planning in patients with perirolandic lesions.

Anesthesia for diagnostic procedures, e.g., MRI measurements, has increasingly used sevoflurane and nitrous oxide in recent years. Sevoflurane and nitrous oxide are known cerebrovasodilatators, however, which potentially interferes with MRI examination of cerebral hemodynamics. To compare the effects of relevant equianesthetic concentrations (0.4 MAC) of both drugs on regional cerebral blood flow (rCBF) and regional cerebral blood volume (rCBV) we used contrast-enhanced magnetic resonance imaging (MRI) perfusion measurement, which has the advantage of providing regional anatomic resolution. Sevoflurane increased rCBF more than did nitrous oxide in all regions except in parietal and frontal gray matter. Nitrous oxide, by contrast, increased rCBV in most of the gray matter regions more than did sevoflurane. In summary we show that, in contrast to nitrous oxide, sevoflurane supratentorially reversed the anterior-posterior gradient in rCBF and typically redistributed rCBF to infratentorial gray matter. In contrast, nitrous oxide increased rCBV more than did sevoflurane. Both inhalational anesthetics had a drug-specific influence on cerebral hemodynamics, which is of importance when interpreting MRI studies of cerebral hemodynamics in anesthetized patients.

Purpose: To report a case of cerebral ischemia confirmed by magnetic resonance imaging after successful cardiopulmonary resuscitation (CPR) complicated by acute respiratory injury. Materials and methods: After 4 min of cardiac arrest, followed by 3 min of basic life support CPR, a female pig weighing 38 kg received every 5 min vasopressin (0.4, 0.4 and 0.8 U/kg). After 22 min of cardiac arrest, including 18 min of CPR, one defibrillation attempt employing 100 J resulted in return of spontaneous circulation. Neurological evaluation was performed 24 and 96 h after successful CPR. Magnetic resonance imaging was carried out 4 days after CPR using a clinical 1.5 T scanner. The magnetic resonance imaging protocol consisted of fast spinecho T2-weighted, as well as spinecho T1-weighted imaging of the brain. Results: CPR with vasopressin resulted in excellent coronary perfusion pressure ranging between 35 and 60 mmHg throughout CPR. Eight minutes after initiation of chest compressions, bleeding out of the tracheal tube occurred. This was later confirmed as originating from bilateral bloody pulmonary infiltrations, resulting in acute respiratory injury in the post-resuscitation phase. Ninety-six hours after successful CPR, magnetic resonance imaging revealed bilateral diffuse cerebral vasogenic edema. Conclusion: Although excellent coronary perfusion pressure renders a return of spontaneous circulation more likely, complications such as acute respiratory injury in the post-resuscitation phase have to be managed carefully in order to ensure good neurological recovery from cardiac arrest.

The effects of embryonic neural transplantation in experimental models of neurodegenerative disorders are commonly assessed by behavioral tests and postmortem neurochemical or anatomical analysis. The purpose of the present study was to evaluate embryonic neuronal grafts in a novel rat model of multiple system atrophy (MSA) with the help of in vivo magnetic resonance imaging (MRI) and to correlate imaging with histological parameters. Striatonigral double lesions were created in male Wistar rats by unilateral intrastriatal injection of 3-nitropropionic acid (3-NP). Seven weeks following lesion surgery animals were divided into four transplantation groups receiving either pure mesencephalic, pure striatal, mesencephalic-striatal cografts, or sham grafts. In vivo structural imaging was performed 21 weeks after transplantation using a whole body 1.5 Tesla MR scanner. The imaging protocol comprised T2-weighted TSE and T1-weighted TIR sequences. Immunohistochemistry using DARPP-32 as striatal marker and tyrosinhydroxylase as marker for nigral neurons was performed for correlation analysis of imaging and histological parameters. The sensitivity of graft detection by in vivo MRI was 100%. The graft tissue was clearly demarcated from the remaining striatal tissue in both T2- and T1-weighted sequences. Morphometrically, cross-sectional areas of the grafts and spared intact striatum as defined by immunohistochemistry correlated significantly with measurements obtained by in vivo MRI. In conclusion, we were able to evaluate in vivo both lesion-induced damage and graft size in a 3-NP rat model of MSA using a conventional whole body 1.5 Tesla MRI scanner. Additionally, we obtained an excellent correlation between MRI and histological measurements.

The decrease in intracellular creatine concentration observed in a number of muscle diseases may deplete energy homeostasis and may, therefore, be one of the factors determining and/or aggravating muscle weakness and degeneration. Two hypotheses are put forward in the present communication to explain: (i) the mechanisms leading to the disturbances in creatine metabolism found in various muscle diseases; and (ii) the potential of oral creatine supplementation in alleviating the clinical symptoms.

Today, patients with alveolar rhabdomyosarcoma have a favorable prognosis with a survival rate of more than 80%, due to modern radiotherapy. However, those patients with secondary meningeal involvement are still afflicted with a mortality rate of 90% unless a different therapeutic approach is taken. We report a case of a young adult with invasion of the tumor into the anterior cranial fossa. MRI aided in the assessment of the intracranial tumor spread and allowed for a direct visualization of the meningeal membranes. The signal characteristics of the tumor and the adjacent tissue in unenhanced and postcontrast MRI is discussed. MRI was clearly superior to CT and indicative for the choice of treatment.

Water-suppressed proton magnetic resonance spectroscopy which has recently shown diagnostic potential in human stroke victims was performed in two patients who had suffered a hemispheric transient ischemic attack. Localized spectra were targeted from routine MR images. In one patient lactate could be observed 8 weeks after a transient ischemic attack. Lactate concentration was low compared with that of a patient who had suffered acute stroke. The other TIA patient did not show evidence of lactate production. Although these observations are preliminary, we demonstrated that localized in vivo proton spectroscopy can detect persistent biochemical alterations after transient ischemic attacks. We suggest that non-invasive in vivo proton spectroscopy will become a useful method in diagnosis and management of TIA in the future.