Publications by authors named "Christian Vollmar"

74 Publications

Uncrossed corticospinal tract in health and genetic disorders: Review, case report and clinical implications.

Eur J Neurol 2021 May 5. Epub 2021 May 5.

University Hospital of the LMU Munich, Department of Neurology, Marchioninistr. 15, 81377, Munich, Germany.

Background: Crossing pathologies of the corticospinal tract (CST) are rare and often associated with genetic disorders. However, they can be present in healthy humans and lead to ipsilateral motor deficits when a lesion to motor areas occurs. Here we review historical and current literature of CST crossing pathologies and present a rare case of asymmetric crossing of the CST.

Methods: Description of the case and systematic review of the literature based on the PRISMA guidelines. The PubMed database was searched for peer-reviewed articles in English since 1950. All articles on ipsilateral stroke, uncrossed CST, and associated neurologic disorders were screened. Furthermore, a literature review between the years 1850 and 1980 including articles in other languages, books, opinions, and case studies was conducted.

Results: Only few descriptions of CST crossing pathologies exist in healthy humans, while they seem to be more common in genetic disorders like horizontal gaze palsy with progressive scoliosis or congenital mirror movements. Our patient presented with aphasia and left-sided hemiparesis. CT-scan revealed a perfusion deficit in the left middle cerebral artery territory, which was confirmed by diffusion-weighted MRI, so that thrombolysis was administered. Diffusion tensor imaging with fibre tracking revealed an asymmetric CST crossing.

Conclusion: The knowledge of CST crossing pathologies is essential if a motor deficit occurs ipsilateral to the lesion side. An ipsilateral deficit should not lead to exclusion or delay of therapeutic options in patients with suspected stroke. Here, a combined evaluation of CT perfusion imaging and MRI diffusion imaging may be of advantage.
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http://dx.doi.org/10.1111/ene.14897DOI Listing
May 2021

What have we learned from 8 years of deep brain stimulation of the anterior thalamic nucleus? Experiences and insights of a single center.

J Neurosurg 2020 Oct 30:1-10. Epub 2020 Oct 30.

1Epilepsy Center, Department of Neurology; and Departments of.

Objective: In the absence of a standard or guideline for the treatment of epilepsy patients with deep brain stimulation (DBS) of the anterior nucleus of the thalamus (ANT), systematic single-center investigations are essential to establish effective approaches. Here, the authors report on the long-term results of one of the largest single-center ANT DBS cohorts.

Methods: The outcome data of 23 consecutive patients with transventricularly implanted electrodes were retrospectively analyzed with regard to adverse events, lead placement, stimulation-related side effects, and changes in seizure frequency. Depression and quality-of-life scores were collected in a subgroup of 9 patients.

Results: All but 2 patients initially underwent bilateral implantation, and 84.4% of all DBS leads were successfully located within the ANT. The mean follow-up time was 46.57 ± 23.20 months. A seizure reduction > 50% was documented in 73.9% of patients, and 34.6% achieved an Engel class I outcome. In 3 patients, clinical response was achieved by switching the electrode contact or changing from the monopolar to bipolar stimulation mode. Unilateral implantation seemed ineffective, whereas bilateral stimulation with successful ANT implantation only on one side led to a clinical response. Double stimulation with additional vagus nerve stimulation was safe. Changes in cycling mode or stimulation amplitude influenced therapy tolerability and, only to a lesser extent, seizure frequency. Side effects were rare and typically vanished by lowering the stimulation amplitude or changing the active electrode contact. Furthermore, depression and aspects of quality of life significantly improved with ANT DBS treatment.

Conclusions: The transventricular approach as well as double stimulation proved safe. The anteroventral ANT appeared to be the most efficacious stimulation site. This systematic investigation with reluctant medication changes allowed for the development of a better idea of the association between parameter changes and outcome in ANT DBS patients, but larger samples are still needed to assess the potential of bipolar stimulation and distinct cycling frequencies. Furthermore, more multifaceted and objective assessments of treatment outcome are needed to fully assess the effects of ANT DBS treatment.
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http://dx.doi.org/10.3171/2020.6.JNS20695DOI Listing
October 2020

Hemispheric differences in the duration of focal onset seizures.

Acta Neurol Scand 2021 Mar 21;143(3):248-255. Epub 2020 Oct 21.

Epilepsy Center, Department of Neurology, University Hospital, LMU Munich, Munich, Germany.

Objective: To assess hemispheric differences in the duration of focal onset seizures and its association with clinical and demographic factors.

Methods: A retrospective analysis was performed on adult patients with drug-resistant unifocal epilepsy, who underwent intracranial EEG recording between 01/2006 and 06/2016. Seizure duration was determined based on the subdural and/or stereo-EEG (sEEG) recordings. Hemispheric differences in seizure duration were statistically evaluated with regard to clinical and demographic data.

Results: In total, 69 patients and 654 focal onset seizures were included. The duration of seizures with left-hemispheric onset (n = 297) was by trend longer (91.88 ± 93.92 s) than of right-hemispheric seizures (n = 357; 71.03 ± 68.53 s; p = .193). Significant hemispheric differences in seizures duration were found in temporal lobe seizures (n = 225; p = .013), especially those with automotor manifestation (n = 156; p = .045). A prolonged duration was also found for left-hemispheric onset seizures with secondary generalized commencing during waking state (n = 225; p = .034), but not during sleep. A similar hemispheric difference in seizure duration was found in female patients (p = .040), but not in men.

Conclusions: Hemispheric differences in seizure duration were revealed with significantly longer durations in case of left-hemispheric seizure onset. The observed differences in seizure duration might result from brain asymmetry and add new aspects to the understanding of seizure propagation and termination.
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http://dx.doi.org/10.1111/ane.13356DOI Listing
March 2021

Motor hyperactivation during cognitive tasks: An endophenotype of juvenile myoclonic epilepsy.

Epilepsia 2020 07 25;61(7):1438-1452. Epub 2020 Jun 25.

Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, London, UK.

Objective: Juvenile myoclonic epilepsy (JME) is the most common genetic generalized epilepsy syndrome. Myoclonus may relate to motor system hyperexcitability and can be provoked by cognitive activities. To aid genetic mapping in complex neuropsychiatric disorders, recent research has utilized imaging intermediate phenotypes (endophenotypes). Here, we aimed to (a) characterize activation profiles of the motor system during different cognitive tasks in patients with JME and their unaffected siblings, and (b) validate those as endophenotypes of JME.

Methods: This prospective cross-sectional investigation included 32 patients with JME, 12 unaffected siblings, and 26 controls, comparable for age, sex, handedness, language laterality, neuropsychological performance, and anxiety and depression scores. We investigated patterns of motor system activation during episodic memory encoding and verb generation functional magnetic resonance imaging (fMRI) tasks.

Results: During both tasks, patients and unaffected siblings showed increased activation of motor system areas compared to controls. Effects were more prominent during memory encoding, which entailed hand motion via joystick responses. Subgroup analyses identified stronger activation of the motor cortex in JME patients with ongoing seizures compared to seizure-free patients. Receiver-operating characteristic curves, based on measures of motor activation, accurately discriminated both patients with JME and their siblings from healthy controls (area under the curve: 0.75 and 0.77, for JME and a combined patient-sibling group against controls, respectively; P < .005).

Significance: Motor system hyperactivation represents a cognitive, domain-independent endophenotype of JME. We propose measures of motor system activation as quantitative traits for future genetic imaging studies in this syndrome.
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http://dx.doi.org/10.1111/epi.16575DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7681252PMC
July 2020

Who seizes longest? Impact of clinical and demographic factors.

Epilepsia 2020 07 21;61(7):1376-1385. Epub 2020 Jun 21.

Department of Neurology, Epilepsy Center, University Hospital, Ludwig Maximilian University of Munich, Munich, Germany.

Objective: To investigate the impact of clinical and demographic parameters on the duration of focal onset seizures with and without secondary generalization using precise duration measurements from intracranial electroencephalographic (iEEG) recordings.

Methods: Patients with unifocal epilepsy syndromes and iEEG recording were retrospectively identified from the database of the local epilepsy center (2006-2016). Seizure duration was defined as time difference of iEEG seizure pattern onset and cessation. The seizure semiology was classified based on video recordings. Clinical and demographic data were extracted from patient reports.

Results: In total, 69 adults were included, and 654 focal onset seizures were analyzed. Focal to bilateral tonic-clonic seizures (FBTCSs; 98/654) were significantly longer than focal seizures (FSs) without generalization (FS-BTCs; 556/654, P < .001), and most FSs (545/654, 83.3%) terminated within 2 minutes. The duration of FSs was prolonged with increasing age of the patients (P = .003) and was significantly shortened (P < .001) by evolution into an FBTCS. FBTCSs with lateralizing semiologies like version (P = .015) and sign of four (P = .043) were associated with longer bilateral tonic-clonic manifestations. Furthermore, FBTCSs with preceding aura, frontal origin, or onset during sleep were by trend shorter. Age (P < .001) and disease duration (P = .028) were essential for prediction of FS-BTC duration, whereas the vigilance state (P = .085) was the main prediction factor for the duration of FBTCSs.

Significance: The identified modifiers of seizure duration are of great relevance for clinical risk evaluation, especially in the aging epilepsy patient suffering from temporal lobe epilepsy with secondary generalized seizures.
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http://dx.doi.org/10.1111/epi.16577DOI Listing
July 2020

Congruence and Discrepancy of Interictal and Ictal EEG With MRI Lesions in Pediatric Epilepsies.

Clin EEG Neurosci 2020 Nov 18;51(6):412-419. Epub 2020 May 18.

Ludwig Maximilians University (LMU) Munich, Epilepsy Center, Munich, Germany.

. To evaluate the congruence or discrepancy of the localization of magnetic resonance imaging (MRI) lesions with interictal epileptiform discharges (IEDs) or epileptic seizure patterns (ESPs) in surface EEG in lesional pediatric epilepsy patients. . We retrospectively analyzed presurgical MRI and video-EEG monitoring findings of patients up to age 18 years. Localization of MRI lesions were compared with ictal and interictal noninvasive EEG findings of patients with frontal, temporal, parietal, or occipital lesions. . A total of 71 patients were included. Localization of ESPs showed better congruence with MRI in patients with frontal lesions (n = 21, 77.5%) than in patients with temporal lesions (n = 24; 40.7%) ( = .009). No significant IED distribution differences between MRI localizations could be found. . MRI lesions and EEG findings are rarely fully congruent. Congruence of MRI lesions and ESPs was highest in children with frontal lesions. This is in contrast to adults, in whom temporal lesions showed the highest congruency with the EEG localization of ESP. Lesional pediatric patients should be acknowledged as surgical candidates despite incongruent findings of interictal and ictal surface EEG.
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http://dx.doi.org/10.1177/1550059420921712DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7457449PMC
November 2020

Changes of brain DTI in healthy human subjects after 520 days isolation and confinement on a simulated mission to Mars.

Life Sci Space Res (Amst) 2020 Feb 15;24:83-90. Epub 2019 Oct 15.

Department of Anaesthesiology & Laboratory of Translational Research "Stress and Immunity" at the Department of Anaesthesiology, Hospital of the University of Munich (LMU), Marchioninstraße 15, 81377 München, Munich, Germany. Electronic address:

Introduction: Long-term confinement is known to be a stressful experience with multiple psycho-physiological effects. In the MARS500 project, a real-time simulation of a space-flight to Mars conducted in a hermetically isolated habitat, effects of long-term confinement could be investigated in a unique manner. The aim of this study was to evaluate effects of long-term-confinement on brain cytoarchitecture.

Material & Methods: The participants of the MARS500 project underwent 3T-MR imaging including a dedicated DTI-sequence before the isolation, right after ending of confinement and 6 months after the experiment. Voxelwise statistical analysis of the DTI data was carried out using tract-based-spatial statistics, comparing an age-matched control group.

Results: At all three sessions, significant lower fractional anisotropy (FA) than in controls was found in the anterior parts of the callosal body of the participants. Furthermore, after ending of confinement a wide-spread FA reduction could be seen in the right hemisphere culminating in the temporo-parietal-junction-zone. All these areas with decreased FA predominantly showed an elevated radial diffusivity and mean diffusivity while axial diffusivity was less correlated.

Discussion: Long-term confinement does have measurable effects on the microstructure of the brain white matter. We assume effects of sensory deprivation to account for the regional FA reductions seen in the right TPJ. The differences in the Corpus callosum were interpreted as due to preliminary conditions, e.g. personality traits or training effects. FA and radial diffusivity were the predominant DTI parameters with significant changes, suggesting underlying processes of myelin plasticity.
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http://dx.doi.org/10.1016/j.lssr.2019.09.004DOI Listing
February 2020

Developmental MRI markers cosegregate juvenile patients with myoclonic epilepsy and their healthy siblings.

Neurology 2019 09 29;93(13):e1272-e1280. Epub 2019 Aug 29.

From the Neuroimaging of Epilepsy Laboratory (B.W., S.-J.H., B.C.B., F.F., N.B., A.B.), McConnell Brain Imaging Center, Montreal Neurological Institute, McGill University, Montreal; Department of Clinical and Experimental Epilepsy (B.W., C.V., M.J.K.), UCL Institute of Neurology, London, UK; Epilepsy Center, Department of Neurology (C.V.), Klinikum Großhadern, University of Munich, Germany; and Multimodal Imaging and Connectome Analysis Lab (B.C.B.), Montreal Neurological Institute and Hospital, McGill University, Montreal, Canada.

Objective: MRI studies of genetic generalized epilepsies have mainly described group-level changes between patients and healthy controls. To determine the endophenotypic potential of structural MRI in juvenile myoclonic epilepsy (JME), we examined MRI-based cortical morphologic markers in patients and their healthy siblings.

Methods: In this prospective, cross-sectional study, we obtained 3T MRI in patients with JME, siblings, and controls. We mapped sulco-gyral complexity and surface area, morphologic markers of brain development, and cortical thickness. Furthermore, we calculated mean geodesic distance, a surrogate marker of cortico-cortical connectivity.

Results: Compared to controls, patients and siblings showed increased folding complexity and surface area in prefrontal and cingulate cortices. In these regions, they also displayed abnormally increased geodesic distance, suggesting network isolation and decreased efficiency, with strongest effects for limbic, fronto-parietal, and dorsal-attention networks. In areas of findings overlap, we observed strong patient-sibling correlations. Conversely, neocortical thinning was present in patients only and related to disease duration. Patients showed subtle impairment in mental flexibility, a frontal lobe function test, as well as deficits in naming and design learning. Siblings' performance fell between patients and controls.

Conclusion: MRI markers of brain development and connectivity are likely heritable and may thus serve as endophenotypes. The topography of morphologic anomalies and their abnormal structural network integration likely explains cognitive impairments in patients with JME and their siblings. By contrast, cortical atrophy likely represents a marker of disease.
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http://dx.doi.org/10.1212/WNL.0000000000008173DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7011863PMC
September 2019

Abnormal hippocampal structure and function in juvenile myoclonic epilepsy and unaffected siblings.

Brain 2019 09;142(9):2670-2687

Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, Queen Square, London, UK.

Juvenile myoclonic epilepsy is the most common genetic generalized epilepsy syndrome, characterized by a complex polygenetic aetiology. Structural and functional MRI studies demonstrated mesial or lateral frontal cortical derangements and impaired fronto-cortico-subcortical connectivity in patients and their unaffected siblings. The presence of hippocampal abnormalities and associated memory deficits is controversial, and functional MRI studies in juvenile myoclonic epilepsy have not tested hippocampal activation. In this observational study, we implemented multi-modal MRI and neuropsychological data to investigate hippocampal structure and function in 37 patients with juvenile myoclonic epilepsy, 16 unaffected siblings and 20 healthy controls, comparable for age, gender, handedness and hemispheric dominance as assessed with language laterality indices. Automated hippocampal volumetry was complemented by validated qualitative and quantitative morphological criteria to detect hippocampal malrotation, assumed to represent a neurodevelopmental marker. Neuropsychological measures of verbal and visuo-spatial learning and an event-related verbal and visual memory functional MRI paradigm addressed mesiotemporal function. We detected a reduction of mean left hippocampal volume in patients and their siblings compared with controls (P < 0.01). Unilateral or bilateral hippocampal malrotation was identified in 51% of patients and 50% of siblings, against 15% of controls (P < 0.05). For bilateral hippocampi, quantitative markers of verticalization had significantly larger values in patients and siblings compared with controls (P < 0.05). In the patient subgroup, there was no relationship between structural measures and age at disease onset or degree of seizure control. No overt impairment of verbal and visual memory was identified with neuropsychological tests. Functional mapping highlighted atypical patterns of hippocampal activation, pointing to abnormal recruitment during verbal encoding in patients and their siblings [P < 0.05, familywise error (FWE)-corrected]. Subgroup analyses indicated distinct profiles of hypoactivation along the hippocampal long axis in juvenile myoclonic epilepsy patients with and without malrotation; patients with malrotation also exhibited reduced frontal recruitment for verbal memory, and more pronounced left posterior hippocampal involvement for visual memory. Linear models across the entire study cohort indicated significant associations between morphological markers of hippocampal positioning and hippocampal activation for verbal items (all P < 0.05, FWE-corrected). We demonstrate abnormalities of hippocampal volume, shape and positioning in patients with juvenile myoclonic epilepsy and their siblings, which are associated with reorganization of function and imply an underlying neurodevelopmental mechanism with expression during the prenatal stage. Co-segregation of abnormal hippocampal morphology in patients and their siblings is suggestive of a genetic imaging phenotype, independent of disease activity, and can be construed as a novel endophenotype of juvenile myoclonic epilepsy.
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http://dx.doi.org/10.1093/brain/awz215DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6776114PMC
September 2019

10Kin1day: A Bottom-Up Neuroimaging Initiative.

Front Neurol 2019 9;10:425. Epub 2019 May 9.

Department of Psychiatry, Stellenbosch University, Cape Town, South Africa.

We organized 10Kin1day, a pop-up scientific event with the goal to bring together neuroimaging groups from around the world to jointly analyze 10,000+ existing MRI connectivity datasets during a 3-day workshop. In this report, we describe the motivation and principles of 10Kin1day, together with a public release of 8,000+ MRI connectome maps of the human brain.
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http://dx.doi.org/10.3389/fneur.2019.00425DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6524614PMC
May 2019

Outcome after individualized stereoelectroencephalography (sEEG) implantation and navigated resection in patients with lesional and non-lesional focal epilepsy.

J Neurol 2019 Apr 30;266(4):910-920. Epub 2019 Jan 30.

Department of Neurosurgery, University Hospital of Munich, Ludwig-Maximilians-University, Marchioninistr. 15, 81377, Munich, Germany.

Background: Refined localization of the epileptogenic zone (EZ) in patients with pharmacoresistant focal epilepsy proceeding to resective surgery might improve postoperative outcome. We here report seizure outcome after stereo EEG (sEEG) evaluation with individually planned stereotactically implanted depth electrodes and subsequent tailored resection.

Methods: A cohort of consecutive patients with pharmacoresistant focal epilepsy, evaluated with a non-invasive evaluation protocol and invasive monitoring with personalized, stereotactically implanted depth electrodes for sEEG was analyzed. Co-registration of post-implantation CT scan to presurgical MRI data was used for 3D reconstructions of the patients' brain surface and mapping of neurophysiology data. Individual multimodal 3D maps of the EZ were used to guide subsequent tailored resections. The outcome was rated according to the Engel classification.

Results: Out of 914 patients who underwent non-invasive presurgical evaluation, 85 underwent sEEG, and 70 were included in the outcome analysis. Median follow-up was 31.5 months. Seizure-free outcome (Engel class I A-C, ILAE class 1-2) was achieved in 83% of the study cohort. Patients exhibiting lesional and non-lesional (n = 42, 86% vs. n = 28, 79%), temporal and extratemporal (n = 45, 80% vs. n = 25, 84%), and right- and left-hemispheric epilepsy (n = 44, 82% vs. n = 26, 85%) did similarly well. This remains also true for those with an EZ adjacent to or distant from eloquent cortex (n = 21, 86% vs. n = 49, 82%). Surgical outcome was independent of resected tissue volume.

Conclusion: Favourable post-surgical outcome can be achieved in patients with resistant focal epilepsy, using individualized sEEG evaluation and tailored navigated resection, even in patients with non-lesional or extratemporal focal epilepsy.
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http://dx.doi.org/10.1007/s00415-019-09213-3DOI Listing
April 2019

Acute frontal eye field infarction: A topodiagnostic challenge.

Neurology 2019 01 28;92(4):193-195. Epub 2018 Dec 28.

From the Institute of Clinical Neuroimmunology, University Hospital and Biomedical Center (F.S.T.), and Department of Neurology (C.K., C.V., O.K., A.D.) and German Center for Vertigo and Balance Disorders (S.B., O.K.), University Hospital, Ludwig-Maximilians-Universität München, Munich, Germany; and Institute of Neurology (C.K.), University College London, Queen Square, UK.

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http://dx.doi.org/10.1212/WNL.0000000000006813DOI Listing
January 2019

Ictal SPECT reveals different epileptogenic zones in frontal lobe epilepsy.

Epileptic Disord 2018 Oct;20(5):447-450

Epilepsy Center, Department of Neurology, University of Munich, Munich, Germany.

We report a patient with frontal lobe epilepsy due to a right frontal astrocytoma (WHO Grade III) in whom two ictal SPECTs (single photon emission tomography) were performed during two seizures with different semiology and different EEG seizure patterns. Subtraction of ictal and interictal SPECT showed right lateral frontal hyperperfusion during a left face clonic seizure, and right mesial fronto-polar hyperperfusion during a subclinical seizure. This report demonstrates that ictal SPECT may reflect different seizure semiology from the frontal lobe of the same individual and that simultaneous EEG is indispensable for the correct interpretation of SPECT in epilepsy.
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http://dx.doi.org/10.1684/epd.2018.0991DOI Listing
October 2018

Stimulation-induced ictal vocalisation of left frontal lobe origin.

Epileptic Disord 2018 Oct;20(5):418-422

Epilepsy Center, Department of Neurology, University of Munich, Munich, Germany.

Pure ictal non-speech vocalisation occurs in frontal and temporal lobe epilepsies. Electrical stimulation of supplementary motor areas is reported to evoke vocalisation in selected patients. Here, we report a patient with focal epilepsy of the left anterior insula who had isolated monotonous vocalisation elicited by electrical stimulation of the left superior frontal gyrus. Quantitative analysis of audio signals was performed and compared with a former patient with left frontal lobe epilepsy who had pure ictal vocalisation. Both patients showed a comparable reduction in frequency variation indicating a monotonous voice. [Published with video sequences on www.epilepticdisorders.com].
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http://dx.doi.org/10.1684/epd.2018.0990DOI Listing
October 2018

Unilateral temporal interictal epileptiform discharges correctly predict the epileptogenic zone in lesional temporal lobe epilepsy.

Epilepsia 2018 08 15;59(8):1577-1582. Epub 2018 Jul 15.

Epilepsy Center, Department of Neurology, University Hospital, Ludwig-Maximilians-University, Munich, Germany.

Objective: To evaluate the necessity of recording ictal electroencephalography (EEG) in patients with temporal lobe epilepsy (TLE) considered for resective surgery who have unilateral temporal interictal epileptiform discharges (IEDs) and concordant ipsitemporal magnetic resonance imaging (MRI) pathology. To calculate the necessary number of recorded EEG seizure patterns (ESPs) to achieve adequate lateralization probability.

Methods: In a retrospective analysis, the localization and lateralization of interictal and ictal EEG of 304 patients with lesional TLE were analyzed. The probability of further contralateral ESPs was calculated based on a total of 1967 recorded ESPs, using Bayes' theorem.

Results: Two hundred seventy-one patients had unilateral TLE, and in 98% of them (265 of 271), IEDs were recorded during video-EEG monitoring. Purely unilateral temporal IEDs were present in 61% (166 of 271 patients). Ipsilateral temporal MRI pathology was found in 83% (138 of 166). Ictal EEG was concordant with the clinical side of TLE in 99% (136 of 138) of these patients. Two patients had discordant ictal EEG with both ipsilateral and contralateral ESPs. Epilepsy surgery with resection in the lesioned temporal lobe was still performed, and both patients remain seizure-free. Probability calculations demonstrate that at least 6 recorded unilateral ESPs result in a >95% probability for a concordance of >0.9 of any further ESPs.

Significance: The combination of purely unilateral temporal IED with ipsitemporal MRI pathology is sufficient to identify the epileptogenic zone, and the recording of ictal ESP did not add any surgically relevant information in these 138 patients. Rarely, discordant ESPs might be recorded, but the surgical outcome remains excellent after surgery on the lesioned side.
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http://dx.doi.org/10.1111/epi.14514DOI Listing
August 2018

Effects of carbamazepine and lamotrigine on functional magnetic resonance imaging cognitive networks.

Epilepsia 2018 07 13;59(7):1362-1371. Epub 2018 Jun 13.

Department of Clinical and Experimental Epilepsy, University College London Institute of Neurology, London, UK.

Objective: To investigate the effects of sodium channel-blocking antiepileptic drugs (AEDs) on functional magnetic resonance imaging (fMRI) language network activations in patients with focal epilepsy.

Methods: In a retrospective study, we identified patients who were treated at the time of language fMRI scanning with either carbamazepine (CBZ; n = 42) or lamotrigine (LTG; n = 42), but not another sodium channel-blocking AED. We propensity-matched 42 patients taking levetiracetam (LEV) as "patient-controls" and included further 42 age- and gender-matched healthy controls. After controlling for age, age at onset of epilepsy, gender, and antiepileptic comedications, we compared verbal fluency fMRI activations between groups and out-of-scanner psychometric measures of verbal fluency.

Results: Patients on CBZ performed less well on a verbal fluency tests than those taking LTG or LEV. Compared to either LEV-treated patients or controls, patients taking CBZ showed decreased activations in left inferior frontal gyrus and patients on LTG showed abnormal deactivations in frontal and parietal default mode areas. All patient groups showed fewer activations in the putamen bilaterally compared to controls. In a post hoc analysis, out-of-scanner fluency scores correlated positively with left putamen activation.

Significance: Our study provides evidence of AED effects on the functional neuroanatomy of language, which might explain subtle language deficits in patients taking otherwise well-tolerated sodium channel-blocking agents. Patients on CBZ showed dysfunctional frontal activation and more pronounced impairment of performance than patients taking LTG, which was associated only with failure to deactivate task-negative networks. As previously shown for working memory, LEV treatment did not affect functional language networks.
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http://dx.doi.org/10.1111/epi.14448DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6216427PMC
July 2018

Multimodal Imaging in Extratemporal Epilepsy Surgery.

Cureus 2018 Mar 18;10(3):e2338. Epub 2018 Mar 18.

Epilepsy Center, Dept. of Neurology, University of Munich Hospital, Ludwig-Maximilians-University Munich.

Neuroimaging is crucial for the evaluation of patients considered for resective epilepsy surgery. Multimodal image fusion is a new tool to integrate all available localizing information on the individual epileptogenic network in a three-dimensional (3D) manner to plan invasive EEG recordings and delineate the epileptogenic zone from the eloquent cortex for the neurosurgical planning of a tailored resection. Here, we illustrate the multimodal fusion of images from different modalities in a patient with medically intractable non-lesional frontal lobe epilepsy who underwent partial frontal lobe resection, rendering him seizure-free.
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http://dx.doi.org/10.7759/cureus.2338DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5959727PMC
March 2018

NeuroKinect 3.0: Multi-Bed 3Dvideo-EEG System for Epilepsy Clinical Motion Monitoring.

Stud Health Technol Inform 2018 ;247:46-50

Epilepsy Center, Department of Neurology, University of Munich, Munich, Germany.

Epilepsy diagnosis is typically performed through 2Dvideo-EEG monitoring, relying on the viewer's subjective interpretation of the patient's movements of interest. Several attempts at quantifying seizure movements have been performed in the past using 2D marker-based approaches, which have several drawbacks for the clinical routine (e.g. occlusions, lack of precision, and discomfort for the patient). These drawbacks are overcome with a 3D markerless approach. Recently, we published the development of a single-bed 3Dvideo-EEG system using a single RGB-D camera (Kinect v1). In this contribution, we describe how we expanded the previous single-bed system to a multi-bed departmental one that has been managing 6.61 Terabytes per day since March 2016. Our unique dataset collected so far includes 2.13 Terabytes of multimedia data, corresponding to 278 3Dvideo-EEG seizures from 111 patients. To the best of the authors' knowledge, this system is unique and has the potential of being spread to multiple EMUs around the world for the benefit of a greater number of patients.
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June 2018

Atrophy in the Thalamus But Not Cerebellum Is Specific for FTD and ALS Patients - An Atlas-Based Volumetric MRI Study.

Front Aging Neurosci 2018 15;10:45. Epub 2018 Mar 15.

Department of Neurology, Ludwig Maximilians Universität München, Munich, Germany.

The neuropathology of patients with frontotemporal dementia (FTD) or amyotrophic lateral sclerosis (ALS) due to a mutation is characterized by two distinct types of characteristic protein depositions containing either TDP-43 or so-called dipeptide repeat proteins that extend beyond frontal and temporal regions. Thalamus and cerebellum seem to be preferentially affected by the dipeptide repeat pathology unique to mutation carriers. This study aimed to determine if mutation carriers showed an enhanced degree of thalamic and cerebellar atrophy compared to sporadic patients or healthy controls. Atlas-based volumetry was performed in 13 affected FTD, ALS and FTD/ALS patients, 45 sporadic FTD and FTD/ALS patients and 19 healthy controls. Volumes and laterality indices showing significant differences between mutation carriers and sporadic patients were subjected to binary logistic regression to determine the best predictor of mutation carrier status. Compared to sporadic patients, mutation carriers showed a significant volume reduction of the thalamus, which was most striking in the occipital, temporal and prefrontal subregion of the thalamus. Disease severity measured by mini mental status examination (MMSE) and FTD modified Clinical Dementia Rating Scale Sum of Boxes (FTD-CDR-SOB) significantly correlated with volume reduction in the aforementioned thalamic subregions. No significant atrophy of cerebellar regions could be detected. A logistic regression model using the volume of the prefrontal and the laterality index of the occipital subregion of the thalamus as predictor variables resulted in an area under the curve (AUC) of 0.88 while a model using overall thalamic volume still resulted in an AUC of 0.82. Our data show that thalamic atrophy in mutation carriers goes beyond the expected atrophy in the prefrontal and temporal subregion and is in good agreement with the cortical atrophy pattern described in mutation carriers, indicating a retrograde degeneration of functionally connected regions. Clinical relevance of the detected thalamic atrophy is illustrated by a correlation with disease severity. Furthermore, the findings suggest MRI volumetry of the thalamus to be of high predictive value in differentiating mutation carriers from patients with sporadic FTD.
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http://dx.doi.org/10.3389/fnagi.2018.00045DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5863593PMC
March 2018

Brain diffusion tensor imaging changes in cerebrotendinous xanthomatosis reversed with treatment.

J Neurol 2018 Feb 19;265(2):388-393. Epub 2017 Dec 19.

Department of Neurology with Friedrich-Baur Institute, University Hospital of the Ludwig-Maximilians-Universität München, Munich, Germany.

Cerebrotendinous xanthomatosis (CTX, MIM 213700) is a rare autosomal recessive lipid storage disorder caused by CYP27A1 mutations. Treatment with chenodeoxycholic acid (CDCA) may slow the progression of the disease and reverse some symptoms in a proportion of patients. In a non-consanguineous Caucasian family, two siblings with CTX were evaluated before treatment and prospectively followed-up every 6 months after starting CDCA therapy, using systematic clinical examination, neuropsychological tests, laboratory tests, electroencephalography (EEG) and brain MRI, diffusion tensor imaging (DTI) and tractography. A 30-year-old patient and her 27-year-old brother were referred for progressive spastic paraparesis. Both had epilepsy, learning difficulties, chronic diarrhoea and juvenile-onset cataracts. CTX was diagnosed by increased cholestanol levels and compound heterozygosity for CYP27A1 mutations. Therapy with CDCA led to resolution of chronic diarrhoea, normalisation of serum cholestanol and EEG, and a progressive improvement in gait, cognition and seizure control. Before treatment, conventional brain MRI showed no CTX-related abnormalities for the proband and no cerebellar abnormalities for the brother, while DTI showed reduced fractional anisotropy (FA) and tract-density in the cerebellum and widespread cerebral reductions of FA in both patients, compared to a group of 35 healthy controls. Repeated DTI after starting therapy showed progressive increases of cerebellar tract density and of cerebral FA. In patients with CTX, therapy with CDCA may lead to significant clinical improvement, with normalisation of biochemical and electrophysiological biomarkers. DTI and tractography may detect changes when the conventional MRI is unremarkable and may provide potential neuroimaging biomarkers for monitoring treatment response in CTX, while the conventional MRI remains unchanged.
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http://dx.doi.org/10.1007/s00415-017-8711-9DOI Listing
February 2018

Seizure-associated aphasia has good lateralizing but poor localizing significance.

Epilepsia 2017 09 4;58(9):1551-1555. Epub 2017 Jul 4.

Department of Neurology, Epilepsy Center, University of Munich, Munich, Germany.

Objective: To investigate the occurrence of ictal and postictal aphasia in different focal epilepsy syndromes.

Methods: We retrospectively analyzed the video-electroencephalographic monitoring data of 1,118 patients with focal epilepsy for seizure-associated aphasia (SAA). Statistical analysis included chi-square analysis and Fisher's exact test.

Results: We identified 102 of 1,118 patients (9.1%) in whom ictal or postictal aphasia (SAA) was part of their recorded seizures (n = 59 of 102; 57.8%) or who reported aphasia by history (n = 43; 42.2% only reported aphasia by history). Postictal aphasia was present in 18 patients (30.5%). Six of the 59 patients had both ictal and postictal aphasia (10.2%). SAA occurred either with left hemisphere seizure onset or with seizures spreading from the right to the left hemisphere. SAA was most common in patients with parieto-occipital epilepsy (10.9%; five of 46 patients), followed by patients with temporal (6.7%; 28 of 420 patients), focal (not further localized; 4.8%; 22 of 462 patients), and frontal epilepsy (2.1%; four of 190 patients; p = 0.04). SAA was more common in parieto-occipital epilepsy than in frontal epilepsy (p = 0.02). In contrast, there was no significant difference in SAA between temporal and parieto-occipital epilepsy (p = 0.36).

Significance: SAA has a high lateralizing but limited localizing value, as it often reflects spread of epileptic activity into speech-harboring brain regions.
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http://dx.doi.org/10.1111/epi.13835DOI Listing
September 2017

A novel portable, low-cost kinect-based system for motion analysis in neurological diseases.

Annu Int Conf IEEE Eng Med Biol Soc 2016 Aug;2016:2339-2342

Many neurological diseases, such as Parkinson's disease and epilepsy, can significantly impair the motor function of the patients, often leading to a dramatic loss of their quality of life. Human motion analysis is regarded as fundamental towards an early diagnosis and enhanced follow-up in this type of diseases. In this contribution, we present NeuroKinect, a novel system designed for motion analysis in neurological diseases. This system includes an RGB-D camera (Microsoft Kinect) and two integrated software applications, KiT (KinecTracker) and KiMA (Kinect Motion Analyzer). The applications enable the preview, acquisition, review and management of data provided by the sensor, which are then used for motion analysis of relevant events. NeuroKinect is a portable, low-cost and markerless solution that is suitable for use in the clinical environment. Furthermore, it is able to provide quantitative support to the clinical assessment of different neurological diseases with movement impairments, as demonstrated by its usage in two different clinical routine scenarios: gait analysis in Parkinson's disease and seizure semiology analysis in epilepsy.
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http://dx.doi.org/10.1109/EMBC.2016.7591199DOI Listing
August 2016

The role of the pallidothalamic fibre tracts in deep brain stimulation for dystonia: A diffusion MRI tractography study.

Hum Brain Mapp 2017 03 16;38(3):1224-1232. Epub 2016 Nov 16.

Department of Computer Science, Sherbrooke Connectivity Imaging Lab (SCIL), Computer Science department, Université de Sherbrooke, Sherbrooke, Québec, Canada.

Background: Deep Brain Stimulation (DBS) of the Globus pallidus internus (GPi) is gold standard treatment in medically refractory dystonia. Recent evidence indicates that stimulation effects are also due to axonal modulation and affection of a fibre network. For the GPi, the pallidothalamic tracts are known to be the major motor efferent pathways. The aim of this study is to explore the anatomic vicinity of these tracts and DBS electrodes in dystonia applying diffusion tractography.

Methods: Diffusion MRI was acquired in ten patients presenting for DBS for dystonia. We applied both a conventionally used probabilistic tractography algorithm (FSL) as well as a probabilistic streamline tracking approach, based on constrained spherical deconvolution and particle filtering with anatomic priors, to the datasets. DBS electrodes were coregistered to the diffusion datasets.

Results: We were able to delineate the pallidothalamic tracts in all patients. Using the streamline approach, we were able to distinguish between the two sub-components of the tracts, the ansa lenticularis and the fasciculus lenticularis. Clinically efficient DBS electrodes displayed a close anatomic vicinity pathway of the pallidothalamic tracts, and their course was consistent with previous tracer labelling studies. Although we present only anatomic data, we interpret these findings as evidence of the possible involvement of fibre tracts to the clinical effect in DBS. Electrophysiological intraoperative recordings would be needed to complement our findings. In the future, a clear and individual delineation of the pallidothalamic tracts could optimize the stereotactic process of optimal electrode localization. Hum Brain Mapp 38:1224-1232, 2017. © 2016 Wiley Periodicals, Inc.
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http://dx.doi.org/10.1002/hbm.23450DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6867131PMC
March 2017

A diffusion-based connectivity map of the GPi for optimised stereotactic targeting in DBS.

Neuroimage 2017 01 17;144(Pt A):83-91. Epub 2016 Sep 17.

Department of Neurology, Klinikum Grosshadern, University of Munich, Germany. Electronic address:

Background: The GPi (globus pallidus internus) is an important target nucleus for Deep Brain Stimulation (DBS) in medically refractory movement disorders, in particular dystonia and Parkinson's disease. Beneficial clinical outcome critically depends on precise electrode localization. Recent evidence indicates that not only neurons, but also axonal fibre tracts contribute to promoting the clinical effect. Thus, stereotactic planning should, in the future, also take the individual course of fibre tracts into account.

Objective: The aim of this project is to explore the GPi connectivity profile and provide a connectivity-based parcellation of the GPi.

Methods: Diffusion MRI sequences were performed in sixteen healthy, right-handed subjects. Connectivity-based parcellation of the GPi was performed applying two independent methods: 1) a hypothesis-driven, seed-to-target approach based on anatomic priors set as connectivity targets and 2) a purely data-driven approach based on k-means clustering of the GPi.

Results: Applying the hypothesis-driven approach, we obtained five major parcellation clusters, displaying connectivity to the prefrontal cortex, the brainstem, the GPe (globus pallidus externus), the putamen and the thalamus. Parcellation clusters obtained by both methods were similar in their connectivity profile. With the data-driven approach, we obtained three major parcellation clusters. Inter-individual variability was comparable with results obtained in thalamic parcellation.

Conclusion: The three parcellation clusters obtained by the purely data-driven method might reflect GPi subdivision into a sensorimotor, associative and limbic portion. Clinical and physiological studies indicate greatest clinical DBS benefit for electrodes placed in the postero-ventro-lateral GPi, the region displaying connectivity to the thalamus in our study and generally attributed to the sensorimotor system. Clinical studies relating DBS electrode positions to our GPi connectivity map would be needed to complement our findings.
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http://dx.doi.org/10.1016/j.neuroimage.2016.06.018DOI Listing
January 2017

Lateralization of cortical negative motor areas.

Clin Neurophysiol 2016 10 10;127(10):3314-21. Epub 2016 Aug 10.

Epilepsy Center, Department of Neurology, University of Munich, Germany. Electronic address:

Objective: The lateral and mesial aspects of the central and frontal cortex were studied by direct electrical stimulation of the cortex in epilepsy surgery candidates in order to determine the localization of unilateral and bilateral negative motor responses.

Methods: Results of electrical cortical stimulation were examined in epilepsy surgery candidates in whom invasive electrodes were implanted. The exact localization of subdural electrodes was defined by fusion of 3-dimensional reconstructed MRI and CT images in 13 patients and by analysis of plane skull X-rays and intraoperative visual localization of the electrodes in another 7 patients.

Results: Results of electrical stimulation of the cortex were evaluated in a total of 128 patients in whom invasive electrodes were implanted for planning resective epilepsy surgery. Twenty patients, in whom negative motor responses were obtained, were included in the study. Bilateral upper limb negative motor responses were more often elicited from stimulation of the mesial frontal cortex whereas stimulation of the lateral central cortex leads to contralateral upper limb negative motor responses (p<0.0001). Bilateral negative motor responses were exclusively found in the superior frontal gyrus whereas contralateral negative motor responses localized predominantly in the anterior part of the precentral gyrus (p<0.0001).

Conclusions: Exact localization using 3-D fusion methods revealed that negative motor areas are widely distributed throughout the precentral gyrus and the mesial fronto-central cortex showing functional differences with regard to unilateral and bilateral upper limb representation.

Significance: The lateral fronto-central negative motor area serves predominantly contralateral upper limb motor control whereas the mesial frontal negative motor area represents bilateral upper limb movement control.
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http://dx.doi.org/10.1016/j.clinph.2016.08.001DOI Listing
October 2016

Applied multimodal diagnostics in a case of presenile dementia.

BMC Neurol 2016 Aug 9;16:131. Epub 2016 Aug 9.

Department of Neurology, Ludwig-Maximilians University, Munich, Germany.

Background: Alzheimer's disease (AD) is the most common cause of dementia in the elderly. The possibility of disease-modifying strategies has evoked a need for early and accurate diagnosis. To improve the accuracy of the clinical diagnosis of AD, biomarkers like cerebrospinal fluid (CSF) and neuroimaging techniques like magnetic resonance imaging (MRI) and positron emission tomography (PET) have been incorporated into the diagnostic guidelines of AD.

Case Presentation: In this case report we outline in reference to one of our patients with presenile dementia the current approaches to the diagnosis of AD. The patient was a 59-year old woman presenting with progressive memory decline. CSF-Aβ42 was normal while P-tau was slightly increased. FDG-PET indicated a pattern typical for AD, amyloid-PET showed an extensive global amyloid load, and tau-PET depicted a pronounced hippocampal tracer accumulation. The MRI scan was rated as normal at routine diagnostics, however quantitative volumetric analysis revealed significant atrophy especially of the parietal lobe. The combination of biomarkers and neuroimaging techniques was therefore suggestive of an underlying AD pathology.

Conclusions: To enable early and accurate diagnosis of AD and thereby also patient recruitment for anti-tau or anti-β-amyloid therapeutic trials, a combination of biomarkers and neuroimaging techniques seems useful.
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http://dx.doi.org/10.1186/s12883-016-0647-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4977691PMC
August 2016

PET imaging in extratemporal epilepsy requires consideration of electroclinical findings.

Epilepsy Res 2016 09 31;125:72-6. Epub 2016 May 31.

Epilepsy Center, Department of Neurology, University of Munich, Munich, Germany. Electronic address:

Objective: The study aimed to assess the relevance of interictal temporal glucose hypometabolism in patients with extratemporal epilepsy (ETE) by analyzing its association with a seizure semiology suggestive for temporal seizure involvement and the presence of temporal interictal epileptiform discharges (IEDs).

Methods: We retrospectively reviewed the database of our epilepsy monitoring unit for patients with ETE, in whom long-term EEG-video-monitoring and [(18)F] fluorodeoxyglucose positron emission tomography (FDG-PET) had been performed. The localization of IEDs and the glucose hypometabolism were compared.

Results: Almost half (46%) of the 63 ETE patients had IEDs localized in the temporal lobe. Most patients (87.5%; 7/8) with temporal IEDs and an ipsitemporal hypometabolism showed seizure semiology suggestive of temporal or limbic system involvement in contrast to only 31.0% (9/29, p=0.01) in patients without temporal IEDs nor temporal hypometabolism. Those patients also showed an ictal seizure pattern spread into the ipsitemporal lobe, compared with 75.9% (22/29, n.s.) in patients without temporal IEDs nor temporal hypometabolism. Both, extratemporal (ipsilateral in 82.1%; 23/28 patients) and temporal (ipsilateral in 78.6%; 11/14 patients) hypometabolism significantly (p<0.05) lateralized to the epileptogenic hemisphere.

Conclusion: The common temporal glucose hypometabolism in ETE patients reflects a remote epileptic dysfunction arising from extratemporal epileptogenic zones. Thus, interpretation of interictal FDG-PET results requires consideration of EEG results and seizure semiology to avoid false localization particularly in non-lesional epilepsy.
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http://dx.doi.org/10.1016/j.eplepsyres.2016.05.010DOI Listing
September 2016

PAX6, brain structure and function in human adults: advanced MRI in aniridia.

Ann Clin Transl Neurol 2016 05 12;3(5):314-30. Epub 2016 Apr 12.

Department of Clinical and Experimental Epilepsy UCL Institute of Neurology National Hospital for Neurology and Neurosurgery London WC1N 3BG United Kingdom; Epilepsy Society Chalfont-St-Peter Bucks SL9 0RJ United Kingdom.

Objective: PAX6 is a pleiotropic transcription factor essential for the development of several tissues including the eyes, central nervous system, and some endocrine glands. Recently it has also been shown to be important for the maintenance and functioning of corneal and pancreatic tissues in adults. We hypothesized that PAX6 is important for the maintenance of brain integrity in humans, and that adult heterozygotes may have abnormalities of cortical patterning analogous to those found in mouse models.

Methods: We used advanced magnetic resonance imaging techniques, including surface-based morphometry and region-of-interest analysis in adult humans heterozygously mutated for PAX6 mutations (n = 19 subjects and n = 21 controls). Using immunohistochemistry, we also studied PAX6 expression in the adult brain tissue of healthy subjects (n = 4) and patients with epilepsy (n = 42), some of whom had focal injuries due to intracranial electrode track placement (n = 17).

Results: There were significant reductions in frontoparietal cortical area after correcting for age and intracranial volume. A greater decline in thickness of the frontoparietal cortex with age, in subjects with PAX6 mutations compared to controls, correlated with age-corrected, accelerated decline in working memory. These results also demonstrate genotypic effects: those subjects with the most severe genotypes have the most widespread differences compared with controls. We also demonstrated significant increases in PAX6-expressing cells in response to acute injury in the adult human brain.

Interpretation: These findings suggest a role for PAX6 in the maintenance and consequent functioning of the adult brain, homologous to that found in other tissues. This has significant implications for the understanding and treatment of neurodegenerative diseases.
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http://dx.doi.org/10.1002/acn3.297DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4863745PMC
May 2016

NeuroKinect: A Novel Low-Cost 3Dvideo-EEG System for Epileptic Seizure Motion Quantification.

PLoS One 2016 22;11(1):e0145669. Epub 2016 Jan 22.

Epilepsy Center, Department of Neurology, University of Munich, Munich, Germany.

Epilepsy is a common neurological disorder which affects 0.5-1% of the world population. Its diagnosis relies both on Electroencephalogram (EEG) findings and characteristic seizure-induced body movements--called seizure semiology. Thus, synchronous EEG and (2D)video recording systems (known as Video-EEG) are the most accurate tools for epilepsy diagnosis. Despite the establishment of several quantitative methods for EEG analysis, seizure semiology is still analyzed by visual inspection, based on epileptologists' subjective interpretation of the movements of interest (MOIs) that occur during recorded seizures. In this contribution, we present NeuroKinect, a low-cost, easy to setup and operate solution for a novel 3Dvideo-EEG system. It is based on a RGB-D sensor (Microsoft Kinect camera) and performs 24/7 monitoring of an Epilepsy Monitoring Unit (EMU) bed. It does not require the attachment of any reflectors or sensors to the patient's body and has a very low maintenance load. To evaluate its performance and usability, we mounted a state-of-the-art 6-camera motion-capture system and our low-cost solution over the same EMU bed. A comparative study of seizure-simulated MOIs showed an average correlation of the resulting 3D motion trajectories of 84.2%. Then, we used our system on the routine of an EMU and collected 9 different seizures where we could perform 3D kinematic analysis of 42 MOIs arising from the temporal (TLE) (n = 19) and extratemporal (ETE) brain regions (n = 23). The obtained results showed that movement displacement and movement extent discriminated both seizure MOI groups with statistically significant levels (mean = 0.15 m vs. 0.44 m, p<0.001; mean = 0.068 m(3) vs. 0.14 m(3), p<0.05, respectively). Furthermore, TLE MOIs were significantly shorter than ETE (mean = 23 seconds vs 35 seconds, p<0.01) and presented higher jerking levels (mean = 345 ms(-3) vs 172 ms(-3), p<0.05). Our newly implemented 3D approach is faster by 87.5% in extracting body motion trajectories when compared to a 2D frame by frame tracking procedure. We conclude that this new approach provides a more comfortable (both for patients and clinical professionals), simpler, faster and lower-cost procedure than previous approaches, therefore providing a reliable tool to quantitatively analyze MOI patterns of epileptic seizures in the routine of EMUs around the world. We hope this study encourages other EMUs to adopt similar approaches so that more quantitative information is used to improve epilepsy diagnosis.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0145669PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4723069PMC
July 2016

Ruptured basilar artery perforator aneurysms--treatment regimen and long-term follow-up in eight cases.

Neuroradiology 2016 Mar 23;58(3):285-91. Epub 2015 Dec 23.

Department of Neuroradiology, Institute of Clinical Radiology, Grosshadern Campus, Marchioninistr 15, D-81377, Munich, Germany.

Introduction: Basilar artery (BA) perforator aneurysms may lead to severe subarachnoid hemorrhage (SAH). The acute management is uncertain. The anatomic approach is challenging both for coiling and clipping, and flow diverter stenting may be dangerous due to the required antiplatelet therapy. We report on our experiences in eight patients.

Methods: We retrospectively analyzed eight patients with ruptured BA perforator aneurysm, including clinical characteristics, imaging data, treatment regimen, clinical course, and long-term outcome.

Results: Patients presented with major SAH and World Federation of Neurosurgical Societies (WFNS) scores of I in three, II in two, and V in three cases. In four patients, the aneurysm was detected in the initial angiography, in four only in follow-up angiography. Five patients were treated conservatively and three patients had endovascular therapy. In the conservative group, the aneurysm spontaneously thrombosed in three cases. One patient suffered from a re-SAH and stayed permanently dependent due to an associated perforator stroke (modified Rankin Scale (mRS) 5). The remaining four patients recovered well (mRS 0 and 1 in two cases, each) including three patients also exhibiting perforator strokes. Regarding the endovascular group, one parent vessel was an angioma feeder and embolized with Onyx. The second aneurysm spontaneously thrombosed periinterventionally. The third patient underwent coiling. Two parent vessels were occluded postinterventionally, resulting in perforator strokes. Final mRS scores were 0, 2, and 2, respectively.

Conclusion: Conservative management of ruptured BA aneurysms might be a first-line treatment option with common spontaneous aneurysm occlusion, low rate of re-SAH, and promising clinical outcome.
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http://dx.doi.org/10.1007/s00234-015-1634-1DOI Listing
March 2016