Focke, Niels K.

[["dc.bibliographiccitation.firstpage","246"],["dc.bibliographiccitation.issue","3"],["dc.bibliographiccitation.journal","Epilepsy Research"],["dc.bibliographiccitation.lastpage","254"],["dc.bibliographiccitation.volume","95"],["dc.contributor.author","Bonelli, Silvia B."],["dc.contributor.author","Powell, Rob"],["dc.contributor.author","Thompson, Pamela J."],["dc.contributor.author","Yogarajah, Mahinda"],["dc.contributor.author","Focke, Niels K."],["dc.contributor.author","Stretton, Jason"],["dc.contributor.author","Vollmar, Christian"],["dc.contributor.author","Symms, Mark R."],["dc.contributor.author","Price, Cathy J."],["dc.contributor.author","Duncan, John S."],["dc.contributor.author","Koepp, Matthias J."],["dc.date.accessioned","2018-11-07T08:53:33Z"],["dc.date.available","2018-11-07T08:53:33Z"],["dc.date.issued","2011"],["dc.description.abstract","Purpose: In patients with left temporal lobe epilepsy (TLE) due to hippocampal sclerosis (HS) decreased naming ability is common, suggesting a critical role for the medial left temporal lobe in this task. We investigated the integrity of language networks with functional MRI (fMRI) in controls and TLE patients. Experimental design: We performed an fMRI verbal fluency paradigm in 22 controls and 66 patients with unilateral mesial TLE (37 left HS, 29 right HS). Verbal fluency and naming ability were investigated as part of the standard presurgical neuropsychological assessment. Naming ability was assessed using a visual confrontation naming test. Results: Left TLE patients had significantly tower naming scores than controls and those with right TLE. Right TLE patients performed less well than controls, but better than those with left TLE. Left TLE had significantly lower scores for verbal fluency than controls. In controls and right TLE, left hippocampal activation during the verbal fluency task was significantly correlated with naming, characterised by higher scores in subjects with greater hippocampal fMRI activation. In left TLE no correlation with naming scores was seen in the left hippocampus, but there was a significant correlation in the left middle and inferior frontal gyri, not observed in controls and right TLE. In left and right TLE, out of scanner verbal fluency scores significantly correlated with fMRI activation for verbal fluency in the left middle and inferior frontal gyri. Conclusion: Good confrontation naming ability depends on the integrity of the hippocampus and the connecting fronto-temporal networks. Functional MRI activation in the left hippocampus during verbal fluency is associated with naming function in healthy controls and patients with right TLE. In left TLE, there was evidence of involvement of the left frontal lobe when naming was more proficient, most likely reflecting a compensatory response due to the ongoing epileptic activity and/or underlying pathology. (C) 2011 Elsevier B.V. All rights reserved."],["dc.identifier.doi","10.1016/j.eplepsyres.2011.04.007"],["dc.identifier.isi","000293727600009"],["dc.identifier.pmid","21592730"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/11299"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/22438"],["dc.notes.intern","Merged from goescholar"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Elsevier Science Bv"],["dc.relation.issn","0920-1211"],["dc.rights","CC BY 3.0"],["dc.rights.uri","https://creativecommons.org/licenses/by/3.0"],["dc.title","Hippocampal activation correlates with visual confrontation naming: fMRI findings in controls and patients with temporal lobe epilepsy"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","1653"],["dc.bibliographiccitation.issue","9"],["dc.bibliographiccitation.journal","Epilepsia"],["dc.bibliographiccitation.lastpage","1664"],["dc.bibliographiccitation.volume","58"],["dc.contributor.author","Martin, Pascal"],["dc.contributor.author","Winston, Gavin P."],["dc.contributor.author","Bartlett, Philippa"],["dc.contributor.author","de Tisi, Jane"],["dc.contributor.author","Duncan, John S."],["dc.contributor.author","Focke, Niels K."],["dc.date.accessioned","2019-12-16T15:44:53Z"],["dc.date.accessioned","2021-10-27T13:21:57Z"],["dc.date.available","2019-12-16T15:44:53Z"],["dc.date.available","2021-10-27T13:21:57Z"],["dc.date.issued","2017"],["dc.description.abstract","OBJECTIVE: Although the general utility of voxel-based processing of structural magnetic resonance imaging (MRI) data for detecting occult lesions in focal epilepsy is established, many differences exist among studies, and it is unclear which processing method is preferable. The aim of this study was to compare the ability of commonly used methods to detect epileptogenic lesions in magnetic resonance MRI-positive and MRI-negative patients, and to estimate their diagnostic yield. METHODS: We identified 144 presurgical focal epilepsy patients, 15 of whom had a histopathologically proven and MRI-visible focal cortical dysplasia; 129 patients were MRI negative with a clinical hypothesis of seizure origin, 27 of whom had resections. We applied four types of voxel-based morphometry (VBM), three based on T1 images (gray matter volume, gray matter concentration, junction map [JM]) and one based on normalized fluid-attenuated inversion recovery (nFSI). Specificity was derived from analysis of 50 healthy controls. RESULTS: The four maps had different sensitivity and specificity profiles. All maps showed detection rates for focal cortical dysplasia patients (MRI positive and negative) of >30% at a strict threshold of p < 0.05 (family-wise error) and >60% with a liberal threshold of p < 0.0001 (uncorrected), except for gray matter volume (14% and 27% detection rate). All maps except nFSI showed poor specificity, with high rates of false-positive findings in controls. In the MRI-negative patients, absolute detection rates were lower. A concordant nFSI finding had a significant positive odds ratio of 7.33 for a favorable postsurgical outcome in the MRI-negative group. Spatial colocalization of JM and nFSI was rare, yet showed good specificity throughout the thresholds. SIGNIFICANCE: All VBM variants had specific diagnostic properties that need to be considered for an adequate interpretation of the results. Overall, structural postprocessing can be a useful tool in presurgical diagnostics, but the low specificity of some maps has to be taken into consideration."],["dc.identifier.doi","10.1111/epi.13851"],["dc.identifier.isbn","28745400"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/16969"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/92057"],["dc.language.iso","en"],["dc.notes.intern","Migrated from goescholar"],["dc.relation.issn","0013-9580"],["dc.relation.orgunit","Universitätsmedizin Göttingen"],["dc.rights","CC BY 4.0"],["dc.rights.uri","https://creativecommons.org/licenses/by/4.0"],["dc.subject.ddc","610"],["dc.title","Voxel-based magnetic resonance image postprocessing in epilepsy"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","1656"],["dc.bibliographiccitation.journal","Brain"],["dc.bibliographiccitation.lastpage","1668"],["dc.bibliographiccitation.volume","132"],["dc.contributor.author","Yogarajah, Mahinda"],["dc.contributor.author","Focke, Niels K."],["dc.contributor.author","Bonelli, Silvia B."],["dc.contributor.author","Cercignani, M."],["dc.contributor.author","Acheson, J."],["dc.contributor.author","Parker, G. J. M."],["dc.contributor.author","Alexander, Daniel C."],["dc.contributor.author","McEvoy, A. W."],["dc.contributor.author","Symms, Mark R."],["dc.contributor.author","Koepp, Matthias J."],["dc.contributor.author","Duncan, John S."],["dc.date.accessioned","2018-11-07T08:28:58Z"],["dc.date.available","2018-11-07T08:28:58Z"],["dc.date.issued","2009"],["dc.description.abstract","Anterior temporal lobe resection is often complicated by superior quadrantic visual field deficits (VFDs). In some cases this can be severe enough to prohibit driving, even if a patient is free of seizures. These deficits are caused by damage to Meyers loop of the optic radiation, which shows considerable heterogeneity in its anterior extent. This structure cannot be distinguished using clinical magnetic resonance imaging sequences. Diffusion tensor tractography is an advanced magnetic resonance imaging technique that enables the parcellation of white matter. Using seed voxels antero-lateral to the lateral geniculate nucleus, we applied this technique to 20 control subjects, and 21 postoperative patients. All patients had visual fields assessed with Goldmann perimetry at least three months after surgery. We measured the distance from the tip of Meyers loop to the temporal pole and horn in all subjects. In addition, we measured the size of temporal lobe resection using postoperative T-1-weighted images, and quantified VFDs. Nine patients suffered VFDs ranging from 22 to 87 of the contralateral superior quadrant. In patients, the range of distance from the tip of Meyers loop to the temporal pole was 2443 mm (mean 34 mm), and the range of distance from the tip of Meyers loop to the temporal horn was 15 to 9 mm (mean 0 mm). In controls the range of distance from the tip of Meyers loop to the temporal pole was 2447 mm (mean 35 mm), and the range of distance from the tip of Meyers loop to the temporal horn was 11 to 9 mm (mean 0 mm). Both quantitative and qualitative results were in accord with recent dissections of cadaveric brains, and analysis of postoperative VFDs and resection volumes. By applying a linear regression analysis we showed that both distance from the tip of Meyers loop to the temporal pole and the size of resection were significant predictors of the postoperative VFDs. We conclude that there is considerable variation in the anterior extent of Meyers loop. In view of this, diffusion tensor tractography of the optic radiation is a potentially useful method to assess an individual patients risk of postoperative VFDs following anterior temporal lobe resection."],["dc.identifier.doi","10.1093/brain/awp114"],["dc.identifier.isi","000266498400031"],["dc.identifier.pmid","19460796"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/13540"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/16542"],["dc.notes.intern","Merged from goescholar"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Oxford Univ Press"],["dc.relation.issn","1460-2156"],["dc.relation.issn","0006-8950"],["dc.rights","CC BY-NC 2.0"],["dc.rights.uri","https://creativecommons.org/licenses/byby-nc/2.0"],["dc.title","Defining Meyers looptemporal lobe resections, visual field deficits and diffusion tensor tractography"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","2348"],["dc.bibliographiccitation.journal","Brain"],["dc.bibliographiccitation.lastpage","2364"],["dc.bibliographiccitation.volume","133"],["dc.contributor.author","Yogarajah, Mahinda"],["dc.contributor.author","Focke, Niels K."],["dc.contributor.author","Bonelli, Silvia B."],["dc.contributor.author","Thompson, Pamela J."],["dc.contributor.author","Vollmar, Christian"],["dc.contributor.author","McEvoy, Andrew W."],["dc.contributor.author","Alexander, Daniel C."],["dc.contributor.author","Symms, Mark R."],["dc.contributor.author","Koepp, Matthias J."],["dc.contributor.author","Duncan, John S."],["dc.date.accessioned","2018-11-07T08:40:38Z"],["dc.date.available","2018-11-07T08:40:38Z"],["dc.date.issued","2010"],["dc.description.abstract","Anterior temporal lobe resection is an effective treatment for refractory temporal lobe epilepsy. The structural consequences of such surgery in the white matter, and how these relate to language function after surgery remain unknown. We carried out a longitudinal study with diffusion tensor imaging in 26 left and 20 right temporal lobe epilepsy patients before and a mean of 4.5 months after anterior temporal lobe resection. The whole-brain analysis technique tract-based spatial statistics was used to compare pre- and postoperative data in the left and right temporal lobe epilepsy groups separately. We observed widespread, significant, mean 7%, decreases in fractional anisotropy in white matter networks connected to the area of resection, following both left and right temporal lobe resections. However, we also observed a widespread, mean 8%, increase in fractional anisotropy after left anterior temporal lobe resection in the ipsilateral external capsule and posterior limb of the internal capsule, and corona radiata. These findings were confirmed on analysis of the native clusters and hand drawn regions of interest. Postoperative tractography seeded from this area suggests that this cluster is part of the ventro-medial language network. The mean pre- and postoperative fractional anisotropy and parallel diffusivity in this cluster were significantly correlated with postoperative verbal fluency and naming test scores. In addition, the percentage change in parallel diffusivity in this cluster was correlated with the percentage change in verbal fluency after anterior temporal lobe resection, such that the bigger the increase in parallel diffusivity, the smaller the fall in language proficiency after surgery. We suggest that the findings of increased fractional anisotropy in this ventro-medial language network represent structural reorganization in response to the anterior temporal lobe resection, which may damage the more susceptible dorso-lateral language pathway. These findings have important implications for our understanding of brain injury and rehabilitation, and may also prove useful in the prediction and minimization of postoperative language deficits."],["dc.identifier.doi","10.1093/brain/awq175"],["dc.identifier.isi","000280982700016"],["dc.identifier.pmid","20826432"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/13538"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/19278"],["dc.notes.intern","Merged from goescholar"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Oxford Univ Press"],["dc.relation.issn","0006-8950"],["dc.rights","CC BY-NC 2.5"],["dc.rights.uri","https://creativecommons.org/licenses/by-nc/2.5"],["dc.title","The structural plasticity of white matter networks following anterior temporal lobe resection"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","3351"],["dc.bibliographiccitation.issue","10"],["dc.bibliographiccitation.journal","Human Brain Mapping"],["dc.bibliographiccitation.lastpage","3360"],["dc.bibliographiccitation.volume","30"],["dc.contributor.author","Eriksson, Sofia H."],["dc.contributor.author","Thom, Maria"],["dc.contributor.author","Symms, Mark R."],["dc.contributor.author","Focke, Niels K."],["dc.contributor.author","Martinian, Lillian"],["dc.contributor.author","Sisodiya, Sanjay M."],["dc.contributor.author","Duncan, John S."],["dc.date.accessioned","2018-11-07T11:23:44Z"],["dc.date.available","2018-11-07T11:23:44Z"],["dc.date.issued","2009"],["dc.description.abstract","Voxel-based morphometry (VBM) has detected differences between brains of groups of patients with epilepsy and controls, but the sensitivity for detecting subtle pathological changes in single subjects has not been established. The aim of the study was to test the sensitivity of VBM using statistical parametric niapping (SPM5) to detect hippocampal sclerosis (HS) and cortical neuronal loss in individual patients. T1-weighted volumetric 1.5 T MR images from 13 patients with HS and laminar cortical neuronal loss were segmented, normalised and smoothed using SPM5. Both modulated and non-modulated analyses were performed. Comparisons of one control subject against the rest (n = 23) were first performed to ascertain the smoothing level with the lowest number of SPM changes in controls. Each patient was then compared against the whole control group. The lowest number of SPM changes in control Subjects was found at a smoothing level of 10 mm full width half maximum for modulated and non-modulated data. In the patient group, no SPM abnormalities were found in the affected temporal lobe or hippocampus at this smoothing level. At lower smoothing levels there were numerous SPM findings in controls and patients. VBM did not detect any abnormalities associated with either laminar cortical neuronal loss or HS. This may be due to normalisation and smoothing of images and low statistical power in areas with larger interindividual differences. This suggests that the methodology may currently not be suitable to detect particular occult abnormalities possibly associated with seizure onset zone in individual epilepsy patients with unremarkable standard structural MRI. Hum Brain Mapp 30:3351-3360, 2009. (C) 2009 Wiley-Liss, Inc."],["dc.description.sponsorship","Welcome Trust [066185]"],["dc.identifier.doi","10.1002/hbm.20757"],["dc.identifier.isi","000270853700023"],["dc.identifier.pmid","19347875"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/14052"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/56252"],["dc.notes.intern","Merged from goescholar"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Wiley-blackwell"],["dc.relation.issn","1065-9471"],["dc.rights","Goescholar"],["dc.rights.uri","https://goescholar.uni-goettingen.de/licenses"],["dc.title","Cortical Neuronal Loss and Hippocampal Sclerosis are not Detected by Voxel-Based Morphometry in Individual Epilepsy Surgery Patients"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]