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Estimation and Removal of spurious echo Artifacts in single-voxel MRS using Sensitivity Encoding [article]

Adam Berrington, Michal Povazan, Peter B Barker
2020 medRxiv   pre-print
Purpose: In localized MR spectroscopy, spurious echo artifacts commonly occur when unsuppressed signal outside the volume-of-interest is excited and refocused. In the spectral domain, these signals often overlap with metabolite resonances and hinder accurate quantification. Since the artifacts originate from regions separate from the target MRS voxel, this work proposes that sensitivity encoding based on receive coil sensitivity profiles may be used to separate these signal contributions.
more » ... s: Numerical simulations were performed to explore the effect of sensitivity encoded separation for unknown artifact regions. An imaging-based approach was developed to identify regions that may contribute to spurious echo artifacts, and tested for sensitivity-based unfolding of signal contribution on 6 datasets from 3 brain regions. Spectral data reconstructed using the proposed method ('ERASE') were compared to standard coil combination. Results: The method was able to fully separate metabolite and artifact signals if regions were known a priori. Mismatch between estimated and actual artifact locations reduced the efficiency of artifact removal. Water suppression imaging (WSI) was able to identify unsuppressed signal remote from the MRS voxel in all cases, and ERASE reconstruction (of up to 8 distinct locations) led to improvements in spectral quality and reduced fitting errors for the major metabolites compared to standard reconstruction, without significant degradation of spectral SNR. Conclusion: The ERASE reconstruction tool was demonstrated to reduce spurious echo artifacts in single voxel MRS. ERASE may be incorporated into standard MRS workflows to improve spectral quality when scanner hardware limitations or other factors result in out-of-voxel signal contamination.
doi:10.1101/2020.09.09.20191460 fatcat:vw63cnv7wzgqjhkxnjx2p5gjne

Calibration-free regional RF shims for MR spectroscopy [article]

Adam Berrington, Michal Považan, Christopher Mirfin, Stephen Bawden, Young Woo Park, Daniel C Marsh, Richard Bowtell, Penny Gowland
2020 biorxiv/medrxiv   pre-print
ORCID Adam Berrington https://orcid.org/0000-0002-1207-8193 TWITTER Adam Berrington @adamberrington  ...  Images were skullstripped | 619 BERRINGTON ET al. 1 | of 1 µT across the central slice in quadrature mode.  ...  Lines through each bar indicate the median value, and shaded region represents 25th to 75th percentiles 618 | BERRINGTON ET al.  ... 
doi:10.1101/2020.07.24.20161141 fatcat:ddpk6notgrcrngsyuy53irdk5m

Estimation and removal of spurious echo artifacts in single‐voxel MRS using sensitivity encoding

Adam Berrington, Michal Považan, Peter B. Barker
2021 Magnetic Resonance in Medicine  
. | 5 BERRINGTON 5 ET al. F I G U R E 7 7 LCModel fitting results for major metabolite signals using standard and ERASE reconstructed spectra for all six in vivo data sets (R01-R06).  ... 
doi:10.1002/mrm.28848 pmid:34184324 fatcat:q3hq35esdbbh3pfdphgqa6wski

Combined fMRI-MRS acquires simultaneous glutamate and BOLD-fMRI signals in the human brain

I. Betina Ip, Adam Berrington, Aaron T. Hess, Andrew J. Parker, Uzay E. Emir, Holly Bridge
2017 NeuroImage  
A B S T R A C T Combined fMRI-MRS is a novel method to non-invasively investigate functional activation in the human brain using simultaneous acquisition of hemodynamic and neurochemical measures. The aim of the current study was to quantify neural activity using combined fMRI-MRS at 7 T. BOLD-fMRI and semi-LASER localization MRS data were acquired from the visual cortex of 13 participants during short blocks (64 s) of flickering checkerboards. We demonstrate a correlation between glutamate and
more » ... BOLD-fMRI time courses (R=0.381, p=0.031). In addition, we show increases in BOLD-fMRI (1.43 ± 0.17%) and glutamate concentrations (0.15 ± 0.05 I.U.,~2%) during visual stimulation. In contrast, we observed no change in glutamate concentrations in resting state MRS data during sham stimulation periods. Spectral line width changes generated by the BOLDresponse were corrected using line broadening. In summary, our results establish the feasibility of concurrent measurements of BOLD-fMRI and neurochemicals using a novel combined fMRI-MRS sequence. Our findings strengthen the link between glutamate and functional activity in the human brain by demonstrating a significant correlation of BOLD-fMRI and glutamate over time, and by showing~2% glutamate increases during 64 s of visual stimulation. Our tool may become useful for studies characterizing functional dynamics between neurochemicals and hemodynamics in health and disease.
doi:10.1016/j.neuroimage.2017.04.030 pmid:28433623 pmcid:PMC5519502 fatcat:yeet4aqr6zat3g5jc4ehuxkewa

BIMG-23. SINGLE-VOXEL VERSUS MULTI-SLICE MRSI IN PATIENTS WITH GLIOMA ON A KETOGENIC DIET INTERVENTION

Vasu Munjapara, David Kamson, Adam Berrington, Roy Strowd, Karisa Schreck, Peter Barker
2020 Neuro-Oncology Advances  
SINGLE-VOXEL VERSUS MULTI-SLICE MRSI IN PATIENTS WITH GLIOMA ON A KETOGENIC DIET INTERVENTION Vasu Munjapara 1 , David Kamson 1,2 , Adam Berrington 3 , Roy Strowd III 4 , Karisa Schreck 1 , Peter Barker  ... 
doi:10.1093/noajnl/vdab024.022 fatcat:bzinoc2rcvfzrnsoguemkykwpm

Modulating Regional Motor Cortical Excitability with Noninvasive Brain Stimulation Results in Neurochemical Changes in Bilateral Motor Cortices

Velicia Bachtiar, Ainslie Johnstone, Adam Berrington, Clark Lemke, Heidi Johansen-Berg, Uzay Emir, Charlotte J. Stagg
2018 Journal of Neuroscience  
Learning a novel motor skill is dependent both on regional changes within the primary motor cortex (M1) contralateral to the active hand and also on modulation between and within anatomically distant but functionally connected brain regions. Interregional changes are particularly important in functional recovery after stroke, when critical plastic changes underpinning behavioral improvements are observed in both ipsilesional and contralesional M1s. It is increasingly understood that reduction
more » ... GABA in the contralateral M1 is necessary to allow learning ofamotortask.However,thephysiologicalmechanismsunderpinningplasticitywithinotherbrainregions,mostimportantlytheipsilateralM1, are not well understood. Here, we used concurrent two-voxel magnetic resonance spectroscopy to simultaneously quantify changes in neuro- chemicals within left and right M1s in healthy humans of both sexes in response to transcranial direct current stimulation (tDCS) applied to left M1. We demonstrated a decrease in GABA in both the stimulated (left) and nonstimulated (right) M1 after anodal tDCS, whereas a decrease in GABA was only observed in nonstimulated M1 after cathodal stimulation. This GABA decrease in the nonstimulated M1 during cathodal tDCS was negatively correlated with microstructure of M1:M1 callosal fibers, as quantified by diffusion MRI, suggesting that structural features of these fibers may mediate GABA decrease in the unstimulated region. We found no significant changes in glutamate. Together, these findings shed light on the interactions between the two major network nodes underpinning motor plasticity, offering a potential framework from which to optimize future interventions to improve motor function after stroke.
doi:10.1523/jneurosci.2853-17.2018 pmid:30030397 pmcid:PMC6096041 fatcat:rkkb6gm3znbmpfpepwvnartofa

Improved localisation for 2-hydroxyglutarate detection at 3T using long-TE semi-LASER

Adam Berrington, Natalie L Voets, Puneet Plaha, Sarah J Larkin, James Mccullagh, Richard Stacey, Muhammed Yildirim, Christopher J Schofield, Peter Jezzard, Tom Cadoux-Hudson, Olaf Ansorge, Uzay E Emir
2016 Tomography  
ACKNOWLEDGMENTS The authors would like to acknowledge the following: ESPRC fully funded studentship (A Berrington), HDH Wills 1965 Charitable Trust and NIHR Oxford Biomedical Research  ... 
pmid:27547821 pmcid:PMC4990123 fatcat:uz6avv5465dkxmurohziqnd7na

DDRE-31. FEASIBILITY AND BIOLOGIC ACTIVITY OF A KETOGENIC / INTERMITTENT FASTING DIET IN GLIOMA PATIENTS

Karisa Schreck, Fang-Chi Hsu, Adam Berrington, Bobbie Henry-Barron, Diane Vizthum, Lindsay Blair, Eric Kossoff, Linda Easter, Christopher Whitlow, Mackenzie Cervenka, Peter Barker, Jaishri Blakeley (+1 others)
2020 Neuro-Oncology Advances  
FEASIBILITY AND BIOLOGIC ACTIVITY OF A KETOGENIC / INTERMITTENT FASTING DIET IN GLIOMA PATIENTS Karisa Schreck 1 , Fang-Chi Hsu 2 , Adam Berrington 3 , Bobbie Henry-Barron 1 , Diane Vizthum 1 , Lindsay  ... 
doi:10.1093/noajnl/vdab024.053 fatcat:ughd66smdrcitpkprn2ea3a4j4

Effects of the potential lithium-mimetic, ebselen, on brain neurochemistry: a magnetic resonance spectroscopy study at 7 tesla

Charles Masaki, Ann L. Sharpley, Beata R. Godlewska, Adam Berrington, Tasuku Hashimoto, Nisha Singh, Sridhar R. Vasudevan, Uzay E. Emir, Grant C. Churchill, Philip J. Cowen
2016 Psychopharmacology  
2016). Effects of the potential lithium-mimetic, ebselen, on brain neurochemistry: a magnetic resonance spectroscopy study at 7 tesla. Psychopharmacology, 233(6), Abstract Rationale Lithium is an effective treatment for bipolar disorder, but safety issues complicate its clinical use. The antioxidant drug, ebselen, may be a possible lithium-mimetic based on its ability to inhibit inositol monophosphatase (IMPase), an action which it shares with lithium. Objectives Our primary aim was to
more » ... whether ebselen lowered levels of inositol in the human brain. We also assessed the effect of ebselen on other brain neurometabolites, including glutathione, glutamate, glutamine, and glutamate + glutamine (Glx) Methods Twenty healthy volunteers were tested on two occasions receiving either ebselen (3600 mg over 24 h) or identical placebo in a double-blind, random-order, crossover design. Two hours after the final dose of ebselen/placebo, participants underwent proton magnetic resonance spectroscopy ( 1 H MRS) at 7 tesla (T) with voxels placed in the anterior cingulate and occipital cortex. Neurometabolite levels were calculated using an unsuppressed water signal as a reference and corrected for individual cerebrospinal fluid content in the voxel. Results Ebselen produced no effect on neurometabolite levels in the occipital cortex. In the anterior cingulate cortex, ebselen lowered concentrations of inositol (p = 0.028, Cohen's d = 0.60) as well as those of glutathione (p = 0.033, d = 0.58), glutamine (p = 0.024, d = 0.62), glutamate (p = 0.01, d = 0.73), and Glx (p = 0.001, d = 1.0). Conclusions The study suggests that ebselen produces a functional inhibition of IMPase in the human brain. The effect of ebselen to lower glutamate is consistent with its reported ability to inhibit the enzyme, glutaminase. Ebselen may have potential as a repurposed treatment for bipolar disorder.
doi:10.1007/s00213-015-4189-2 pmid:26758281 pmcid:PMC4759215 fatcat:6vgiakfqbfcozhc5dj73jrlwb4

tDCS induced GABA change is associated with the simulated electric field in M1, an effect mediated by grey matter volume in the MRS voxel [article]

Tulika Nandi, Oula Puonti, William T. Clarke, Caroline Nettekoven, Helen C. Barron, James Kolasinski, Taylor Hanayik, Emily L. Hinson, Adam Berrington, Velicia Bachtiar, Ainslie Johnstone, Anderson M. Winkler (+3 others)
2022 bioRxiv   pre-print
AbstractBackground and ObjectiveTranscranial direct current stimulation (tDCS) has wide ranging applications in neuro-behavioural and physiological research, and in neurological rehabilitation. However, it is currently limited by substantial inter-subject variability in responses, which may be explained, at least in part, by anatomical differences that lead to variability in the electric field (E-field) induced in the cortex. Here, we tested whether the variability in the E-field in the
more » ... ed cortex during tDCS, estimated using computational simulations, explains the variability in tDCS induced changes in GABA, a neurophysiological marker of stimulation effect.MethodsData from five previously conducted MRS studies were combined. The anode was placed over the left primary motor cortex (M1, 3 studies, N = 24) or right temporal cortex (2 studies, N = 32), with the cathode over the contralateral supraorbital ridge. Single voxel spectroscopy was performed in a 2×2×2cm voxel under the anode in all cases. MRS data were acquired before and either during or after 1mA tDCS using either a sLASER sequence (7T) or a MEGA-PRESS sequence (3T). sLASER MRS data were analysed using LCModel, and MEGA-PRESS using FID-A and Gannet. E-fields were simulated in a finite element model of the head, based on individual MPRAGE images, using SimNIBS. Separate linear mixed effects models were run for each E-field variable (mean and 95th percentile; magnitude, and components normal and tangential to grey matter surface, within the MRS voxel). The model included effects of time (pre or post tDCS), E-field, grey matter volume in the MRS voxel, and a 3-way interaction between time, E-field and grey matter volume. Additionally, we ran a permutation analysis using PALM to determine whether E-field anywhere in the brain, not just in the MRS voxel, correlated with GABA change.ResultsIn M1, higher mean E-field magnitude was associated with greater tDCS-induced decreases in GABA (t(24) = 3.24, p = 0.003). Further, the association between mean E-field magnitude and GABA change was moderated by the grey matter volume in the MRS voxel (t(24) = −3.55, p =0.002). These relationships were consistent across all E-field variables except the mean of the normal component. No significant relationship was found between tDCS-induced GABA decrease and E-field in the temporal voxel. No significant clusters were found in the whole brain analysis.ConclusionsOur data suggest that the electric field induced by tDCS within the brain is variable, and is significantly related to tDCS-induced decrease in GABA, a key neurophysiological marker of stimulation. These findings strongly support individualised dosing of tDCS, at least in M1. Further studies examining E-fields in relation to other outcome measures, including behaviour, will help determine the optimal E-fields required for any desired effects.HighlightsWe study the link between individually simulated electric field dose and tDCS-induced change in GABA in the cortex.The electric field strength in the brain correlates with a decrease in GABA in the motor cortex.The correlation between the electric field and GABA change is modulated by the amount of grey matter in the MRS voxel.We find no association between the electric field and GABA in the temporal cortex.
doi:10.1101/2022.04.27.489665 fatcat:dqqkxyc7fjfbfg4xxl5yekgrhi

tDCS induced GABA change is associated with the simulated electric field in M1, an effect mediated by grey matter volume in the MRS voxel

Tulika Nandi, Oula Puonti, William T. Clarke, Caroline Nettekoven, Helen C. Barron, James Kolasinski, Taylor Hanayik, Emily L. Hinson, Adam Berrington, Velicia Bachtiar, Ainslie Johnstone, Anderson M. Winkler (+3 others)
2022 Brain Stimulation  
Transcranial direct current stimulation (tDCS) has wide ranging applications in neuro-behavioural and physiological research, and in neurological rehabilitation. However, it is currently limited by substantial inter-subject variability in responses, which may be explained, at least in part, by anatomical differences that lead to variability in the electric field (E-field) induced in the cortex. Here, we tested whether the variability in the E-field in the stimulated cortex during anodal tDCS,
more » ... timated using computational simulations, explains the variability in tDCS induced changes in GABA, a neurophysiological marker of stimulation effect. Data from five previously conducted MRS studies were combined. The anode was placed over the left primary motor cortex (M1, 3 studies, N = 24) or right temporal cortex (2 studies, N = 32), with the cathode over the contralateral supraorbital ridge. Single voxel spectroscopy was performed in a 2 × 2x2cm voxel under the anode in all cases. MRS data were acquired before and either during or after 1mA tDCS using either a sLASER sequence (7T) or a MEGA-PRESS sequence (3T). sLASER MRS data were analysed using LCModel, and MEGA-PRESS using FID-A and Gannet. E-fields were simulated in a finite element model of the head, based on individual MPRAGE images, using SimNIBS. Separate linear mixed effects models were run for each E-field variable (mean and 95th percentile; magnitude, and components normal and tangential to grey matter surface, within the MRS voxel). The model included effects of time (pre or post tDCS), E-field, grey matter volume in the MRS voxel, and a 3-way interaction between time, E-field and grey matter volume. Additionally, we ran a permutation analysis using PALM to determine whether E-field anywhere in the brain, not just in the MRS voxel, correlated with GABA change. In M1, higher mean E-field magnitude was associated with greater anodal tDCS-induced decreases in GABA (t(24) = 3.24, p = 0.003). Further, the association between mean E-field magnitude and GABA change was moderated by the grey matter volume in the MRS voxel (t(24) = -3.55, p = 0.002). These relationships were consistent across all E-field variables except the mean of the normal component. No significant relationship was found between tDCS-induced GABA decrease and E-field in the temporal voxel. No significant clusters were found in the whole brain analysis. Our data suggest that the electric field induced by tDCS within the brain is variable, and is significantly related to anodal tDCS-induced decrease in GABA, a key neurophysiological marker of stimulation. These findings strongly support individualised dosing of tDCS, at least in M1. Further studies examining E-fields in relation to other outcome measures, including behaviour, will help determine the optimal E-fields required for any desired effects.
doi:10.1016/j.brs.2022.07.049 pmid:35988862 fatcat:slzz3ecn3ffv3baq2obxj5fhxm

Comparison of Multivendor Single-Voxel MR Spectroscopy Data Acquired in Healthy Brain at 26 Sites

Michal Považan, Mark Mikkelsen, Adam Berrington, Pallab K. Bhattacharyya, Maiken K. Brix, Pieter F. Buur, Kim M. Cecil, Kimberly L. Chan, David Y.T. Chen, Alexander R. Craven, Koen Cuypers, Michael Dacko (+9 others)
2020 Radiology  
Bigley of the University of Sheffield MRI Unit for her assistance with data acquisition.Complete list of authors:Michal Považan, PhD; Mark Mikkelsen, PhD; Adam Berrington, PhD; Pallab K.  ...  Wilkinson, PhD; Hans-Jörg Wittsack, PhD; Adam J. Woods, PhD; Hongmin Xu, PhD; Fuhua Yan, MD; Chencheng Zhang, MD; Vadim Zipunnikov, PhD; Helge J. Zöllner, PhD; Richard A.E. Edden, PhD; and Peter B.  ... 
doi:10.1148/radiol.2020191037 pmid:32043950 pmcid:PMC7104702 fatcat:i7rl3z6dfbhrjnu5dc37nmjh3i

Connectivity Guided Theta Burst Transcranial Magnetic Stimulation Versus Repetitive Transcranial Magnetic Stimulation for Treatment Resistant Moderate to Severe Depression: Magnetic Resonance Imaging Protocol and SARS COVID-19 induced changes for a Randomised Double-blind Controlled Trial (BRIGhTMIND) (Preprint)

Stefan Pszczolkowski, William J. Cottam, Paul M. Briley, Sarina J. Iwabuchi, Catherine Kaylor-Hughes, Abdulrhman Shalabi, Ben Babourina-Brooks, Adam Berrington, Shaun Barber, Ana Suazo Di Paola, Andrew Blamire, Hamish McAllister-Williams (+7 others)
2021 JMIR Research Protocols  
Depression is a substantial health and economic burden. In approximately one-third of patients, depression is resistant to first-line treatment; therefore, it is essential to find alternative treatments. Transcranial magnetic stimulation (TMS) is a neuromodulatory treatment involving the application of magnetic pulses to the brain that is approved in the United Kingdom and the United States in treatment-resistant depression. This trial aims to compare the clinical effectiveness,
more » ... ss, and mechanism of action of standard treatment repetitive TMS (rTMS) targeted at the F3 electroencephalogram site with a newer treatment-a type of TMS called theta burst stimulation (TBS) targeted based on measures of functional brain connectivity. This protocol outlines brain imaging acquisition and analysis for the Brain Imaging Guided Transcranial Magnetic Stimulation in Depression (BRIGhTMIND) study trial that is used to create personalized TMS targets and answer the proposed mechanistic hypotheses. The aims of the imaging arm of the BRIGhTMIND study are to identify functional and neurochemical brain signatures indexing the treatment mechanisms of rTMS and connectivity-guided intermittent theta burst TMS and to identify imaging-based markers predicting response to treatment. The study is a randomized double-blind controlled trial with 1:1 allocation to either 20 sessions of TBS or standard rTMS. Multimodal magnetic resonance imaging (MRI) is acquired for each participant at baseline (before TMS treatment) with T1-weighted and task-free functional MRI during rest used to estimate TMS targets. For participants enrolled in the mechanistic substudy, additional diffusion-weighted sequences are acquired at baseline and at posttreatment follow-up 16 weeks after treatment randomization. Core data sets of T1-weighted and task-free functional MRI during rest are acquired for all participants and are used to estimate TMS targets. Additional sequences of arterial spin labeling, magnetic resonance spectroscopy, and diffusion-weighted images are acquired depending on the recruitment site for mechanistic evaluation. Standard rTMS treatment is targeted at the F3 electrode site over the left dorsolateral prefrontal cortex, whereas TBS treatment is guided using the coordinate of peak effective connectivity from the right anterior insula to the left dorsolateral prefrontal cortex. Both treatment targets benefit from the level of MRI guidance, but only TBS is provided with precision targeting based on functional brain connectivity. Recruitment began in January 2019 and is ongoing. Data collection is expected to continue until January 2023. This trial will determine the impact of precision MRI guidance on rTMS treatment and assess the neural mechanisms underlying this treatment in treatment-resistant depressed patients. ISRCTN Registry ISRCTN19674644; https://www.isrctn.com/ISRCTN19674644. DERR1-10.2196/31925.
doi:10.2196/31925 pmid:35049517 pmcid:PMC8814922 fatcat:b4f6bececnhanpcj52s3vq5j6a

Page 231 of Archaeologia Cambrensis Vol. 14, Issue 55 [page]

1883 Archaeologia Cambrensis  
Dictus siquidem Adam et omnes successores sui fidelitatem nobis et domui nostre jurabunt se prestaturos et ecclesie nostre in- dempnitatem jurabunt et predictum redditum trium solidorum ad prenominatum  ...  The Abbot of the Convent of Lire acknowledges that the Manor and Mill of Berrington were free from tithes, the Abbot of Lyre taking his accustomed two acres of land sown with grain.  ... 

Page 336 of The New England Historical and Genealogical Register Vol. 55, Issue [page]

1901 The New England Historical and Genealogical Register  
Wrington is near Berrington in the same Hundred—. e. Brent with Wrington.  ...  Witn:— Thomas Elbrough, Richard Adams & Robert Prue, Vicar of Pirton. Pro. at Lon- don 4 Oct., 1595, by Thomas Lovell, Not. Pub., Atty. for Exor. named. P. C. C.  ... 
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