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Optimizing neuromelanin contrast in the substantia nigra and locus coeruleus using a magnetization transfer contrast prepared 3D gradient recalled echo sequence

Yu Liu, Junchen Li, Naying He, Yongsheng Chen, Zhijia Jin, Fuhua Yan, E. Mark Haacke
2020 NeuroImage  
Neuromelanin (NM) loss in the substantia nigra (SN) and locus coeruleus (LC) is being investigated as an imaging biomarker for Parkinson's disease (PD) using magnetization transfer contrast (MTC) magnetic  ...  Therefore, the goal of this paper was to optimize the NM contrast in the SN and LC as a function of flip angle using a 3D GRE MTC strategically acquired gradient echo (STAGE) imaging approach.  ...  Acknowledgements This work was supported in part by grants from the National Natural Science Foundation of China  ... 
doi:10.1016/j.neuroimage.2020.116935 pmid:32413460 fatcat:wex52tnagvfjlov7vg23gro5pq

Quantitative T1, T2, and T2* Mapping and Semi-Quantitative Neuromelanin-Sensitive Magnetic Resonance Imaging of the Human Midbrain

Takashi Hashido, Shigeyoshi Saito, Heye Zhang
2016 PLoS ONE  
Neuromelanin-sensitive MRI was acquired using an optimized T 1 -weighted twodimensional (2D)-turbo spin-echo sequence.  ...  Here, we aimed to clarify the relationship between contrast of neuromelanin-sensitive magnetic resonance imaging (MRI) and MR relaxation times using T 1 , T 2 , and T 2 * mapping of the lower midbrain.  ...  Langley et al. utilized a 2D-dual gradient-echo sequence with MTC preparation pulse and obtained the CR in the SNc, which was 0.16 ± 0.02 [30] .  ... 
doi:10.1371/journal.pone.0165160 pmid:27768782 pmcid:PMC5074498 fatcat:mh5z3com6jbuvfp56jzcs3cvh4

Reproducibility Assessment of Neuromelanin-Sensitive Magnetic Resonance Imaging Protocols for Region-of-Interest and Voxelwise Analyses [article]

Kenneth Wengler, Xiang He, Anissa Abi-Dargham, Guillermo Horga
2019 bioRxiv   pre-print
Neuromelanin-sensitive MRI (NM-MRI) provides a noninvasive measure of the content of neuromelanin (NM), a product of dopamine metabolism that accumulates with age in dopamine neurons of the substantia  ...  In particular, most previous studies used relatively thick MRI slices (~3 mm), compared to the typical in-plane resolution (~0.5 mm) and to the height of the SN (~15 mm), to overcome technical limitations  ...  NM-MRI images were acquired using 4 different gradient 2D recalled echo 1 sequences with magnetization transfer contrast (2D GRE-MTC) (Chen et al., 2014).  ... 
doi:10.1101/781815 fatcat:clqu6inrznc3dmxsr33zjyyw3y

Nigral iron and neuromelanin studies in Parkinson´s disease

Antonio Martin Bastida, Paola Piccini
Parkinson's disease (PD) a neurodegenerative condition characterized by the reduction of the pigmented dopaminergic neurons of the substantia nigra pars compacta (SNc) and the loss of the dopaminergic  ...  In this thesis I have used state of the art neuroimaging to assess nigral iron accumulation and nigral depigmentation in PD, the correlation between neuromelanin decline and nigrostriatal terminal loss  ...  Acknowledgements The study was funded by The Imperial NIHR Biomedical Research Centre (BRC). Deferiprone and its matched placebo were a generous cost free gift from ApoPharma Inc., Canada.  ... 
doi:10.25560/77826 fatcat:goknhanhfvbi3jkvturtkdgf6e

Surrogate markers of progression in Parkinson disease: Correlation between clinical features and neuroimaging

Marguerite Wieler
Increased levels of iron in the substantia nigra are seen in Parkinson disease although the mechanistic significance is uncertain.  ...  Loss of dopaminergic neurons in the substantia nigra of the basal ganglia is the prominent pathology associated with many of the motor features that characterise Parkinson disease.  ...  Acknowledgements The authors thank the subjects for their willing cooperation and Richard Camicioli for his critical comments. The authors have no competing interests.  ... 
doi:10.7939/r3rb6w728 fatcat:ixsukfqvyrarthfklorrcpqhoi

ACNP 57th Annual Meeting: Poster Session III

2018 Neuropsychopharmacology  
In a previous study, we developed the SASP (Senescence-Associated Secretory Phenotype) index, which is a composite measure of biomarkers related to senescence processes and can be viewed as an indicator  ...  Finally, the dysregulation of senescence-related biological cascades can provide a molecular link between depression and accelerated brain and systemic aging across the lifespan.  ...  The MR imaging data were obtained using a 3T scanner by a three-dimensional fast-spoiled gradient recalled acquisition with steady state.  ... 
doi:10.1038/s41386-018-0268-5 fatcat:wiooxnisvfhovadauljiso4ie4

ACNP 59th Annual Meeting: Poster Session III

2020 Neuropsychopharmacology  
In vivo pharmacokinetic studies are then used to measure plasma and brain exposures to guide the dose range and pretreatment times for the side effect profile, in vivo efficacy, and in vivo abuse liability  ...  Changes in the underlying neural circuitry in anxiety and hypervigilance can be probed clinically in humans through use of the Fearful Face Task (FFT) in fMRI studies.  ...  Our imaging protocol was optimized to separately localize dopaminergic nuclei (substantia nigra, ventral tegmental area, SN/VTA) and the noradrenergic locus coeruleus (LC-NE), both of which have been theoretically  ... 
doi:10.1038/s41386-020-00892-5 pmid:33279936 pmcid:PMC7735201 fatcat:mip4ywutfnfwvmye4u65i6vgg4

Modelling functional processes of brain tissue [article]

Αμαλία Ντέμου, University Of Ioannina, University Of Ioannina
The anatomical image series of each participant was acquired with the use of 3D spoiled gradient-echo sequence and a gradient echo planar imaging sequence was used to collect functional images.  ...  A high resolution three-dimensional spoiled gradient echo sequence, a spin-echo sequence and a gradient echo sampling of free induction decay and echo sequence were used to obtain structural imaging (T1  ... 
doi:10.26268/heal.uoi.3030 fatcat:jeaww55uurhtrdqmph5q4aq7lu

In vivo assessment of pathology in Parkinson's disease with Positron Emission Tomography

Benjamin Simpson, David Brooks, Parkinson's UK
in the striatum in the non-demented PD group compared to controls, with a predilection for posterior cortical structures. [11C]-PIB uptake had increased in the non-demented PD group at interval scanning  ...  . [11C]-PIB retention in the PD dementia group was higher than in the non-demented PD group, with a relative excess of anterior cortical [11C]-PIB binding.  ...  Gait characteristics Scans T1-weighted MRI scans were acquired using a 3T Philips Intera Achieva scanner with a magnetization-prepared rapid gradient echo sequence (MPRAGE). [ 18 F]-FDG PET scans were  ... 
doi:10.25560/53931 fatcat:2jooa7pbrvbfznhnn5iu6ww42y