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Why Voxel-Based Morphometry Should Be Used

John Ashburner, Karl J. Friston
2001 NeuroImage  
(ii) We agree with him when he states that findings from VBM can pertain to systematic registration errors during spatial normalization.  ...  Bookstein appears to have misunderstood the objective of voxel-based morphometry (VBM) and the nature of the continuum we referred to.  ...  ACKNOWLEDGMENTS Many thanks to the Dementia Research Group (Queen Square, London, UK) for the data shown in Fig. 1 . J.A. and K.J.F. are supported by The Wellcome Trust.  ... 
doi:10.1006/nimg.2001.0961 pmid:11707080 fatcat:dq5pbyaks5diff67h6cor6uccq

Statistical Assessment of Proton Treatment Plans Under Setup and Range Uncertainties

Peter C. Park, Joey P. Cheung, X. Ronald Zhu, Andrew K. Lee, Narayan Sahoo, Susan L. Tucker, Wei Liu, Heng Li, Radhe Mohan, Laurence E. Court, Lei Dong
2013 International Journal of Radiation Oncology, Biology, Physics  
To account for the dose under uncertainties, we performed a comprehensive simulation in which the dose was recalculated 600 times per given plan under the influence of random and systematic setup errors  ...  The organs with most sensitive dose under uncertainties were esophagus and spinal cord for lung, rectum for prostate, and brain stem for brain cancer.  ...  (a) Randomly selected systematic and random setup error coordinates for a selected patient; (b) CT number-to-relative stopping power curve for nominal and with systematic range error.  ... 
doi:10.1016/j.ijrobp.2013.04.009 pmid:23688812 pmcid:PMC3755369 fatcat:ymobhhkjbbbcnceyy5imkzxjsa

Implication of spot position error on plan quality and patient safety in pencil-beam-scanning proton therapy

Juan Yu, Chris J. Beltran, Michael G. Herman
2014 Medical Physics (Lancaster)  
error and its sensitivity to PE.  ...  Various perturbation scenarios of a single spot error and systematic and random multiple spot errors were studied.  ...  ACKNOWLEDGMENT The authors report no conflicts of interest in conducting the research. This work was supported in part by Varian Medical Systems.  ... 
doi:10.1118/1.4885956 pmid:25086516 fatcat:wvhyvio4brgflfylrxq33codae

High Frequency Ultrasound Versus Magnetic Resonance Imaging for The Volumetric Reconstruction of Brain Ventricles Following IVH in Preterm Rabbit Pups

Romantsik O, Erlov T, Russo C, Meirza B, Gottschalk M, Cinthio M, Ley D
2021 Journal of Clinical and Medical Images  
Ultrasound renders real-time bi-dimensional slices of the brain sensitive to movement and prone to error when attempting to repeat image acquisition at the same plane.  ...  Intra-observer reproducibility for MRI -based lateral ventricle volumetric measurement was similarly excellent with ICC being 0.997 (CI =0.994-0.998): systematic and random differences were 0.1 mm 3 and  ... 
doi:10.47829/jcmi.2021.5802 fatcat:wog5ig6frvdmzog25wkvdq3c24

Decline Variability of Cortical and Subcortical Regions in Aging: A Longitudinal Study

Silvano Sele, Franziskus Liem, Susan Mérillat, Lutz Jäncke
2020 Frontiers in Human Neuroscience  
This dataset enables us to gain new insights about volumetric cortical and subcortical changes and their associations in the context of healthy aging.  ...  Taken together, our study contributes to enhancing our understanding of structural brain aging by demonstrating (1) that average volumetric change differs across the brain and (2) that there are regional  ...  Measurement Error Term and Image Quality A large amount of the uncertainty in the random slope variances and covariances is due to the large within-subject error term.  ... 
doi:10.3389/fnhum.2020.00363 pmid:33100991 pmcid:PMC7500514 fatcat:coj4lg6vazb3riw4zozkxhyku4

Hybrid RGSA and Support Vector Machine Framework for Three-Dimensional Magnetic Resonance Brain Tumor Classification

R. Rajesh Sharma, P. Marikkannu
2015 The Scientific World Journal  
The experimental results demonstrate the systematic and efficient feature extraction and feature selection algorithm to the performance of state-of-the-art feature classification methods.  ...  MRI of brain under two classes of lesion, benign and malignant.  ...  Table 5 shows the average results computed for the proposed SVM classifier with that of BPN and NN with respect to specificity, sensitivity, accuracy, ROC, and mean square error.  ... 
doi:10.1155/2015/184350 pmid:26509188 pmcid:PMC4609875 fatcat:bf47vuv2obcddoxrpeerxqsus4

Understanding the impact of RapidArc therapy delivery errors for prostate cancer

Mike Oliver, Karl Bush, Sergei Zavgorodni, Will Ansbacher, Wayne A. Beckham
2011 Journal of Applied Clinical Medical Physics  
The purpose of this study is to simulate random and systematic RapidArc delivery errors for external beam prostate radiotherapy plans in order to determine the dose sensitivity for each error type.  ...  We found that random and systematic gantry position errors were relatively insignificant (< 0.1% gEUD change) for gantry errors up to 1°.  ...  (16) For dynamic (sliding window) MLC IMRT, Rangel and Dunscombe (17) performed an analysis of random and systematic MLC position errors for prostate cancer and head and neck cancer.  ... 
doi:10.1120/jacmp.v12i3.3409 fatcat:eck4hjmaz5gc7dtomlcmr6dnha

Understanding the impact of RapidArc therapy delivery errors for prostate cancer

Michael Oliver, Karl Bush, Sergei Zavgorodni, Will Ansbacher, Wayne A Beckham
2011 Journal of Applied Clinical Medical Physics  
The purpose of this study is to simulate random and systematic RapidArc delivery errors for external beam prostate radiotherapy plans in order to determine the dose sensitivity for each error type.  ...  We found that random and systematic gantry position errors were relatively insignificant (< 0.1% gEUD change) for gantry errors up to 1°.  ...  (16) For dynamic (sliding window) MLC IMRT, Rangel and Dunscombe (17) performed an analysis of random and systematic MLC position errors for prostate cancer and head and neck cancer.  ... 
pmid:21844850 pmcid:PMC5718657 fatcat:yvcagtskvnei7argkyg5qrf4du

Analysis of direct clinical consequences of MLC positional errors in volumetric-modulated arc therapy using 3D dosimetry system

Karthikeyan Nithiyanantham, Ganesh K. Mani, Vikraman Subramani, Lutz Mueller, Karrthick K. Palaniappan, Tejinder Kataria
2015 Journal of Applied Clinical Medical Physics  
Systematic errors of +1, +0.5, +0.3, 0, -1, -0.5, -0.3 mm were introduced in the MLC bank of the linear accelerator and the impact on the dose distribution of VMAT delivery was measured using the COMPASS  ...  We analyzed the impact of the MLC positional errors on the dose distribution for volumetric-modulated arc therapy, using a 3D dosimetry system.  ...  (6, 7) Most of the studies on MLC positional error -both random and systematic errors were analyzed -have reported that the random errors were insignificant, while systematic errors have shown significant  ... 
doi:10.1120/jacmp.v16i5.5515 pmid:26699311 pmcid:PMC5690184 fatcat:tc44ql3uorarrc7k4htztj6uoi

Reliability and validity of MRI-based automated volumetry software relative to auto-assisted manual measurement of subcortical structures in HIV-infected patients from a multisite study

Jeffrey Dewey, George Hana, Troy Russell, Jared Price, Daniel McCaffrey, Jaroslaw Harezlak, Ekta Sem, Joy C. Anyanwu, Charles R. Guttmann, Bradford Navia, Ronald Cohen, David F. Tate
2010 NeuroImage  
The automated volumetric output of FreeSurfer and Individual Brain Atlases using Statistical Parametric Mapping (IBASPM), two widely used and well published software packages, was examined for accuracy  ...  The data was examined for accuracy and consistency relative to auto-assisted manual tracing, and construct validity was assessed by correlating automated and AAM volumetric measures with relevant clinical  ...  We also acknowledge the support of the following funding sources: R01 NS036524 and K23 MH073416.  ... 
doi:10.1016/j.neuroimage.2010.03.033 pmid:20338250 pmcid:PMC2884380 fatcat:nsaawi6p6ncjjh6j4cpxw64n7e

Post-acquisition Processing Confounds in Brain Volumetric Quantification of White Matter Hyperintensities

Ahmed A. Bahrani, Omar M. Al-Janabi, Erin L. Abner, Shoshana H. Bardach, Richard J. Kryscio, Donna M. Wilcock, Charles D. Smith, Gregory A. Jicha
2019 Journal of Neuroscience Methods  
Considerations of potential sources-of-variability in MRI volume quantification techniques and reduction in such variability is imperative to allow for reliable cross-site and cross-study comparisons.  ...  Understanding and controlling for such sources-of-variability can reduce post-acquisition quantitative image processing variance to less than 0.5%.  ...  To allow assessment of potential variance that is associated with a differential selection of the CoG, two random CoGs were selected for each subject in addition to the systematic CoG.  ... 
doi:10.1016/j.jneumeth.2019.108391 pmid:31408649 pmcid:PMC6746343 fatcat:gmae77mo2bgbzltnft2qipuvhy

A random-effects model for group-level analysis of diffuse optical brain imaging

Farras Abdelnour, Theodore Huppert
2010 Biomedical Optics Express  
These factors can give rise to partial volume errors and loss of sensitivity and therefore must be accounted for in combining data from multiple subjects.  ...  In this work, we describe an image reconstruction approach using a parametric Bayesian model that simultaneously reconstructs group-level images of brain activity in the context of a random-effects analysis  ...  Acknowledgements This work was funded by startup funding by the University of Pittsburgh Department of Radiology and the National Institutes of Health (P30AG024827, R21NS064457, and R01AG029546)  ... 
doi:10.1364/boe.2.000001 pmid:21326631 pmcid:PMC3028484 fatcat:bzmwk4hhjbagzgl46nwgl43lqq

Lesion Induced Error on Automated Measures of Brain Volume: Data From a Pediatric Traumatic Brain Injury Cohort

Daniel J. King, Jan Novak, Adam J. Shephard, Richard Beare, Vicki A. Anderson, Amanda G. Wood
2020 Frontiers in Neuroscience  
Structural segmentation of T1-weighted (T1w) MRI has shown morphometric differences, both compared to controls and longitudinally, following a traumatic brain injury (TBI).  ...  insufficient for the global error in morphometric measures of the injured brain.  ...  This was to disentangle the volumetric differences due to injury and those due to the algorithmic error within the surface-based output of Freesurfer, likely induced by the erroneous signal within the  ... 
doi:10.3389/fnins.2020.491478 pmid:33424529 pmcid:PMC7793828 fatcat:5ct6xywsxfexpeiba3i6fmwpca

A role for the cerebellum in the control of verbal interference: Comparison of bilingual and monolingual adults

Roberto Filippi, Eva Periche Tomas, Andriani Papageorgiou, Peter Bright, Claudio Mulatti
2020 PLoS ONE  
We compare brain structure sensitivity to verbal interference control across two groups, English monolingual (N = 41) and multilingual (N = 46) adults.  ...  Using voxel-based morphometry, our primary goal was to identify and explore differences in regional patterns of grey matter sensitivity to performance on the sentence interpretation task, controlling for  ...  A special thought goes to Prof. Annette Karmiloff-Smith who inspired our research.  ... 
doi:10.1371/journal.pone.0231288 pmid:32315339 fatcat:ohbj6btf3fbwnpbpexs4iu3na4

PD-0379: Reducing the dose-rate dependence of a new radiochromic silicone based 3D dosimeter

E. Høye, P. Balling, L.P. Muren, J.B.B. Petersen, E. Yates, P. Skyt
2015 Radiotherapy and Oncology  
The average random error was of 2.4, 4.5 and 2.2 mm.  ...  The range shifts were also retrieved from the comparison of 2 Gy and 60 Gy acquisitions in order to evaluate an occurrence of the random errors.  ...  Figure: Treatment plan (top-left), experimental setup (topright) , and range analysis on first energy layer (bottom): (a) range sensitivity to energy variations of +/-3 MeV on first layer; (b) systematic  ... 
doi:10.1016/s0167-8140(15)40375-5 fatcat:uzvktkqd2rdnddpl5pyfflugg4
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