Presented During:
Friday, June 27, 2025: 11:30 AM - 12:45 PM
Brisbane Convention & Exhibition Centre
Room:
M4 (Mezzanine Level)
Poster No:
1934
Submission Type:
Abstract Submission
Authors:
Charlotte Pretzsch1, Frantisek Váša2, Michael Brammer1, Lucy Brink3, Cindy Pham1, Hein Odendaal4, Dan Stein5, Elizabeth Sowell6, Priscilla Springer7, Eva Loth1, Declan Murphy1, Christine Ecker8
Institutions:
1Dept of Forensic and Neurodevelopmental Sciences, King's College London, London, United Kingdom, 2Dept of Neuroimaging, Institute of Psychiatry, Psychology, and Neuroscience, King’s College London, London, United Kingdom, 3Dept of Obstetrics and Gynaecology, Stellenbosch University, Stellenbosch, South Africa, 4Dept of Obstetrics and Gynaecology, Stellenbosch University, South Africa, Stellenbosch, South Africa, 5Dept of Psychiatry and Mental Health, University of Capetown, Capetown, South Africa, 6Dept of Paediatrics, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA, 7Dept of Paediatrics and Child Health, Stellenbosch University, Stellenbosch, South Africa, 8Dept of Child and Adolescent Psychiatry, Psychosomatics, Psychotherapy, Goethe-University Frankfurt, Frankfurt, Germany
First Author:
Charlotte Pretzsch
Dept of Forensic and Neurodevelopmental Sciences, King's College London
London, United Kingdom
Co-Author(s):
Frantisek Váša
Dept of Neuroimaging, Institute of Psychiatry, Psychology, and Neuroscience, King’s College London
London, United Kingdom
Michael Brammer
Dept of Forensic and Neurodevelopmental Sciences, King's College London
London, United Kingdom
Lucy Brink
Dept of Obstetrics and Gynaecology, Stellenbosch University
Stellenbosch, South Africa
Cindy Pham
Dept of Forensic and Neurodevelopmental Sciences, King's College London
London, United Kingdom
Hein Odendaal
Dept of Obstetrics and Gynaecology, Stellenbosch University, South Africa
Stellenbosch, South Africa
Dan Stein
Dept of Psychiatry and Mental Health, University of Capetown
Capetown, South Africa
Elizabeth Sowell
Dept of Paediatrics, Keck School of Medicine, University of Southern California
Los Angeles, CA, USA
Priscilla Springer
Dept of Paediatrics and Child Health, Stellenbosch University
Stellenbosch, South Africa
Eva Loth
Dept of Forensic and Neurodevelopmental Sciences, King's College London
London, United Kingdom
Declan Murphy
Dept of Forensic and Neurodevelopmental Sciences, King's College London
London, United Kingdom
Christine Ecker
Dept of Child and Adolescent Psychiatry, Psychosomatics, Psychotherapy, Goethe-University Frankfurt
Frankfurt, Germany
Introduction:
Conventional, high-field (3 Tesla) magnetic resonance imaging can provide crucial insights into brain structure and function but remains limited to high-resource settings. Novel, low-field (<0.1T) imaging techniques offer a more cost-effective, accessible alternative (1). However, to harness their potential, including in low- and middle-income countries (LMIC), we first need to establish the validity of low-field data at spatial resolutions relevant to research and clinic (including at the vertex-level); and this was the aim of the present study.
Methods:
We acquired paired high-field and low-field neuroimaging data from 12 children aged 10–12 years in a LMIC (interscan interval <6 months). High-field images, processed using standard neuroimaging toolkits, served as reference. Low-field images (either single-orientation scans or multiple orthogonal orientations combined into one scan), were analysed with and without prior image enhancement, and processed using a range of established and novel processing pipelines. We assessed correspondence between high-field and low-field vertex-level measures of cortical volume, surface area, and cortical thickness using correlation-based techniques (Pearson correlation, Intraclass Correlation Coefficient, and Lin's Concordance Correlation Coefficient); and compared processing strategies using Pearson correlation, mixed-effects models, and Steiger's Z-tests.

·Figure 1: Study schematic
Results:
Across analytic strategies, high-field and low-field images showed weak to moderate global correspondence (cortical volume and surface area: Pearson's r≤0.6, cortical thickness r≤0.3), and weak to very strong local correspondence (r≤0.99). Greatest correspondence was achieved with multi-orientation images using either a pipeline adjusted for low-resolution images (recon-all-clinical) or a combination of image enhancement (SynthSR) and a standard imaging toolbox (FastSurfer); but agreement varied across brain regions based on input data, analytic strategy, and neuroanatomical feature. To increase the impact of our research, we have developed an application that enables the user to interactively view and access our results – e.g., to download spatial masks of brain regions with a particularly high low-field/high-field correspondence for a specified processing pipeline and neuroanatomical feature.
Conclusions:
Our results extend prior research by demonstrating that low-field imaging can provide reliable, high-resolution estimates of cortical volume and surface area, but not cortical thickness. The choice of analytic approach should be guided by multiple considerations, including e.g., the brain region of interest and available data and computational resources; and the application we have developed may support this selection. Once validated in larger and more heterogeneous cohorts, this research may pave a way towards deploying low-field imaging as a powerful toolkit to aid research and evidence-based clinical work in high- and low-resource settings, including in LMICs.
Modeling and Analysis Methods:
Methods Development 2
Motion Correction and Preprocessing
Neuroanatomy, Physiology, Metabolism and Neurotransmission:
Cortical Anatomy and Brain Mapping
Neuroinformatics and Data Sharing:
Workflows
Novel Imaging Acquisition Methods:
Imaging Methods Other 1
Keywords:
Acquisition
Cortex
Data analysis
MRI
STRUCTURAL MRI
Other - Low-field MRI
1|2Indicates the priority used for review
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Please indicate below if your study was a "resting state" or "task-activation” study.
Other
Healthy subjects only or patients (note that patient studies may also involve healthy subjects):
Healthy subjects
Was this research conducted in the United States?
No
Were any human subjects research approved by the relevant Institutional Review Board or ethics panel?
NOTE: Any human subjects studies without IRB approval will be automatically rejected.
Yes
Were any animal research approved by the relevant IACUC or other animal research panel?
NOTE: Any animal studies without IACUC approval will be automatically rejected.
Not applicable
Please indicate which methods were used in your research:
Structural MRI
Other, Please specify
-
Low-field MRI
For human MRI, what field strength scanner do you use?
3.0T
If Other, please list
-
low-field (64mT)
Which processing packages did you use for your study?
Free Surfer
Other, Please list
-
FastSurfer, SynthSR, SynthSeg
Provide references using APA citation style.
Vasa, F. (under review). Ultra-low-field brain MRI morphometry: test-retest reliability and correspondence to high-field MRI.
No