Related Experiment Video
Updated: Jan 15, 2026

Magnetic Resonance Imaging of Multiple Sclerosis at 7.0 Tesla
Published on: February 19, 2021
Automated segmentation of multiple sclerosis lesions, paramagnetic rims, and central vein sign on MRI provides
Fengling Hu1, Zheng Ren1, Luyun Chen1
1Penn Statistics in Imaging and Visualization Endeavor (PennSIVE), Department of Biostatistics, Epidemiology, and Informatics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States.
Abstract:
Multiple sclerosis (MS) is characterized by central nervous system lesions detectable via MRI. Existing diagnostic criteria incorporate presence of white matter lesions, but specificity can be improved using MS-specific imaging biomarkers, including paramagnetic rim lesions (PRLs) and central vein sign (CVS). However, manual segmentation of lesions, PRLs, and CVS is time-consuming and subjective. We propose a fully-automated joint segmentation method called Automated Lesion, PRL, and CVS Analysis (ALPaCA). We trained ALPaCA using subject-level cross-validation on 47 adults with MS and 50 adults with radiological MS mimics. ALPaCA uses a voxel-wise lesion segmentation method to propose a large set of lesion candidates. Lesion candidates are input into a multi-contrast, multi-label 3D convolutional neural network as 3D patches to produce lesion, PRL, and CVS predictions. When multiple lesions exist within a patch, an attention mechanism identifies which lesion candidate to classify. At the lesion level, ALPaCA achieves cross-validation areas under the receiver operating characteristic curve (AUROCs) of 0.95, 0.91, and 0.87 for lesion, PRL, and CVS classification, outperforming previous methods (all p < 0.001). Correlations between subject-level ALPaCA lesion and PRL scores with manual counts are higher than those of previous methods (p < 0.001; p = 0.03). Subject-level ALPaCA PRL and CVS scores are highly associated with MS in logistic regressions, when controlling for age and sex (p < 0.001). ALPaCA allows for fully-automated simultaneous segmentation of MS lesions, PRLs, and CVS using clinically-feasible scans. These segmentations outperform existing methods at the lesion and subject level.
Insights
A new automated method, ALPaCA, accurately segments multiple sclerosis (MS) lesions, paramagnetic rim lesions (PRLs), and the central vein sign (CVS) on MRI scans. This tool improves diagnostic accuracy and efficiency for MS detection.
Area of Science:
- Neuroimaging
- Artificial Intelligence in Medicine
- Neurology
Background:
- Multiple sclerosis (MS) diagnosis relies on detecting central nervous system lesions via MRI.
- Current criteria can be improved by incorporating MS-specific imaging biomarkers like paramagnetic rim lesions (PRLs) and central vein sign (CVS).
- Manual segmentation of these features is time-consuming and subjective, hindering clinical application.
Purpose of the Study:
- To develop and validate a fully-automated method for simultaneous segmentation of MS lesions, PRLs, and CVS.
- To improve the accuracy and efficiency of MS diagnosis using advanced neuroimaging analysis.
- To overcome the limitations of manual segmentation in clinical practice.
Main Methods:
- Developed Automated Lesion, PRL, and CVS Analysis (ALPaCA), a joint segmentation method.
- Trained ALPaCA using subject-level cross-validation on 47 adults with MS and 50 with MS mimics.
- Employed a 3D convolutional neural network with an attention mechanism for lesion, PRL, and CVS prediction from multi-contrast MRI scans.
Main Results:
- ALPaCA achieved high cross-validation AUROCs: 0.95 for lesions, 0.91 for PRLs, and 0.87 for CVS, outperforming previous methods (p < 0.001).
- Subject-level ALPaCA scores showed higher correlations with manual counts for lesions and PRLs compared to existing methods (p < 0.001; p = 0.03).
- ALPaCA's PRL and CVS scores were highly associated with MS diagnosis in logistic regressions (p < 0.001).
Conclusions:
- ALPaCA enables fully-automated, simultaneous segmentation of MS lesions, PRLs, and CVS using clinically feasible MRI scans.
- The automated segmentations demonstrate superior performance at both lesion and subject levels compared to current methods.
- This technology has the potential to enhance the accuracy and efficiency of MS diagnosis and monitoring.
More Related Videos
12:50Lesion Explorer: A Video-guided, Standardized Protocol for Accurate and Reliable MRI-derived Volumetrics in Alzheimer's Disease and Normal Elderly
Published on: April 14, 2014
10:25Brain Infarct Segmentation and Registration on MRI or CT for Lesion-symptom Mapping
Published on: September 25, 2019