MS Lesion Visualization Assisted Segmentation

Daniel BiedigerCOSC 6397 – Scientific Visualization

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Multiple Sclerosis

• Autoimmune disease of the central nervous system• Affects 2.5 million people globally, ~100 per 100,000• Damage to the insulating myelin sheaths around brain cells• Appears as a range of cognitive and physical disability • Progresses at different rates with remission and relapse

Myelin: ~40% water, ~40-50% lipids

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Multiple Sclerosis

• Identified in-vivo with MRI images• Normally 3 tissues: GM, WM, CSF (SG, SB, LCR)• Lesion appear hyper- or hypo-intense (bright or dark)– Reflects a difference in relaxation times for lipids/water– Detected as an outlier to the normal WM– FLAIR MRI (Fluid Attenuated Inversion Recovery) best

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MS Detection Challenges

• WM Lesion detection is a challenge– Overlap in intensity between tissue classes– 3D brain structure (sulcus, ventricles, multiple tissues)– Partial Volume Effects (PVE)– Artifacts from fluid/patient motion, tumors, etc– Random noise, bias field, sun spots, etc

• Requires an expert to identify lesions– Tissue identification (T1-weighted MRI)– Lesion detection (FLAIR MRI)– Time consuming, difficult (multi-modality), and subjective

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MS Lesion Appearance in Flair

This?

This?

This?

or

or

Is this?

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Result Comparison

Under Segmentation

Correct Segmentation

Over Segmentation

DICE = 0.65

FLAIR MRI Base Method Expert Me

Results

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Project Timeline

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Questions

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