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Rasmussen syndrome: multifocal spread of inflammation suggested from MRI and PET findings
Yumi Maeda1, Hirokazu Oguni, Yoshiaki Saitou
1Department of Pediatrics, Tokyo Woman's Medical University, Tokyo, Japan.
Background:
A 6-year-old girl with Rasmussen syndrome (RS) showed multiple small high-signal-intensity areas independently in the right hemisphere by fluid-attenuated inversion recovery (FLAIR) imaging on magnetic resonance imaging (MRI) 1 year after the onset of epilepsy.
Methods:
MRI performed 4 months later demonstrated a further increase in the number of these foci and enlargement in the size of the previous FLAIR lesions.
Results:
An [18F]-fluorodeoxyglucose-positron emission tomography (FDG-PET) study showed a strong, spotty uptake in the right temporooccipital regions, corresponding to the sites of continuous EEG seizure discharges. In contrast, [11C]methionine PET demonstrated multifocal uptake regions, which corresponded anatomically to the FLAIR lesions, suggesting sites of underlying chronic inflammation.
Conclusions:
These neuroimaging findings suggested that the inflammatory process in RS spreads either multifocally at the same time, as seen in this case, or from one discrete area to the adjacent region, as reported previously.
Insights
Rasmussen syndrome (RS) can spread multifocally, as shown by MRI and PET scans revealing inflammation in a child. These neuroimaging findings highlight the varied inflammatory patterns in RS.
Area of Science:
- Neurology
- Neuroimaging
- Pediatric Epilepsy
Background:
- Rasmussen syndrome (RS) is a rare, chronic inflammatory neurological disease affecting one cerebral hemisphere.
- Early diagnosis and understanding of disease progression are crucial for effective management.
Observation:
- A 6-year-old girl with RS presented with new lesions on MRI (magnetic resonance imaging) FLAIR (fluid-attenuated inversion recovery).
- Follow-up MRI showed increased lesion number and size, indicating disease progression.
- EEG (electroencephalography) revealed continuous seizure discharges in the right temporooccipital regions.
Findings:
- FDG-PET ( [18F]-fluorodeoxyglucose-positron emission tomography) showed high uptake in areas of seizure activity.
- [11C]methionine PET revealed multifocal uptake corresponding to MRI lesions, suggesting chronic inflammation.
- These findings indicate simultaneous multifocal inflammatory spread in RS.
Implications:
- The study suggests RS inflammation can spread multifocally or contiguously.
- Advanced neuroimaging techniques like PET-CT aid in understanding RS pathogenesis.
- This case broadens the understanding of RS inflammatory patterns and progression.
