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Updated: Jul 14, 2026
05:12
Portable Thermographic Screening for Detection of Acute Wallenberg's Syndrome
Published on: September 19, 2019
[Wallerian degeneration after stroke: a new prognostic factor?]
João Soares-Fernandes1, Pedro Beleza, Manuel Ribeiro
1Serviços de Neurorradiologia e de Neurologia, Hospital de São Marcos, Braga.
Acta Medica Portuguesa
|June 23, 2007
Summary
Wallerian degeneration (WD) following ischemic stroke is detectable via diffusion-weighted imaging within two weeks. This early detection on MRI aids in predicting motor recovery and avoids misinterpretation as new ischemic lesions.
Area of Science:
- Neurology
- Radiology
- Neuroimaging
Background:
- Wallerian degeneration (WD) is linked to persistent motor deficits after ischemic stroke.
- Conventional MRI typically shows WD signal changes over four weeks post-stroke.
Observation:
- A 54-year-old male presented with acute left hemiparesis due to a right middle cerebral artery infarct.
- MRI at 13 days revealed the infarct and restricted diffusion in the ipsilateral corticospinal tract.
Findings:
- Wallerian degeneration (WD) was evident on diffusion-weighted imaging (DWI) within two weeks of stroke onset.
- This contrasts with conventional MRI, which shows changes much later.
Implications:
- Early WD detection using DWI allows for improved prognostic evaluation of motor recovery after stroke.
- Abnormal DWI signals in WD should not be mistaken for new ischemic events.
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