Diffusion-weighted imaging of Wallerian degeneration in non-accidental head injury

Abstract

An 11-month-old infant with clinical, ophthalmological and radiological findings (including intracranial haemorrhage) of 24–72 h estimated duration, consistent with non-accidental injury showed hyperintense signal on diffusion-weighted imaging (DWI) and decreased apparent diffusion coefficient (ADC) in the cerebral cortex, including the motor cortex, bilaterally, indicating cytotoxic oedema (Fig. 1). There was no abnormality in the cerebral peduncles. Follow-up MRI 18 days later showed DWI hyperintensity and decreased ADC in the cerebral peduncles and evolving infarct (T2-W/FLAIR hyperintensity and parenchymal loss) in the motor cortex (Fig. 2). These observations were interpreted as Wallerian degeneration.