Inflammatory and toxic lesions of the white matter in adult patients

Inflammatory and toxic lesions of the white matter can have the same or very similar radiological appearances, despite their different etiology. Differential diagnosis therefore is very difficult in many cases if based only on the analysis of the radiological morphology, neglecting the potential of additional neurological examinations like spinal fluid examination for example. Advanced diagnostic imaging methods available today, in this context primarily magnetic resonance imaging (MRI), however offer information that considerably reduces the range of possibly relevant differential diagnoses to be considered. The radiologist therefore has a key role in diagnostic evaluation. The paper describes the radiological appearances of the most important lesions of the adult white matter that are not induced by ischemia or neoplasms and discusses their particular patterns in respect of a differential diagnosis, explaining the valence and performance of the advanced imaging methods such as diffusion-MRI, perfusion-MRI, and magnetization-transfer-contrast-enhanced MRI. (orig./CB)