Apparent diffusion coefficient restriction in the white matter: going beyond acute brain territorial ischemia

Area of Science:

• Neuroradiology
• Neuroimaging
• White Matter Diseases

Background:

• Reduced apparent diffusion coefficient (ADC) values in white matter are not exclusively indicative of ischemic events.
• This phenomenon can be associated with a spectrum of non-ischemic neurological conditions.

Purpose of the Study:

• To identify and characterize diverse neuroradiological findings associated with reduced white matter ADC values.
• To differentiate these findings from ischemic white matter injury.

Main Methods:

• Retrospective analysis of MRI records.
• Focus on centrum semiovale white matter with reduced ADC values, excluding grey matter involvement and significant vasogenic edema.

Main Results:

• Identified specific MRI patterns for various conditions: X-linked Charcot-Marie-Tooth disease (moose-horn lesions), Menkes disease (fronto-parietal lesions), maple syrup urine disease (neonatal form), glutaric aciduria type 1 (corpus callosum involvement), phenylketonuria (periventricular parieto-occipital abnormalities).
• Other findings included global cerebral anoxia/heroin inhalation (diffuse abnormalities with necrosis), methotrexate neurotoxicity (reversible fronto-parietal lesions), watershed ischemia (chain-like lesions), reversible splenial lesions, and diffuse axonal injury (splenium involvement).

Conclusions:

• Familiarity with these varied MRI features is essential for neuroradiologists.
• Accurate interpretation prevents misdiagnosis and ensures appropriate clinical management of non-ischemic white matter abnormalities.