Diffuse axonal injury (DAI) is widespread damage to axons in the white matter of the hemispheres and brain stem. Axonal damage was produced by mechanical forces shearing the fibers at the moment of impact. The paper present four patients. Of these three were injured in a road traffic accident. The true extent of brain involvement is better appreciated with MR imaging. MR imaging in our patients demonstrated multiple focal lesions of the white matter of the cerebral hemisphere (centrum semiovale, corpus callosum) and the brain stem (midbrain and pontine tegmentum, substantia nigra, cerebral peduncles and the dorsolateral quadrant of the pontomesencephalic transition).

        Key words: head trauma - traumatic brain injury - magnetic resonance