[en] One hundred and fifty-nine patients admitted for mild or moderate head injuries were studied in order to establish the advantage of magnetic resonance imaging (MRI) over computerized tomography (CT) in the acute stage. One hundred and twenty-three lesions were demonstrated by MRI in 106 patients. In contrast, CT demonstrated only 74 lesions in 76 patients. The advantage of MRI over CT in the imaging of these lesions was remarkable in cases of basal skull fractures or lesions in the cerebral parenchyma, especially in case of non-hemorrhagic contusions or focal brain edemas. MRI was superior to CT in demonstrating these lesions in 64 patients of our series. However, in 6 cases of subarachnoid hemorrhage located in the Sylvian fissure, CT was superior to MRI. It was thought that lesions were less commonly demonstrated by CT in cases of mild or moderate head injuries. However, many lesions were confirmed by MRI in these cases. MRI was thus found to be far superior to CT in demonstrating intracranial lesions in mild or moderate head injuries. (author)