Magnetic resonance imaging finding in severe head injury patients with normal computerized tomography

Computerized tomography (CT) has been the primary diagnostic instrument of neurosurgical centers for head injury until now. However, there is a subgroup of patients who have persisting neurological deficits without visible pathology on CT.

Between 2000 and 2002, 3000 patients were enrolled in this prospective study in emergency unit. There was a total of 124 patients (4.1%) who had persisting severe neurological deficits with normal findings on repeated CT scans. These patients underwent 1.5 Tesla cranial MRI study between posttraumatic days 2 and 10 (5.2+/-4.5). Data on epidemiological, clinical, radiological factors and final outcome were collected.

76 (61.2%) of the patients were male and 48 (38.7%) were female. 113 (91.1%) of the 124 patients showed significant primary pathology on MRI study. The most common pathology was shear injuries in 75 (60.4%) followed by cortical contusion in 45 (36.2%) cases. 27 (21.7%) patients showed primary brain stem lesions and 8 (0.6%) patients showed subcortical gray matter lesions. 32 patients showed mixed lesions. There was one traumatic aneurysm detected.

The MRI examination in head injury is informative in detecting subtle lesions when the neurological condition cannot be explained by CT.