Three patients with pretraumatic and posttraumatic brain injury (TBI) MR imaging of the brain are presented. Two patients had moderate to severe injury, whereas the third patient sustained a mild injury. Using imaging software to conduct morphometric analyses, quantitative neuropathologic change was ascertained in each TBI patient. Each case was compared quantitatively to preinjury scans as well as to an age-matched control group. For the moderately to severely injured patients, extensive degenerative changes were found throughout the various cortical structures and the cerebellum, whereas most midbrain and brainstem measures did not demonstrate significant change. For these two patients, the most significant changes occurred within the ventricular system, where generalized ventricular dilation was observed post-TBI. In the mild case, no significant anatomic changes were evident. These case studies demonstrate the use of quantitative methods for examining the structural basis of TBI sequelae.