CT findings in persistent vegetative state following blunt traumatic brain injury

The use of linear measurements in the analysis of CT scans of TBI patients was found to contribute to the understanding of brain damage and were correlated with outcome in severe traumatic close brain injured patients. The purpose of the present study was to analyse the data obtained by the linear measurements on CT studies of TBI patients who remained in persistent vegetative state following blunt head trauma. All 27 patients included in the study were reported to be neurologically normal prior to injury. Thirteen patients, 11 remaining in persistent vegetative state (responsive but unaware) and two who died, constituted the worst outcome group. Fourteen patients who regained consciousness, underwent multidisciplinary evaluation when their recovery reached a plateau and were ranked according to severity of residual symptoms and outcome. The degree of correlation with the overall vocational outcome parameter with the various radiological indices was calculated as the Spearman rank correlation coefficient, with correction for tied scores. Fisher's z transformation was used to combine results with those of our previous analysis. Three radiological parameters showed a statistically significant correlation with clinical outcome. These were the right and left septum-caudate distance and the cerebroventricular index 2; these showed Spearman rank coefficients of 0.52, 0.45 and 0.48; with two-tailed p-values under 0.01, 0.02 and 0.01 respectively. The width of the third ventricle suggested correlation with the clinical scoring. The findings of the present study point to the importance of loss of deep gray matter of the caudate nuclei and widening of the adjacent part of the lateral ventricles in catastrophic brain injury. This finding may highlight the role of localized ischemic changes, in addition to diffuse axonal injury. Values of over 8 mm for the width of the third ventricle and over 11 mm for septum caudate distance are suggestive of catastrophic and poor prognosis for recovery.