CT FINDINGS IN PERSISTENT VEGETATIVE STATE FOLLOWING BLUNT TRAUMATIC BRAIN INJURY

The use of linear measurements in the analysis of CT scans of TBI pati ents was found to contribute to the understanding of brain damage and were correlated with outcome in severe traumatic close brain injured p atients. The purpose of the present study was to analyse the data obta ined by the linear measurements on CT studies of TBI patients who rema ined in persistent vegetative state following blunt head trauma. AU 27 patients included in the study were reported to be neurologically nor mal prior to injury. Thirteen patients, 11 remaining in persistent veg etative state (responsive but unaware) and two who died, constituted t he wont outcome group. Fourteen patients who regained consciousness, u nderwent multidisciplinary evaluation when their recovery reached a pl ateau and were ranked according to severity of residual symptoms and o utcome. 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 statisti cally significant correlation with clinical outcome. These were the ri ght and left septum-caudate distance and the cerebroventricular index 2; these showed Spearman rank coefficients of 0.52, 0.45 and 0.48; wit h two-tailed p-values under 0.01, 0.02 and 0.01 respectively. The widt h of the third ventricle suggested correlation with the clinical scori ng. 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 fin ding may highlight the role of localized ischemic changes, in addition to diffuse axonal injury. Values of over 8 mm for the width of the th ird ventricle and over 11 mm for septum caudate distance are suggestiv e of catastrophic injury and poor prognosis for recovery.