Single photon emission computed tomography scanning: A predictor of outcome in vegetative state of head injury

Neurotrauma is one of the most important causes of death and disability. Some of the severely head injured patients, failed to show significant improvement despite aggressive neurosurgical management and ended up in a vegetative state.

To assess the outcome at six months and one year using Glasgow outcome scale (GOS), in this prospective study on patients with severe head injury, who remained vegetative at one month.

This prospective study was carried out in the department of Neurosurgery, All India Institute of Medical Sciences (AIIMS), New Delhi, over a period of a year and a half (March 2002 through July 2003).

In patients with severe head injury (GCS < 8), post resuscitation, neurological assessment was done with Glasgow coma scale (GCS), pupillary light reflex, doll's eye movement and cold caloric test in all cases. Fifty patients, who remained vegetative post injury according to the criteria of Jennett and Plum, at one month, were considered for the study. Brain SPECT (Single Photon Emission Computed T omography) Scanning was carried out in selected cases.

Data analysis was done by Pearson's chi-square test on computer software SPSS, Version 10 (California, USA).

Patients with preserved brainstem reflex and with no perfusion defect on SPECT scan had statistically significant favorable outcome. More than 40% of vegetative patients regained consciousness by the end of one year, of whom 24% had favorable outcome in the form of moderate disability and good recovery.

SPECT is better than computed tomography/magnetic resonance imaging (CT/MRI) as it assesses the cerebral perfusion and functional injury rather than detecting the lesions only. Further study with a control group is necessary to establish the role of SPECT in head injury.