[Assessing and predicting recovery from a coma following traumatic brain injury: contribution of neuroradiological data].
OBJECTIVE
Literature review concerning the contribution of neurological imaging to the assessment of traumatic lesions and the prognosis of traumatic coma.


METHODS
Interrogation of scientific databases Medline, Embase and Current Contents via key-words. One hundred and seventy-one articles were picked up out of which 67 were analysed according to the French ANAES' rules. Results and discussion are drawn from the literature data and the author's experience.


CONCLUSIONS
In the acute stage the diagnosis approach prevails the prognostic dimension, is confused by secondary complications. Computerized-Tomography (CT) remains the best imaging modality, allowing a quick diagnosis of most of injuries, especially those which require an emergency treatment. But its predictive value in coma outcome is low. Although magnetic resonance imagery (MRI) is more sensitive, it does not at the acute stage lead to therapeutic modifications, increases the costs and is thus not necessary. MRI angiography may show cranial vessel injury which need specific therapeutic procedures. In the subacute or chronic stage after a severe head injury, CT is useful for the follow up and may provide some prognostic informations. But MRI with classical sequences has a higher sensitive and predictive power. Diffusion weighted imaging has not so far made the proof of it's predictive value. Proton MR spectroscopy seems to be able to provide data correlated with neurological outcome (NAA/Cr), but is not of routine use. Single-photon emission tomography is also useful to assess brain injury sequelae in the chronic stage; positron-emission tomography still remains a research technology. These 2 modalities have not yet a prognostic value.


CONCLUSIONS
In the acute stage CT remains the best imaging modality. In the subacute and chronic stage MRI has the highest predictive power. Special sequences raise new hopes. Single-photon emission tomography and positron-emission tomography have not yet a prognostic value.
Solacroup
J C
JC
Service d'imagerie médicale, hôpital d'instruction des armées Sainte-Anne, 83800 Toulon Naval, France. jcsolacroup@libertysurf.fr
Tourrette
J H
JH
D001930:Brain Injuries / Q000150:complications* / Q000473:pathology / Q000534:rehabilitation*; D003128:Coma / Q000209:etiology / Q000473:pathology / Q000534:rehabilitation*; D006801:Humans; D018810:Magnetic Resonance Angiography; D008279:Magnetic Resonance Imaging; D011237:Predictive Value of Tests; D011379:Prognosis; D014057:Tomography, X-Ray Computed