The results of this systematic review identify the consistent and prevalent indicators of concussion and their associations , derived from the strongest evidence in the published literature .
BACKGROUND Currently , there is no evidence -based definition for concussion that is being uniformly applied in clinical and research setting s. OBJECTIVE To conduct a systematic review of the highest- quality literature about concussion and to assemble evidence about the prevalence and associations of key indicators of concussion .
The goal was to establish an evidence -based foundation from which to derive , in future work , a definition , diagnostic criteria , and prognostic indicators for concussion .
Diagnosing mild traumatic brain injury: where are we now?
BACKGROUND The brain acoustic monitor ( BAM ) , an indicator of cerebral autoregulation , has previously shown high sensitivity but low specificity for computed tomographic ( CT ) abnormality in patients following the clinical diagnosis of traumatic brain injury . We assessed the utility of the BAM in diagnosing mild TBI ( mTBI ) in patients with and without normal findings of CT scan , a population for which there are a few objective markers of disease . METHODS We prospect ively studied 369 patients with mechanism of injury consistent with TBI . The diagnosis was evaluated by five methods : ( a ) study enrollment ( i.e. , mechanism of injury ) , ( b ) signs of head trauma , ( c ) expert physician assessment , ( d ) presence of initial symptoms (  loss of consciousness  [ LOC ] ; amnesia ) , and ( e ) BAM .  All patients had a head CT scan . We compared the BAM screen results with the diagnosis of mTBI and BAM data from 50 normal volunteers and 49 trauma control patients not thought to have TBI . RESULTS None of the diagnostic methods correlated well with the others . Correlation between the methods ranged from 21 % to 71 % . BAM discriminated between patients with mTBI versus without TBI ( p<0.01 ) and patients with mTBI versus normal subjects ( p<0.001 ) . There were 14 patients with new abnormal findings of CT scans . A history of LOC and physical signs of head injury were associated with a new abnormality on head CT ( p<0.05 and p<0.01 , respectively ) , whereas an abnormal BAM signal was suggestive ( p=0.08 ) . The sensitivity of BAM abnormality for head CT abnormality was 100 % , with a specificity of 30.14 % . CONCLUSION There is no gold st and ard for the diagnosis of mTBI . BAM screening is a useful diagnostic adjunct in patients with mTBI and may facilitate decision making . An abnormal BAM reading adds significance to LOC as a predictor of a new abnormality on head CT . In our study , opting not to CT scan patients with a normal BAM signal would have missed no new CT findings and no patients who required medical intervention for TBI , at a cost savings of $ 202,950
The results of this systematic review identify the consistent and prevalent indicators of concussion and their associations , derived from the strongest evidence in the published literature .
BACKGROUND Currently , there is no evidence -based definition for concussion that is being uniformly applied in clinical and research setting s. OBJECTIVE To conduct a systematic review of the highest- quality literature about concussion and to assemble evidence about the prevalence and associations of key indicators of concussion .
The goal was to establish an evidence -based foundation from which to derive , in future work , a definition , diagnostic criteria , and prognostic indicators for concussion .