Published in IJCP March 2020
Short communication
Brain Activation In Unresponsive Patients With Acute Brain Injury: Words Of Caution
March 17, 2020 | Amit Agrawal, Luis Rafael Moscote-Salazar, Ravish Keni

Functional and structural integrity of severely injured brain remains a challenge for clinicians and neuroscientists.1 New studies2 are further expanding our understanding on noninvasive methods to evaluate the structural integrity of brain functions.1,3 Apparently, it has been presumed that the patients have normal hearing; however, auditory response has been shown to be reduced after brain injury in many clinical studies.4,5 There is a need to identify the presence or absence of pre-existing hearing impairment to find out its impact on brain activation. It needs to be further clarified whether evoked potential can help us to confirm the integrity of hearing. It is also important to note that apparently global insult due to systemic factors (cardiac arrest) causes more damage than more focal insult (TBI > SAH). There is a further need to understand the severity of injury, e.g., imaging evidence of global versus focal injuries, dominant versus non-dominant side lesions. Studies have shown promising results as majority of the patients at follow-up though dependent were alive. How to interpret and apply these findings on individualized basis is the next challenge.


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