If only a Distant Cerebral CT is Available, Referrals must be Triaged for Mild Traumatic Brain Injury or Concussion

We read with interest the article by Lavery et al. on a retrospective review of the incidence of patients with mild traumatic brain injury (TBI) or concussion occurring between 1/2021 and 12/2021 who met the Canadian CT Head Rule (CCHR) for cerebral computed tomography (CCT) in a remote hospital [1] .A total of 124 patients met the inclusion criteria, but only 62% of them met the CCHR for undergoing CCT [1] .Of these patients, only 35% were actually referred for imaging [1] .It was concluded that only a third of patients who met the CCHR criteria were actually referred for CCT, so efforts need to be made to bridge the disparities in the provision of CCT in rural and urban areas [1] .The study is noteworthy, but some points should be discussed.The first point is that the CCHR has the weakness of not taking into account the time course of symptoms after an TBI.If a patient has a persistent headache, fever, dizziness, disorientation or loss of consciousness in the next few hours after the TBI, a CCT should be performed, even if it is distant.Loss of consciousness, amnesia and observed disorientation immediately after the TBI should not be the only criteria.The second issue is that the term "mild TBI" was not defined for the study [1] .Referral of TBI patients to a distant CCT may strongly depend on the type and severity of the TBI.A TBI is usually defined as a violent blow or impact to the head or body.An object that penetrates the brain tissue, such as a bullet or a shattered piece of skull, can also cause a severe TBI.A TBI can also be caused by a sudden acceleration or deceleration of the head in a person whose body is immobilized, such as in an airplane or car.Mild TBI can only affect neurons temporarily.More severe TBI can lead to bruising, tissue tears, bleeding and other physical damage to the brain.These injuries can lead to^long-term complications or death.Severe and certain mild TBI always require referral to a CCT.How was a mild TBI actually defined?The third point is that the exact number of patients who have suffered a concussion is not known [1] .According to most national and international guidelines, immediate cerebral imaging is required for patients with concussion.However, if the nearest CT scanner is 100 kilometers away, patients with concussion must be triaged.Patients with persistent focal neurological deficits must be referred to CCT immediately, whereas patients without deficits and complete reorientation can wait.The same applies to patients who suffer a seizure after a concussion and those who develop elevated inflammatory parameters.Immediate cerebral imaging is also required in these patients.The fourth point is that the outcome of the two-thirds of patients with TBI who did not have a CCT was not reported.How many of them suffered severe long-term damage because they had not undergone cerebral imaging?For how many of them did the lack of CCT have no impact on long-term prognosis and outcome?The fifth point is that the chart review also covered part of the pandemic (12/2019 to 12/2021) [1] .Therefore, we should know in how many cases a transfer to the remote CCT was not performed due to SARS-CoV-2 positivity, although it was indicated.To summarize, this interesting study has limitations that put the results and their interpretation into perspective.Addressing these limitations could strengthen the conclusions and support the study's message.When only remote CCT is available, referrals need to be screened for mild TBI or concussion with persisting or new deficits or abnormalities after the TBI.