Repeating the head CT in patients with head injury has almost become routine. This practice varies greatly and depends on the neurosurgeon’s preference in many centers. It occurs most commonly when there is blood inside the skull, any type of blood. But does this practice make sense? Sure, if you’ve got a small epidural it seems reasonable. But what about that wisp of subarachnoid blood?

Another paper being presented at the Congress of Neurologic Surgeons this fall describes a review of 445 cases at their hospital and a meta-analysis of 15 studies in the literature. The authors looked at the practice of repeat CT scanning with respect to the good old clinical exam. They stratified all patients who underwent an intervention after repeat CT into two groups, based on changing clinical exam or CT findings.

They found that a significant number of patients required some management change based on deteriorating neurologic exam, whereas very few required it based on the repeat CT. The authors concluded that it is not necessary to rescan a head trauma patient if their neurologic status is stable or improving. 

Bottom line: This is preliminary data, and it is only available in abstract form, so don’t change your practice yet. We need more information on how many patients were reviewed and how good the meta-analysis was. However, you should begin to question whether rescanning everyone is necessary or prudent. Not all head injuries are alike, and some of the trivial ones, like subarachnoid blood in a young adult probably don’t need a repeat scan. More to come when this is presented and/or published.

Reference: The Value of Scheduled Repeat Cranial Computed Tomography Following Mild Head Injury: Single Center Experience and Meta-Analysis. Paper 152, presented at the Congress of Neurologic Surgeons, October 2012.