Physicians examining traumatic brain injuries may want to rethink the classification systems they use for CT scans.

A study published in PLOS Medicine supports the adoption of new classification systems, such as the Stockholm CT score and Helsinki CT score, to replace older ones, such as the Rotterdam CT score and Marshall CT system.

The findings, deciphered by researchers from Karolinska Institutet and Karolinska University Hospital in Sweden and Helsingfors University Hospital in Finland, assert that the Stockholm CT score and the Helsinki CT score can better predict the progress of a patient over 6-12 months following his or her scan, compared to the Rotterdam CT and Marshall CT systems.

They also found that traumatic subarachnoid hemorrhage was the best aspect for predicting the outcome of a patient’s prognosis, most likely due to a lack of available treatments.

“The best way to introduce these scores is to do proper validations with external patient materials, comparing all CT scores/classifications, like we did in the current article (however, we do stress that further validation using TBI patients from other centers is necessary),” Dr. Eric Thelin, a researcher in the Department of Clinical Neuroscience from Karolinska Institutet and one of the authors of the study, told HCB News. “Moreover, clinicians treating these patients need to practice the CT assessment, but this is rather straightforward, and in the current article the intra-observer variability was low, suggesting both are quite easy to learn if you are used to assessing CT scans.”

The purpose of the study was to substantiate the efficiency of the new CT classification systems, which have not been extensively assessed. Data from the admission CT scans of 1,115 TBI patients who required neuro-intensive care were assessed under all four systems. 750 at Karolinska University Hospital were examined between 2005 and 2014 and 395 from Helsinki University Hospital were examined between 2013 and 2014. Age, pupil responsiveness, admission Glasgow Coma Scale, glucose level and hemoglobin level were also incorporated into the study.

The Stockholm CT score ranked the highest for overall prognostic performance with a Nagelkerke's pseudo-R range of 0.24-0.28. Helsinki CT score was second with a 0.18-0.22 score, followed by Rotterdam with a score of 0.13-0.15. Marshall had the lowest at 0.03-0.05. Stockholm CT score also contributed the most independent prognostic value in contrast to other clinical predictors of outcome in TBI patients at six percent. Helsinki’s was four percent.

The study found that 478 patients, about 43 percent, had an unfavorable outcome, according to the Glasgow Outcome Scale.

Thelin says that though the Stockholm system excelled, he believes that both the Stockholm and Helsinki CT scores will become standard tools in addressing traumatic brain injury since the Stockholm score is a little complex to assess.

“As compared to Rotterdam and Marshall CT score/classification, the Stockholm and Helsinki score include so much more information present on the CT scan that I definitely believe that they will be used to properly assess injury severity in the future, as the need to properly stratify cohorts in clinical trials will increase, as well as the need for proper initial assessment in order to guide resources to the patients with the greatest need,” he said.

The study cautions, though, that further validation of these systems at other centers is required to assess their efficiency.