New blood biomarkers may help quantify brain impact of neurosurgery

Brain damage in patients operated on for brain tumors can be assessed by measuring biomarkers in the blood before and after the operation. A new study by researchers at the University of Gothenburg shows that the increase in markers correlates well with the impairment caused by insufficient blood flow.

Today, examination with a magnetic camera (magnetic resonance imaging, MRI) is used after brain surgery to determine if the surgery has damaged the patient’s brain. MRI can identify bleeding (hemorrhages) and areas of the brain damaged by insufficient blood flow (ischemia).

MRI scans cannot always provide sufficiently detailed information about the degree of cell damage. In the long term, new biomarkers could fill this knowledge gap and offer more accurate and objective assessments of impairments due to brain tumor surgery. »

Isak Michaëlsson, doctoral student at the University of Gothenburg and resident in neurosurgery at the Sahlgrenska University Hospital

Insufficient blood flow and neurological deficit

Biomarkers that have now been studied in brain tumor surgery patients are well studied in the field of neurological diseases, particularly Alzheimer’s disease and other dementias and in patients with traumatic brain injury. The markers examined are known as neurofilament light (NfL), glial fibrillary acidic protein (GFAP), and tau protein. NfL is a marker for nerve cell fiber damage, GFAP for brain support cell damage, and tau for nerve cell damage.

This study is published in the scientific journal Neurosurgery. The study includes 34 adult patients with glioma, one of the most common types of brain tumours. The concentration of biomarkers was first measured the day before the intervention, then one, three, five and ten days after the intervention.

The study shows that the levels of markers in the blood correlate both with the extent of damage caused by the lack of oxygen that occurred during surgery and with the severity of the neurological deficit suffered by the patients.

Best possible treatment

The measurement of biomarkers in blood samples may become a new way to assess injuries caused by neurosurgery, thus allowing the comparison of surgical methods. Isak Michaëlsson again:

“It is also conceivable that elevated levels of these markers could be signs of damage that can lead to brain fatigue or other cognitive problems in patients in the somewhat longer term. If so, the markers could be used to identify patients at an early stage so that they get the right kind of rehabilitation”.