THE IMPACT OF THE FRONTAL ASLANT TRACT ON POST-OPERATIVE OUTCOMES IN GLIOMA SURGERY

Abstract AIMS The frontal aslant tract (FAT) has a role in speech and language functions and visual-motor activities. It is also not clear whether location of FAT relative to gliomas affects post-operative motor and language outcomes. Our hypothesis is FAT protects the cortico-spinal tract and other subcortical white matter tracts involved in speech. METHOD We conducted a retrospective cohort study. We used electronic patient records to search for all patients who had frontal tumours resected between Jan 2018 and August 2022. We included all adult patients (>18 years) with gliomas located in the SMA region and dorsal premotor cortex who had pre-op diffusion tensor imaging and underwent debulking / resection surgery. The patients were divided into 3 groups based on the location of the tumour relative to FAT. In group 1 patients had tumours located anterior to FAT, in group 2 patients had tumours infiltrating FAT and in group 3 patients had tumours located posterior to FAT. Our outcome measure was new post-operative language or motor deficit. RESULTS Our search yielded 197 patients, of these 43 fulfilled the inclusion criteria. Sixteen patients were included in group 1, 9 patients included in group 2 and 18 included in group 3. Pre-operative motor deficit was significantly more common in patients with tumours posterior to FAT (p=0.046). Post-operative motor deficit at hospital discharge was also more common on this group of patients (p=0.048). At 6 months follow up there was no significant difference post-operative motor and language deficits between the groups but there was a trend towards worse motor outcomes in patients with tumour located posterior to FAT. CONCLUSION There is a suggestion motor outcomes are worse in tumours located posterior to FAT. This can be considered when counselling patients for surgery with tumours related to FAT.