P04.06 The incidence and impact of post-operative stroke in surgery for LGG

Abstract

Abstract BACKGROUND: INTRODUCTION Postoperative neurological deficits may outweigh the benefit conferred by maximal resection of gliomas. Ischemic complications are a common cause of such deficits. In this study, we evaluated the incidence of ischemic events in patients undergoing surgery for low-grade gliomas (LGG) and the long-term neurological and cognitive implications of those events. METHODS Between 2013–2017, 168 patients underwent surgical resection or biopsy for LGG at our center. A full dataset, including pre- and postoperative magnetic resonance imaging (MRI) and long-term clinical evaluation findings, was available in 82 patients that underwent resection, and they comprised our study cohort. We retrospectively analyzed pre- and postoperative demographic, clinical, radiological, anesthetic, and intraoperative neurophysiology data to characterize associated ischemic complications. Overall and progression-free survival, as well as functional and neurocognitive outcomes were evaluated as well. RESULTS The immediate postoperative MRI showed evidence of an acute ischemic stroke adjacent to the tumor resection cavity in 19 patients (23%), 13 of whom developed new neurological deficits as a result of the ischemic event. Infarcts were more common in patients undergoing surgery for a recurrent tumor, especially those involving the Sylvian fissure (p<0.05). Surgery for insular gliomas had the strongest association with postoperative infarcts (multivariate analysis: odds ratio =12.4, 95% confidence interval 2.21–69.8). There was no difference in survival between patients with or without a postoperative infarct. The median Karnofsky Performance Status was lower for the infarct group compared to the non-infarct group at 3 months after surgery (p=0.016), with a gradual significant improvement for the former over one year of follow-up (p=0.04). Immediately after surgery, 27% of the patients without infarcts and 58% of those with infarcts experienced a new motor deficit (p=0.037), decreasing to 16% (p=0.028) and 37% (p=0.001), respectively, at one year. Neurocognitive analysis findings before and 3 months after surgery were unchanged, but there was a significant decrease in naming in patients who experienced an infarct (NeuroTrax computerized battery score of 100±9 and 83±19, p=0.04 respectively). Confusion during awake craniotomy was a strong predictor of the occurrence of an ischemic stroke. CONCLUSIONS Intraoperative strokes are more prevalent among patients who undergo recurrent surgeries, especially procedures in the insula. Although they do not affect survival, these strokes negatively affect the patients’ activity and performance status, especially during the first 3 postoperative months, with gradual functional improvement over one year.