ORTHOPTIST LED VISUAL fiELD MONITORING DURING AWAKE CRANIOTOMY OF LOW GRADE GLIOMA: A UK TERTIARY CENTRE EXPERIENCE

Abstract AIMS To describe orthoptist led monitoring of visual function during awake craniotomy for low grade glioma and to retrospectively review visual field outcomes comparing to published results. METHOD Intraoperative visual field monitoring was performed by the same advanced orthoptist, performing fields to confrontation as well as monitoring for observed visual phenomena. Goldman visual fields were performed pre-operatively and approx. 6 weeks post operatively. Results compared to published outcomes. RESULTS 26 awake procedures were attended with 2 being repeat surgeries therefore 28 surgical episodes. Testing was abandoned for 6 (inability to wake sufficiently, inability to cope with the awake procedure or change in diagnosis from low to high grade). Results were retrospectively reviewed over a five year period from 2019 to 2024. Post operative visual fields were found to be unaltered or only mild superior dipping (not precluding driving) in 18 patients, loss of field to a quadrantiopia negating driving requirements in 2, 2 patients with quadrantiopia pre and post op unchanged. CONCLUSION Visual field assessment during awake craniotomy can give surgeons additional confidence to continue the resection. Utilisation of an Orthoptist with minimal equipment as well as no alteration to the surgical positioning has demonstrated comparable visual outcomes to those published. The authors would recommend that other centres consider utilization of specialised allied health professionals to assess and monitor eloquent function during awake procedures; such as orthoptists for visual function.