Contralateral Transfalcine Approach for Recurrent Glioblastoma: A Technical Note on Multimodal Planning, Fluorescence-Guided Resection, and Reirradiation Strategy.

Abstract

Resection of recurrent glioblastoma (GBM) in eloquent brain regions is technically demanding due to altered anatomy, gliosis, and increased risk of neurological morbidity. Strategic use of alternative surgical corridors and multimodal guidance can facilitate safe and maximal resection. We describe the technical nuances of a contralateral transfalcine approach in a 61-year-old patient with a recurrent left fronto-mesial GBM previously treated via ipsilateral transcortical resection and Stupp protocol. To avoid re-entering scarred tissue and to preserve motor function, a right-sided interhemispheric transfalcine route was planned. Preoperative planning included navigated transcranial magnetic stimulation, positron emission tomography-magnetic resonance imaging fusion, magnetic resonance spectroscopy, and diffusion tensor imaging tractography. Intraoperative neuronavigation, continuous neurophysiological monitoring, and 5-aminolevulinic acid fluorescence guided the resection. Gross total resection was achieved via a transfalcine access through a right fronto-parietal craniotomy. Postoperative magnetic resonance imaging confirmed complete tumor removal. The histology revealed an isocitrate dehydrogenase-wildtype, unmethylated GBM. The patient remained neurologically intact, and a distant satellite lesion was treated with stereotactic reirradiation. No recurrence was noted at 1-year follow-up. This technical note illustrates that a contralateral transfalcine approach, supported by advanced multimodal planning, can optimize surgical outcomes in recurrent GBM near eloquent areas. It minimizes cortical transgression, facilitates en bloc resection, and integrates well into multidisciplinary treatment strategies.