Suzanne E. Kosteniuk

Functional Magnetic Resonance Imaging for Preoperative Planning in Brain Tumour Surgery.

BACKGROUND Functional magnetic resonance imaging (fMRI) is being increasingly used for the preoperative evaluation of patients with brain tumours. METHODS The study is a retrospective chart review investigating the use of clinical fMRI from 2002 through 2013 in the preoperative evaluation of brain tumour patients. Baseline demographic and clinical data were collected. The specific fMRI protocols used for each patient were recorded. RESULTS Sixty patients were identified over the 12-year period. The tumour types most commonly investigated were high-grade glioma (World Health Organization grade III or IV), low-grade glioma (World Health Organization grade II), and meningioma. Most common presenting symptoms were seizures (69.6%), language deficits (23.2%), and headache (19.6%). There was a predominance of left hemispheric lesions investigated with fMRI (76.8% vs 23.2% for right). The most commonly involved lobes were frontal (64.3%), temporal (33.9%), parietal (21.4%), and insular (7.1%). The most common fMRI paradigms were language (83.9%), motor (75.0%), sensory (16.1%), and memory (10.7%). The majority of patients ultimately underwent a craniotomy (75.0%), whereas smaller groups underwent stereotactic biopsy (8.9%) and nonsurgical management (16.1%). Time from request for fMRI to actual fMRI acquisition was 3.1±2.3 weeks. Time from fMRI acquisition to intervention was 4.9±5.5 weeks. CONCLUSIONS We have characterized patient demographics in a retrospective single-surgeon cohort undergoing preoperative clinical fMRI at a Canadian centre. Our experience suggests an acceptable wait time from scan request to scan completion/analysis and from scan to intervention.

Impact of Functional Magnetic Resonance Imaging on Clinical Outcomes in a Propensity-Matched Low Grade Glioma Cohort

BACKGROUND This study aims to evaluate the impact of preoperative functional magnetic resonance imaging (fMRI) on clinical outcomes in patients with low grade glioma (LGG). METHODS In a retrospective propensity-matched cohort study, we compared patients with LGG based on whether they underwent fMRI as part of preoperative assessment. Twelve patients with LGG who underwent preoperative fMRI were selected, and a contemporaneous group of 12 control patients with LGG who did not undergo fMRI were matched to the fMRI group based on age, sex, and 1p/19q status. RESULTS fMRI group subjects tended to have more aggressive surgeries (67% resection, 33% biopsy) than the control group (33% resection, 67% biopsy). There were no significant differences in outcomes between the 2 groups. Time between clinical assessment and surgery tended to be longer in the fMRI group (6.3 ± 4.2 weeks) than in the control group (2.7 ± 2.2 weeks). Extent of resection was similar between the 2 cohorts. fMRI group subjects had lower preoperative functional status and tended to have a greater postoperative functional status improvement than control group subjects. Mean survival was not significantly different (fMRI group 5-year survival: 88.9%, control group 5-year survival: 61.1%). CONCLUSIONS We evaluated the impact of preoperative fMRI in patients with LGG in this propensity-matched cohort study. This study has not demonstrated any significant difference in outcomes between the fMRI and control groups; however, there were nonsignificant trends for patients who underwent fMRI to undergo more aggressive surgical interventions and have a greater postoperative functional status improvement.