Combined use of 5-Aminolevulinic Acid and Low-field Intraoperative Magnetic Resonance Imaging in High-Grade Glioma surgery.

ABSTRACT Objective To assess the impact of 5-Aminolevulinic Acid(5-ALA) and Low-field Intraoperative Magnetic Resonance Imaging(iMRI) in the extent of resection(EoR) of high-grade gliomas(HGG). Results are compared with those obtained when using 5-ALA and iMRI separately. Methods We retrospectively included patients with a HGG eligible for gross total resection(GTR) from January 2013 to January 2018. Patients were included according to 5-ALA surgical guidance(5A-group), iMRI(iMRI-group) or both(5A-iMRI-group). Surgical variables were registered and, pre and post-surgical radiological and clinical variables were analysed. EoR≥90%, complications and new permanent neurological deficit were compared using the Chi2 and ANOVA tests. Other variables studied were: Mortality(M), average hospital stay(AHS), surgical time(ST) and Karnofsky Performance Status before and after surgery(KPS Pre/Post). Results 118 procedures were carried out(59.2% men). Mean age was 58 years. Sixty patients(50.8%) were operated using exclusively 5-ALA assistance(5A-group), 19(16.1%) using iMRI (iMRI-group) and 39(33%) combining both techniques(5A-IMRI-group). There were no statistically significant differences between three groups regarding EoR≥90% (73% 5A, 73.7% iMRI, 71.8% 5A-iMRI, p=0.94), complication rates(18.3% 5A, 5.3% iMRI, 7.7% 5A-iMRI, p=0.17), new or worsening of pre-existing neurological deficit at 1 month follow-up(13.3% 5A, 10.5% iMRI, 15.4% 5A-iMRI, p = 0.26), AHS in days(9.5 5A, 6.4 iMRI, 7.6 5A-iMRI, p = 0.18), KPS nor ST in minutes(212.4 5A, 187.9 iMRI, 201.4 5A-iMRI, p = 0.13). Conclusions In our experience, combined use of iMRI and 5-ALA does not improve the studied variables when compared to those technologies when used separately, even though a slight tendency of a superior effectiveness is observed when using iMRI individually.