Indications of 5-Aminolevulinic Acid and Intraoperative MRI in Glioma Surgery: First Cases in Latin America in a Single Reference Center

Introduction The improvement on the extent of resection (EOR) of gliomas with the combination of 5-aminolevulinic acid (5-ALA) and intraoperative magnetic resonance imaging (iMRI) has been demonstrated in previous studies. We present our results with the combined use of 5-ALA and (iMRI) in the surgery of glial lesions. Methods A total of 64 cases of patients with intracranial gliomas who underwent image-guided surgery using 5-ALA with and without (iMRI) were reviewed. All patients underwent an early postoperative MRI to evaluate the EOR. Other intra-operative techniques (awake surgery, electrophysiological stimulation and monitoring) were also performed according to the location of the tumor. Results A total of 18 tumors did not show intraoperative 5-ALA fluorescence (according to the World Health Organization [WHO] classification of tumors, 2 WHO-grade I, 14 WHO-grade II, 1 WHO-grade III and 1 WHO-grade IV), and 46 tumors showed intraoperative 5-ALA fluorescence (3 WHO-grade II, 3 WHO-grade III, 40 WHO-grade IV). In 28 of the 46 5-ALA positive cases, a safe 5-ALA free resection was achieved. In the 5-ALA negative cases, the (iMRI) findings guided the EOR, and complete resection was achieved in 11 cases. Complete resection was opted out in gliomas infiltrating eloquent areas. Conclusions The combined use of 5-ALA and IMRI showed improved results in glioma surgery, offering the safest maximal EOR. In the 5-ALA positive cases (mostly high-grade), fluorescence was a more useful tool. In the 5- ALA negative cases (mostly low-grade), the (iMRI) was decisive to guide the EOR of the tumor.