OBJECTIVE The aim of this study was to assess the precision and feasibility of 3D-printed marker–based augmented reality (AR) neurosurgical navigation and its use intraoperatively compared with optical tracking neuronavigation systems (OTNSs). METHODS Three-dimensional–printed markers for CT and MRI and intraoperative use were applied with mobile devices using an AR light detection and ranging (LIDAR) camera. The 3D segmentations of intracranial tumors were created with CT and MR images, and preoperative registration of the marker and pathology was performed. A patient-specific, surgeon-facilitated mobile application was developed, and a mobile device camera was used for neuronavigation with high accuracy, ease, and cost-effectiveness. After accuracy values were preliminarily assessed, this technique was used intraoperatively in 8 patients. RESULTS The mobile device LIDAR camera was found to successfully overlay images of virtual tumor segmentations according to the position of a 3D-printed marker. The targeting error that was measured ranged from 0.5 to 3.5 mm (mean 1.70 ± 1.02 mm, median 1.58 mm). The mean preoperative preparation time was 35.7 ± 5.56 minutes, which is longer than that for routine OTNSs, but the amount of time required for preoperative registration and the placement of the intraoperative marker was very brief compared with other neurosurgical navigation systems (mean 1.02 ± 0.3 minutes). CONCLUSIONS The 3D-printed marker–based AR neuronavigation system was a clinically feasible, highly precise, low-cost, and easy-to-use navigation technique. Three-dimensional segmentation of intracranial tumors was targeted on the brain and was clearly visualized from the skin incision to the end of surgery.

Glioblastoma multiforme (GBM) is the most common form of primary brain tumors. Although mutations in isocitrate dehydrogenase‐1 (IDH1) have been identified in a number of cancers, their role in tumor development has not been fully elucidated. In this preliminary study we aimed to investigate the association between IDH1 mutations, tumor tissue HIF‐1 alpha and serum VEGF levels in patients with primary GBM.32 patients (mean age, years: 58 ± 14.0) diagnosed with primary glioblastoma multiforme were screened for IDH1 mutations (R132H, R132S, R132C and R132L) by direct sequencing. Serum VEGF and tumor tissue HIF1‐alpha levels were measured by ELISA. Associations between categoric variables were determined using chi‐square tests. Differences between two groups were compared with t test for continuous variables. Two patients were heterozygous for R132H mutation (6%). Tumor HIF1‐alpha and serum VEGF levels were found to be significantly increased in IDH1‐mutated tumor tissues. Wild Type IDH1 (n=30) Mutant IDH1 (n=2) p Serum VEGF (ng/ml) 0.189 ± 0.08 0.309 ± 0.016 0.0454 Tumor HIF1‐α (ng/ml) 0.710 ± 0.835 5.058 ± 3.75 < 0.0001 Our preliminary results suggest that mutated IDH1 may contributes to carcinogenesis via induction of HIF‐1 alpha pathway in primary GBM.