BACKGROUND: Understanding the microsurgical neuroanatomy of the brain is challenging yet crucial for safe and effective surgery. Training on human cadavers provides an opportunity to practice approaches and learn about the brain's complex organization from a surgical view. Innovations in visual technology, such as virtual reality (VR) and augmented reality (AR), have immensely added a new dimension to neuroanatomy education. In this regard, a 3-dimensional (3D) model and AR/VR application may facilitate the understanding of the microsurgical neuroanatomy of the brain and improve spatial recognition during neurosurgical procedures by generating a better comprehension of interrelated neuroanatomic structures. OBJECTIVE: To investigate the results of 3D volumetric modeling and AR/VR applications in showing the brain's complex organization during fiber dissection. METHODS: Fiber dissection was applied to the specimen, and the 3D model was created with a new photogrammetry method. After photogrammetry, the 3D model was edited using 3D editing programs and viewed in AR. The 3D model was also viewed in VR using a head-mounted display device. RESULTS: The 3D model was viewed in internet-based sites and AR/VR platforms with high resolution. The fibers could be panned, rotated, and moved freely on different planes and viewed from different angles on AR and VR platforms. CONCLUSION: This study demonstrated that fiber dissections can be transformed and viewed digitally on AR/VR platforms. These models can be considered a powerful teaching tool for improving the surgical spatial recognition of interrelated neuroanatomic structures. Neurosurgeons worldwide can easily avail of these models on digital platforms.

This retrospective analysis of patients aims to show the blood levels of preoperative inflammatory markers in patients with glioblastoma and brain metastasis and to provide the diagnostic accuracy of the neutrophil–lymphocyte (NLR), lymphocyte–monocyte (LMR), and platelet–lymphocyte (PLR) ratios between the 2 groups of patients. The retrospective reviews of the neutrophil, lymphocyte, monocyte, and platelet counts were analyzed in 80 patients with newly diagnosed glioblastoma and 70 patients with brain metastasis. The NLR, LMR, and PLR were calculated in each group. The differences in all the parameters were compared between the 2 groups. Although the neutrophil, monocyte, and platelet counts were higher and the lymphocyte count was lower in patients with metastasis, the difference was not significant. A significantly higher PLR (P = .004) and a lower LMR (P = .01) were found in patients with brain metastasis. Although both PLR and LMR had diagnostic accuracy in differentiating glioblastoma from brain metastasis, LMR showed the highest diagnostic accuracy. NLR showed no diagnostic accuracy. Systemic inflammation is more severe in glioblastoma than in brain metastasis, and LMR is more sensitive and/or specific than PLR in differentiating glioblastoma from brain metastasis. Therefore, LMR (less likely PLR) can be used as an index for differentiating between glioblastoma and brain metastasis before surgery.

To describe the rare finding of a double massa intermedia (MI). Typically, the MI (interthalamic adhesion) is a single bridge of gray matter connecting the medial surfaces of the thalami. Twelve formalin- and alcohol-fixed human third ventricles were examined from superior to inferior by fiber dissection technique under ×6 to ×40 magnifications and with the endoscope. In all hemispheres, the anterior and posterior commissure were defined. The MI, which bridges the medial surfaces of the thalami, was defined in all hemispheres. In one hemisphere, there was a second bridge between the thalami, located posteroinferior to the common MI. Endoscopic view confirmed that there was a second MI in this specimen. The MI usually traverses the third ventricle posterior to the foramen of Monro and connects the paired thalami. The MI is an important landmark during endoscopic and microscopic surgeries of the third ventricle. Although a double MI is very rare, surgeons should be aware of the possibility in their surgical planning. The surgeon should be aware of the possibility of a double MI to avoid confusion during third ventricle surgery.