RESUMO
The course of the facial nerve (FN) has been extensively investigated in patients with vestibular schwannomas (VSs). FN running dorsally to the tumor capsule accounts for less than 3% of the cases. Diffusion tensor imaging (DTI)-based fiber tracking helps to preoperatively identify the FN. During surgery, a higher risk of injury is associated with the dorsal location of the FN. The authors demonstrate the nuances and tricks to identify and preserve a dorsal displaced FN during resection of a large VS, T3b according to the Hannover classification, through the retrosigmoid-transmeatal approach. The video can be found here: https://stream.cadmore.media/r10.3171/2021.7.FOCVID2182.
RESUMO
BACKGROUND: According to our research, just few studies described 5-Aminolevulinic acid (5-ALA) use for spinal injuries resection. 5-ALA is known to be especially useful in certain spinal tumor entities such as meningiomas, ependymomas, hemangiopericytomas, and metastasis of central nervous system primary tumors. In contrast, 5-ALA has limited value in other histopathological tumoral entities, as neurinomas and carcinoma metastasis. METHOD: We describe a microsurgical resection of a spinal cord melanoma through fluorescence-guided technique using 5-ALA in a 36-year-old man. RESULTS: Strong 5-ALA tumor enhancement was evidenced, resulting in gross-total resection. CONCLUSION: To our knowledge, this is the first case of nonglial intramedullary metastasis with 5-ALA positive staining. We believe that this tool, 5-ALA, could aid in the resection, identification, and differentiation of medullary metastasis.
