Abstract: This study describes a patient with an intradural extramedullary (IDEM) tumor removed entirely using the unilateral biportal endoscopic technique (UBE), achieving satisfactory clinical outcomes. A 60-year-old woman had a diagnosis of meningioma with sensations and motor dysfunction in the lower extremities and perineum and gait disturbances for three years, which has worsened over the last month. Preoperative imaging data showed a sizeable IDEM tumor at the T10 level, significantly compressing the thoracic spinal cord to the right side, with 80% intraspinal encroachment. The IDEM tumor was removed entirely by UBE surgery. To the best of our knowledge, this study may be the first to report the application of UBE techniques for IDEM tumor treatment. In this case, UBE provides a magnified and clear surgical field, greater maneuverability, and a less invasive surgical procedure. The procedure objectives were pathological confirmation, spinal cord decompression, and complete tumor removal; all were met. The patient was satisfied with her dramatically improved clinical symptoms. UBE may be an alternative surgical treatment option for benign IDEM tumors presenting with symptomatic, especially the non-giant lateral and posterior tumors.

Keywords: unilateral biportal endoscopy, endoscopic spine surgery, intradural extramedullary, tumor, meningioma