in our study, we analyzed the imaging research and application of unilateral biportal spinal endoscopy (uBe) guided by CT three-dimensional (3D) reconstruction technology for the treatment of superior lumbar disc herniation (ULDH) through the ligamentum flavum interlaminar approach. We selected 65 patients with L1-4 LDH who underwent CT 3D reconstruction technology-guided unilateral bitportal spinal endoscopic surgery through the ligamentum flavum interlaminar approach in our department from December 2019 to December 2022. The relevant parameters of the L1-4 segments were measured on lumbar CT images. The intersection points of the lateral spinous process of each segment and the inferior border of the vertebral lamina were determined (Q-points). The vertical distances from the Q-point of each segment to the inferior border of the contralateral pedicle of the same segment, the superior border of the contralateral pedicle of the inferior vertebral body, the inferior endplate of the same segment, and the superior endplate of the inferior vertebral body were recorded as a1, a2, a3, and a4, respectively. all patients underwent preoperative CT examination in the prone position, with the inferior abdomen slightly padded and a similar position to the surgical position.