Fig. 1

A, B High-intensity zone of L4/5 segment intervertebral disc annulus fibrosus can be seen in the preoperative lumbar MRI; C, D the working channel of spinal endoscopy during operation; E intraoperative images showed the “isolation zone” formed in the nerve root and ventral dura after endoscopic decompression; F, G one week after operation, the lumbar MRI was rechecked, and the signal of fibrillar ring tear disappeared; the range of ventral decompression of dura mater was sufficient; H, I the lumbar MRI was reexamined 10 months after operation, the tear of fibrous ring disappeared; the surgical scope of the "isolation zone" healed well