Epidural space硬膜外隙 Position: lies between spinal dura mater and periosteum of vertebral canal Contents: a quantity of loose connective tissue, fat, lymphatic vessels and vertebral venous plexus, the spinal nerves on each side pass through the epidural space which is applicable for block anesthesia Subdural space硬膜下隙Epidural space 硬膜外隙 ◼ Position: lies between spinal dura mater and periosteum of vertebral canal ◼ Contents: a quantity of loose connective tissue, fat, lymphatic vessels and vertebral venous plexus, the spinal nerves on each side pass through the epidural space which is applicable for block anesthesia Subdural space硬膜下隙