Tuberculous spinal arachnoiditis (adhesions) is one of the serious complications of tuberculous meningitis, manifesting as paraplegia or quadriplegia, urinary and fecal retention, and sensory planes, which is difficult to treat. We applied cerebrospinal fluid replacement plus intrathecal oxygen injection method to treat tuberculous spinal arachnoiditis with satisfactory results, which are reported as follows. 1. Data and methods 1.1 General data Two male cases and two female cases. The ages ranged from 2O to 42 years, with an average of (38.8±10) years. 4 cases were clinically and cerebrospinal fluid examination were consistent with the diagnosis of tuberculous meningitis, 1 case was combined with pulmonary tuberculosis, and 1 case was combined with pleural effusion. Three cases developed paraplegia and one case of tetraplegia during anti-TB treatment, all with spinal sensory planes; one case had difficulty in urination, three cases had urinary retention, and all had difficulty in defecation. The duration of the disease ranged from 23 to 50 d, with a mean of (34.5±l1.4) d. The time from nodal brain to the appearance of spinal arachnoiditis ranged from 15 to 3O d, with a mean of (23.3±6.7) d. 1.2 Treatment All cases continued treatment with quadruple anti-tuberculosis drugs (isoniazid, rifampin, streptomycin and pyrazinamide), hormones, vitamins and appropriate amounts of mannitol, with the addition of this method. After successful conventional lumbar puncture, the patient was slowly released 3-5 mL of cerebrospinal fluid, and then replaced with saline 2O-40 mL in 4-5 times, each time so that the outflow of cerebrospinal fluid was 1-2 mL more than the injected saline, and the total amount of cerebrospinal fluid released after replacement was 10 mL. The replacement process should be slow, and the replacement time should not be less than 3O min in severe patients. Finally, filtered oxygen was extracted with a sterile empty needle and injected into the subarachnoid space. Oxygen was injected every 6-7 d. A total of 17 injections were made in 4 patients. The amount of oxygen injected was 2O-48mL, starting from a small amount according to the patient’s tolerance. 2. Results: 2 patients received 5 injections of oxygen and 1 patient received 4 injections of oxygen. 37-89 days of hospitalization were spent in these 3 cases. muscle strength recovered from L-II level before oxygen injection to IV+ level, and they were able to walk on their own and urination returned to normal. In one case, the muscle strength recovered to grade II after 3 times of oxygen injection, and the general pain was significantly reduced. 3, Discussion This group was combined with symptoms and signs of arachnoid adhesions on the basis of tuberculous meningitis, and the condition did not improve despite effective anti-tuberculosis treatment. Later, after the treatment of cerebrospinal fluid replacement with intrathecal oxygen injection, the condition improved significantly. 1~2 d after each oxygen injection, the patient felt stronger than before and the symptoms were reduced, indicating that this method of treatment was effective. Oxygen injection into the subarachnoid space can produce a certain pressure and play a peeling effect, which is conducive to the release of tissue adhesions, the dissipation and repair of tissue inflammation, and the improvement of the aerobic metabolic process of the spinal cord. This method easily allows anti-tuberculosis drugs to reach the lesion, and the pH of the cerebrospinal fluid is changed by the high concentration of oxidative environment may enhance the efficacy of anti-tuberculosis drugs. Intrathecal flumethasone injection can be anti-inflammatory, reduce exudation, prevent arachnoid adhesions, and also have anti-free radical and reduce cerebral edema effects. The cerebrospinal fluid pressure did not change much after the release of cerebrospinal fluid, so cerebrospinal fluid replacement was given before oxygen injection, which may replace harmful substances, proteins and pathogenic bacteria and help reduce the occurrence of adhesions. Intrathecal oxygen injection has been used to treat unexplained spinal arachnoiditis with good efficacy, and this group shows that it is equally effective in treating tuberculous arachnoiditis. We have experienced that the efficacy is related to the amount of oxygen injection, and the improvement of symptoms and signs is obvious with a large amount of oxygen injection. However, since patients have different tolerance to oxygen injection, the amount of oxygen injection should be decided according to the patient’s tolerance, starting with a small amount if necessary.