The disease of the spinal column is number 2 of common diseases world-wide and leads to high business- and commerce-related losses as well as to high expenses for the health care systems. An effective treatment of this disease is given by the microinvasive. CT controlled periradicular therapy (micro PRT). Under visibility, the tip of a canula is led directly and high precisely in close neighbourhood to the prolaps, then locally NaCl and cristaline cortisone (40 mg Volon A) is instillated. The periradicular distribution and the distribution into the epidural space is documented via contrast medium. A retrospective study with 220 patients and a prospective randomized double blind study with 40 patients (10 mg vs. 40 mg Volon A) were carried out. The average age of the retrospective collective was 53.1 +/- 12.4 years, average treatment period 18.4 weeks, and the mean follow-up 17 months. The mean value of successful treatment of lumbal spine was at 60% (spine 88.5%) with protrusion, with prolaps at 75% (spine 94%), with sequester at 94%, and with stenoses at 69% (spine 60%). With 78.8% of the patients, the percentual result was constantly good at the time of questionnaire as to the end of the treatment. 7.7% still took analgesics, 5.9% were post-operated. 1.8% of the patients made a pension application. The average age of patients within the prospective randomized double-blind-study was 47.2 +/- 11.9 years. At 27.5% of the patients, the start of pain was about more than 5 years ago and goes back to about 23 years (72.5% had pain more than 1 year). The mean value of visits was 4 physicians per patient, and 5 months of follow-up. There is a high significant improvement in results within the group with 40 mg Volon A (p = 0.0351479). The entire improvement, subjectively estimated (visual analogical scale) within this group was at 90%. After end of therapy, 83.3% (n = 30) had stopped the taking of analgesics and the neurologic deficit decreased significantly. Furthermore, significant reduction of prolapses could be observed at 60% of the patients in both study groups (n = 156). The CT scopic micro PRT with 40 mg Volon A leads to a significant improvement of pain and neurologic symptoms caused by chronical disk herniation.