The study is carried out in a prospectively randomly controlled way. In the context of acknowledgement and understanding from parents, by comparing with traditional process(no anesthesia), lidocaine surface anesthesia is randomly selected. All children will be evaluated by the FLACC (The face, legs, activity, cry, consolability behavioral tool) scale to quantitatively assess degree of pain during lumbar puncture. Time and success rate of the lumber puncture will be recorded and analyzed. A questionnaire about bad memory during lumbar puncture for all parents and children will be investigated in order to establish an optimized lumbar puncture management process.