---

Background: Systemic and hemodynamic complications associated with stereotactic and Mayfield pin insertion pain and is one of the major problems in neuro-anesthesiology. The aim of this study was to decrease patients' hypertensive response to pain and stressful condition of the disease which may bring about problems during operation. Materials and Methods: In a randomized, double-blind clinical trial, thirty 16-65 year old ASA I and II patients at Al-Zahra Hospital of Isfahan were analyzed between September 2008 and November 2009. The level of pain according to VAS of pain was obtained from the patients in three stages: After pin insertion (stage 1), while returning from MRI (stage 2), and at the end of the procedure (stage 3) and recorded in the questionnaire. Data were analyzed through SPSS software. Results: The mean VAS of pin insertion pain for lidocaine in the three stages was 5.46, 5.00, and 2.46 and for bupivacaine was 5.76, 3.76 and 1.40, respectively (P<0.005). This indicated a significant difference between lidocaine and bupivacaine. Conclusion: As stereotactic operations take 3 to 3.5 hours on average, the use of bupivacaine instead of lidocaine is highly recommend during pin insertion.