en Gamma Knife Radiosurgery Research <p style="text-align: justify;">Background & Aim: The most common primary brain tumors of the central nervous system are gliomas. Among a number of different biomolecular events, a strong relation between oxidative stress pathways and the development of this cancer has been proved. Oxidative stress (OS) is the consequence of an imbalance between pro-oxidants and antioxidants towards pro-oxidants. The pro-oxidants cause lipid peroxidation of cell membranes, protein, DNA oxidation and changes in brain cell growth. In this study, the pro-oxidant&ndash;antioxidant balance (PAB) was determined in patients with gliomas. Methods & Materials/Patients: Sera of 49 patients with high grade glioma (grade IV WHO) which is called glioblastoma multiform (GBM) and 49 healthy subjects were collected and PAB test was measured. Results: A significant increase of PAB value was observed in patients with GBM (158.10&plusmn;85.71 HK unit) in comparison to control group (74.54&plusmn;33.54 HK). Conclusion: The PAB assay showed the oxidative stress in glioblastoma. In further research, this easy elucidation of oxidative stress in these patients can be applied to evaluate the effectiveness of antioxidant therapies in patients with GBM.Keywords: Prooxidant-antioxidant; Balance; High</p> Prooxidant-antioxidant, Balance, High Grade Gliomas 27 30 http://irjns.org/browse.php?a_code=A-10-100-22&slc_lang=en&sid=1 Elnaz Farajirad الناز فرجی راد 10031947532846002992 10031947532846002992 No Head of Ghaem Health Center, Mashhad University of Medical Sciences, Mashhad, Iran. Kazem Ghaemi کاظم قائمی 10031947532846002993 10031947532846002993 No Associate Professor of Neurosurgery, Head of Neurosurgery Department, Faculty of Medicine, Birjand University of Medical Sciences, Birjand, Iran. Mehdi Khajavi مهدی خجوی 10031947532846002994 10031947532846002994 No Resident of Neurosurgery, Neurosurgery Department, Ghaem Hospital, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran. Daryoush Hamidi Alamdari داریوش حمیدی علمداری 10031947532846002995 10031947532846002995 No Stem Cell and Regenerative Medicine Research Group, Biochemistry & Nutrition Research Center, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran. Mohammad Hassan Arjmand محمد حسن ارجمند 10031947532846002996 10031947532846002996 No Master of Biochemistry, Surgery Department, Ghaem Hospital, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran. Mohammad Farajirad محمد فرجی راد 10031947532846002997 10031947532846002997 Yes Professor of Neurosurgery, Head of Neurosurgery Department, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.