Tehran University of Medical Sciences Auditory and Vestibular Research 2423-480X 0 0 2025 09 21 1460 1460 Navid Nourizadeh Department of Otorhinolaryngology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran. Mojtaba Fallah 1- Department of Otorhinolaryngology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran. Hadi Behzad Echo Hearing and Balance Clinic, Mashhad, Iran. Setare Kafashan Echo Hearing and Balance Clinic, Mashhad, Iran. Hassan Mehrad-Majd Clinical Research Development Unit, Ghaem Hospital, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran. 2025 06 09 2025 08 07 Background and Aim: Patients with chronic otitis media (COM) who undergo mastoidectomy sometimes experience imbalance, dizziness, and vertigo after the surgery. This study aimed to investigate the effects of mastoidectomy on the balance of patients with COM using standard and advanced balance tests. Methods: The study was conducted in 2024 in Imam Reza and Ghaem hospitals affiliated with Mashhad University of Medical Sciences, Mashhad, Iran. Forty patients scheduled for mastoidectomy were enrolled over a 12-month period using a census method. Patients underwent balance tests before and after surgery. These tests included the Video Head Impulse Test (vHIT), Subjective Visual Vertical (SVV), and Posturography. Results: Statistical analysis of the performance parameter under linear or sinusoidal plate movement conditions showed no significant difference before and after the surgery (P > 0.05). Statistical analysis of the Gain in the six semicircular canals in the vHIT test also showed no significant difference before and after the surgery (P > 0.05). Similarly, statistical analysis of the deviation from the norm in the neutral position, -30° head tilt to the right, and -30° head tilt to the left showed no significant difference before and after the surgery (P > 0.05). Conclusion: The results of this study showed that mastoidectomy does not have a significant effect on balance tests, so performing it may not lead to severe balance disorders in patients with chronic otitis media who are candidates for mastoidectomy surgery. https://avr.tums.ac.ir/index.php/avr/article/view/1460