1. Introduction -- Section 1: Basic Science of Free Radical Biology in ENT -- 2. Free radicals and oxidative stress: Basic concepts and misconceptions -- 3. A Question of Balance:  Free Radicals and Cochlear Homeostasis -- 4. Antioxidants and their effect on stress-induced pathology in the inner ear -- Section 2: Epidemiology of Hearing Loss -- 5. Role of free radicals in hearing loss due to heavy metals -- 6. The role of nutrition in healthy hearing: human evidence -- Section 3: Oxidative Stress and Noise-Induced Hearing Loss -- 7. Basic mechanisms underlying noise-induced hearing loss -- 8. Oxidative stress in noise-induced hearing loss -- 9. Strategies for evaluating antioxidant efficacy in clinical trials assessing prevention of noise-induced hearing loss -- Section 4: Oxidative Stress and Drug-Induced Hearing Loss -- 10. Aminoglycoside-induced oxidative stress: pathways and protection -- 11. Hearing loss after cis-platin: oxidative stress pathways and potential for protection -- 12. Assessment of interventions to prevent drug-induced hearing loss (DIHL) -- Section 5: Oxidative Stress and Age-Related Hearing Loss -- 13. Age-related hearing loss: biochemical pathways and molecular targets -- 14. Genetics and age-related hearing loss -- 15. Mechanisms of age-related hearing loss -- 16. Interventions to prevent age-related hearing loss -- Section 6. Hereditary Hearing Loss -- 17. Genes and hearing loss: relationship to oxidative stress and free radical formation -- 18. Strategies for the treatment of hereditary hearing loss -- Section 7: Cochlear Implants, Radiation, Trauma and Other Stress Factors -- 19. Loss of Residual Hearing Initiated by Cochlear Implantation: Role of Inflammation-Initiated Cell -- 20. Role of oxidative stress in sudden hearing loss and Meniere's disease -- Section 8: Head and Neck -- 21. Role of free radicals in head and neck pathology -- 22. Free radicals and sleep apnea -- 23. Free radicals in nasal and paranasal disease -- 24. Conclusion.