This book offers a comprehensive overview of thyroiditis, a group of diseases that often present with similar symptoms, frequently creating a diagnostic challenge in determining the exact etiology. Thyroiditis accounts for approximately 20% of all thyroid diseases and arises from various causes, most commonly autoimmune disorders. Clinical manifestations may include symptoms of hyperthyroidism or hypothyroidism, with subtle variations depending on the underlying cause. A detailed clinical history and a thorough physical examination are essential for accurate diagnosis. The volume covers anatomy, physiology, and diagnostic investigations of the thyroid gland, along with the etiology, pathophysiology, diagnosis, and treatment strategies for different forms of thyroiditis?both autoimmune (e.g., Hashimoto?s disease, de Quervain?s subacute thyroiditis, Riedel?s fibrosing thyroiditis) and non-autoimmune (e.g., acute suppurative thyroiditis, drug-induced thyroiditis, post-operative necrotizing thyroiditis, radiation thyroiditis). Additional chapters address updates in dietary management of Hashimoto?s thyroiditis, Hashimoto?s encephalopathy, ophthalmopathy, and associated anxiety and depression. A concluding chapter reviews the latest evidence on surgical management of thyroiditis variants, including indications, operative techniques, and post-operative complications. This book is an invaluable resource for head and neck surgeons, maxillofacial surgeons, otolaryngologists, endocrinologists, oncologists, and trainees involved in the care of patients with inflammatory thyroid lesions.