Facts HNO is the answer to the challenges of modern medicine, characterized by an ever-increasing accumulation of knowledge, time constraints in clinical practice, and the highest professional demands. The concisely formulated, comprehensive content and systematically structured layout provide insight into otorhinolaryngology and aim to help gain and maintain an overview. Symptoms, differential diagnoses, and treatment options for individual medical conditions are presented clearly and practically. A summary of anatomy, physiology, and the most important key symptoms precedes each chapter, facilitating (re)entry into the respective topic and briefly clarifying the understanding of the close topographical relationships of the anatomical structures in otorhinolaryngology. The guidelines of the German.