This issue of Otolaryngologic Clinics, guest edited by Drs. Abtin Tabaee and Edward D. McCoul, is devoted to Refractory Chronic Rhinosinusitis. Articles in this issue include: Classification of Chronic Rhinosinusitis: Working Towards Personalized Diagnosis; Bacterial Pathogens and the Microbiome; Biofilm and Osteitis; Refractory Chronic Sinusitis with Polyposis; Aspirin-Exacerbated Respiratory Disease; Systemic and Odontogenic Etiologies in Chronic Rhinosinusitis; Genetic and Immune Dysregulation in Chronic Rhinosinusitis; Office Procedures in Refractory Chronic Rhinosinusitis; Topical Therapies and Stents; Revision Functional Endoscopic Sinus Surgery; Extended Endoscopic and Open Sinus Surgery for Refractory Chronic Rhinosinusitis; and An Algorithm for Comprehensive Evaluation and Management of Refractory Chronic Rhinosinusitis.

This issue of Otolaryngologic Clinics, guest edited by Drs. Abtin Tabaee and Edward D. McCoul, is devoted to Refractory Chronic Rhinosinusitis. Articles in this issue include: Classification of Chronic Rhinosinusitis: Working Towards Personalized Diagnosis; Bacterial Pathogens and the Microbiome; Biofilm and Osteitis; Refractory Chronic Sinusitis with Polyposis; Aspirin-Exacerbated Respiratory Disease; Systemic and Odontogenic Etiologies in Chronic Rhinosinusitis; Genetic and Immune Dysregulation in Chronic Rhinosinusitis; Office Procedures in Refractory Chronic Rhinosinusitis; Topical Therapies and Stents; Revision Functional Endoscopic Sinus Surgery; Extended Endoscopic and Open Sinus Surgery for Refractory Chronic Rhinosinusitis; and An Algorithm for Comprehensive Evaluation and Management of Refractory Chronic Rhinosinusitis.