Frontal SinusParanasal SinusesParanasal Sinus DiseasesSinusitisEndoscopyRhinitisOtorhinolaryngologic Surgical ProceduresNasal PolypsMaxillary SinusEthmoid SinusMucoceleEthmoid SinusitisParanasal Sinus NeoplasmsFrontal SinusitisHeadacheEthmoid BoneSphenoid SinusCerebrospinal Fluid RhinorrheaMaxillary SinusitisOrbitEndoscopesChronic DiseaseCranial SinusesFrontal BoneTomography, X-Ray ComputedCavernous SinusTurbinatesSkull BasePneumocephalusNasal SeptumAkinetic MutismFrontal LobeHeadache DisordersSinus of ValsalvaOlfaction DisordersMaxillofacial AbnormalitiesCarotid SinusOsteomaTension-Type HeadacheCoronary SinusCraniotomyCluster HeadacheTreatment OutcomeOrbital DiseasesMagnetic Resonance ImagingSinus Thrombosis, IntracranialNasal SpraysProspective StudiesSuperior Sagittal SinusRetrospective StudiesSick Sinus SyndromeNose DiseasesTrephiningOsteoblastomaCholesteatomaQuality of LifeVascular HeadachesFollow-Up StudiesSkull FracturesTachycardia, SinusMigraine DisordersNasal LavageMaxillary Sinus NeoplasmsHeadache Disorders, SecondaryOtolaryngologyPilonidal SinusCranial Sutures