LaryngoscopyFiber Optic TechnologyOptical FibersLaryngoscopesIntubation, IntratrachealLarynxAirway ManagementEquipment DesignGlottisVideo RecordingLaryngeal DiseasesOptic NerveLaryngitisLaryngeal MasksVocal CordsAnesthesia, GeneralStructure CollapseManikinsRefractometryOptics and PhotonicsEquipment Failure AnalysisAnesthesiologyHeadLaryngeal NeoplasmsOptic DiskTransducersOptic NeuritisNerve FibersVocal Cord ParalysisOptic ChiasmBiosensing TechniquesOptic AtrophySpectrum AnalysisHoarsenessOptic Nerve InjuriesProspective StudiesSensitivity and SpecificityEpiglottisReproducibility of ResultsRetrognathiaDietary FiberMuscle Fibers, SkeletalLightDisposable EquipmentLingual Nerve InjuriesTooth InjuriesOptic Lobe, NonmammalianOptic Neuropathy, Ischemic