Supine PositionSkullProne PositionHeadPostureSkull BasePatient PositioningHead and Neck NeoplasmsSkull NeoplasmsSkull Base NeoplasmsSkull FracturesHead MovementsTilt-Table TestFemur HeadHead-Down TiltHeart RateSupinationHypotension, OrthostaticSperm HeadGravitationNephrostomy, PercutaneousCraniocerebral TraumaBlood PressureHead Injuries, ClosedRespiratory MechanicsSkull Fracture, DepressedFemur Head NecrosisAutonomic Nervous SystemTomography, X-Ray ComputedMovementRespirationIndoraminValsalva ManeuverParietal BonePressureSyncopeDizzinessBaroreflexSyncope, VasovagalNeckHemodynamicsTime FactorsCardiac OutputExpiratory Reserve VolumeTidal VolumeReference ValuesLegSudden Infant DeathPulmonary Gas ExchangeMagnetic Resonance ImagingFluid ShiftsPalate, SoftTechnetium Tc 99m Aggregated AlbuminCranial SuturesEsophagusLung Volume MeasurementsEsophageal pH MonitoringRibsPulmonary CirculationPharynxMolecular Sequence DataOxygenRestOccipital BoneSleepCephalometryThoracic WallBlood Flow VelocityCraniosynostosesSleep ParalysisBedsBiomechanical PhenomenaFunctional Residual CapacityReproducibility of ResultsInhalationPelvisProspective StudiesImaging, Three-DimensionalDiaphragmLungAutonomic Nervous System DiseasesRegional Blood FlowSpineCarbon DioxideAirway ResistanceCentral Venous PressureVentilators, Negative-PressureTonguePlethysmographyAirway ObstructionHead Protective DevicesCarcinoma, Squamous CellLymphatic IrradiationElectrocardiographyPneumoperitoneum, ArtificialVeinsIntraocular PressureEsophageal Motility DisordersOropharynxVenous Pressure