UltrasonographyUltrasonography, Doppler, ColorUltrasonography, DopplerUltrasonography, PrenatalEndosonographyUltrasonography, Doppler, DuplexUltrasonography, Doppler, PulsedUltrasonography, MammarySensitivity and SpecificityUltrasonography, InterventionalUltrasonography, Doppler, TranscranialProspective StudiesTomography, X-Ray ComputedPregnancySulfur HexafluorideReproducibility of ResultsContrast MediaPredictive Value of TestsRetrospective StudiesUrographyFetal DiseasesBlood Flow VelocityImaging, Three-DimensionalScrotumCystsPreoperative CareDiagnostic Tests, RoutineTreatment OutcomeMagnetic Resonance ImagingPalpationAbdomenCarotid Artery DiseasesFollow-Up StudiesInfant, NewbornGestational AgeObserver VariationThyroid NoduleCarotid ArteriesEchoencephalographyGallbladderVaginaToe JointOvarian CystsLiver NeoplasmsFalse Positive ReactionsImage EnhancementTime FactorsMetacarpophalangeal JointRisk FactorsAbdominal InjuriesHydronephrosisDiagnostic ImagingSplenic DiseasesPrenatal DiagnosisTesticular DiseasesAuscultationPhysical ExaminationAngiographyRectumGallbladder DiseasesBiopsy, NeedleBiliary Tract DiseasesFalse Negative ReactionsPregnancy Trimester, SecondIntraoperative CareTransducersBiopsy, Fine-NeedleCarotid Artery, CommonEvaluation Studies as TopicOvarian FollicleCholangiopancreatography, Endoscopic RetrogradePolypsTunica MediaGallbladder NeoplasmsPortal VeinTendinopathyCholecystographyCarotid StenosisTesticular HydroceleUrinary TractPelvisMass ScreeningUterusCholelithiasisPulsatile FlowHysteroscopyCholangiopancreatography, Magnetic ResonanceRenal ColicWounds, NonpenetratingVenous ThrombosisPregnancy Trimester, FirstReference ValuesLaparoscopySynovitisPancreatic NeoplasmsDiagnostic ErrorsLaparotomyNeckAbdominal PainSeverity of Illness Index