Ultrasonography, DopplerUltrasonography, Doppler, ColorUltrasonography, Doppler, DuplexUltrasonographyUltrasonography, Doppler, PulsedUltrasonography, Doppler, TranscranialBlood Flow VelocityUltrasonography, PrenatalDoppler EffectSensitivity and SpecificityProspective StudiesPulsatile FlowRegional Blood FlowUltrasonography, InterventionalEchocardiography, Doppler, PulsedVenous InsufficiencyCarotid StenosisVaricose VeinsEchocardiography, Doppler, ColorPredictive Value of TestsReproducibility of ResultsPregnancyUmbilical ArteriesArterial Occlusive DiseasesUltrasonicsCerebrovascular CirculationLegAngiographyEchoencephalographyVascular PatencyVeinsCarotid Artery, InternalFemoral VeinContrast MediaTomography, X-Ray ComputedConstriction, PathologicVenous ThrombosisSaphenous VeinFetal DiseasesEndosonographyVascular ResistancePlacental CirculationTreatment OutcomeScrotumRetrospective StudiesCarotid Artery DiseasesPortal VeinFemoral ArteryFollow-Up StudiesTime FactorsMagnetic Resonance AngiographyMiddle Cerebral ArteryCerebral ArteriesAngiography, Digital SubtractionCarotid ArteriesRenal ArteryArteriesTesticular DiseasesPopliteal VeinUltrasonography, MammaryGestational AgeHemodynamicsLaser-Doppler FlowmetryImaging, Three-DimensionalPhlebographySeverity of Illness IndexObserver VariationOphthalmic ArteryUterusLower ExtremityVascular Surgical ProceduresHepatic VeinsUltrasonic TherapyPopliteal ArteryNucleic Acid ConformationPortographyOvarian CystsCerebrovascular DisordersPregnancy Trimester, SecondVaricose UlcerFetal Growth RetardationAneurysmEndarterectomy, CarotidROC CurveBlood Vessel Prosthesis ImplantationSulfur HexafluorideRenal Artery ObstructionIntracranial Embolism and ThrombosisMetacarpophalangeal JointSpermatic CordPreoperative CareHepatic ArteryFetal HeartNucleic Acid DenaturationIschemiaGraft Occlusion, VascularTransducersDNAMicrobubblesSubclavian Steal Syndrome