Doppler ultrasound is a hot topic at the present time. This is because studies of the uteroplacental and fetal circulation give fundamental information as to the physiology or pathology of placental function and the response of the fetal circulation to hypoxaemia. Dr. Arabin's clinical studies which are described in this book are an important contribution to knowledge in this field and will be of enormous interest not only to researches but also to clini­ cians interested in learning how this latest technology can be integrated into their clinical practice. London STUART CAMPBELL Foreword Although only three decades old, the field of perinatal medicine is marked by continuous new advances. Ultrasound diagnostic techniques comprise an important element of this new field. Dr. Arabin has taken the initiative to investigate the functional-diagnostic aspects of ultrasound. Among other things, she has further developed and refined the concept of "oxygen-con­ serving adaptation of fetal circulation" which originated in the Department of Obstetrics and Gynecology at the Neukolln Hospital Center in 1966. She thus has been able to show that the most reliable Doppler blood flow meas­ urement predictors of a high risk to the fetus are (1) a decrease in the flow volume of the descending thoracic aorta and the umbilical artery and (2) an increase in the flow volume of the common carotid arteries.

A practical book on the clinical monitoring of fetal blood flow; it can be used as a reference in daily routine.

1 Introduction.- 1.1 Anatomical and Pathophysiological Principles.- 1.1.1 Uteroplacental Hemodynamics.- 1.1.2 Fetoplacental Hemodynamics.- 1.2 Experimental Blood Flow Measurement in Animal and Clinical Studies.- 1.2.1 Uteroplacental Hemodynamics.- 1.2.2 Fetoplacental and Fetal Hemodynamics.- 1.3 Development of Doppler Blood Flow Measurements.- 2 Methodology.- 2.1 History of the Doppler Principle.- 2.2 Fundamental Physical Principles.- 2.3 The Doppler Technique in Medical Diagnosis.- 2.3.1 The Doppler Spectrum.- 2.3.2 Continuous-Wave Doppler Method.- 2.3.3 Pulsed Doppler Method.- 2.3.4 Processing of the Doppler Signal.- 2.3.5 Safety of Doppler Ultrasound.- 2.4 Description of Our Instrument (Duplex System).- 2.5 Practical Procedure.- 2.5.1 Uteroplacental Vessels.- 2.5.2 Umbilical Artery.- 2.5.3 Fetal Descending Thoracic Aorta.- 2.5.4 Fetal Common Carotid Artery.- 2.6 Evaluation of Doppler Frequency Spectra.- 2.6.1 Quantitative Evaluation: Blood Flow Velocity/Blood Flow Volume.- 2.6.2 Qualitative Evaluation: S/D Ratio, Resistance Index, Pulsatility Index.- 2.7 Patient Material and Measurements.- 2.7.1 Normal Group.- 2.7.2 Group with Follow-Up Studies of the Placenta.- 2.7.3 Risk Group.- 2.8 Data Collection.- 2.9 Statistical Analysis.- 2.9.1 Major Influencing Factors.- 2.9.2 Reproducibility.- 2.9.3 Calculation of Standard Curves.- 2.9.4 Possible Pathophysiological Interrelationships: Correlations Between Blood Flow Parameters and Placental Morphology.- 2.9.5 Assessments of Clinical Significance.- 2.10 Criticism of Method.- 2.10.1 Physiological Variations.- 2.10.2 Display of Doppler Spectrum.- 2.10.3 Vascular Wall Filter.- 2.10.4 Determination of Angle.- 2.10.5 Vessel Diameter.- 2.10.6 Instrument Used in Our Studies (8130 Duplex).- 3 Results.- 3.1 Doppler Blood Flow Measurements in Normal Pregnancy.- 3.1.1 Major Factors Affecting Fetal and Uteroplacental Blood Flow Parameters.- 3.1.2 Reproducibility.- 3.1.3 Normal Values of Uteroplacental and Fetal Blood Flow Parameters.- 3.2 Pathophysiological Significance of Doppler Blood Flow Measurements.- 3.2.1 Correlation Between Blood Flow Parameters and Pathomorphological Findings in the Placenta.- 3.2.2 Blood Flow Parameters in Risk Pregnancies.- 3.3 Clinical Significance of Doppler Blood Flow Measurements.- 3.3.1 Comparison of Diagnostic Values of Blood Flow Parameters.- 3.3.2 Comparison with Other Monitoring Parameters.- 3.3.3 Studies in a Group with Loss of Recordable End-Diastolic Velocity in the Umbilical Artery and/or Fetal Aorta.- 4 Discussion.- 4.1 Physiological Aspects.- 4.1.1 Dependence of Fetal Blood Flow Parameters on Heart Rate and Movement Status.- 4.1.2 Dependence of Uteroplacental Blood Flow Parameters on the Location of the Vessel Relative to the Placenta.- 4.1.3 Reproducibility.- 4.1.4 Normal Values.- 4.2 Pathophysiological Aspects.- 4.2.1 Correlation Between Blood Flow Parameters and Pathomorphological Placental Findings.- 4.2.2 Blood Flow Parameters in Risk Pregnancies.- 4.3 Clinical Aspects.- 4.3.1 Comparison of Blood Flow Parameters.- 4.3.2 Comparison of Different Monitoring Parameters.- 4.3.3 Studies in the Group with Loss of Recordable End-Diastolic Velocity.- 4.3.4 Outlook for Other Obstetrical Uses of Doppler Ultrasound.- 5 Summary.- 6 Conclusions.- References.