TY - CHAP M1 - Book, Section TI - FETAL CEREBRAL CIRCULATION A1 - Pooh, Ritsuko K. A1 - Degani, Shimon A2 - Timor-Tritsch, Ilan E. A2 - Monteagudo, Ana A2 - Pilu, Gianluigi A2 - Malinger, Gustavo Y1 - 2017 N1 - T2 - Ultrasonography of the Prenatal Brain, 3e AB - KEY POINTSData collected from Doppler velocity recordings using both spectral and color Doppler mode confirm the fundamental aspects of the fetoplacental circulation. Changes in placental vascular resistance, cardiac contractibility, vessel compliance, and blood viscosity alter the normal dynamics of fetal cerebral circulation.Reference values have been established for the main cerebral vessels. During the last trimester of normal pregnancies, the values of Doppler waveform indices decrease in all main cerebral vessels. After birth, vascular resistance decreases, and later stabilizes. Cerebral autoregulation persists from fetal to postnatal life, with low waveform indices in cerebral vessels of growth-retarded fetuses and neonates. The low indices indicate decreased cerebrovascular resistance, representing the redistribution of flow, or the brain-sparing effect.Combined parameters recorded from different vascular beds may provide support for the diagnosis of significant hemodynamic changes and are of prognostic value in predicting fetal outcome such as fetal IUFGR and Rh disease.As far as imaging of the vascularization (arterial and venous) of the prenatal brain, it should be clear that no brain scan should be considered complete without looking at its main vessels or at least at the pericallosal artery on a median section. Should such a protocol be too complicated to achieve in all anomaly scans, it is important to scrutinize brain vascularization in each and every case of suspected brain anomaly.Three-dimensional power Doppler US technology, especially combined with high-frequency TVS, as described in this and other chapters, is the most preferable noninvasive and reproducible imaging method to be used. The accurate information about deviant brain vascularity may help to render proper obstetric, neurologic, and neurosurgical management. SN - PB - McGraw-Hill Education CY - New York, NY Y2 - 2024/03/29 UR - obgyn.mhmedical.com/content.aspx?aid=1138380813 ER -