Assessment of the fetal cerebral circulation provides important information on the hemodynamic changes associated with chronic hypoxia and intrauterine growth restriction. Despite the incorporation of new US parameters, the landmark for the fetal brain hemodynamic evaluation is still the middle cerebral artery. However, new vascular territories, such as the anterior and posterior cerebral arteries, might provide additional information on the onset of the brain sparing effect. The fractional moving blood volume estimation and three-dimensional power Doppler ultrasound indices are new techniques that seem to be promising in identifying cases at earlier stages of vascular deterioration; still, they are not available for clinical application and more information is needed on the reproducibility and advantages of three-dimensional power Doppler ultrasound blood flow indices. In the past, the brain sparing effect was considered as a protective mechanism; however, recent information challenges this concept. There is growing evidence of an association between brain sparing effect and increased risk of abnormal neurodevelopment after birth. Even in mild late-onset intrauterine growth restriction affected fetuses with normal umbilical artery blood flow, increased cerebral blood perfusion can be associated with a substantial risk of abnormal neuroadaptation and neurodevelopment during childhood.

Objectives: To evaluate the feasibility and reproducibility of fetal brain volume segmentation and to estimate differences in the volume of intracranial structures between intrauterine growth restricted (IUGR) and adequate for gestational (AGA) age fetuses. Methods: Total intracranial (TIC), frontal (FR), thalamic (THAL) and cerebellar (CER), volumes were measured using 3-D ultrasound and Virtual Organ Computer-aided Analysis, (VOCAL) in 39 IUGR and 39 AGA fetuses matched by gestational age. Volumes of and ratios between intracranial structures were estimated and differences between the groups calculated. Results: All volumes (TIC, CER, FR) except THAL (P = 0.23) were significantly lower (P < 0.001) in IUGR fetuses. After adjusting volumes for biparietal diameter (BPD) only the frontal lobe volume was significantly lower (P = 0.021) in IUGR fetuses as compared to AGA fetuses. Ratios of the different volumes to HC and BPD were significantly lower in IUGR than AGA fetuses with the exception of the thalamic area. No differences in ratios between the structures were observed between the two groups. Interclass correlation coefficients were 0.97, 0.76, 0.66 and 0.47 for THAL TIC, CER and FR, respectively Conclusions: Volume brain segmentation can be performed with a moderate to high reproducibility. IUGR fetuses have reduced volumes of different intracranial structures when compared with AGA fetuses. These differences are maintained only at the frontal lobe when volumes are adjusted by head biometry. OC038 Sonographic assessment of the normal fetal secondary palate using a novel three-dimensional ultrasound approach Objectives: The aim of this study is to describe a three-dimensional (3D) ultrasound rendering technique to examine the normal fetal secondary palate and to assess its correlation to the real fetal anatomy. Methods: A prospective study was leaded and included 122 fetuses in a low risk population. Fetal ultrasound examinations were performed at 17, 22, 27 and 32 weeks' gestation to determine the normal 3D view of the fetal palate at different gestational ages. The ultrasound scan was performed using strict anterior axial plane of starting reconstruction volume. 3D underside view was obtained. The visualization rates of seven defined anatomical landmarks of the palate are computed for each gestational age. The 3D-view of the fetal secondary palate was compared to the normal anatomic view obtained by surgical foetopathologist examination of fetuses. The visualization rates across gestational ages are compared by use of the Cochrane Q test. The reliability of detection of each anatomical landmark across gestational ages is determined by Cronbach's Alpha. To examine the fetal soft tissues, ultrasound scans were studied at 22 weeks of gestation. The sonographer used an 30 •-inclinated axial 3D-view of the fetal palate. The visualization rates of the uvula and the velum were studied. Results: An anatomic 3D ultrasound view of the fetal secondary palate was obtained at each period of gestation with high anatomic c...

This Minireview discusses the progress made in developing reactions where an olefin is subjected to an asymmetric halogenation. It aims to serve as a reference for the studies reported to date, including preliminary work and mechanistic studies. The current state of the art, scope, and limitations of these processes are discussed.

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Response to "Doppler evaluation of the posterior cerebral artery in normally grown and growth restricted fetuses"We appreciate the constructive comments of Dr Morales Rosello et al. to our paper 'Doppler evaluation of the posterior cerebral artery in normally grown and growth restricted fetuses'. We are also very grateful for the phylogenetic explanation on the development of the vascular segments of the cranial arteries. We would like to clarify some points and make some additional comments. We have been evaluating the major cerebral arteries in intrauterine growth restricted fetuses using not only spectral Doppler, but also power Doppler for evaluation of blood perfusion using a technique named Fractional Moving Blood Volume. 1-3 Our results consistently show that the frontal lobe and anterior cerebral artery are affected before the middle cerebral artery. 1,2 We were able to document earlier changes in the posterior cerebral artery than in the middle cerebral artery, 1 data that were confirmed in the present study. 4 However, we still cannot conclude that the hierarchical deterioration always starts in the anterior cerebral artery, it might be possible that the posterior cerebral artery and, most important, the vertebral arteries might be affected first. The contribution of the vertebral system to the process of brain blood flow redistribution has been systematically forgotten, only few papers are available on changes in the vertebral arteries in intrauterine growth restricted fetuses. [5][6][7] Our opinion is that the vertebral artery should be included in the complete hemodynamic evaluation of the fetal cranial circulation.