Fetal cerebral cortex: normal gestational landmarks identified using prenatal MR imaging.

BACKGROUND AND PURPOSE: Few investigators have analyzed the MR imaging patterns of fetal gyration. Our purpose was to establish, with a large prospective series, the normal sulcation landmarks according to gestational age by using in utero MR imaging and to correlate our findings with established neuroanatomic timetables. METHODS: A standardized fetal cerebral MR examination was performed in 173 normal fetuses at 22 to 38 weeks' gestation. Eight T1- and T2-weighted coronal, axial, and sagittal slices were obtained for each fetus and systematically analyzed. The sequential development of the different fissures and sulci of the cerebral cortex with respect to gestational age were tabulated. RESULTS: Sulcation of the medial, lateral, and inferior surfaces of the brain was depicted, and a timetable for the MR depiction of the primary and secondary sulci was established for the 22- to 38-week gestational period. This timetable was in good agreement with the neuroanatomic standards of reference, with a mean lag time of 1 week. CONCLUSION: This analysis of fetal brain sulcation in a large series of fetuses contributes to a better understanding of the maturation of the fetal cortex on MR imaging studies. It furthermore provides a standard of reference that can be used to assess the normality of fetal sulcation and to diagnose gyrational abnormalities with prenatal MR imaging.

[Epidural anaesthesia associated with induction of labour. A clinical study. Electronic monitoring of the physical and biological parameters (author's transl)]. / L'analgésie péridurale associée au déclenchement du travail. Etude clinique. Surveillance électronique des paramètres physiques et biologiques.

73 case histories of induction of labour under epidural anaesthesia have been studied very thoroughly from the different parameters of the uterine contractions as well as the fetal heart rate and the acid base balance of the fetus. From this study it is clear that the basal tone, the intensity and the frequency of contractions and the activity of the uterus are increased in comparison with different studies of normal labour. This increase however is within physiological limits and does not change in any marked way the cardiac rhythm nor the acid base balance of the fetus. The Apgar score at birth is equal to or above 8 in 89 p. 100 of cases at 1 minute and in 100 p. 100 of cases at 5 minutes. Finally, in the last phases of the labour dilatation is quicker than in normal delivery. It follows therefore that maternal comfort has not been bought at the expense of the fetus.