Fetal Skull

About: Fetal Skull is a research topic. Over the lifetime, 142 publications have been published within this topic receiving 2886 citations.

Extrusion Of Foods

Abstract: Safety of MR Imaging in Pregnancy. MR Imaging of Normal Brain in the Second and Third Trimesters. MR Imaging of Fetal CNS Abnormalities. MR Imaging of the Fetal Skull, Face, and Neck. MR Imaging of Fetal Thoracic Abnormalities. Imaging of the Fetal Abdomen and Pelvis. MR Imaging of the Fetal Extremities, Spine, and Spinal Cord. MR Imaging of Multiple Gestations. Current Techniques and Future Directions for Fetal MR Imaging. MR Imaging Before Fetal Surgery: Contribution to Management. MR Imaging of the Maternal Abdomen and Pelvis in Pregnancy

Detection of fetal structural abnormalities at the 11-14 week ultrasound scan.

Abstract: The aim of this study was to evaluate the detection of fetal structural abnormalities by the 11-14 week scan. 2853 pregnant women were submitted to a routine ultrasound scan between the 11th and 14th week and the fetal skull, brain, spine, abdominal wall, limbs, stomach and bladder were examined. Following the scans the patients were examined in the second or third trimester of pregnancy. An isolated increased nuchal translucency was not considered an abnormality. However, these patients had an early echocardiography assessment. Fetal structural abnormalities were classified as major or minor and of early or late onset. A total of 130 (4.6%) defects were identified and 29 (22.3%) of these were diagnosed at the 11-14 week scan, including nine cardiac defects associated with increased nuchal translucency. The antenatal ultrasound detection rate was 71.5%, and 31.2% were detected in the first-trimester assessment. 78.8% of the major defects were diagnosed by the prenatal scan and 37.8% by the 11-14 week scan. Fetal structural abnormalities at the 11-14 week scan were detected in approximately 22.3% of the cases, therefore, a second-trimester anomaly scan is important in routine antenatal care to increase the prenatal detection of fetal defects.

Estimating fetal age: effect of head shape on BPD

Abstract: Several recent obstetrical sonographic examinations in this department demonstrated that variations in the shape of the fetal skull (e.g., dolichocephaly, brachycephaly) may adversely affect the accuracy of the biparietal diameter (BPD) measurement in estimating fetal age. In each case the cephalic index of the fetal skull (short axis/long axis x 100) was in either the dolichocephalic or brachycephalic range based on established postnatal criteria. Consequently, normal values were determined (mean, 78.3) for the cephalic index in utero based on 316 obstetrical sonographic studies performed at 14--40 weeks. Preliminary experience indicates that a cephalic index greater than 1 SD from the mean (less than 74, greater than 83) may be associated with a significant alteration in the BPD measurement expected for a given gestational age, and that the head circumference can be used effectively as an alternative means of establishing gestational age.

Development of the skull of Dermophis mexicanus (amphibia: Gymnophiona), with comments on skull kinesis and amphibian relationships.

Abstract: The development of the skull of Dermophis mexicanus (Caeciliidae) is described and compared to that of other caecilians. The chondrocranium is well developed in embryos of 25 mm total length (TL); ossification begins in the quadrate and the articular element of the lower jaw at about 30 mm TL. The occipital arch then ossifies, followed by the dorsal and lateral dermal bones, then the ventral endochondral and dermal elements. The stapes ossifies at 55 mm TL. The amount of skull roofing increases during ontogeny, although the anterior rims of the nasal capsules, the anterior part of the mesethmoid, and the hyoid apparatus remain cartilaginous throughout life. Dermophis mexicanus lacks many primary embryonic ossification centers reported by Marcus et al. ('35) for Hypogeophis; presence of these ossification centers has been presumed to be indicative of a primitive skull morphology derived with little modification from archaic amphibians (“stegocephalians”). The fetal skull is highly kinetic, and some kinesis is retained in adults. We suggest that fetal skull kinesis and early ossification of jaw suspension elements are functionally related to the intraoviducal feeding mode of this viviparous species. Based on this evidence, together with the observed ossification pattern and bone homologies, we conclude that stegokrotaphy (complete skull roofing) in caecilians is a derived condition, correlated with fossoriality, and does not indicate a direct relationship of caecilians to any known early amphibian taxon.