Prospective navigator-echo-based real-time triggering of fetal head movement for the reduction of artifacts

The purpose of this study was to evaluate the neuroimaging quality and accuracy of prospective real-time navigator-echo acquisition correction versus untriggered intrauterine magnetic resonance imaging (MRI) techniques. Twenty women in whom fetal motion artifacts compromised the neuroimaging quality of fetal MRI taken during the 28.7 ± 4week of pregnancy below diagnostic levels were additionally investigated using a navigator-triggered half-Fourier acquired single-shot turbo-spin echo (HASTE) sequence. Imaging quality was evaluated by two blinded readers applying a rating scale from 1 (not diagnostic) to 5 (excellent). Diagnostic criteria included depiction of the germinal matrix, grey and white matter, CSF, brain stem and cerebellum. Signal-difference-to-noise ratios (SDNRs) in the white matter and germinal zone were quantitatively evaluated. Imaging quality improved in 18/20 patients using the navigator echo technique (2.4 ± 0.58 vs. 3.65 ± 0.73 SD, p < 0.01 for all evaluation criteria). In 2/20 patients fetal movement severely impaired image quality in conventional and navigated HASTE. Navigator-echo imaging revealed additional structural brain abnormalities and confirmed diagnosis in 8/20 patients. The accuracy improved from 50% to 90%. Average SDNR increased from 0.7 ± 7.27 to 19.83 ± 15.71 (p < 0.01). Navigator-echo-based real-time triggering of fetal head movement is a reliable technique that can deliver diagnostic fetal MR image quality despite vigorous fetal movemen

Longitudinal umbilical vein blood flow changes in normal and growth-retarded fetuses

Objective. To explore whether the umbilical vein blood flow of growth-retarded fetuses with normal Doppler parameters changes over time differently to that of normally grown fetuses. Methods. Fifteen consecutive women whose fetus was diagnosed to be growth restricted were compared with 30 women whose fetus was normally grown. Two ultrasonographic evaluations were conducted at 2-weekly intervals (± 2 days) in all cases. At each sonographic evaluation, umbilical vein blood flow parameters were obtained by digital color Doppler velocity profile integration. To allow comparisons among fetuses, the umbilical vein blood flow per minute was normalized for abdominal circumference. Results. The absolute vein blood flow was lower in growth-retarded than in normally grown fetuses (209 ml/min ± 73 vs. 313 ml/min ± 72, p &lt; 0.01). The median (range) umbilical vein blood flow normalized for abdominal circumference was significantly lower in growth-retarded than in normally grown fetuses at the first [0.70 (0.32; 1.15) vs. 1.11 (0.65; 2.07), p &lt; 0.05] and at the second [0.71(0.30; 1.09) vs. 1.14 (0.69; 2.05), p &lt; 0.05] sonographic evaluation. The difference in umbilical vein blood flow normalized for abdominal circumference between the second and the first examination was significantly lower in growth-retarded than in appropriate for gestational age fetuses [-0.005 (-0.08; 0.06) vs. 0.02 (-0.08; 0.1), p &lt; 0.05]. Conclusion. This study demonstrates that umbilical vein blood flow normalized for biometric parameters is lower in growth-retarded fetuses than in healthy fetuses even in the absence of umbilical artery Doppler abnormalities

Umbilical endometriosis

We report two women who presented with a recurrent, mildly painful, bluish nodule in the umbilicus. Both patients complained of local tenderness and occasional bleeding that increased during menstruation. Neither patient had had previous pelvic surgery. Excision of the lesions revealed a primary umbilical endometriosis; in one case, a simultaneous laparoscopy showed a pelvic endometriosis. We review the current literature and discuss the possible etiopathogenesis and when a laparoscopy is indicated to diagnose a concomitant pelvic endometriosis. Umbilical endometriosis is a very rare disease but should be considered in the differential diagnosis of umbilical lesion

Ductus venosus blood flow velocity characteristics of fetuses with single umbilical artery

Objectives: Sonographic Doppler evaluation of the fetal ductus venosus has been proved to be useful in the evaluation of fetal cardiac function. The aim of this study was to investigate the ductus venosus blood flow profile in fetuses with single umbilical artery and to correlate it with the umbilical cord morphology. Methods: Fetuses at > 20 weeks' gestation with single umbilical artery who were otherwise healthy were consecutively enrolled into the study. The sonographic examination included evaluation of the following Doppler parameters: umbilical artery resistance index, maximum blood flow velocity of the ductus venosus during ventricular systole (S-peak) and atrial contraction (A-wave), ductus venosus time-averaged maximum velocity (TAMXV), and pulsatility index for veins (PIV). The cross-sectional area of the umbilical cord and its vessels were measured in all cases. The Doppler and morphometric values obtained were plotted on reference ranges. Results: A total of 88 fetuses with single umbilical artery were scanned during the study period. Of these 52 met the inclusion criteria. The S-peak velocity, A-wave velocity, and TAMXV were below the 5th centile for gestational age in 57.7%, 59.6%, and 57.7% of cases, respectively. The PIV was within the normal range in 80.1% of cases. The umbilical vein cross-sectional area of fetuses with single umbilical artery was above the 95th centile for gestational age in 34.6% cases. Conclusions: The ductus venosus blood flow pattern is different in fetuses with single umbilical artery from that in those with a three-vessel cord. This difference may be caused in part by the particular morphology of umbilical cords with a single artery. Copyright © 2003 ISUOG. Published by John Wiley & Sons, Ltd

Umbilical vein blood flow in fetuses with normal and lean umbilical cord

Objective: To evaluate whether umbilical vascular coiling is correlated with the umbilical vein blood flow profile and to investigate if this is different between fetuses with a lean and those with a normal umbilical cord. Methods: Consecutive women with a singleton gestation who delivered at term and who underwent an ultrasound examination within 24 h from delivery were studied. Umbilical cord and vessel areas were calculated. Umbilical vein blood flow parameters were obtained by digital color Doppler velocity profile integration. After delivery, the umbilical coiling index was calculated. Results: One hundred and sixteen women were studied. Twelve (10.3%) had a lean umbilical cord (area &lt; 10th centile). A significant correlation was found between the umbilical coiling index and the umbilical vein blood flow (r = 0.67, P &lt; 0.001). A significant difference between fetuses with and without a lean cord was found in terms of: umbilical coiling index (0.18 ± 0.08 vs. 0.29 ± 0.09, P &lt; 0.005), cord area (87.6 ± 5.1 mm2 vs. 200.6 ± 34.6 mm2, P &lt; 0.001), Wharton's jelly amount (25.7 ± 10.3 mm2 vs. 122.1 ± 33.4 mm2, P &lt; 0.001), umbilical vein blood flow (93.7 ± 17.8 ml/kg per min vs. 126.0 ± 23.4 ml/kg per min, P &lt; 0.001), and umbilical vein blood flow mean velocity (6.6 ± 2.7 cm/s vs. 9.0 ± 3.6 cm/s, P &lt; 0.05). The proportion of fetuses with an umbilical vein blood flow &lt; 80 ml/kg per min was higher when the cord was lean than when it was normal (25% vs. 1.9%, P &lt; 0.01). Conclusions: Lean umbilical cords differ from normal cords not only from a structural point of view but also in the umbilical vein blood flow characteristics. This could explain the increased incidence of intrapartum complications and fetal growth restriction among fetuses with a lean and/or hypocoiled cord

Prenatal diagnosis of a lean umbilical cord: A simple marker for the fetus at risk of being small for gestational age at birth

Objective. The purpose of this study was to investigate whether the prenatal diagnosis of a 'lean' umbilical cord in otherwise normal fetuses identifies fetuses at risk of being small for gestational age (SGA) at birth and of having distress in labor. The umbilical cord was defined as lean when its cross-sectional area on ultrasound examination was below the 10th centile for gestational age. Method. Pregnant women undergoing routine sonographic examination were included in the study. Inclusion criteria were gestational age greater than 20 weeks, intact membranes, and singleton gestation. The sonographic cross-sectional area of the umbilical cord was measured in a plane adjacent to the insertion into the fetal abdomen. Umbilical artery Doppler waveforms were recorded during fetal apnea and fetal anthropometric parameters were measured. Results. During the study period, 860 patients met the inclusion criteria, of whom 3.6% delivered a SGA infant. The proportion of SGA infants was higher among fetuses who had a lean umbilical cord on ultrasound examination than among those with a normal umbilical cord (11.5% vs. 2.6%, p < 0.05). Fetuses with a lean cord had a risk 4.4-fold higher of being SGA at birth than those with a normal umbilical cord. After 25 weeks of gestation, this risk was 12.4 times higher when the umbilical cord was lean than when it was of normal size. The proportion of fetuses with meconium-stained amniotic fluid at delivery was higher among fetuses with a lean cord than among those with a normal umbilical cord (14.6% vs. 3.1%, p < 0.001). The proportion of infants who had a 5-min Apgar score < 7 was higher among those who had a lean cord than among those with normal umbilical cord (5.2% vs. 1.3%, p < 0.05). Considering only patients admitted in labor with intact membranes and who delivered an appropriate-for-gestational-age infant, the proportion of fetuses who had oligohydramnios at the time of delivery was higher among those who had a lean cord than among those with a normal umbilical cord (17.6% versus 1.3%, p < 0.01). Conclusion. We conclude that fetuses with a lean umbilical cord have an increased risk of being small for gestational age at birth and of having signs of distress at the time of delivery

Inter- and intra-observer variability in Sonographic measurements of the cross-sectional diameters and area of the umbilical cord and its vessels during pregnancy

Background. The purpose of the study was to evaluate inter- and intra-observer variability in sonographic measurements of the cross-sectional area of the umbilical cord and the diameters of its vessels in low-risk pregnancies of 12 to 40 weeks of gestation. Methods. A prospective cross sectional study was performed in 221 pregnant women at different gestational ages. Measurements were carried out also by a second observer to evaluate inter-observer variability and repeated once again by the first observer to assess intra-observer variability. The linear correlation between the measurements (Spearman's coefficient of correlation) and their reliability through the intraclass correlation coefficient (ICC), the Cronbach's alpha coefficient and the limits of agreement proposed by Bland and Altman were evaluated. Results. The results showed that inter-observer and intra-observer variability did not show any significant difference between examiners. A good linear correlation between the measurements and reliability was obtained, with values of R, ICC and Cronbach's alpha all above the standard limits. Conclusion. It is possible to conclude that inter- and intra-observer variability in the measurements of the umbilical cord and its vessels was small; their reliability and agreement were good. © 2008 Barbieri et al; licensee BioMed Central Ltd

Detection of Tumorigenic Rhizobia in Asymptomatic Peach Plants by PCR

At present the only method for the detection of Rhizobium radiobacter and R. rhizogenes (ex Agrobacterium tumefaciens) in plants is by isolating the bacteria on selective medium and testing them in vivo for pathogenicity. This procedure is time-consuming and not appropriate for detecting low concentrations of these agrobacteria. In this study a protocol was developed for detecting tumorigenic agrobacteria in the stem and root tissues of artificially inoculated peach plants. DNA was extracted from the plant tissues by a rapid procedure and then a 246 bp sequence of the vir region of the pTi was amplified by PCR. The target sequence was found in all stem and root samples of asymptomatic peach plants, and was evidenced in all the samples analyzed showing the effectiveness and reliability of the method

Fetal Cerebellar Vermis Circumference Measured by 2-Dimensional Ultrasound Scan: Reference Range, Feasibility and Reproducibility.

Purpose: To provide 2-dimensional ultrasonographic (2D-US) normograms of cerebellar vermis biometry, as well as to evaluate the feasibility and the reproducibility of these measurements in clinical practice. Materials and Methods: A prospective cross-sectional study of 328 normal singleton pregnancies between 18 and 33 weeks of gestation. Measurements of the fetal cerebellar vermis circumference (VC) in the mid-sagittal plane were performed by both a senior and a junior operator using 2D-US. VC as a function of gestational age (GA) was expressed by regression equations. In 24 fetuses 3-dimensional (3D) reconstructed planes were obtained in order to allow comparisons with 2D-US measurements. The agreement between 2D and 3D measurements and the interobserver variability were assessed by interclass correlation coefficients (ICC). Results: Satisfactory vermis measurements could be obtained in 89.9% of cases. The VC (constant= - 12.21; slope=2.447; r=0.887, p<0.0001) correlated linearly with GA. A high degree of consistency was observed between 2D and 3D ultrasound measurements (ICC=0.846 95% CI 679-0.930) as well as between measurements obtained by different examiners (ICC=0.890 95% CI 989-0.945). Conclusion: 2-dimensional ultrasonographic measurements of cerebellar vermis throughout gestation in the mid-sagittal view seem to be feasible and reproducible enough to be potentially used in clinical practice. Such measurements may supply a tool for accurate identification of posterior fossa anomalies, providing the basis for proper counseling and management and of these conditions