bluuebunny/crossref_metadata_2025_split huggingface dataset:
The prevalence and clinical significance of tricuspid valve regurgitation in normally grown fetuses and those with intrauterine growth retardation
Authors: Gembruch U. , Smrcek J. M. 
Published: March 2003

AbstractThe aim of this study was to assess the prevalence and clinical significance of fetal tricuspid valve regurgitation. In a cross‐sectional study, 289 normally grown singleton fetuses with normal heart anatomy, normal estimated weight for gestational age, normal amniotic fluid volume and normal flow velocity waveforms in the umbilical and middle cerebral arteries and umbilical vein were examined. A further 31 singleton fetuses with intrauterine growth retardation (estimated fetal weight below the 3rd centile) were analyzed. Semiquantification of the tricuspid valve regurgitation by spatial and temporal parameters was performed in the four‐chamber view by color Doppler flow imaging and by color Doppler M‐mode echocardiography (M‐Q mode).The prevalence of fetal tricuspid valve regurgitation among normally grown fetuses was 6.23% (n = 18). In all cases, the tricuspid regurgitation was part‐systolic (non‐holosystolic, early and mid‐systolic tricuspid regurgitation) and showed little spatial expansion of the jet as examined by color Doppler flow imaging (no jet reached the opposite atrial wall, the area of tricuspid regurgitation being less than 25% of the atrial area). The maximum velocity of the regurgitant jets was below 2 m/s with one exception. There was no statistically significant correlation between gestational age and occurrence of tricuspid regurgitation (U test, p > 0.05). Re‐examination of 14 of the 18 fetuses with tricuspid regurgitation showed that tricuspid regurgitation was a transient phenomenon in these instances. The fetal outcome in the presence of tricuspid valve regurgitation was normal. Regurgitations of the mitral, pulmonary and aortic valves were excluded in all 289 fetuses.Only two of the 31 fetuses (6.45%) with intrauterine growth retardation showed tricuspid valve regurgitation. In one fetus the tricuspid regurgitation was only part‐systolic. In the other severely compromised fetus with highly abnormal flow velocity waveforms in the arterial and venous side of the fetal circulation, cardiac dilatation with holosystolic tricuspid and holosystolic mitral regurgitation occurred immediately before intrauterine death.Fetal tricuspid valve regurgitation was a frequent finding during Doppler echocardiography. Although it may be a sign of increased preload, afterload or cardiac dysfunction, in most cases tricuspid valve regurgitation is an isolated transient finding with little temporal and spatial expansion, and it may be physiological. Copyright © 1997 International Society of Ultrasound in Obstetrics and Gynecology
Expression of thymidine phosphorylase in uterine sarcoma and uterine leiomyoma: association with microvessel density and Doppler blood flow analysis
Authors: Hata K. , Hata T. , Iida K. , Miyazaki K. 
Published: March 2003

AbstractThe aim of this study was to determine whether the expression of thymidine phosphorylase (TP) by uterine sarcoma and leiomyoma cells is associated with the density of microvessels within the tumor, and with Doppler ultrasound‐derived peak systolic velocity (PSV) of blood flow.Sections of tissue from four uterine sarcomas and 41 uterine leiomyomas which had been used in a previous study to determine intratumoral peak systolic velocity were analyzed for the cellular expression of TP and the intratumoral density of microvessels by immunohistochemistry, using monoclonai antibody to TP and factor VIII‐related antigen, respectively. The main outcome measures were whether or not the tumor cells were TP‐positive or TP‐negative, and the microvessel count within each tumor typeUterine sarcomata were classified as TP‐positive and uterine leiomyomata as TP‐negative. The microvessel count in uterine sarcomas was significantly higher than that in uterine leiomyomas (p = 0.002, Mann‐Whitney U test).We concluded that the expression of TP by uterine sarcoma cells is associated with an increase in microvessel density and with a higher peak systolic velocity. Copyright © 1997 International Society of Ultrasound in Obstetrics and Gynecology
Effect of the levonorgestrel‐releasing intrauterine system on the uterine artery pulsatility index in postmenopausal hormone replacement therapy
Authors: Järvelä I. , Raudaskoski T. , Tekay A. , Jouppila P. 
Published: March 2003

AbstractThe aim of this study was to determine the effect of continuous intrauterine release of progestin on the uterine artery pulsatility index (PI) in women on postmenopausal hormone replacement therapy (HRT). The voluntary participants, 13 symptomatic postmenopausal women, received transdermal estradiol (50 µg/day) for 1 month before combining the levonorgestrel‐releasing (20 µg/day) intrauterine system (LNG‐IUS) with estrogen replacement therapy. The PI of uterine artery Mood flow was measured by transvaginal color Doppler ultrasonography before the onset of HRT, 1 month after the treatment with estradiol (estradiol‐only phase) and 1, 3 and 6 months after insertion of the LNG‐IUS. The mean uterine artery PI decreased significantly from its pretreatment level after 1 month of transdermal estradiol treatment (p < 0.05), but the LNG‐IUS induced an increase in PI, and 6 months after its insertion the PI did not differ significantly from the pretreatment level (p > 0.05). Compared with the estradiol‐only phase, the last measurement of the PI was significantly increased (p < 0.05). The results suggest that continuous intrauterine release of levonorgestrel abolishes the vasodilatory effect on the uterine arteries accomplished by post‐menopausal estradiol treatment. Copyright © 1997 International Society of Ultrasound in Obstetrics and Gynecology
In vitro volume measurement by three‐dimensional ultrasound: comparison of two different systems
Authors: Hösli I.M. , Tercanli S. , Herman A. , Kretschmann M. , Holzgreve W. 
Published: March 2003

AbstractThe aim of this study was to compare volumetric capabilities in vitro between two different three‐dimensional technical modalities with a transvaginal transducer. We intended to evaluate the effect of different sizes and shapes on the accuracy of the measurements, and to establish criteria for choosing the appropriate system for three‐dimensional volume measurement. We did not find significant differences between the two systems, either in the results or in their operation. We confirmed the high accuracy of three‐dimensional volume measurements in vitro. Copyright © 1998 International Society of Ultrasound in Obstetrics and Gynecology
Conditional centiles for the quantification of fetal growth
Authors: Owen P. , Ogston S. 
Published: March 2003

AbstractA total of 274 low‐risk pregnancies underwent predetermined, scheduled, serial ultrasound examinations and measurement of the biparietal diameter, fetal abdominal area, femur length and estimated fetal weight. The longitudinal nature of this dataset permits the construction of conditional centiles for these measurements, whereby the dimensions of an individual fetus at a given gestational age can be extrapolated to give a range of expected values (expressed as centiles) at a later gestational age. Examples of conditional centiles based upon 4‐week measurement separations are presented. These conditional centiles permit the appropriate quantification and subsequent evaluation of time‐dependent changes in fetal dimensions to be made. Copyright © 1998 International Society of Ultrasound in Obstetrics and Gynecology
Trisomy 22: a cause of isolated fetal growth restriction
Authors: Morrison J. J. , Hastings R. , Jauniaux E. 
Published: March 2003

AbstractThe management of severe isolated fetal growth restriction at term involves consideration of the risk of associated aneuploidy. A case is described in which intrauterine growth restriction was detected at 37 weeks' gestation in a structurally normal fetus. The diagnosis of trisomy 22 was made after fetal blood sampling. This diagnosis has not been previously reported in a structurally normal fetus. This case highlights the dilemma that arises in the management of the small, structurally normal fetus in the late third trimester. The reasons for survival to term of some trisomy 22 fetuses are as yet unclear and are discussed. Copyright © 1998 International Society of Ultrasound in Obstetrics and Gynecology
Doppler parameters of uterine and ovarian stromal blood flow in women with polycystic ovary syndrome and normally ovulating women undergoing controlled ovarian stimulation
Authors: Pinkas H. , Mashiach R. , Rabinerson D. , Avrech O. M. , Royburt M. , Rufas O. , Meizner I. , Ben‐Rafael Z. , Fisch B. 
Published: March 2003

AbstractObjectiveTo test the hypothesis that the increased ovarian sensitivity to gonadotropins observed in women with polycystic ovary syndrome (PCOS) may be due to changes in ovarian stromal blood flow in these patients.DesignUterine and ovarian stromal arterial blood flow (with transvaginal color Doppler ultrasound) were measured in ten women with PCOS and 12 normo‐ovulatory women (control group), undergoing gonadotropin stimulation before in vitro fertilization.MethodsA careful ovarian stimulation strategy was adopted for the study group in order to avoid ovarian hyperstimulation syndrome and achieve an ovarian response which was comparable to that of the control group. Resistance and pulsatility indices (RI and PI) of the uterine and ovarian stromal arteries were calculated before the onset of gonadotropin treatment, on cycle day 5 (after commencing treatment), day of human chorionic gonadotropin injection, day of ovum pick‐up, as well as on the day of embryo transfer, and 7 and 12 days later.ResultsNo significant differences were found in RI and PI between the study and control groups throughout the treatment cycle.ConclusionsIt seems that polycystic ovaries do not bear an inherent disturbance in blood flow dynamics of the uterine and ovarian arteries, as measured by color Doppler, which would explain the increased sensitivity of polycystic ovaries to stimulation with gonadotropins. Copyright © 1998 International Society of Ultrasound in Obstetrics and Gynecology
Expression of thymidine phosphorylase in malignant ovarian tumors: correlation with microvessel density and an ultrasound‐derived index of angiogenesis
Authors: Hata K. , Nagami H. , Iida K. , Miyazaki K. , Collins W. P. 
Published: March 2003

AbstractObjectiveThe aim of this study was to determine whether the expression of thymidine phosphorylase by ovarian cancer cells correlates with the density of microvessels within the tumor, and with ultrasound‐derived indices of blood flow.MethodsTransvaginal ultrasonography with color Doppler imaging and pulsed Doppler spectral analysis was used to scan patients with an overt ovarian mass immediately before laparotomy. Sections of malignant tumors were analyzed for the cellular expression of thymidine phosphorylase and the intratumoral density of microvessels by immunohistochemistry using monoclonal antibodies to thymidine phosphorylase and factor VIII‐related antigen, respectively. The main outcome measures were the histological classification of the tumor, the stage of the disease, whether or not the tumor cells were positive or negative for thymidine phosphorylase, the microvessel count and the peak systolic velocity (PSV).ResultsForty‐two tumors were studied (three of low malignant potential, 29 epithelial, four granulosa cell, two germ cell and four metastatic); 18 were stage I, six stage II, 11 stage III and three stage IV. Twenty‐seven tumors (64%) were classified as thymidine phosphorylase‐positive. The proportion of stage I tumors that was thymidine phosphorylase‐positive (44%) was significantly lower (p = 0.022) than the corresponding value for stages II‐IV (85%), but the values for microvessel count and PSV were similar. The microvessel count in thymidine phosphorylase‐positive tumors was significantly higher than in thymidine phosphorylase‐negative tumors (p = 0.005). Similarly, the PSV was significantly higher in thymidine phosphorylase‐positive tumors (p = 0.009). There was a significant correlation between the microvessel count and the PSV (r = 0.354, p = 0.022).ConclusionsThe expression of thymidine phosphorylase by malignant tumor cells is associated with an increase in microvessel density and PSV in patients with ovarian cancer. Copyright © 1998 International Society of Ultrasound in Obstetrics and Gynecology
Validation of diameter measurements by ultrasound: intraobserver and interobserver variations assessed in vitro and in fetal sheep
Authors: Kiserud T. , Saito T. , Ozaki T. , Rasmussen S. , Hanson M. A. 
Published: March 2003

AbstractObjectivesBlood flow evaluation in the fetus is hampered by inaccuracy in the measurement of vessel diameter. The impact of biological variation on reproducibility studies is unknown. The present study evaluated diameter measurements carried out with modern ultrasound equipment by assessing inter‐ and intraobserver variations.DesignRepeated measurements analyzed by a general factorial model of analysis of variance.MethodsThree observers measured repeatedly (six or more times for each tube and session) silicone tube implants (0.6, 2.2 and 6 mm), applying ultrasound imaging in eight fetal sheep, and the same silicone tubes. Analysis of variance was carried out on 199 observations made and 537 in vivo.ResultsThe upper 95% confidence limit for the intra‐ and interobserver variations was higher for measurements made than. It was highest for the largest diameter and varied between 0.10 and 0.38 mm. When the diameter was determined as an average of repeated measurements, the error was reduced: six measurements in vivo had upper 95% confidence limits for intraobserver variation of 0.04 and 0.09 mm for diameters of 0.6 and 6 mm, respectively.ConclusionsThe results show that ultrasound diameter measurements have a high reproducibility even for vessels of small dimensions when repeated measurements are taken with high‐frequency ultrasound under favorable conditions. The low variation described in the present investigation of silicone tubes, compared to previous studies, suggests that diameter changes of living vessels represent a separate source of measurement variation. Copyright © 1999 International Society of Ultrasound in Obstetrics and Gynecology
The effects of maternal indomethacin therapy on human fetal branch pulmonary arterial vascular impedance
Authors: Rasanen J. , Debbs R. H. , Wood D. C. , Weiner S. , Huhta J. C. 
Published: March 2003

AbstractObjectiveTo examine whether maternal indomethacin therapy affects human fetal pulmonary arterial vascular impedance without constriction of the ductus arteriosus and to determine the changes in the pulmonary arterial vascular impedance in the presence of ductal constriction.Study design In this cross‐sectional study, 52 normal fetuses without maternal medication (control group), 33 fetuses without ductal constriction (Study group I) and 11 fetuses with ductal constriction (Study group II) during maternal indomethacin therapy between 24 and 34 weeks of gestation were examined by Doppler echocardiography. Blood velocity waveforms across the proximal right or left pulmonary artery were obtained and the pulsatility index (PI) of the proximal pulmonary arteries was calculated.ResultsIn the control group, the proximal pulmonary artery PI was higher (p < 0.0001) at 24–25 weeks (n = 7) (3.73 ± 0.33; mean ± SD) than at 33–34 weeks of gestation (n = 11) (2.98 ± 0.27). The PI was constantly greater (p < 0.005) in Study group I than in the control group. However, in this group the mean average weekly decrease in the PI of the proximal pulmonary arteries was similar to that in the control group. After 26 weeks of gestation, the PI values in Study group II were significantly higher than in the control group (27 weeks: 4.12 vs. 3.34 (p < 0.005); 30 weeks: 4.48 vs. 3.14 (p < 0.0001); 34 weeks: 4.96 vs. 3.00 (p < 0.0001), respectively).ConclusionsHuman fetal pulmonary arterial vascular impedance is increased by maternal indomethacin therapy even without ductal constriction. In the presence of ductal constriction, the magnitude of the increase in the vascular impedance is related to the gestational age. Copyright © 1999 International Society of Ultrasound in Obstetrics and Gynecology
First‐trimester cord entanglement in monoamniotic twins
Authors: Overton T. G. , Denbow M. L. , Duncan K. R. , Fisk N. M. 
Published: March 2003

AbstractObjectiveMonoamniotic twinning occurs in only 1% of twin pregnancies, but carries a high perinatal mortality rate. Early and reliable diagnosis is essential if attempts are to be made to reduce the complication rate. We report color Doppler demonstration of cord entanglement in the first trimester, which is diagnostic of monoamnionicity.MethodsTwo patients with twin pregnancies were examined in the first trimester with pulsed and color Doppler insonation of their umbilical arteries.ResultsCord entanglement was suspected and proved by demonstrating differing fetal heart rate patterns in the same direction on umbilical artery Doppler analysis of a common mass of cord vessels. Following appropriate counselling, medical amnioreduction was induced at 20 weeks of gestation to reduce fetal movements and worsening cord entanglement. Delivery was by elective Cesarean section at 32 weeks' gestation and monoamnionicity was confirmed.ConclusionWe report a new sign for the demonstration of monoamnionicity in twin pregnancies in the first trimester. This should improve the reliability of early diagnosis, but further studies are required to confirm that, if cord entanglement occurs, it is usually present by the end of the first trimester. Copyright © 1999 International Society of Ultrasound in Obstetrics and Gynecology
Prenatal sonographic features of spondylocostal dysostosis and diaphragmatic hernia in the first trimester
Authors: Lam Y. H. , Eik‐Nes S. H. , Tang M. H. Y. , Lee C. P. , Nicholls J. M. 
Published: March 2003

AbstractSpondylocostal dysostosis is a congenital disorder characterized by multiple malformations of the vertebrae and ribs. We describe the sonographic features of an affected fetus at 12 and 14 weeks of gestation. The fetus had thoracic scoliosis, multiple vertebral and rib malformations and a grossly dilated stomach that had herniated into the chest through a left‐sided diaphragmatic hernia. The stomach spanned the whole length of the fetal trunk. Copyright © 1999 International Society of Ultrasound in Obstetrics and Gynecology
A screening program for trisomy 21 at 10–14 weeks using fetal nuchal translucency, maternal serum free β‐human chorionic gonadotropin and pregnancy‐associated plasma protein‐A
Authors: Spencer K. , Souter V. , Tul N. , Snijders R. , Nicolaides K. H. 
Published: March 2003

AbstractObjectiveTo examine the potential impact of combining maternal age with fetal nuchal translucency thickness and maternal serum free β‐human chorionic gonadotropin (β‐hCG) and pregnancy‐associated plasma protein‐A (PAPP‐A) in screening for trisomy 21 at 10–14 weeks of gestation.MethodsMaternal serum free β‐hCG and PAPP‐A were measured by Kryptor, a random access immunoassay analyzer using time‐resolved amplified cryptate emission, in 210 singleton pregnancies with trisomy 21 and 946 chromosomally normal controls, matched for maternal age, gestation and sample storage time. In all cases the fetal crown–rump length and nuchal translucency thickness had been measured by ultrasonography at 10–14 weeks of gestation and maternal blood had been obtained at the time of the scan. The distributions (in multiples of the median; MoM) of free β‐hCG and PAPP‐A (corrected for maternal weight) and fetal nuchal translucency (NT) were determined in the trisomy 21 group and the controls. Likelihood ratios for the various marker combinations were calculated and these were used together with the age‐related risk for trisomy 21 in the first trimester to calculate the expected detection rate of affected pregnancies, at a fixed false‐positive rate, in a population with the maternal age distribution of pregnancies in England and Wales.ResultsIn a population with the maternal age distribution of pregnancies in England and Wales, it was estimated that, using the combination of maternal age, fetal nuchal translucency thickness and maternal serum free ß‐hCG and PAPP‐A, the detection of trisomy 21 pregnancies would be 89% at a fixed false‐positive rate of 5%. Alternatively, at a fixed detection rate of 70%, the false‐positive rate would be 1%. The inclusion of biochemical parameters added an additional 16% to the detection rate obtained using NT and maternal age alone.ConclusionsRapid diagnostic technology like Kryptor, which can provide automated reproducible biochemical measurements within 30 min of obtaining a blood sample, will allow the development of interdisciplinary one‐stop clinics for early fetal assessment. Such clinics will be able to deliver improved screening sensitivity, rapidly and more efficiently, leading to reduced patient anxiety and stress. Copyright © 1999 International Society of Ultrasound in Obstetrics and Gynecology
Non‐invasive detection of alterations of the carotid artery in pregnant women with high‐frequency ultrasound
Authors: Sator M. O. , Joura E. A. , Gruber D. M. , Obruca A. , Zeisler H. , Egarter C. , Huber J. C. 
Published: March 2003

AbstractObjectiveTo compare the thickness of the layers of the carotid artery wall in pregnant and fertile non‐pregnant women.DesignProspective cross‐sectional study.SubjectsFifty‐one pregnant women at a mean gestational age of 38.9 weeks and 64 fertile non‐pregnant women were examined at a University hospital.MethodsThe three layers (adventitia, media, intima) of the superficial wall of the left common carotid artery were identified and measured with high‐resolution ultrasound (22.5 MHz).ResultsPregnant women had a thinner intima layer (0.25 ± 0.07/0.29 ± 0.08 mm) and a thicker media layer (0.31 ± 0.08/0.27 ± 0.09 mm) compared with controls. A statistically significantly higher intima/media ratio was calculated for the pregnant women (1.14 ± 0.03), compared with the non‐pregnant women (0.88 ± 0.04).ConclusionThere are differences in the thickness of the histological layers of the carotid artery wall in pregnant compared with non‐pregnant women. This is likely to be due to the effect of different estradiol levels in these two groups. Copyright © 1999 International Society of Ultrasound in Obstetrics and Gynecology