Effect of B-mode optimization techniques on fetal bowel echogenicity using computerized image analysis

OBJECTIVES

The purpose of this study was to provide and compare measurable parameters for normal fetal bowel echogenicity under predefined B-mode scanning presets.

METHODS

Forty healthy fetuses underwent 14- to 17-week ultrasound scans, and 40 underwent 21- to 25-week scans. Sagittal, coronal, and axial fetal abdominal images were tested using predefined B-mode presets. The presets differed from fundamental imaging by isolated activation of harmonic imaging, compound resolution imaging, speckle reduction imaging, focus and frequency composite imaging, and coded excitation imaging features. A transabdominal probe was used in all fetuses, and transvaginal images were added for the 14- to 17-week scans. The images were studied with custom-developed software, which provided a grayscale analysis of the pixels in the region of interest within the image. The mean brightness of the pixels from the fetal bowel area was calculated.

RESULTS

The 14- to 17-week transabdominal scans showed significantly higher mean brightness on harmonic imaging compared to fundamental imaging (P < .01). Activation of coded excitation and compound resolution imaging in these scans resulted in a significant decrease in the mean brightness compared to fundamental imaging. Mean bowel brightness values on the 21- to 25-week transabdominal scans did not differ significantly with the use of the different imaging presets compared to fundamental imaging.

CONCLUSIONS

Transabdominal harmonic imaging in the early second trimester may significantly increase the mean brightness of the fetal bowel tissue. Contrarily, compound resolution imaging and coded excitation imaging produce the opposite effect on bowel echogenicity.

Variations of the origin of renal arteries in the fetus identified on power Doppler and 3D sonography

PURPOSE

To investigate anatomic variations of renal arteries (RAs) using 2-dimensional (2D)/3D power Doppler sonography (PDUS) in normal fetuses and in fetuses with renal anomalies.

METHODS

The origin, direction, and distribution of RAs were studied in 120 fetuses without renal malformations using 2D/3D PDUS. Studies were performed between 14 and 17 weeks of gestation age on 64 male and 56 female fetuses. PDUS of the RAs was also performed in 12 fetuses with renal anomalies.

RESULTS

In 117/120 fetuses, a single RA was found to originate from each side of the abdominal aorta. The origin of the right RA from the abdominal aorta was superior to, at the same level as, and inferior to that of the left RA in 47% (55/117), 25.5% (30/117), and 27.5% (32/117) of the cases, respectively. An accessory right RA was found in 3 cases. Bifurcation of the right RA was found in 2 cases. There were no variations of the origin of renal vessels in 69% of the cases (83/120), whereas the remaining 31% (37/120) had 1 or several variation patterns. Variations in renal vessels were found in 8 of the 12 fetuses with renal malformations: accessory artery in 3 cases, origin of the right RA from the iliac artery in horseshoe kidney and in 2 cases with pelvic kidney, and bifurcation in 2 of the fetuses with double collecting system.

CONCLUSIONS

Variations in origin and distribution of fetal RAs are frequently observed in normal pregnancies. The majority of renal malformations are associated with such vascular variations.

Fetal eyeball volume: relationship to gestational age and biparietal diameter

OBJECTIVE

To measure and determine normal values of the fetal eyeball volume between 14 and 40 weeks of gestation.

METHODS

The volume of the fetal eyeball was measured with three-dimensional ultrasound between 14 and 40 weeks of gestation using the VOCAL software.Only singleton pregnancies without fetal growth restriction, diabetes mellitus, hypertension or major fetal malformation were included.

RESULTS

Over all, 203 women were studied. In 125 both eyeballs were measured while in 78 only one eyeball was measured. The volume of the eyeball correlated strongly with gestational age (right: R = 0.946, P < 0.001, n = 171. left: R = 0.945, P < 0.001, n = 156), and with the biparietal diameter (BPD) (right: R = 0.949, P < 0.001, n = 171. left: R = 0.953, P < 0.001, n = 156). Using regression analysis the best correlation between eyeball volume and the BPD were: square of right eyeball = -0.180 + 0.187 BPD, square of left eyeball = -0.182 + 0.187 BPD.

CONCLUSIONS

The volume of the eyeball has strong positive correlations with gestational age and BPD. Our data may be helpful in fetuses suspected of having eye anomalies.

Evaluation of fetal cerebrovascular circulation and brain development: the role of ultrasound and Doppler

The human fetal brain is protected from pressure changes by autoregulation of the cerebral circulation. However, antenatal intrauterine cerebrovascular events are found to play an important role in the pathogenesis of perinatal brain damage. Changes in placental vascular resistance, cardiac contractibility, vessel compliance, and blood viscosity alter the normal dynamics of fetal cerebral circulation. The introduction of various sonographic techniques and the collection of data from the arterial and venous cerebral circulation provide a powerful tool for the evaluation of physiological and pathological hemodynamic events. Anatomic and physiological considerations of cerebral vasculature in healthy and disease states are relevant in studying brain development and variations in fetal brain blood perfusion. The major role of ultrasound and Doppler modalities in the evaluation of fetal cerebrovascular circulation is enabled by implementation of these considerations. Changes in flow characteristics in fetal cerebral vasculature can be used for clinical decision making in situations of fetal compromise, such as growth restriction and anemia.

[Ultrasound in the evaluation of intrauterine infection during pregnancy]

Ultrasound has an important role in the detection and follow- up of intrauterine infection. Viral infections are a major cause of fetal morbidity and mortality. Transplacental transmission of the virus, even in sub-clinical maternal infection, may result in a severe congenital syndrome. Prenatal detection of viral infection is based on fetal sonographic findings and PCR to identify the specific infectious agent. Most affected fetuses appear sonographically normal, but serial scanning may reveal evolving findings. Common sonographic abnormalities, although non-specific, may be indicative of fetal viral infections. These include growth restriction, ascites, hydrops, ventriculomegaly, intracranial calcifications, hydrocephaly, microcephaly, cardiac anomalies, hepatosplenomegaly, echogenic bowel, placentomegaly and abnormal amniotic fluid volume. Some of the pathognomonic sonographic findings enable diagnosis of a specific congenital syndrome (e.g., ventriculomegaly and intracranial and hepatic calcifications in cytomegalovirus or in toxoplasma; eye and cardiac anomalies in congenital Rubella syndrome; limb contractures and cerebral anomalies in Varicella Zoster virus). When abnormalities are detected on ultrasound, a thorough fetal evaluation is recommended because of multiorgan involvement.

Fetal cerebrovascular circulation: a review of prenatal ultrasound assessment

Antenatal intrauterine cerebrovascular events were found to play an important role in the pathogenesis of perinatal brain damage. Changes in placental vascular resistance, cardiac contractibility, vessel compliance, and blood viscosity alter the normal dynamics of fetal cerebral circulation. The circulatory mechanisms described in animal fetuses also operate in the human fetus. The isthmus of the aorta represents a watershed area reflecting the redistribution of blood during increased peripheral resistance and hypoxia. The fetal cerebrovascular system acts locally within the skull and interacts with the other components of fetal circulation to compensate by redistribution of blood in case of shortage in resources. The introduction of various sonographic techniques and the collection of data from the arterial and venous cerebral circulation have improved our understanding of the regulatory mechanisms involved in fetal cerebral hemodynamic events. Anatomical and physiological considerations of cerebral vasculature in health and disease are relevant in the research of variations in fetal brain blood perfusion. Changes in flow characteristics in fetal cerebral vasculature can be used for clinical decisions. However, caution is advised before applying research data into practice. The clinical utility is well established in situations of fetal compromise such as growth restriction and anemia.

Three-dimensional sonographic volumetry of the gestational sac and the amniotic sac in the first trimester

OBJECTIVE

The purpose of this study was to measure the volumes of the gestational sac and amniotic sac in normal pregnancies during the first trimester with 3-dimensional sonography to prepare nomograms.

METHODS

One hundred fifty-one patients between 6 and 12 weeks' gestation were studied. Nine aborted and were excluded, leaving 142 patients for evaluation. Inclusion criteria were a singleton viable pregnancy shown by transvaginal sonography and continuation of the pregnancy beyond 24 weeks. Women with known thrombophilia or fetal malformations were excluded. In all patients, gestational sac and amniotic sac volumes were measured by 3-dimensional transvaginal sonography with virtual organ computer-aided analysis software.

RESULTS

The mean gestational sac volume was 20.35 mL (range, 0.7-113 mL) and correlated closely with the gestational age (GA) (r2 = 0.769; P << .001) and crown-rump length (CRL) (r2 = 0.823; P << .001). The mean amniotic sac volume was 3.69 mL (range, 0.01-92.1 mL) and also had a strong correlation with the GA (r2 = 0.869; P << .001) and CRL (r2 = 0.919; P << .001).

CONCLUSIONS

Gestational sac and amniotic sac volumes show excellent correlation with the GA and CRL and hence may be used for determining the GA. Larger studies are needed to determine the importance of these volumes in predicting normal pregnancy outcomes and whether these volumes can be used in the management of pregnancies at risk for abortion.

Fetal weight estimation for prediction of fetal macrosomia: does additional clinical and demographic data using pattern recognition algorithm improve detection?

OBJECTIVE

The aim of this study was to test whether pattern recognition classifiers with multiple clinical and sonographic variables could improve ultrasound prediction of fetal macrosomia over prediction which relies on the commonly used formulas for the sonographic estimation of fetal weight.

METHODS

THE SVM ALGORITHM WAS USED FOR BINARY CLASSIFICATION BETWEEN TWO CATEGORIES OF WEIGHT ESTIMATION: >4000gr and <4000gr. Clinical and sononographic input variables of 100 pregnancies suspected of having LGA fetuses were tested.

RESULTS

Thirteen out of 38 features were selected as contributing variables that distinguish birth weights of below 4000gr and of 4000gr and above. Considering 4000gr. as a cutoff weight the pattern recognition algorithm predicted macrosomia with a sensitivity of 81%, specificity of 73%, positive predictive value of 81% and negative predictive value of 73%. The comparative figures according to the combined criteria based on two commonly used formulas generated from regression analysis were 88.1%, 34%, 65.8%, 66.7%.

CONCLUSIONS

The SVM algorithm provides a comparable prediction of LGA fetuses as other commonly used formulas generated from regression analysis. The better specificity and better positive predictive value suggest potential value for this method and further accumulation of data may improve the reliability of this approach.

Three-dimensional power Doppler in the evaluation of painful leiomyomas and focal uterine thickening in pregnancy

OBJECTIVE

To determine the usefulness of 3-dimensional (3D) power Doppler ultrasound in distinguishing painful leiomyomas from focal myometrial contractions or nonpainful leiomyomas in pregnancy.

METHODS

A 2D section of the area of interest in the uterine wall was first obtained in 29 patients to determine whether the pain originated from a myoma or a uterine contraction. Then, volume acquisition was activated and Doppler indices (vascularization index, flow index, and vascularization-flow index) were calculated for thickened and normal uterine wall.

RESULTS

Of 15 patients found to have uterine myomas, 11 had multiple tumors and 4 had single tumors. In the remaining 14 patients the painful uterine thickening proved to be a focal contraction. Painful segments of uterine thickening were associated with lower Doppler indices. Painful myomas were found to have significantly lower indices than normal uterine wall (P=0.008, 0.03, and 0.01 for VI, FI, and VFI, respectively, vs. 0.001, 0.003, and 0.01). However, the differences in indices between nonpainful myomas and uterine wall on the one hand, and nonpainful myomas and focal uterine contractions on the other, were not statistically significant.

CONCLUSION

Three-dimensional power Doppler ultrasound may be a sensitive and reliable tool for distinguishing painful uterine myomas from focal myometrial contractions and nonpainful myomas.

Complication of laparoscopic detorsion of adnexal mass

Detorsion of an ischemic adnexal mass has recently been advocated for most cases of twisted adnexa. Usually, the affected ovary regains some or all of its vitality and function. However, when the ovary is completely necrotic, it may form an abscess if it contains tissue components that cannot be eliminated by the peritoneal immune system. We report a case of pelvic abscess formation in a detorsed ovary that previously contained an unsuspected dermoid cyst. We call for an extensive inspection of the detorsed ovary before ending the laparoscopic operation, and if it remains necrotic and is suspected of containing a dermoid cyst, it should be removed promptly.

The use of pulsed-wave Doppler in prenatal diagnosis. An update

Pulsed wave Doppler ultrasound of fetal vessels confirms the similarity of human fetal circulation to the experimental animal physiology, The result of a multitude of research articles in this field is the clinical use of various components of fetal circulation in perinatal medicine. Umbilical, uterine and fetal cerebral arteries as well as the fetal venous circulation show the potential of Doppler ultrasonography.

Sonographic Findings in Fetal Viral Infections: A Systematic Review

Viral infections are a major cause of fetal morbidity and mortality. Transplacental transmission of the virus, even in subclinical maternal infection, may result in a severe congenital syndrome. Prenatal detection of viral infection is based on fetal sonographic findings and polymerase chain reaction to identify the specific infectious agent. Most affected fetuses appear sonographically normal, but serial scanning may reveal evolving findings. Common sonographic abnormalities, although nonspecific, may be indicative of fetal viral infections. These include growth restriction, ascites, hydrops, ventriculomegaly, intracranial calcifications, hydrocephaly, microcephaly, cardiac anomalies, hepatosplenomegaly, echogenic bowel, placentomegaly, and abnormal amniotic fluid volume. Some of the pathognomonic sonographic findings enable diagnosis of a specific congenital syndrome (eg, ventriculomegaly and intracranial and hepatic calcifications in cytomegalovirus, eye and cardiac anomalies in congenital rubella syndrome, limb contractures and cerebral anomalies in varicella zoster virus). When abnormalities are detected on ultrasound, a thorough fetal evaluation is recommended because of multiorgan involvement.

TARGET AUDIENCE

Obstetricians & Gynecologists, Family Physicians.

LEARNING OBJECTIVES

After completion of this article, the reader should be able to recall that both clinical and subclinical maternal viral infections can cross the placenta, explain that there are specific sonographic findings along with laboratory findings to detect infectious agents, and state that when sonographic abnormalities are detected fetal viral infections need to be considered.

Instability of Doppler cerebral blood flow in monochorionic twins

OBJECTIVE

The purpose of this study was to evaluate Doppler flow velocity changes in cerebral vessels of monochorionic twins with twin-twin transfusion syndrome (TTTS).

METHODS

Repeated Doppler umbilical and cerebral blood flow studies were performed in 7 twin pairs with TTTS. Eight monochorionic twin pairs and 11 dichorionic twin pairs served as control groups. The following Doppler parameters were assessed: umbilical artery pulsatility index (PI), middle cerebral artery (MCA) PI, cerebroplacental ratio, delta PI between the umbilical artery and MCA, and peak systolic velocity (PSV) in the MCA.

RESULTS

Significant variations in PSV in the MCA and cerebral indices were found in the study group of monochorionic twins with TTTS. Periods of high PSV with low PI in the MCA were followed by lower PSV in the same fetus. Repeated measurements in the comparison groups were stable without significant variations. The delta cerebroplacental ratio was significantly higher in the study group (0.38 versus 0.09 and 0.19 in the comparison groups; P < .02).

CONCLUSIONS

Significant changes in Doppler flow velocity and indices suggest instability of cerebral blood flow with episodes of "hyperperfusion" in monochorionic twins with TTTS. Further studies are needed to elucidate the relationship of these transient changes to neurologic sequelae in the neonate.

Decidualization of ovarian endometriosis during pregnancy mimicking malignancy

OBJECTIVE

The purpose of this series is to present deciduosis (the formation of extrauterine decidua) as one of the differential diagnoses of a malignant tumor during pregnancy.

METHODS

Two cases are described in which pregnant patients had a pelvic tumor. The lesions, which were diagnosed in the early second trimester, consisted of complex masses with an extensive blood supply and had a sonographic appearance of a malignant tumor. The high suspicion for malignancy necessitated surgical intervention.

RESULTS

During surgery, the lesions were observed to be of an ovarian origin with papillary excrescences covering their exterior. The lesions were excised and sent for histologic examination. The results showed a markedly decidualized endometriotic cyst in both cases.

CONCLUSIONS

This phenomenon is a diagnostic challenge and should be considered in the differential diagnosis of a malignant mass during pregnancy.

Variables associated with successful vaginal birth after one cesarean section: a proposed vaginal birth after cesarean section score

The objective of this study was to define the variables associated with vaginal birth after cesarean section (VBAC) and to develop a scoring system for the prediction of successful VBAC. We searched our computerized database for parturients with a history of one low-transverse cesarean section (CS) who were delivered during the year 2000. Variables were categorized according to the time period in which they were obtained: (1) first prenatal visit, (2) at the onset of labor, and (3) during labor. Univariate and multiple stepwise logistic regression models were fitted to calculate odds ratios (ORs) and 95% confidence intervals (CIs). Of the 475 parturients with a history of one previous CS, 136 underwent elective CS and 339 underwent a trial of VBAC, of whom 82% were successful. Of the variables that can be obtained at the onset of labor, five were significantly associated with successful VBAC: abnormal presentation as the indication for the primary CS (OR, 7.4; 95% CI 2.8 to 19.2), a previous VBAC (OR, 7.2; 95% CI, 2.1 to 24.8), cervical dilation (OR, 2.5; 95% CI, 1.3 to 4.9), gestational age < or = 41 weeks (OR, 2.8; 95% CI, 1.1 to 7.1), and lower gestational age at the primary CS (OR, 1.2; 95% CI, 1.02 to 1.4). In the proposed VBAC score, each of the four most significant variables was assigned a score ranging between 0 and 3 based on the probability for VBAC. A score < or = 2 was associated with a success rate of 42%, a score between 3 and 6 was associated with a rate of 81%, and a score between 7 and 10 was associated with a 98% successful VBAC rate (p < 0001). The proposed VBAC score may help obstetricians when counseling their patients regarding the individual likelihood of a successful VBAC.

Second trimester abortion by laminaria followed by vaginal misoprostol or intrauterine prostaglandin F2alpha: a randomized trial

Intra-amniotic injection, as well as intravaginal application of prostaglandins, have been used to terminate second trimester pregnancies. There is as yet no consensus as to the most efficient protocol of such late abortions. Our goal was to compare the efficacy of intra-amniotic injection of prostaglandin F2 alpha (PGF2alpha) and intravaginal application of misoprostol in terminating second trimester pregnancies after pretreatment with intracervical laminaria. Women with live fetuses and requesting second trimester abortions were randomized into two groups. Eighteen hours following the insertion of intracervical laminaria, women were treated with either intra-amniotic injection of 40 mg PGF2alpha, or 12 hourly doses (to a maximum of 4 doses) of 200 mcg misoprostol. Fifty women were randomly assigned to each group. Failure to abort within 24 h of initiation of treatment occurred in 6 patients (12%) in the misoprostol group and 14 (28%) of the PGF2alpha group (p = 0.04). Mean time of induction of pharmacologic treatment to abortion was 13.6 h in the misoprostol group and 10.7 h in the PGF2alpha group (p = 0.03). The mean number of analgesic injections given were 0.8 in the misoprostol group and 1.6 in the PGF2alpha group (p = 0.0001). Only the method of abortion was predictive of abortion success and not other variables such as patient age, gestational age, gravidity, or parity. Following intracervical laminaria, vaginal misoprostol has been found to be more effective and less painful, compared with intra-amniotic PGF2alpha, for the termination of second trimester pregnancies with live fetuses.

Ultrasound evaluation of the fetal skull base throughout pregnancy

OBJECTIVE

To construct nomograms for cranial base parameters of normal fetuses.

STUDY DESIGN

A cross-sectional study of 386 normal singleton fetuses at 14-40 weeks' gestation. Measurements of the length and width of the sphenoid bone anteriorly and the otic cartilage posteriorly and of the angles between the ridges were obtained.

RESULTS

Nomograms of the length and width of sphenoid ridge and otic cartilage, and of the angles in the cranial fossae are presented. A linear growth function was observed between cranial base measurements (sphenoid ridge length, otic cartilage length, cranial base angles) and gestational age, femur length and biparietal diameter.

CONCLUSION

Measurements of the length of cranial base ridges and the angles between them can be obtained easily in the second and third trimesters and might prove useful in the evaluation of pregnancies at high risk for associated fetal abnormalities.

Obstetricians' opinions regarding patient choice in cesarean delivery

OBJECTIVE

To survey the opinions of Israeli obstetricians regarding their position on patient choice cesarean delivery.

METHODS

Short anonymous questionnaires were sent by mail. The questionnaire included basic demographic data followed by three short case presentations of patients requesting cesarean delivery without a medical indication; the respondents were asked if they would consent to the patients' request. Respondents were then asked about their personal preferences on the mode of delivery, their attitude towards women's right to choose cesarean delivery, and whether obstetricians should inform their patients of this right.

RESULTS

Of the 650 questionnaires sent, 257 were returned. Most of the respondents were specialists, aged 35 years or older, and worked in hospitals. Seventy-five percent were male, and 27% had a teaching academic degree. The consent rate for patient choice cesarean delivery in the three case presentations ranged from 40% to 79%. Only 9% of the respondents said they would prefer cesarean delivery for themselves (if female) or for their partners. Forty-five percent supported women's right to choose cesarean delivery, and half of them stated that obstetricians should inform their patients of this right.

CONCLUSION

Although the vast majority (91%) of the Israeli respondents personally prefer vaginal delivery, almost half of them support women's autonomy to choose cesarean delivery. Consequently, approximately 50% of the respondents were willing to perform cesarean delivery on request because of their support of women's autonomy, despite the fact that they believe that vaginal delivery is a better option.

A new guidance system for freehand, obstetric ultrasound-guided procedures

OBJECTIVE

To assess the performance of the UltraGuide 1000 system, and to compare ultrasound-guided freehand mid-trimester amniocentesis with and without the new guidance system.

METHODS

One hundred and sixty-nine women referred for mid-trimester genetic amniocentesis were divided into two groups: a control group of 99 women who underwent the procedure by the freehand technique with scored needles and 70 patients who had the procedure carried out with the aid of a guidance system (UltraGuide 1000) with non-scored needles. The procedures were compared for duration, number of punctures and repositionings of the needle, the visibility of the needle during the puncture and the number of bloody taps.

RESULTS

The study group had significantly lower rates of reinsertion (none vs. 7.1%), repositioning (7.1% vs. 17.7%), bloody taps (none vs. 6.1%), touching the fetus (5.7% vs. 22.2%) and prolonged duration of the procedure (4.3% vs. 14.4%) compared with the control group. There was one fetal loss in the control group. Non-visibility of the needle before reaching the amniotic sac occurred in 18.6% of cases in the study group and in 38.4% of cases in the control group.

CONCLUSIONS

The new guidance system combines the benefits of an attached guide with the flexibility of the 'freehand' technique. Use of the new guidance system for mid-trimester genetic amniocentesis increases needle visibility and lowers the incidence of common complications.

Sonographic appearance of appendiceal mucocele

We present a case of the diagnosis of an appendiceal mucocele in a 23-year-old woman. The unusual preoperative sonographic appearance of the lesion is described and its clinical significance and differential diagnosis are discussed.

Early second-trimester low umbilical coiling index predicts small-for-gestational-age fetuses

OBJECTIVE

To evaluate the role of the early second-trimester Doppler velocimetric studies of the umbilical coiling index and umbilical cord cross-sectional area as tests for the prediction of small-for-gestational age infants.

METHODS

Doppler blood flow studies in 147 singleton pregnancies at risk for delivery of a small-for-gestational-age neonate were performed at 15 +/- 1 (SD) weeks' gestation from the uterine artery, umbilical artery, middle cerebral artery, inferior vena cava, and ductus venosus. Pulsatility index values were calculated for the arteries, and preload index values and systolic-atrial contraction ratios were calculated for the veins. The sonographic cross-sectional area of the umbilical cord was measured in a plane adjacent to the insertion into the fetal abdomen. The umbilical coiling index was calculated by using sonographic longitudinal views of cord vessels from several segments antenatally and by dividing the total number of helices by cord length (centimeters) postnatally. Small-for-gestational-age neonates were identified when the birth weight was below the 10th percentile for gestational age.

RESULTS

Among 147 pregnancies studied, 124 fulfilled the study criteria. Thirty-nine of the neonates were small for gestational age at birth (31.5%). The mean +/- SD gestational age at delivery of the appropriate-for-gestational-age neonates was 39.7 +/- 1.28 weeks, and that of the small-for-gestational-age neonates was 36.4 +/- 2.9 weeks (range, 28-40 weeks). The best single predictor of a small-for-gestational-age infant was the coiling index, with sensitivity of 79%, specificity of 86%, a positive predictive value of 72%, and a negative predictive value of 90%.

CONCLUSIONS

The umbilical coiling index measured in the second trimester is useful in predicting the birth of a small-for-gestational-age infant and may serve as a marker for subsequent growth restriction.

Cross talk between beta(1) and alpha(V) integrins: beta(1) affects beta(3) mRNA stability

There is increasing evidence that a fine-tuned integrin cross talk can generate a high degree of specificity in cell adhesion, suggesting that spatially and temporally coordinated expression and activation of integrins are more important for regulated cell adhesive functions than the intrinsic specificity of individual receptors. However, little is known concerning the molecular mechanisms of integrin cross talk. With the use of beta(1)-null GD25 cells ectopically expressing the beta(1)A integrin subunit, we provide evidence for the existence of a cross talk between beta(1) and alpha(V) integrins that affects the ratio of alpha(V)beta(3) and alpha(V)beta(5) integrin cell surface levels. In particular, we demonstrate that a down-regulation of alpha(V)beta(3) and an up-regulation of alpha(V)beta(5) occur as a consequence of beta(1)A expression. Moreover, with the use of GD25 cells expressing the integrin isoforms beta(1)B and beta(1)D, as well as two beta(1) cytoplasmic domain deletion mutants lacking either the entire cytoplasmic domain (beta(1)TR) or only its "variable" region (beta(1)COM), we show that the effects of beta(1) over alpha(V) integrins take place irrespective of the type of beta(1) isoform, but require the presence of the "common" region of the beta(1) cytoplasmic domain. In an attempt to establish the regulatory mechanism(s) whereby beta(1) integrins exert their trans-acting functions, we have found that the down-regulation of alpha(V)beta(3) is due to a decreased beta(3) subunit mRNA stability, whereas the up-regulation of alpha(V)beta(5) is mainly due to translational or posttranslational events. These findings provide the first evidence for an integrin cross talk based on the regulation of mRNA stability.

Cardiac function in fetuses with intracardiac echogenic foci

OBJECTIVE

To evaluate cardiac dimensions and function in euploid fetuses with intracardiac echogenic foci.

STUDY DESIGN

Forty-eight fetuses with a single cardiac echogenic focus situated in the left ventricle had echocardiography performed at 22-24 weeks of gestation. Fifty normal fetuses at 22-24 weeks' gestation served as controls. Two-dimensional and M-mode directed fetal echocardiography were used to exclude cardiac anomalies and measure right and left ventricular free walls and interventricular septal thickness and ventricular systolic and diastolic dimensions. Cardiac size was expressed as a ratio of ventricular wall thickness/biparietal diameter, and cardiac function was expressed as ventricular shortening fraction. Doppler fetal echocardiography measurements included pulmonary and aortic maximum systolic velocities and time to peak velocities as indices of ventricular systolic function, and the ratio between early ventricular filling (E-wave) and active atrial filling (A-wave) peak velocities at the level of the atrioventricular valves as an index of ventricular diastolic function.

RESULTS

Early ventricular filling/active atrial filling peak velocity ratios were significantly lower in fetuses with intracardiac echogenic foci than in control fetuses. In the mitral valve the ratio was 0.37 +/- 0.14 (0.039) (mean +/- SD (95% confidence interval for difference between the means)) vs. 0.59 +/- 0.19 (0.052) and in the tricuspid valve it was 0.42 +/- 0.16 (0.045) vs. 0.62 +/- 0.21 (0.058). No significant differences were found in cardiac dimensions, ventricular shortening fraction and Doppler systolic indices.

CONCLUSION

Euploid fetuses with intracardiac echogenic foci show low E/A ratio values in midtrimester echocardiography. This finding might indicate cardiac diastolic dysfunction.

Fetal biometry: clinical, pathological, and technical considerations

Sonographic measurements of fetal ultrasound parameters are the basis for accurate determination of gestational age and detection of fetal growth abnormalities. Selection of the most useful single biometric parameter depends on the timing and purpose of measurement and is influenced by specific limitations. CRL (crown-rump length) is the best parameter for early dating of pregnancy. Biparietal diameter (BPD) maintains the closest correlation with gestational age in the second trimester. In cases of variation in the shape of the skull, head circumference is an effective alternative. Abdominal circumference is the most useful dimension to evaluate fetal growth, and femur length is the best parameter in the evaluation of skeletal dysplasia. Use of multiple predictors improves the accuracy of estimates. An individual approach to each pregnancy is recommended for fetal growth assessment. The various epidemiological factors involved in fetal growth should be considered and specific charts for different communities should be used when possible. The methods of fetal weight estimation with their limitations and potential errors are presented. Clinical application of fetal biometry in abnormal growth is discussed in cases of small- and large-for-gestational-age fetuses, chromosomal aberrations, and skeletal dysplasias.

Association between epidural analgesia and intrapartum fever

The objective of this paper is to determine whether or not epidural analgesia is an independent risk factor for intrapartum fever. Maternal temperature was measured every 4 h during labor to 1004 consecutive women in term labor. Women with fever or on antibiotics were excluded. Epidural analgesia was administered upon patients' request. Of the 406 (40%) women who received epidural analgesia, 11.8% (n = 48) developed a fever > or = 37.8 degrees C during labor compared with only 0.2% (n = 1) of women not receiving epidural analgesia. Women who received epidural analgesia were more likely to have one or more risk factors for intrapartum infection. Their labor and ruptured membranes were longer, they were more likely to have internal monitoring and have more vaginal examinations. Compared with women who received epidural analgesia and did not develop intrapartum fever, women that did develop fever had longer epidurals and more risk factors for infection. However, in a logistic regression analysis with fever as dependent variable, only the duration of epidural was significantly associated with the occurrence of fever. The rate of fever increased with longer labors, from 5% with labor < 3 h to 28% with labor > 6 h. In 90% of women the fever resolved within a few hours after delivery. Sepsis evaluation was negative in all of the newborns to mother who had intrapartum fever. Our data support a noninfectious etiology for intrapartum fever in the vast majority of our patients. However, infection must be ruled out before a decision is made to withhold antibiotic therapy.

Endometrium-to-myometrium relative echogenicity coefficient. A new sonographic approach for the quantitative assessment of endometrial echogenicity

A computer program was developed to assess the endometrial echogenicity relative to the myometrial one, based on the gray-level processing of the midsagittal uterine image. The endometrial region of interest was specified within the upper part of the uterine cavity. The adjacent area of the myometrium was used to determine the reference brightness. The endometrial region of interest was analyzed along the anteroposterior uterine axis, as a set of thin strips directed parallelly to the midcavitary line. The endometrial/myometrial relative echogenicity coefficient (E/M REC) was computed for each strip and displayed graphically as a function of the distance from the midcavitary line. The area under the E/M REC curve within the limits of the total endometrial width was defined as total area (TA) and was used as a measure of the endometrial echogenicity. This parameter was assessed in 9 patients during their normal ovulatory cycles and in 29 IVF-treated patients with mechanical infertility. TA has a significant linear increase during the days of the ovulatory cycles. TA was found in high correlation with log(estradiol). TA can be used reliably for sonographic endometrial dating in ovulatory cycles.

The influence of maternal exercise on placental blood flow measured by Simultaneous Multigate Spectral Doppler Imaging (SM-SDI)

OBJECTIVE

To evaluate the effect of maternal isometric exercise on the placental blood flow as reflected by the velocimetric indices PI and RI derived from placental arteries.

SUBJECTS

Thirty-four healthy women with normal singleton pregnancies between 22 and 35 weeks of gestation.

METHODS

All subjects underwent an isometric handgrip exercise test. Maternal blood pressure and heart rate together with placental PI and RI were measured at rest, during the exercise and in the post-exercise recovery phase. All Doppler measurements were obtained using the Simultaneous Multigate Spectral Doppler Imaging (SM-SDI) technique, a new ultrasound modality that enables a Doppler study of multiple locations to take place within a very short time.

RESULTS

There was a significant increase in the mean values of the maternal blood pressure and heart rate during the exercise and a significant decline in the recovery phase. There was no significant change in the mean values of the Doppler indices throughout the examination.

CONCLUSION

Isometric handgrip exercise test during pregnancy does not affect the impedance of the placental circulation.

Intrapartum drainage of fetal pleural effusion

Our objective was to describe our experience with intrapartum thoracocentesis in fetuses with severe bilateral pleural effusion. We describe the outcome of four consecutive cases of fetal pleural effusion due to chylothorax that were managed by intrapartum thoracocentesis. These fetuses were not candidates for pleuro-amniotic shunting either because of the need for prompt delivery (three fetuses) or because of advanced gestational age (one fetus). Thoracocentesis was performed in the operating theatre under ultrasound guidance prior to Caesarean delivery. Gestational age at the time of diagnosis and thoracocentesis ranged between 26-34 weeks and 31-34 weeks respectively. Bilateral thoracocentesis was performed in two fetuses and unilateral in the remaining two fetuses. All four infants were born in a relatively good condition; however, all eventually required intubation, ventilation and chest tubes. Chest tubes were introduced between 2 h and 5 days after delivery in three infants, and immediately after birth in one infant who was hydropic. Two infants survived and are developing normally. One infant died from sepsis following successful pleurodesis and one from aspiration on day 51. Our conclusions are that intrapartum thoracocentesis seems to be a relatively simple procedure, that allows newborns with pleural effusion, to breathe spontaneously or be more easily ventilated. This in turn, reduces the need to introduce chest tubes in an emergency situation.

Assessment of endometrial receptivity for gestation in patients undergoing in vitro fertilization, using endometrial thickness and the endometrium-myometrium relative echogenicity coefficient

OBJECTIVE

To evaluate the outcome of in vitro fertilization (IVF) treatment in relation to the sonographic parameters of the endometrium.

DESIGN AND METHODS

Seventy-five patients with no uterine pathology (age 31.1 +/- 5.4 years) treated in our IVF clinic for various indications were assessed during 75 cycles in which good-quality (grades 1 and 2) embryos were transferred. Controlled ovarian stimulation was achieved by the long protocol (gonadotropin releasing hormone agonist and gonadotropins). The bilayered endometrial thickness (BET), estradiol, luteinizing hormone and progesterone serum levels were measured in 272 tests. A special computer program was used to measure endometrial echogenicity relative to myometrial echogenicity. The gray-level data were analyzed on the basis of the midsagittal sonographic uterine image. Endometrium-myometrium relative echogenicity coefficient (E/M REC) values were computed and displayed graphically along the anteroposterior axis of the endometrial layers in the upper part of the uterine cavity. The area under the E/M REC curve within the BET limits was defined as the relative echogenicity area (REA) and was used as a measure of endometrial echogenicity. Each cycle was sampled in six time segments representing desensitization, follicular and luteal phases. Assigning the day of ovum pick-up as day 0, the time segments of each cycle were: first, day -20 to day -11; second, day -10 to day -6; third, day -5 to day -2; fourth, day 0; fifth, day +7 to day +14; sixth, day +15 to day +21.

RESULTS

A total of 276 embryos were transferred (3.68 +/- 1.01 per cycle), of which 223 were of good quality (2.97 +/- 1.51 per cycle). An intrauterine pregnancy was diagnosed in 29 patients. All patients in this study had a BET of > 5 mm in the third and the fourth time segments. There was no significant difference in BET and REA between pregnant and non-pregnant patients tested in the first to the fifth time segments of the IVF cycles. Both BET and REA measured in the sixth time segment were significantly higher in pregnant compared to non-pregnant patients.

CONCLUSIONS

Our results suggest that the proposed sonographic assessment of the endometrium shows no benefit in characterization of uterine receptivity in IVF patients with a reactive endometrium. High BET and REA values can indicate pregnancy during the sixth time segment, when the decidualization of the endometrium is well established.

Fetal cardiac measurements derived by transvaginal and transabdominal cross-sectional echocardiography from 14 weeks of gestation to term

OBJECTIVE

Most of the routine ultrasound screening in our institution consists of early transvaginal examinations at 14-17 weeks. Complete fetal echocardiography is performed in every case. However, normal values for most fetal cardiac structures at this stage of gestation are not available. Our aim was to construct normal ranges for fetal cardiac structures, derived from cross-sectional echocardiography, at 14-40 weeks of gestation.

DESIGN

A prospective study was performed. The study group consisted of 637 pregnant women referred for a routine sonographic examination. Women with abnormal prenatal or postnatal outcome were not included in the study. Transvaginal examinations were used for 14-17 weeks of gestation. More advanced pregnancies were examined transabdominally.

RESULTS

We constructed normal ranges for the left and right end-diastolic transverse ventricular diameters (n = 637), left/right ventricular ratio (n = 637), aortic root diameter (n = 637), pulmonary artery diameter (n = 637), aortic/pulmonary ratio (n = 490), left and right transverse atrial diameters (n = 201) and left/right atrial ratio (n = 201).

CONCLUSIONS

The results provide the examiner with normal ranges for fetal cardiac structures for the early transvaginal examination. The continuity of all curves from 14 to 40 weeks of gestation allows follow-up of any specific fetus to term.

Prospective randomized comparison between an open and closed vaginal cuff in abdominal hysterectomy

OBJECTIVE

To compare an operative and postoperative course of open vaginal cuff hysterectomy and closed vaginal cuff hysterectomy, and to correlate the length of stay, febrile morbidity and the incidence of pelvic fluid collections to the type of surgery.

PARTICIPANTS

One-hundred women scheduled for hysterectomy were prospectively randomized into two groups that underwent either a closed or an open vaginal cuff technique.

RESULTS

The open vaginal cuff technique took on average 19% more time than the closed vaginal cuff operation (P < 0.05, t-test). The incidence and size of pelvic fluid collections was significantly higher after the closed vaginal cuff hysterectomy than after the open technique (P < 0.01, t-test). However, the postoperative length of stay, febrile morbidity and the rate of complications were similar.

CONCLUSIONS

Both techniques of hysterectomy produced a similar postoperative course despite the fact that the closed vaginal cuff technique resulted in a higher incidence of pelvic fluid collections. Therefore considering a shorter operation time for the closed vaginal cuff hysterectomy, this technique seems slightly preferable.

Myometrial thickness in pregnancy: longitudinal sonographic study

The purpose of this study was to evaluate in vivo the changes in myometrial thickness throughout pregnancy. Myometrial thickness was measured in 25 singleton uncomplicated pregnancies. Ultrasonographic sagittal and transverse sections were used to measure uterine wall thickness from the low anterior wall (lower segment) and the anterior, posterior, right, and left walls of the upper segment and from the fundus. In each case four measurements were made in the second and third trimesters. Myometrial thickness of the upper uterine segment remains fairly constant in the first and second trimesters of pregnancy, whereas a significant linear trend was found between a decreasing thickness of the lower uterine segment and advancing gestational age. Myometrial thickness is significantly increased behind the placental insertion site as compared to other portions of the uterine wall. These data may serve as baseline reference values for further studies in the antepartum fetal surveillance of high-risk pregnancies.

Prediction of successful induction of labor: comparison of transvaginal ultrasonography and the Bishop score

OBJECTIVE

To determine whether transvaginal ultrasonography of the cervix before induction of labor is a better predictor of successful induction than the Bishop score.

STUDY DESIGN

Eighty-six consecutive patients scheduled for induction of labor underwent digital cervical examination followed by transvaginal ultrasonography to measure cervical length and to determine the presence of wedging. Patients were induced with either oxytocin or intracervical prostaglandin E2 gel followed by oxytocin when required. The agent for induction was selected on the basis of the digital examination. The primary outcome criteria were successful induction and the duration of labor.

RESULTS

Successful induction and the duration of labor were significantly associated with the Bishop score and cervical length. Cervical wedging was associated only with successful induction. However, in a logistic regression model that included these parameters as independent variables, only the Bishop score and parity were significantly correlated with successful induction and the duration of labor.

CONCLUSIONS

Transvaginal ultrasonographic evaluation of the cervix before induction of labor does not improve the prediction of cervical inducibility obtained by the Bishop score.

The instantaneous measurement of multiple Doppler spectra in the investigation of ovarian masses

The use of Doppler indices of tumor vascularity as markers for malignancy has been a subject of debate, with inconsistencies in specificity and sensitivity as well as in the diagnostic cut-off values. Part of the discrepancy might be explained by the limited number of vessels selected within the tumor for Doppler evaluation. A typical sample of three or four vessels may not be sufficiently large for correct representation of the vasculature of the tumor, which may contain many vessels. The existing conventional Doppler (color and spectral) techniques clearly have limitations. We present here a novel Doppler modality, namely two-dimensional spectral Doppler imaging (SDI), which allows the acquisition of many Doppler spectra within a few seconds. The operator selects a region of interest within a color Doppler image. The Doppler sequence is initiated and the entire selected region is automatically scanned for about 20 s until all spectral Doppler data have been acquired and processed. The system computer generates a color-coded map of the desired Doppler indices overlaid on the gray-scale image. The system also displays a cumulative histogram or a table of the requested Doppler index from all the sections in the tissue. The whole process is automatically performed by the system computer, without any need for operator intervention. The system provides the examiner with a 'fishing net' for Doppler indices, instead of the 'fishing hook' used in current techniques.

Fetal pyelectasis in consecutive pregnancies: a possible genetic predisposition

Mild fetal pyelectasis is a relatively common finding. The objective of this study was to assess its recurrence rate in subsequent pregnancies. The study comprised 420 women with two consecutive normal uncomplicated pregnancies screened at 15-24 weeks' gestation by ultrasound. Pyelectasis was defined as a fetal pelvis of 4 mm or more in its anterior-posterior dimensions. Of 64 fetuses with pyelectasis, 43 (67%) had a recurrence of this finding in their subsequent pregnancy. Compared with normal fetuses, those with pyelectasis had a relative risk of 6.1 to have a recurrence of this finding in their next pregnancy (95% confidence interval, 4.3-7.5, p < 0.001). These results suggest a predisposition for pyelectusis that may be influenced by genetic and/or environmental factors. More data are needed before an accurate adjustment based on previous results can be made.

Accurate diagnosis of postabortal placental remnant by sonohysterography and color Doppler sonographic studies

The decision whether to perform uterine curettage for postabortal bleeding depends on the ability to demonstrate placental remnants in the uterine cavity. However, diagnosis of postabortal trophoblastic residua by conventional ultrasonography may be inconclusive. We report our experience with the use of combined sonohysterography and color Doppler to demonstrate a placental polyp after early pregnancy termination.

Sonographic evaluation of the uterus in postmenopausal women receiving tamoxifen: characterization of mid-uterine abnormalities

BACKGROUND

Tamoxifen is known to exert agonist estrogenic effects on the uterus. Its use in postmenopausal women has also been associated with various endometrial and uterine abnormalities that can be detected by endovaginal sonography.

OBJECTIVE

To study postmenopausal patients receiving tamoxifen who were referred for evaluation following the detection of abnormal uterine findings by endovaginal sonography.

METHODS

Fifty-two women treated with tamoxifen for breast cancer who were found to have an abnormal uterine sonogram constituted the study population. Uterine sonograms were reviewed and clinical and sonographic data were correlated with the results of the histologic examinations.

RESULTS

Forty-five women demonstrated a thickened mid-uterine structure. Of these, in thirty-nine patients (87%) either no tissue of scant fragments of normal endometrium were obtained on curettage, and six women (13%) had endometrial hyperplasia. Seven women had fluid loculation lined by thin endometrium. Their subsequent histologic examination was normal. The sonograms of the women who demonstrated an appearance of a thickened endometrium but no neoplasia, characteristically demonstrated hyperechogenic cystic area with no midline echo.

CONCLUSIONS

Among 52 postmenopausal patients receiving tamoxifen presented with an abnormal uterine sonogram, 39 (75%) women were found to have a thick mid-uterine structure resembling a thickened endometrium without histologic evidence of neoplasia. This phenomenon can be characterized by typical sonographic features, and may be differentiated from other uterine abnormalities.

The effect of maternal prostaglandin administration on fetal ductus venosus blood flow velocity

Our objective was to investigate whether maternal administration of prostaglandins PGE2 and PGF2(alpha) is associated with changes in fetal ductus venosus flow velocity waveforms. Second-trimester termination of pregnancy was induced in 11 women (group A) by intra-amniotic instillation of 40 mg PGF2(alpha). In group B, 19 patients received 0.5 mg PGE2 intracervically for preinduction cervical ripening. Doppler flow velocity waveforms were recorded from the fetal ductus venosus immediately before and 40-60 min after prostaglandin administration. The paired t-test was used for statistical analysis of the ductus venosus index (DVI). The mean DVI decreased after PGF2(alpha) administration from 0.62 +/- 0.12 to 0.52 +/- 0.13 (p < 0.01); and from 0.62 +/- 0.10 to 0.58 +/- 0.12 (p < 0.05) after PGE2 administration. Atrial peak velocities were significantly increased after the procedures. No significant changes were found for systolic peak velocity values. The data indicate that major changes in ductus venosus hemodynamics are induced by PGF2(alpha) and PGE2.

The antenatal diagnosis of fetal atrial septal aneurysm

Fetal atrial septal aneurysm (ASA) is uncommon and little is known regarding its prevalence and clinical significance. In this report we describe 2 cases of fetal ASA diagnosed by ultrasonography. They were referred for examination because of fetal tachyarrhythmia in 1 case, and polyhydramnios in the other. The first case had a normal outcome, while the other was associated with other congenital heart malformations. The literature as regards the diagnosis, prevalence, pathology, and clinical implications of ASA is discussed.

Sonographic estimation of umbilical coiling index and correlation with Doppler flow characteristics

OBJECTIVE

To quantitate umbilical vascular coiling antenatally, and to correlate the coiling index with Doppler flow characteristics in umbilical vessels.

METHODS

We studied 45 normal term fetuses within 24 hours before delivery. The umbilical coiling index was calculated using sonographic longitudinal views of cord vessels from several segments antenatally, and by dividing the total number of helices by the cord length (in centimeters) postnatally. Doppler flow velocities were obtained from umbilical arteries and vein in each cord. Flow characteristics were correlated with the umbilical coiling index.

RESULTS

The mean (+/- standard deviation) umbilical coiling index was 0.44 +/- 0.11 in the antepartum period and 0.28 +/- 0.08 after birth. Regression analysis showed a significant linear trend (r = 0.71, P < .001). The correlations between sonographic coiling index and umbilical arterial Doppler flow characteristics (mean velocity, pulsatility index, resistance index, and systolic-diastolic ratio) were not significant. The sonographic coiling index was related to time-averaged velocity and flow in the umbilical vein. A good correlation was found between umbilical vein flow and the coiling index, with a significant linear trend (r = 0.59, P < .001).

CONCLUSION

An intrauterine umbilical coiling index can be determined by ultrasound and correlates well with the actual index at birth. The sonographic umbilical coiling index is related to Doppler flow characteristics in the umbilical vein.