Three-dimensional volume sonographic study of fetal anatomy: intraobserver reproducibility and effect of examiner experience.

OBJECTIVE: The purpose of this study was to evaluate the accuracy of 3-dimensional (3D) sonography in assessing fetal anatomy and to determine the intraobserver reproducibility and the effect of examiner experience. METHODS: Three-dimensional volumes of the head, face, thorax, and abdomen were obtained for 40 fetuses. The volume data sets obtained were explored offline with multiplanar navigation and tomographic ultrasound imaging on a personal computer. Each case was examined twice by the same observer at least 3 months apart. The percentage for identification of fetal anatomic structures, 2-dimensional (2D) and 3D measurements, and the time spent on 2D and 3D examinations were calculated and compared. RESULTS: Ninety-two percent of fetal anatomic structures were identified with multiplanar navigation and tomographic ultrasound imaging. The genitals, the entry of the vena cava, and the ears were visualized in less than 70% of cases. Tomographic ultrasound imaging allowed viewing of 14 structures not seen in the multiplanar study. Intraobserver agreement for anatomic examinations was good (kappa = 0.78). Intraobserver agreement for fetal measurements showed differences between both examinations that approached 0 and intraclass correlation indices close to 0.9. The mean 2D scanning time +/- SD was 10.11 +/- 2.5 minutes, and the acquisition time for the 3D volumes was 1.54 +/- 0.35 minutes. The total time for the second 3D study was 7.23 +/- 1.17 minutes, significantly shorter than the 9.96 +/- 1.53 minutes spent on the first study (P < .001). CONCLUSIONS: Three-dimensional volumes are highly effective for complete fetal anatomic surveys. They show excellent intraobserver reproducibility and take less time to study as the examiner's experience increases.     

Does Sonographic Determination of Placental Location Predict Fetal Birth Weight in Diamniotic‐Dichorionic Twins?

OBJECTIVE: The purpose of this study was to determine the association between placental location in diamniotic-dichorionic twins as determined at the time of anatomic survey and birth weight. METHODS: We retrospectively identified all diamniotic-dichorionic twins in our Maternal-Fetal Medicine sonography database between 2000 and 2005 who had an anatomic survey, went on to be delivered at our hospital, and had records available for review (n = 304). Placental location for each twin was determined at the time of anatomic survey and grouped into both anterior or both posterior versus separate anterior and posterior. Maternal and fetal characteristics were collected from chart review. Placental pathologic findings were available for 249 (83%) patients. Outcomes analyzed were percent discordance, small size for gestational age of twin A or B, and difference in birth weight as a continuous variable. Multivariable logistic regression using stepwise backward elimination was used to adjust for potential confounders. RESULTS: There was no difference in discordance of 20% or greater or incidence of small size for gestational age when both placentas were both anterior and both posterior compared with separate anterior and posterior: adjusted odds ratio (AdjOR), 1.38 (95% confidence interval [CI], 0.64-2.95); and AdjOR, 1.29 (95% CI, 0.57-2.89). The actual birth weight difference (A - B) was not affected by placental location (P = .36). Opposite sex fetuses and nulliparity were significantly associated with birth weight discordance: AdjOR, 2.68 (95% CI, 1.39-5.17); and AdjOR, 0.34 (95% CI, 0.28-0.94). CONCLUSIONS: We did not find a correlation between birth weight and placental location in our cohort analysis. The presence of sex-discordant twins was associated with birth weight discordance of 20% or greater, whereas nulliparity was protective.     

羊水量异常的超声诊断与胎儿畸形的关系

目的 探讨羊水量异常与胎儿畸形的关系.方法 回顾分析2004年3月至2006年11月在本院进行二维及三维超声检查34 900例20周以上的胎儿,其检出羊水量异常160例,并研究分析羊水量多少与胎儿畸形的关系.结果 160例羊水量异常中,羊水过多100例,羊水过少60例,二者畸形的发生率分别为37%、31.6%.结论 超声是诊断羊水量异常的首选方法,而且还能发现胎儿畸形,进一步证明羊水量异常与胎儿畸形的发生密切相关.     

Measurement of fetal urine production by three-dimensional ultrasonography in normal pregnancy.

OBJECTIVES: Measurement of fetal urine production may provide a means of evaluating amniotic fluid volume, which is difficult to measure directly, and predicting fetal hypoxia. Although there have been some reports on fetal urine production, most of these have used two-dimensional (2D) ultrasonography to measure bladder volume. Three-dimensional (3D) ultrasonography is, however, known to be superior to 2D ultrasonography in some organ volume measurements. Thus, we undertook this study to measure bladder volumes using 3D ultrasonography and to establish a nomogram of fetal urine production rate (UPR) according to gestational age (GA). METHODS: One hundred and fifty-four women with a normal singleton pregnancy at 24 to 40 weeks' gestation were enrolled in this cross-sectional study. The women had no medical or obstetric complications affecting amniotic fluid volume. Fetal bladder volume was measured using 3D ultrasound imaging and Virtual Organ Computer-aided AnaLysis (VOCAL) with a rotational angle of 30 degrees and manual surface tracing technique. Bladder volume was measured two or three times within a 5-10-min interval and fetal UPR was calculated from serial measurements. When measurements were performed more than twice, we used the mean rate of calculated UPRs. UPR was then plotted against GA to establish the nomogram. RESULTS: Fetal UPR increased with GA from a median value of 7.3 mL/h at 24 weeks' gestation to 71.4 mL/h at term, and could be calculated from GA using the formula: Ln(UPR) = - 6.29582 + (0.43924 x GA) + (0.000432 x GA2), r2 = 0.63, P = 0.0046. Growth percentiles of UPR according to age are presented. CONCLUSIONS: Fetal UPR can be easily measured by 3D ultrasound assessment of bladder volume. This modality may be a promising alternative to conventional methods of amniotic fluid volume measurement such as amniotic fluid index and single deepest pocket, and might be an alternative option for predicting fetal hypoxia.     

Real-time 3-dimensional fetal echocardiography with an instantaneous volume-rendered display: early description and pictorial essay.

OBJECTIVE: Random fetal motion, rapid fetal heart rates, and cumbersome processing algorithms have limited reconstructive approaches to 3-dimensional fetal cardiac imaging. Given the recent development of real-time, instantaneous volume-rendered sonographic displays of volume data, we sought to apply this technology to fetal cardiac imaging. METHODS: We obtained 1 to 6 volume data sets on each of 30 fetal hearts referred for formal fetal echocardiography. Each volume data set was acquired over 2 to 8 seconds and stored on the system's hard drive. Rendered images were subsequently processed to optimize translucency, smoothing, and orientation and cropped to reveal "surgeon's eye views" of clinically relevant anatomic structures. Qualitative comparison was made with conventional fetal echocardiography for each subject. RESULTS: Volume-rendered displays identified all major abnormalities but failed to identify small ventricular septal defects in 2 patients. Important planes and views not visualized during the actual scans were generated with minimal processing of rendered image displays. Volume-rendered displays tended to have slightly inferior image quality compared with conventional 2-dimensional images. CONCLUSIONS: Real-time 3-dimensional echocardiography with instantaneous volume-rendered displays of the fetal heart represents a new approach to fetal cardiac imaging with tremendous clinical potential.     

Satisfactory Visualization Rates of Standard Cardiac Views at 18 to 22 Weeks' Gestation Using Spatiotemporal Image Correlation

Objective. The purpose of this study was to determine the frequency with which 3 standard screening views of the fetal heart (4-chamber, left ventricular outflow tract [LVOT], and right ventricular outflow tract [RVOT]) can be obtained satisfactorily with the spatiotemporal image correlation (STIC) technique. Methods. A prospective study of 111 patients undergoing anatomic surveys at 18 to 22 weeks was performed. Two ultrasound machines with fetal cardiac settings were used. The best volume set that could be obtained from each patient during a 45-minute examination was graded by 2 sonologists with regard to whether the 4-chamber, LVOT, and RVOT images were satisfactory for screening. Results. All 3 views were judged satisfactory for screening in most patients: 1 sonologist graded the views as satisfactory in 70% of the patients, whereas the other found the views to be satisfactory in 83%. The position of the placenta did not alter the probability of achieving a satisfactory view, but a fetus in the spine anterior position was associated with a significantly lower probability that the views were regarded as satisfactory for screening (odds ratio, 0.28; 95% confidence interval, 0.09–0.70; P < .05). Conclusions. This study suggests that STIC may assist with screening for cardiac anomalies at 18 to 22 weeks' gestation.     

Prenatal detection of velamentous insertion of the umbilical cord: a prospective color Doppler ultrasound study.

OBJECTIVE: Velamentous insertion of the umbilical cord, with a reported incidence of 1% in singleton pregnancies, has been associated with several obstetric complications including fetal growth restriction, prematurity, congenital anomalies, low Apgar scores, fetal bleeding and retained placenta. The aim of this study was to determine the feasibility of identifying velamentous insertion of the umbilical cord during routine obstetric ultrasound. DESIGN: This was a prospective, cross-sectional ultrasound study in 832 unselected second- and third-trimester singleton pregnancies. Color Doppler ultrasound was routinely performed to identify the placental cord insertion site. The role of three-dimensional (3D) ultrasound in evaluating the placental cord insertion site was also studied in a subset of 50 pregnancies from this population. RESULTS: The placental cord insertion site was identified in 825/832 (99%) cases. Visualization was not achieved in seven third-trimester pregnancies with a posterior placenta. A velamentous insertion was suspected prenatally in eight cases, seven of which were confirmed after delivery as velamentous and one as markedly eccentric (battledore placenta). 3D ultrasound performed poorly at evaluating placental cord insertion site, being less efficient due to poor-quality resolution and far more time-consuming than the combined use of gray-scale and color Doppler ultrasound. CONCLUSIONS: Velamentous insertion of the umbilical cord can reliably be detected prenatally by gray-scale and color Doppler ultrasound. 3D imaging had limited value in the evaluation of the placental cord insertion site in our subset of patients. Systematic assessment of the placental cord insertion site at routine obstetric ultrasound has the potential of identifying pregnancies with velamentous insertion and, therefore, those at risk for obstetric complications including vasa previa.     

Perinatal outcome in monochorionic twin pregnancies complicated by amniotic fluid discordance without severe twin-twin transfusion syndrome.

OBJECTIVES: To assess the natural history and perinatal outcome in monochorionic diamniotic twin pregnancies with discordant amniotic fluid volume without signs of severe twin-twin transfusion syndrome (TTTS). METHODS: This was an observational study of 84 consecutive monochorionic twin pregnancies which did not meet the criteria for severe TTTS and endoscopic laser coagulation of placental anastomoses at initial presentation. The population was subdivided into two groups. Group 1 consisted of 64 pregnancies (median gestational age, 20.1 (range, 15.6-24.7) weeks) with amniotic fluid discordance and no signs of congestive heart failure in the twin with the larger amniotic fluid volume (Twin 1) and positive end-diastolic flow in the umbilical artery of the twin with the smaller amniotic fluid volume (Twin 2). Group 2 (median gestational age, 19.1 (range, 16.0-24.4) weeks) consisted of 20 pregnancies with amniotic fluid discordance and intrauterine growth restriction (IUGR) (abdominal circumference < 5th percentile) in combination with absent or reversed end-diastolic (ARED) flow in the umbilical artery of Twin 2. After exclusion of one patient from Group 1, who opted for termination of pregnancy, nine patients in Group 1 and one in Group 2 developed severe TTTS, and laser coagulation was offered. The remaining 54 pregnancies of Group 1 were compared with the remaining 19 pregnancies of Group 2. RESULTS: Fetuses in Group 1 showed significantly higher survival rates (overall survival, 100/108 (92.6%) vs. 23/38 (60%), P < 0.0001; survival of both fetuses, 49/54 (90.7%) vs. 9/19 (47.4%), P = 0.0002) and median gestational age at delivery (33.6, (range, 27.6-37.8) weeks vs. 32.0 (range, 26.9-36.3) weeks, P = 0.0457). Overall, there was a significantly higher incidence of complications, defined as necessity for intrauterine intervention, fetal or neonatal death or delivery prior to 32 weeks, in Group 2 (Group 1: 30/63 (47.6%); Group 2: 16/20 (80%), P = 0.0188). CONCLUSIONS: Our data suggest that amniotic fluid discordance in monochorionic diamniotic twin pregnancies in combination with IUGR and umbilical artery ARED flow in one fetus represents an extremely high-risk constellation for adverse pregnancy outcome.     

Correlation between fetal gastric size and amniotic fluid volume

PURPOSE: Since abnormal conditions of the fetal digestive tract may alter both amniotic fluid volume and fetal gastric volume, we sought to determine whether amniotic fluid volume is correlated with fetal gastric volume in normal pregnancy. METHODS: A total of 280 fetal gastric size measurements were made prospectively from routine sonographic examinations of women with normal singleton pregnancies between 16 and 42 weeks of gestation. The fetal stomach was defined as the largest area including the pyloric site on transverse or oblique real-time sonographic scans. Gastric volume was calculated according to the formula for a prolate ellipsoid. The amniotic fluid index (AFI) was used for the evaluation of amniotic fluid volume. RESULTS: Both fetal gastric volume and AFI were significantly correlated with gestational age (R2= 0.422 and R2= 0.128, respectively). Only a weak correlation was found between gastric volume and AFI (R2= 0.036, p <0.001). On multivariate linear regression analysis adjusting for gestational age and fetal biometric measurements, gastric volume was not an independent and significant predictor of AFI. CONCLUSIONS: Although sonographically determined fetal gastric volume measurements appear to be useful in the assessment of fetal digestive tract anomalies, fetal gastric volume has no clinically significant effect on the amniotic fluid volume in normal pregnancy.     

Ultrasound estimation of amniotic fluid volume using the largest vertical pocket containing umbilical cord: measure to or through the cord?

OBJECTIVES: The purpose of this investigation was to determine the preferable method, either measuring to the umbilical cord or through the umbilical cord to the base of the pocket, of ultrasonically estimating amniotic fluid volume. SUBJECT AND METHODS: This was a prospective study carried out in singleton pregnancies undergoing a third-trimester amniocentesis. The amniotic fluid index (AFI) and single deepest pocket (SDP) were measured prior to amniocentesis. If measured spaces contained umbilical cord, measurements were made to and through the cord. Actual amniotic fluid volume was determined by the dye-dilution technique. RESULTS: One-hundred pregnancies were evaluated. Low dye-determined volume was identified in a significantly greater number of pregnancies using the AFI to the cord (7/28, 25%) compared to through the cord (2/28, 7%) (P = 0.025). The SDP technique to the cord was superior in low volumes (2/28, 7%) vs. (0/28, 0%) through the cord (although statistical significance could not be determined because there were no low through-the-cord measurements). CONCLUSIONS: For the detection of low amniotic fluid volumes, the AFI to the cord is better than through the cord. Measurement to the cord and through the cord had similar accuracy for both the AFI and SDP techniques in normal and high dye-determined amniotic fluid volumes.     

The 'spin' technique: a new method for examination of the fetal outflow tracts using three-dimensional ultrasound.

BACKGROUND AND OBJECTIVE: The prenatal detection of congenital heart defects remains one of the most difficult challenges for the sonologist/sonographer when performing the second- or third-trimester screening examination. The four-chamber view has been used for a number of years as the primary screening image for detection of heart defects, but the inclusion of the right and left outflow tracts increases the detection of cardiac malformations. One of the difficulties, however, is obtaining and interpreting two-dimensional images of the outflow tracts. This paper reviews a new technique using three-dimensional (3D) multiplanar imaging that allows the examiner to identify the outflow tracts within a few minutes of acquiring the 3D volume dataset by rotating the volume dataset around the x- and y-axes. METHODS: 3D multiplanar imaging of the fetal heart using static 3D or spatio-temporal image correlation (STIC) imaging allows the examiner to obtain a volume of data that can be manipulated along the x- and y-axes using reference points from the four-chamber view, five-chamber view, three-vessel view at the level of the bifurcation of the pulmonary arteries, and three-vessel view at the level of the transverse aortic arch and trachea. RESULTS: The full length of the main pulmonary artery, ductus arteriosus, aortic arch and superior vena cava could be identified easily in the normal fetus by rotating the volume dataset along the x- and y-axes. The vessels were identified using the four-chamber view, the five-chamber view, and the two three-vessel views. The technique was useful in identification of d-transposition of the great vessels and evaluation of the outflow tracts in hypoplastic left heart syndrome. CONCLUSION: 3D multiplanar evaluation of the fetal heart allows the examiner to identify the outflow tracts using a simple technique that requires only rotation around x- and y-axes from reference images obtained in a transverse sweep through the fetal chest.     

Placental vascular resistance using umbilical velocimetry in patients undergoing cesarean section for fetal distress

Peak systolic (S) to lowest end-diastolic (D) ratios (S/D) of umbilical velocimetry have been used to assess downstream placental vascular resistance and predict adverse pregnancy outcome. The purpose of this study is to assess S/D ratios in patients undergoing cesarean section for clinical fetal distress. Fifty-six patients were identified who had umbilical velocimetry performed during antepartum fetal surveillance (nonstress testing and amniotic fluid index) within 7 days of undergoing cesarean section for fetal distress at Women's Hospital (Los Angeles, CA). The mean gestational age at delivery was 36.5 +/- 2.5 weeks. Thirty (53.6%) patients had elevated S/D ratios (greater than 3), 24 (42.9%) had abnormal amniotic fluid indices, and 20 (35.7%) had abnormal nonstress testing. Group 1 (N = 30) patients delivered small-for-gestational-age (SGA) fetuses and group 2 (N = 26) patients delivered appropriately grown (AGA) fetuses. In group 1, 24 (80%) patients had abnormal S/D ratios and 16 (53.3%) had abnormal amniotic fluid indices, compared to only 6 (23.1%) with abnormal S/D ratios and 8 (30.8%) with abnormal amniotic fluid indices in group 2 (p less than .05). In contrast, 14 (53.8%) of the 26 patients in group 2 had abnormal nonstress testing compared to only 6 (20%) of the 30 patients in group 1 (p less than .05). Eighteen (69.2%) of the 26 patients in group 2 were post-term pregnancies; 20 (66.7%) of the 30 patients in group 1 had chronic hypertension, pregnancy-induced hypertension, or superimposed preeclampsia.(ABSTRACT TRUNCATED AT 250 WORDS)     

Is there a relationship between fetal weight and amniotic fluid index?

OBJECTIVE: To establish whether there is a relationship between the amniotic fluid index and estimated fetal weight in the third trimester. The presence of a relationship would require adjustment of amniotic fluid index to take account of estimated fetal weight with potential improvement in its prediction of adverse perinatal outcomes. METHODS: Paired measurements of amniotic fluid index and estimated fetal weight from 274 low-risk pregnancies enrolled in a longitudinal study of fetal growth. Measurements were made at fortnightly intervals from 30 weeks' gestation until delivery. A relationship between amniotic fluid index and estimated fetal weight was sought at gestational age week intervals of 30-32, 33-35, 36-38 and 39-41. RESULTS: One thousand and three pairs of measurements of amniotic fluid index and estimated fetal weight were available for analysis. Mean amniotic fluid index decreased towards term as expected. There was no correlation between amniotic fluid index and estimated fetal weight. Furthermore, there was no correlation between amniotic fluid index and estimated fetal weight at any of the gestational age intervals. CONCLUSIONS: There is no clinically relevant correlation between amniotic fluid index and estimated fetal weight. It should remain clinical practice to take account of gestational age when interpreting amniotic fluid index but it is not necessary to make adjustments for estimated fetal weight.     

Fetal syphilis: correlation of sonographic findings and rabbit infectivity testing of amniotic fluid

Fetal syphilis is the presumed diagnosis when the sonographic findings of fetal hydrops are found in the presence of maternal syphilis. In the absence of fetal hydrops, the diagnosis of fetal infection is difficult. We hypothesized that intra-amniotic infection would be accompanied by anatomic placental and fetal abnormalities that could be detected by ultrasonography. Rabbit infectivity testing (RIT), intratesticular inoculation of rabbits with amniotic fluid, can be used to confirm intra-amniotic infection with Treponema pallidum. Twenty-one gravidas with untreated early (primary, secondary, and early latent) syphilis underwent sonography and amniocentesis for RIT at 24 weeks of gestation or later. Antenatal sonographic findings were compared to their amniotic fluid RIT results. Hepatomegaly was significantly (P < 0.01) associated with amniotic fluid infection detected by RIT. Antenatal detection of hepatomegaly, which is probably the initial sonographic manifestation of hydrops fetalis, may ultimately identify the fetus affected with congenital syphilis.     

Fatal fetal outcome with the combined use of valsartan and atenolol

OBJECTIVE: To report a case of anhydramnios, pulmonary hypoplasia, very small placenta, and fetal death in a pregnancy complicated by chronic hypertension and diabetes mellitus that had been treated through the first 24 weeks of gestation with valsartan and atenolol. CASE SUMMARY: A 40-year-old Hispanic woman with well-controlled chronic hypertension and diet-controlled type 2 diabetes mellitus was treated with valsartan and atenolol until pregnancy was diagnosed at 24 weeks' gestation. An ultrasound examination revealed normal fetal growth and anatomy but anhydramnios (amniotic fluid index 0). Valsartan was discontinued, and amniotic fluid volume normalized within two weeks. Intrauterine fetal death was documented at 33 weeks' gestation. Labor was induced, with the delivery of a stillbom female fetus with small, hypoplastic lungs (weight 41% of expected) and an extremely small, 148-g placenta (weight 48% of the 10th percentile for gestational age). DISCUSSION: The use of valsartan, a selective angiotensin II receptor antagonist (ARA), in human pregnancy has not been reported, but this class of agents would be expected to cause fetal toxicity similar to that observed with angiotensin-converting enzyme inhibitors. This toxicity includes reduced perfusion of the fetal kidneys, resulting in anuria, oligohydramnios, and subsequent pulmonary hypoplasia. The small hypoplastic lungs and very small placenta were probably a consequence of valsartan and atenolol combination therapy. CONCLUSIONS: Resolution of anhydramnios after discontinuing valsartan is evidence for ARA-induced fetal toxicity. The pulmonary hypoplasia observed in the stillbom infant was a direct result of the severe oligohydramnios. The cause of fetal death nine weeks later is uncertain, but because the woman's chronic hypertension and diabetes were well controlled, we believe the primary cause was chronic placental insufficiency resulting from the previous combination of valsartan and atenolol.     

The use of the minimum projection mode in 4-dimensional examination of the fetal heart with spatiotemporal image correlation.

OBJECTIVE: The minimum projection mode (MPM) is a rendering algorithm available in some 3- and 4-dimensional ultrasonography systems that, in 1 image, allows the visualization of vessels and cystic anatomic structures located in different scanning planes. The objective of this study was to compare the information displayed in images obtained with the MPM with their corresponding 2-dimensional ultrasonographic images from fetuses with and without structural heart defects. METHODS: Thirty-two volume data sets acquired with the spatiotemporal image correlation technique from fetuses with (n = 15) and without (n = 17) structural heart defects were analyzed. Rendered images of the upper abdomen, 4-chamber view, and 3-vessel view were compared with the corresponding 2-dimensional images. Two independent observers with experience in fetal echocardiography reviewed these volume data sets using the MPM. The visualization rate of specific anatomic structures seen from a transverse sweep of the heart was recorded for each observer, and the interobserver agreement was assessed by statistical indices of agreement (kappa statistic). RESULTS: Images obtained by the MPM displayed more vascular structures than those of corresponding 2-dimensional images at the level of the 3-vessel view. For conotruncal anomalies, the minimum mode projected the aorta and pulmonary arteries in 1 single plane, facilitating the understanding of their spatial relationships. The interobserver agreement score was moderate to "almost perfect" for assessment of most anatomic structures in the upper abdomen, 4-chamber view, and 3-vessel view sections. However, interobserver agreement ranged from fair to poor for visualization of the left outflow tract, atrial septum, and flap of the foramen ovale. CONCLUSIONS: The MPM is an alternative rendering modality that facilitates visualization of normal and abnormal vascular connections to the fetal heart at the level of the 3-vessel view. This technique may be useful in prenatal diagnosis of conotruncal anomalies and in assessment of the spatial relationships of abnormal vascular connections in the upper mediastinum.     

First-trimester diagnosis of body stalk anomaly using 2- and 3-dimensional sonography

To determine the sonographic features of body stalk anomaly in the first trimester using 2-dimensional (2D) and 3-dimensional (3D) sonography, we conducted a retrospective analysis of all nuchal translucency sonographic examinations performed between January 1, 2006, and January 1, 2010, at our institution. From a total of 6952 nuchal translucency sonographic examinations, 4 cases of body stalk anomaly were identified. All cases were characterized by an absent umbilical cord and a large ventral wall defect with herniation of the abdominal contents into the extraembryonic coelom. Associated features included kyphoscoliosis, limb defects, and enlarged nuchal translucency measurements. Three-dimensional sonography was a useful adjunct to 2D techniques in determining the precise relationship of fetal structures to the amniotic cavity. Our case series emphasizes the importance of a thorough anatomic survey at the time of nuchal translucency screening and the value of 3D sonography in the delineation of first-trimester anomalies.     

Test performance of point-of-care ultrasound for gastric content

Objective

We sought to determine test performance characteristics of emergency physician ultrasound for the identification of gastric contents.

Three-dimensional sonography of the endometrium and adjacent myometrium: preliminary observations.

OBJECTIVE: By evaluating a series of patients undergoing pelvic sonography with routine 2-dimensional (2D) as well as 3-dimensional (3D) reconstructed images in the coronal plane, we attempted to characterize the types of additional information that can be obtained. METHODS: Ninety randomly selected patients undergoing transvaginal pelvic sonography were imaged according to a standard 2D protocol. A 3D uterine volume was then acquired in the sagittal plane and reconstructed in the coronal plane. The endometrium and surrounding myometrium were evaluated for architecture, masses, the relationship of masses to the endometrial cavity, and the anatomic configuration of the cavity. RESULTS: Ninety-one studies were obtained. Additional findings were obtained on the coronal view in 28 studies (30.8%). No additional findings were obtained in 63 studies (69.2%). Normal endometrial and myometrial findings were obtained by conventional 2D imaging in 42 of 91 patients. Of this group, additional findings were shown in 2 (5%) patients. Forty-nine of the 91 patients had abnormal findings by 2D imaging. Additional information was obtained in 26 (53%) of these patients. Added information included uterine anomalies, better definition of the endometrium, more accurate delineation and location of endometrial polyps, location of leiomyomas, visualization of cystic areas within the myometrium, and confirmation of the location of intrauterine devices. CONCLUSIONS: The 3D reconstructed view of the endometrium and adjacent myometrium appears to be most helpful after a conventional transvaginal study, showing abnormalities within the endometrium and myometrium but being of little added benefit if the conventional findings are normal.