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Objective To assess whether fetal cerebral vascular resistance is affected by the presence of nuchal cord(s) in the third trimester. Methods A set of 115 patients with well-established dates and singleton, appropriate for gestational age (GA), nonanomalous fetuses with nuchal cord(s) diagnosed with prenatalcolorDopplerimaging,between28and41 weeks and 115 controls matched for GA, were studied. Patients with hypertension, diabetes and autoimmune conditions were excluded. Doppler indices were obtained from the umbilical artery (UA) and the fetal middle cerebral artery (MCA) upon initial diagnosis of the nuchal cord. Results Of 115 GA-matched pairs of pregnancies, 103 fetuses had a single nuchal cord and 12 a double nuchal cord. No significant differences were noted in patient age, gravidity, parity, sonographically estimated fetal weight (SEFW), and growth centile at ultrasonographic diagnosis. Mean UA systolic/diastolic ratio (S/D) was 2.28 ± 0.32 and 2.36 ± 0.33 (P = 0.03) and UA resistance index (RI) 0.55 ± 0.06 and 0.57 ± 0.06 (P = 0.02) among study and controls, respectively. Mean fetal MCA S/D and RI did not differ significantly between the two groups (fetal MCA S/D 5.01 ± 1.28 and 5.04 ± 1.71 (P = 0.86), and mean fetal MCA RI 0.78 ± 0.06 and 0.78 ± 0.05 (P = 0.88)). No significant differences were noted in GA at delivery, incidence of meconium-stained amniotic fluid, birth weight, mode of delivery, neonatal gender, 1 and 5 minute Apgar scores, or UA pH and base excess, between study and control patients. Conclusion Fetal cerebral vascular resistance is not affected by the presence of nuchal cord(s) in the third trimester of pregnancy. Copyright  2005 ISUOG. Published by John Wiley & Sons, Ltd.

Objective To assess the feasibility of sonographic depiction of the fetal hard palate and secondarily to create nomograms throughout gestation of its sonographic width, length and area. Methods This was a cross-sectional study of pregnant patients between 15 and 41 weeks' gestation. Inclusion criteria consisted of well-established dates (confirmed by early ultrasound), and singleton, non-anomalous fetuses. Sonographic measurements obtained included biparietal diameter, head circumference, abdominal circumference and femur length. Fetal hard palate measurements included maximum width, maximum length and the calculated area. Tables were prepared depicting the estimated mean ± SD and 5th, 50th and 95th centiles at each gestational week between 15 and 41 weeks. Pearson's correlation coefficient and associated P-values for the relationships between fetal hard palate measurements and other sonographic measurements and coefficients of variation for each of the fetal hard palate measurements were calculated. Results The study included 602 consecutive patients. The mean maternal age was 28.7 ± 6.3 years, with median gravidity of 2 (range, 1–12) and parity 1 (range, 0–8). All attempts at obtaining fetal hard palate ultrasound measurements were successful. Mean fetal hard palate width (cm) = −0.73579345 + 0.11370432 × GA − 0.00083919 × GA2 and SD = −0.017842055 + 0.005142475 × GA, where GA is gestational age in weeks. Mean fetal hard palate length (cm) = −0.82020463 + 0.11767777 × GA − 0.00092801 × GA2 and SD = −0.043064317 + 0.006378869 × GA. Mean fetal hard palate area (cm2) = −2.40090641 + 0.17136556 × GA + 0.00097308 × GA2 and SD = −0.603647741 + 0.040740282 × GA. Sonographic measurements of the fetal hard palate width, length and area correlated significantly and strongly with gestational age (all P < 0.001) and significantly but less strongly with femur length (P = 0.004). Conclusion The fetal hard palate may be depicted sonographically with relative ease between 15 and 41 weeks' gestation and measurements of the fetal hard palate width, length and area correlate well with gestational age, biparietal diameter, abdominal circumference, sonographic estimated fetal weight, and femur length. Copyright © 2004 ISUOG. Published by John Wiley & Sons, Ltd.

Objective To test the null hypothesis that no correlation exists between transvaginal digital examination and the gold standard technique of intrapartum transabdominal ultrasound determination of fetal head engagement, and secondarily to compare the performance of attending physicians and senior residents in depicting fetal head engagement by transvaginal digital examination. Methods Two hundred and twenty-two consecutive patients in labor > 37 weeks' gestation with normal singleton cephalic-presenting fetuses and with either ruptured or intact membranes were included. Of these, 119 were nulliparous and 103 were multiparous. Transvaginal digital examinations were performed by either attending physicians or senior residents and were followed immediately by transverse suprapubic sonographic assessments by a single sonographer. The fetal head was considered engaged on transvaginal digital examination if the leading part of the fetal head was positioned at least at maternal ischial spine station 0, and on transverse suprapubic ultrasound if the fetal biparietal diameter was below the maternal pelvic inlet. Examiners were blinded to each other's findings and the effect of examiner experience on the rate of agreement between the two techniques was assessed. The effect of several other independent variables upon the rate of agreement between the two modalities was also assessed. Results Overall, transvaginal digital examinations were consistent with ultrasound determinations with a raw percent agreement rate of 85.6% (95% confidence interval (CI), 80.8–90.3); κ = 69.5% (95% CI, 59.4–73.9; P < 0.001). When stratified according to parity, the raw percent agreement rate for nulliparous patients was 81.5% (95% CI, 73.4–88.0); κ = 60.7% (95% CI, 45.9–64.1; P < 0.001), and for multiparous patients it was 90.3% (95% CI, 84.1–95.9); κ = 80.4% (95% CI, 63.0–87.5; P < 0.001). Maternal age, gravidity, maternal body mass index, gestational age, cervical dilatation, effacement, membrane status, ischial spine station of the fetal head, fetal head position at ultrasound assessment, birth weight and mode of delivery did not significantly affect rate of agreement. Parity did not affect examination consistency in multiparous patients, but in the whole group increasing parity increased the rate of agreement between modalities. Presence of combined spinal epidural anesthesia significantly increased the rate of agreement in the complete group and among multiparous but not among nulliparous patients. Conclusion These data demonstrate a high rate of agreement (85.6%) between ultrasound determination and transvaginal digital assessment of fetal head engagement. Examiner experience had no effect. These data support the use of intrapartum transabdominal assessment of fetal head engagement. Copyright © 2003 ISUOG. Published by John Wiley & Sons, Ltd.

Spontaneous antepartum septostomy occurring in monochorionic diamniotic twins is extremely rare. We present a case in which prenatal sonography at 26 weeks' gestation depicted a monochorionic diamniotic twin gestation with concordant fetal growth and findings suggestive of a true knot of the umbilical cord. At Cesarean delivery at 34 weeks' gestation, spontaneous antepartum septostomy with entanglement of the two separate umbilical cords was noted. This case suggests that the differential diagnosis of findings considered consistent with a true knot of the umbilical cord in monochorionic diamniotic twin gestations, should include spontaneous antepartum septostomy and umbilical cord entanglement.

Objective. The purpose of this study was to create reference range nomograms of the axial fetal neck circumference (FNC) and fetal neck area (FNA) throughout gestation. Methods. This prospective crosssectional study involved pregnant patients between 14 and 40 weeks’ gestation. Inclusion criteria consisted of well-established dates (confirmed by early sonography) and nonanomalous singleton fetuses with intact fetal membranes. Sonographic measurements included biparietal diameter, head circumference, abdominal circumference, femur length, humerus length, transcerebellar diameter, and sonographically estimated fetal weight. Axial FNC and FNA values were calculated as means of 3 separate measurements. The 5th, 50th, and 95th percentiles were estimated at each week of gestational age (GA) by least squares regression for the mean and SD of the FNC and FNA as functions of GA. R 2 and associated P values for the relationships between the FNC, FNA, and other sonographic biometric measurements were calculated. Results. The study included 720 consecutive patients. The mean maternal age ± SD was 27.3 ± 6.6 years; median gravidity, 3 (range, 1‐13); and median parity, 1 (range, 0‐10). The following equations were devised: mean FNC (centimeters) = ‐11.85 + 1.687 × GA (weeks) ‐ 0.043 × GA 2 + 0.0004951 × GA 3 ; SD FNC = 3.15 ‐ 0.3823 × GA + 0.01733 × GA 2 ‐ 0.0002179 × GA 3 ; mean FNA (square centimeters) = 37.29 ‐ 7.0 × GA + 0.4717 × GA 2 ‐ 0.01245 × GA 3 + 0.0001222 × GA 4 ; and SD FNA = 7.08 ‐ 0.9413 × GA + 0.04135 × GA 2 ‐ 0.0004829 × GA 3 . Both the FNC and FNA

Lipomas of the vulva are rare benign tumors that consist of mature fat cells often interspersed with strands of fibrous connective tissue. They arise from the vulvar fatty pads and present as soft, multilobulated subcutaneous neoplasms. Histological examination reveals a thin capsule surrounding a lobular proliferation of lipocytes. Liposarcomas of the vulva have been described rarely. We present the sonographic findings of a large lipoma of the vulva, and demonstrate the contribution of topical application of a high-frequency transvaginal transducer in depicting lobular structural features, characteristic of this soft tissue tumor.

Objective: To evaluate the sensitivity, specificity, positive predictive value and negative predictive value to determine a low central venous pressure (0–5 mmH2O) using ultrasound to determine the central venous pressure compared to invasive central venous pressure measurement. Method: Indigent pregnant South Africans with severe maternal disease managed in a tertiary setting. Since 2003 all the obstetric patients who required the placement of a central venous pressure line or a Swan-Ganz catheter were asked to participate in a study comparing ultrasonic evaluation of the heart with the invasive monitoring of the heart. If the patient agreed, the catheters were placed and the measurements were obtained, thereafter an ultrasonographic examination of the patient’s heart was performed. During this examination the diameter of the inferior vena cava was measured 2.5 cm from the entrance into the atria. The percentage of collapse during inspiration was also evaluated and according to this, the central venous pressure was estimated. This value was correlated with the value obtained with the invasive technique. The measurements were initially performed using a standard cardiac probe. Currently the measurement is performed using the standard abdominal probe that is used for normal obstetric ultra sound examinations. (The technique will be demonstrated using a video presentation). Results: A total of 33 measurements were obtained. The sensitivity was 92%, specificity was 95%, positive predictive value was 92% and the negative predictive value was 95% and the accuracy was 94% for the central venous pressure between 0 and 5 mmH2O. Conclusion: Non-invasive CVP measurements using standard obstetric ultrasound equipment can be used to predict a low central venous pressure in the place of invasive CVP monitoring. This can be valuable in managing an ill obstetric patient when it is not safe to place a CVP line. OP13.07 Nomograms of axial fetal cerebellar hemisphere circumference and area throughout gestation