The aim of this prospective cross-sectional study was to establish new Doppler reference curves for peak blood flow velocities (Vmax, Vmean, Vmin) and impedance indices (PI, RI) of the middle cerebral artery at 18-42 weeks of gestation by an automatic wave form analysis integrated into the ultrasound device. In 962 low-risk pregnancies, blood flow velocities were derived from the middle cerebral artery with pulsed color Doppler ultrasonography. Reference curves were constructed for the individual parameters based on a growth function from a four-parameter class of monotonic continuous functions according to the smallest square principle for maximum blood flow velocities, as well as on a polynomial function for resistance indices. Further assessed was intra-observer reliability. The results obtained for maximum blood flow velocities demonstrate a continuous increase (Vmax = 26.8 cm/s to 59.1 cm/s, Vmean = 11.2 cm/s to 29.7 cm/s and Vmin = 4.9 to 15.8 cm/s) over the period from 18 to 42 weeks of gestation. In contrast, reference curves for the pulsatility and the resistance index are characterized by a parabolic pattern (18 weeks: 1.5; 28 weeks: 1.9; 42 weeks: 1.1 and 18 weeks: 0.68; 28 weeks 0.8; 42 weeks: 0.61). Intraobserver reliability for PI, RI, Vmax, Vmean, and Vmax were 87%, 83%, 80%, 83% and 93%, respectively. At constant measurement conditions, the reference ranges for blood flow velocities and impedance indices in the middle cerebral artery established by this study were found to be a useful non-invasive tool in risk assessment for fetal anemia, as well as in the Doppler ultrasound observation of the course in fetuses with intrauterine growth restriction.

Within the past five years, 3D ultrasonography has developed to the degree that it offers both the patient and the examiner an entirely new visual experience in prenatal diagnosis. With the system described here (Kretz-technik, Austria), any desired plane can be displayed within the stored volume, and within seconds a high-quality 3D surface or transparent image can be calculated and displayed on the ultrasound monitor without need for an external workstation. All of this can be performed routinely in the clinical setting. Since 1989 we have routinely examined a total of 458 fetuses (242 normal and 216 with anomalies) between 16 and 38 weeks of gestation, supplementing our conventional 2D ultrasound scans with a 3D examination using an abdominal volume transducer. A comparison of the 2D and 3D techniques shows that 3D provides a diagnostic gain in a large percentage of cases (64.2%). The simplest 3D technique of the orthogonal image display provided a diagnostic gain in 46.2% (61/132) of the cases owing to the accurate topographic depiction of the desired image plane. The combined 3D display (orthogonal format plus a 3D surface or transparent view) provided a diagnostic gain in 71.5% (233/326) of the cases. This higher percentage resulted from the additional 3D surface reconstruction, the ability to view and evaluate the fetus from various angles, the ability to determine the exact size of a fetal defect, the depiction of skeletal anatomy in the transparent mode, and the improved delineation of complex malformations. Problems with 3D imaging are encountered in patients with pronounced oligohydramnios, which prevents surface reconstruction, and in the examination of moving objects, which produce motion artifacts.

No abstract

Thirty patients with unruptured ectopic pregnancy (4–10 weeks’ gestation) were treated locally with methotrexate (MTX) under sonographic guidance. The transvaginal puncture was performed under analgesic sedation using an automatic puncturing device. Local MTX therapy was successful in 25 patients (83.3%). Eighteen of these patients had received a single MTX instillation with a total dose of 10 mg, 7 patients had received a second instillation with 10 mg because of plateauing hCG levels after the first instillation. In 5 patients MTX therapy was unsuccessful. Surgical intervention was necessary within 4 h to 15 days after MTX treatment, due to severe tubal bleeding (n = 1) or the development of an increasing peritubal hematoma (n = 4). Patients with an outer trophoblast diameter < 1.5 cm could be treated successfully in all cases (25/25). In patients with hCG values > 5,000 mlU/ml the success rate was 70% (7/10) and in patients with demonstration of cardiac activity of the embryo 63% (5/8). The fluid aspirated from the ectopic cavity showed an average hCG concentration that was 53 times higher than in the serum. The decline in hCG to values below 10mlU/ml ranged between 7 and 75 days (mean 28 days). The hysterosalpingography performed 4–6 months after MTX therapy showed tubal patency on both sides in 85.7% of the patients examined. In the meantime 4 of these patients gave birth to healthy children.

Vasa previa is a rare condition. However, since the increase in assisted reproductive technologies (ARTs), clinicians are more frequently confronted with this complication. In this study, we present five cases of vasa previa prenatally diagnosed from a tertiary referral hospital with approximately 2000 births yearly.