Faculty Bibliography

Transabdominal sonography has been, for the past two decades, used as an effective diagnostic and research tool in obstetrics. It is predominantly used in the second and third trimesters of gestation. Its use in the first trimester is relatively limited and mostly diagnostic in nature. The introduction of the higher frequency transvaginal transducer probe, with its higher resolution of the images, opens new possibilities to study early gestation. We studied embryonic development in 38 well-dated and normal pregnancies. A well-defined intrauterine gestational sac could be seen at 4 weeks and 1 to 4 days of menstrual age. The beta-subunit of human chorionic gonadotropin level at this time was 450 to 750 mlU/ml. Structures such as the yolk sac, membranes, ventricular system in the brain, musculoskeletal system, and cord were described and illustrated. Textbooks and atlases were used for comparative purposes. High-resolution transvaginal sonography will facilitate first-trimester perinatology

Transvaginal sonography was compared with transabdominal sonography in 35 women with suspected placenta previa. The transvaginal sonographic technique did not result in vaginal bleeding in any of the patients. The internal os and its relationship to the location of the placenta were visualized by transvaginal sonography in all patients, but only in 24 patients (69%) by transabdominal sonography. Transvaginal sonography ruled out placenta previa in 13 cases thought to be placenta previa by abdominal sonography. The transvaginal diagnosis in these 13 patients was confirmed at delivery. Thirty-four of the 35 women have been delivered. The diagnosis at delivery confirmed the transvaginal sonographic diagnosis in 29/34 cases and the transabdominal diagnosis in 16/34. Transvaginal sonography did not predict the delivery diagnosis in five patients who were erroneously believed to have placenta previa by both sonographic techniques

Ultrasonography has become an important tool in infertility and obstetric practice. Its use in gynecology, while effective, has been less. This article describes the use of a high-frequency 6.5 MHz probe specially designed for intravaginal use. The technique is presented, along with a description of its uses and findings by organ. Patient acceptance has been universal. Its high resolution makes this technique more useful in general gynecologic practice

Transvaginal sonography with a high-frequency probe, a recent development gaining clinical application, obtains better image resolution of deep pelvic organs. Uses of transvaginal sonography include diagnosis and treatment in gynecology, infertility, and early pregnancy. Acceptance by health-care providers and patients is widespread. Advantages include greater clinical capability, increased efficiency, and reduced costs. The nurse's role in patient education and management is a vital component of the care of the patient undergoing transvaginal sonography

This study was performed in order to investigate the fetal electrocardiogram (FECG) during uterine contractions associated with normal labor. Twenty-five patients with low risk pregnancy between 38-41 weeks gestation were studied during the active stage of labor. Both FECG and intra-uterine pressure are obtained in a conventional manner and are continually sampled into the computer. The FECG is averaged point-to-point, synchronized to the peak of the R-wave. This is performed by a QRS detection algorithm which is based on a digital analysis of slope, amplitude and width. A digital band-pass filter composed of cascaded high-pass and low-pass filters reduces false detections and permits the use of auto-adjustable low thresholds. A separate averaging is performed on the T-wave in order to prevent attenuation due to variable R-T interval. The T wave is subsequently aligned in time and position to the rest of the QRS complex. A significant increase was observed in the T/QRS amplitude ratio during the first half of the uterine contraction. Such an increase was also observed in the short and long-term FHR variability. No significant changes were observed in the other components of the FECG. In conclusion, by implementing a computer based system it is possible to analyse the FECG during labor. Based on this and previous studies it may well prove to be a sensitive indicator of fetal condition

An in vitro model, simple to assemble, consisting of a fresh placenta suspended in a water bath, is presented for the training of physicians interested in practicing ultrasound-guided fetal intravascular needle placement

The use of transabdominal/transvesical sonography in gynecologic diagnosis is limited by the physical properties of the transducers used as well as the lack of sufficient acoustic interfaces. Therefore, delicate tubal structures cannot be visualized adequately. Transvaginal application of a 6.5-MHz transducer probe (with a 10-mm crystal) enables the effective use of higher frequencies, enhancing resolution. This higher resolution improves picture quality and increases potential diagnostic power in evaluating the female pelvis in general and the fallopian tube in particular. This report presents the sonographic picture of the normal and pathologic tube. Tubal pathology should be described in terms of the tubal cavity, walls, and content, as well as location and mobility. The more frequently encountered clinical entities, such as the fluid-filled tube, tubo-ovarian inflammatory processes, and tubal gestation are discussed

The technique for reduction of the number of embryos was applied in a patient who conceived following IVF and transfer of six embryos. On the 10th week of gestation, the number of embryos was reduced from five to three by an U/S-guided intra-uterine procedure. Two healthy girls and a boy were delivered in the 36th week by cesarean section. No trace of the other two fetuses was found. The moral and technical aspects of partial preventive termination of multiple pregnancy are discussed