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Objective. The aim of this work was to review the technical aspects and clinical applications of three-dimensional ultrasonography in gynecologic imaging. Methods. With the use of a computerized database (MEDLINE), articles on three-dimensional ultrasonography were reviewed. Other pertinent references were obtained from the references cited in these articles. In addition, we reviewed our own clinical experience over the past 7 years. Results. Numerous applications of three-dimensional ultrasonography have been reported, including imaging of the uterus, the endometrial cavity, adnexa, and the pelvic floor and color and power Doppler applications. The accuracy of volume calculations and the networking opportunities with three-dimensional ultrasonography have also been reported. Technical problems and limitations of this technique are summarized. Conclusions. Three-dimensional ultrasonography has proved to be a useful imaging tool for clinical problem solving in gynecology, especially in imaging the uterus and uterine cavity.

n 2005, the American Institute of Ultrasound in Medicine (AIUM) will celebrate its 50th anniversary. The first 50 years of the AIUM are closely intertwined with the evolution of ultrasound and with the pioneers and developments responsible for propelling ultrasound into its position as one of the leading imaging modalities in North America and around the world. I am delighted that Beryl R. Benacerraf, MD, editor-in-chief of our prestigious Journal of Ultrasound in Medicine, asked me to write this introductory article in honor of the AIUM’s first 5 decades. The AIUM has a number of activities and items planned for these next 2 years. First and foremost will be a series of articles on the history of ultrasound, which will be published in our journal from this June until our June 2005 annual convention in Orlando, Florida. These articles will highlight the history of ultrasound from its earliest days to the present. The articles will be written by key ultrasound pioneers and preeminent scholars of the AIUM and will describe the remarkable progress and changes that have taken place in ultrasound over these 5 decades. Among the topics expected to be addressed are abdominal, breast, cardiology, contrast-enhanced, emergency, intraoperative, musculoskeletal, obstetric/gynecologic, ophthalmologic, pediatric, retroperitoneal, and vascular ultrasound, as well as changes in AIUM administration/governance, bioeffects, instrumentation, medicolegal issues, and neurosonology. Today, the AIUM is known and respected around the world as a unique, dynamic, multidisciplinary organization, blending clinical and basic science in the pursuit of excellence in ultrasound. It is a society of more than 8200 members and represents a true cross section of ultrasound professions, including physicians (sonologists) from almost all diagnostic fields, sonographers, basic scientists, engineers, and ultrasound industry representatives. It is difficult to believe that only a little more than half a century ago, few people had heard of ultrasound, and even fewer could describe how it could be used in medicine. Today, virtually everyone knows about diagnostic ultrasound, and many have had the firsthand experience of undergoing an ultrasound examination. In fact, by some estimation, more than 80 million ultrasound examinations are now performed annually in the United States. In the 1940s and 1950s, when ultrasound was just emerging as a diagnostic technique, display technology was largely limited to Aand M-mode tracings and crude bistable static B-mode images. At that time, the only nonresearch clinical application for ultrasound was for therapy rather than diagnosis. High-power, low-frequency ultrasound was already widely used to provide therapeutic heating of deep tissues.

The objective of this study was to assess the value of combining transvaginal sonohysterography with three-dimensional multiplanar ultrasonography to optimize assessment of the uterus. To make this assessment, we compared findings on three-dimensional sonohysterography with those on two-dimensional sonohysterography and X-ray hysterosalpingography. Of 20 women who underwent three-dimensional sonohysterography for various indications, 13 also underwent two-dimensional sonohysterography, and 12 had X-ray hysterosalpingography. We reviewed the 3 types of examinations separately and compared the standard techniques with three-dimensional sonohysterography to determine whether three-dimensional sonohysterography provided additional information. In 9 (69%) of 13 comparisons between three-dimensional sonohysterography and two-dimensional sonohysterography and in 11 (92%) of 12 comparisons between three-dimensional sonohysterography and X-ray hysterosalpingography, three-dimensional sonohysterography was advantageous. The coronal plane was most useful for displaying the relationship between lesions and the uterine cavity. Three-dimensional sonohysterography provided additional information compared with standard accepted techniques in the vast majority of women.

Objective To evaluate the feasibility and accuracy of fetal gender assignment from three-dimensional ultrasound (3D US) data at 10–24 weeks' gestation. Methods Three-dimensional ultrasound volume data on 47 fetuses were reviewed and divided into groups: 10–14, 15–18, and 19–24 weeks. Fetal genitalia were studied in axial and sagittal planes for gender assignment, using published criteria. The most valuable plane for assignment was noted. Gender assignment was compared with gender at birth. Results Gender assignment was possible in 44 of 47 fetuses; 25 assigned male and 19 female. Between 10 and 14 weeks the mid-sagittal plane alone was diagnostic for all fetuses. Accuracy of assignment between 11 and 14 weeks was 100%. Between 15 and 18 and 19 to 24 weeks, male assignment was 100% accurate. Female assignment was 100% accurate between 15 and 18 weeks. Accuracy decreased to 60% in the 19 to 24 week group, however, in two of the five cases in which gender was wrongly assigned to be male, the assignment was prospectively considered doubtful due to poor resolution of volume data. Excluding these two cases, accuracy for female assignment in the 19–24 week group was 100%. Conclusion Using 3D US, gender assignment was possible in 44 of 47 of fetuses, as early as 11 weeks' gestation. In early gestation, 11–14 weeks, accuracy of male and female gender assignment was 100%. Copyright © 2000 International Society of Ultrasound in Obstetrics and Gynecology

Specially developed high-resolution real-time ultrasound transducers (12.5 and 20 MHz) on the tip of endoluminal catheters were inserted into the endometrial canal to evaluate the usefulness of this approach. Uterine abnormalities, most confirmed by biopsy, surgery, or both, were detected in 12 patients, including submucosal myomas, nabothian cysts, endometrial polyps, synechiae, and endometrial and cervical carcinoma. In one case the catheter was directed under hysteroscopic guidance into a fallopian tube, demonstrating its potential usefulness in this region. In 4 of the 12 cases in which a hysterectomy was performed, an in vitro ultrasound examination of the organ was performed, which confirmed the initial in vivo ultrasound impressions. Anatomic cross-sectional slices of the uterus resulted in excellent correlation with the ultrasound findings. These preliminary results suggest that this new sonographic procedure will become an important diagnostic tool, supplementing abdominal and endovaginal ultrasound approaches.

To date, there have been 25 studies attempting to correlate biparietal diameter and gestational age; of these, 17 meet specific criteria and thus are included in this evaluation. Although all studies have shown an increase in biparietal diameter with advancing gestational age, between 17 wk and term there is a discrepancy of approximately 3 wk. In this evaluation the charts are compared and the variations analyzed. An ideal table is constructed by combining the mean gestational age, calculated from a statistical analysis, and the variation at each millimeter point, determined by comparison of all the studies. It is hoped that this new 90% composite table, which consists of a range of gestational ages in weeks for each biparietal diameter, will not only provide more realistic indications of fetal age but also will serve as a reminder to sonographers, obstetricians, and patients of the relative accuracy and variations of biparietal diameter measurements.

Various formulas have been employed to compute the circumference of an ellipse. These formulas can be separated into three groups: formulas for a circle, formulas for an incorrect ellipse, and a very complicated formula for a correct ellipse. The errors caused by the first two groups are termed systematic because they occur every time that one of these formulas is used. When measuring fetal head circumference, the errors increase as the fetal head is more ellipsoid, becoming more than 1% when the ratio of the biparietal to fronto-occipital diameter decreases to less than .70. Near term, when the fetal head is large, this could create an error in predicting gestational age of almost .8 weeks. The third group is associated with mathematical random errors because of the difficulty in using a cumbersome equation. All of these formulas and their shortcomings are analyzed. A calculation for the correct circumference of an ellipse is proposed using the simple formula for a circle times a correction factor. The correction factor depends solely on the ratio of the biparietal to fronto-occipital diameter. This formula should minimize random errors and eliminate systematic errors in the calculation of fetal head circumference and will permit a more accurate analysis of fetal age.

We report two sib fetuses with nuchal systic hygroma and cleft palate. This condition is probably recessively inherited as the parents have normal chromosomes (G-banded) and the fetuses were of opposite sex. Nuchal cystic hygroma is a nonspecific malformation, which reflects a delay in development of the connection between the jugular lymph sacs and the internal jugular vein. This fetal malformation and its equivalent in the adult, neck webbing, has been reported to be a part of a variety of genetic malformation syndromes. Some suggestions for counseling parents of an affected fetus are made: If the chromosome karyotype of an affected fetus is unknown, ultrasound examination, rather than AFP studies, is suggested for future pregnancies.

Seven cases of heterozygous achondroplasia were examined in utero. Although the head shape and growth were normal, the initially normal femur length showed a decrease in growth and fell below the lower 99 per cent confidence limit in all cases. The time of presentation of achondroplasia varied between 21 and 27 gestational weeks. This study suggests that the diagnosis of achondroplasia can be reasonably made when the femur is abnormally short. When the femoral length is appropriate prior to 30 weeks, more caution should be taken in interpretation. Because of the variability in presentation, the fetus could be normal or still could be affected.

The prolate ellipse formula has been shown to be inaccurate and inconsistent in the calculation of total uterine volume. The stepped area-to-volume technique has proven to be both accurate and consistent and provides a value equal to the true uterine volume. When these true volumes were plotted on previously published graphs of total uterine volume derived from the prolate ellipse formula, the graphs were found to be inaccurate. New graphs based on normal values have been constructed, comparing total uterine volume with both biparietal diameter and average gestational age. When 26 abnormal values were plotted on the total uterine volume versus biparietal diameter graph, almost all fell outside the 90 per cent confidence limits. Seven of the abnormal value were from fetuses found to have growth retardation. Six of these cases, including two not appreciated either clinically or ultrasonographically, were detected by this method. The stepped area-to-volume technique should allow reconsideration of the total uterine volume concept and aid in the detection of the subtle changes in uterine size.

The purpose of this research effort was to establish a physical basis for the development of an accurate noninvasive technique to differentiate between mature and immature fetal tissues, particularly the lung and placenta. The research utilized RF waveform analysis via a microcomputer-based digital processing system interfaced directly to a standard real-time clinical diagnostic ultrasound instrument. Differences between the frequency spectra of the RF waveforms for mature and immature fetal tissues could be demonstrated in accordance with proposed tissue models.

Well-established roles for Doppler ultrasound assessment of renal transplants include postoperative evaluation for vascular occlusion and detection of renal artery stenosis. Doppler studies can often differentiate rejecting transplants from those that normally function. While very high Doppler indices are specific for rejection, waveforms in acute tubular necrosis may be abnormal. Mild cases of rejection may have normal waveforms. Further investigation is needed to determine the role of Doppler methods in graft dysfunction and to establish methods to improve their specificity.

Microcephaly (small head) is clinically important only if there is concomitant micrencephaly (small brain). Extensive studies on patients in mental institutions have shown that there is close correlation among microcephaly, micrencephaly, and mental retardation when the head is more than three standard deviations below the norm. If the small head is less than two standard deviations below the norm, no strong correlation exists with eigher small brain or mental retardation. High-resolution ultrasound permits imaging of the fetal head in utero, allowing accurate evaluation of head size and detection of intracranial anomalies. The microcephalics detected in utero over a 2-year period form the basis of this series, showing close correlation with the known clinical data on children with microcephaly. An approach to ultrasound detection and evaluation of fetal microcephaly is proposed.

Fourteen men referred for ultrasound evaluation of breast enlargement had ultrasound mammography using water path techniques. Gynecomastia, both the localized type and the diffuse type, could be differentiated from the normal soft tissues of the chest wall on the B-scans. Among nine cases of men who underwent excision, there were six cases of gynecomastia, two lipomas, and one biopsy revealed normal subcutaneous tissue. The ultrasound B-scan images are correlated with the histologic findings in these nine cases. Ultrasound mammography using water path techniques is a useful imaging examination for male breast enlargement.

Twenty-one patients with the clinical diagnosis of varicocele were evaluated with static and superficial organ scanners. The sonogram was able to image the dilated scrotal veins in all of these cases. The small, clinically subtle varicocele could be demonstrated only with high-resolution, dedicated real-time small-parts scanners, whereas larger lesions could also be imaged with B-mode contact equipment. Varicoceles are a well-documented cause of male infertility amenable to surgical treatment. From this study it is felt that ultrasonography can accurately detect varicoceles. It can be used as a screening procedure so that only those men requiring therapy need undergo more extensive and complicated diagnostic procedures.

Hand-held sonomammography was used intraoperatively to localize 52 masses in 45 women in an out patient operating suite. All but five women had a positive X-ray mammogram. The ultrasound mammogram was able to identify all lesions. In 42 women studied by a preoperative ultrasound examination before the operating room procedure, all the masses were successfully identified. Precise localization was successfully performed in the operating room before sterile preparation in less than 10 minutes. Relocalization after incision in the sterile operating field was necessary in two cases. This technique requires no ionizing radiation and expedites outpatient surgical removal of the lesion. Of the 52 masses, there were 32 fibroadenomas, three carcinomas, three cysts, six cases of focal fibrous mastitis, and eight patients with focal fibrocystic disease. In patients with positive sonograms for nonpalpable masses, ultrasound localization is a fast, accurate alternative to X-ray needle placement.

A long-axis real-time ultrasonic transrectal probe was utilized in transperineal biopsies to detect three nonpalpable prostate cancers. It was found that ultrasonically guided percutaneous perineal biopsy allows for the accurate placement of the biopsy needle tip into suspicious areas of the prostate. Ultrasonographic examination prior to biopsy is recommended to provide confirmation of palpable masses and to reveal other suspicious but not clinically suspected areas.

Polyorchidism, or multiple testes, is a rare condition that has been referred to in both medical literature and mythological folklore. Curious attributes have been ascribed to men with this condition, including supposed increased sexual prowess and virility. In the medical literature, the examples of supernumerary testicles have demonstrated only one additional testis. The first proven case of an extra testicle was by Lane, in 1895. Boggon reviewed 11 additional cases in 1933, and numerous other cases have been reported since then. To date, there has not been a preoperative ultrasonographic study that adequately describes this phenomenon.