Obstetric and gynecologic ultrasound curriculum and competency assessment in residency training programs: consensus report.

Ultrasound imaging has become integral to the practice of obstetrics and gynecology. With increasing educational demands and limited hours in residency programs, dedicated time for training and achieving competency in ultrasound has diminished substantially. The American Institute of Ultrasound in Medicine assembled a multi-Society Task Force to develop a consensus-based, standardized curriculum and competency assessment tools for obstetric and gynecologic ultrasound training in residency programs. The curriculum and competency-assessment tools were developed based on existing national and international guidelines for the performance of obstetric and gynecologic ultrasound examinations and thus are intended to represent the minimum requirement for such training. By expert consensus, the curriculum was developed for each year of training, criteria for each competency assessment image were generated, the pass score was established at or close to 75% for each, and obtaining a set of five ultrasound images with pass score in each was deemed necessary for attaining each competency. Given the current lack of substantial data on competency assessment in ultrasound training, the Task Force expects that the criteria set forth in this document will evolve with time. The Task Force also encourages use of ultrasound simulation in residency training and expects that simulation will play a significant part in the curriculum and the competency-assessment process. Incorporating this training curriculum and the competency-assessment tools may promote consistency in training and competency assessment, thus enhancing the performance and diagnostic accuracy of ultrasound examination in obstetrics and gynecology. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Educational impact of faculty review on radiology residents' radiographic interpretations.

The objective of this study was to analyze the improvements in film reading performance made by radiology residents during their first six months of training. Five first-year residents and eight radiologic technology students each interpreted two of three matched sets of 39 films under two conditions. One set's readings were reviewed by a staff radiologist, while the other's were unreviewed. Six months later, each observer read all three sets. After the first six months of training, residents improved their reporting of findings. There was less improvement in technologists' readings. Review and instruction by staff, both in the laboratory and daily work settings, appeared to contribute to improved performance. Accuracy of residents' final diagnosis did not improve significantly. We conclude that a training system in which residents' film interpretations are reviewed by staff can lead to improved resident performance. When studied in a longitudinal fashion, these improvements are detectable within six months. This teaching system is used in many radiology departments.

FL/AC ratio: poor predictor of intrauterine growth retardation.

Early antenatal detection of intrauterine growth retardation (IUGR) may decrease the associated perinatal morbidity and mortality. A parameter based on sonographically measured femur length (FL) and abdominal circumference (AC), expressed as FL/AC X 100 and termed the FL/AC ratio, has recently been proposed by Hadlock et al as an age-independent predictor of IUGR. We studied 285 normal and 37 IUGR fetuses to verify that the FL/AC ratio is independent of gestational age (GA) and to assess its value as a predictor of IUGR. Our results confirm that the FL/AC ratio is age-independent above 20 weeks and that its mean value differs in normal (22.4 +/- 1.7) and IUGR (23.7 +/- 1.4) fetuses (P less than .01, t-test). Because of considerable overlap between these two groups, however, there is no cutoff value for the FL/AC ratio that yields both a high sensitivity and a high specificity, or that leads to a high positive predictive value. With a cutoff of 23.5, for example, the sensitivity is 56% and the specificity 74%, and, even assuming an IUGR prevalence rate of 10%, the likelihood of IUGR in a fetus with an FL/AC ratio above the cutoff is only 19%. We conclude that the FL/AC ratio, though an age-independent measure whose mean value differs in normal and IUGR fetuses, is not clinically useful as a predictor of IUGR.

Cardiac output in a fetus with erythroblastosis fetalis: assessment using pulsed Doppler.

Pulsed Doppler studies of left and right ventricular outputs were obtained over time in a hydropic fetus with erythroblastosis fetalis. Despite severe anemia, cardiac outputs were within the normal range and remained normal after in utero percutaneous intravascular transfusions, which reversed the hydrops. The measurement of cardiac output in utero provides direct evidence that high-output failure due to anemia is not the mechanism for hydrops in erythroblastosis fetalis.

Sonographic diagnosis of partial hydatidiform mole.

We undertook a study to determine whether partial hydatidiform mole could be distinguished from other cases of first-trimester missed abortion using ultrasound. Scans from 22 cases of pathologically proved partial hydatidiform mole and 33 cases of first-trimester missed abortion were independently reviewed by three radiologists, each unaware of the final pathologic diagnosis. Using a standard data form, each radiologist recorded the dimensions, shape, and contents of the gestational sac, the sonographic appearance of the decidual reaction/placenta and myometrium, and the presence or absence of adnexal cysts. The following two criteria were found to be significantly associated (P less than .05) with the diagnosis of partial mole: 1) ratio of transverse to anteroposterior dimension of the gestational sac greater than 1.5, and 2) cystic changes, irregularity, or increased echogenicity in the decidual reaction/placenta or myometrium. There was high interobserver correlation for both criteria, as measured by the kappa statistic. In 50% of the cases, either both or neither of these criteria were met. When both criteria were met, the frequency of partial mole was 87%; when neither criterion was met, the frequency of missed abortion was 90%. These results indicate that ultrasound can be of value in predicting a high likelihood of partial mole prior to curettage.

A randomized, double-blind trial of a gonadotropin releasing-hormone agonist (leuprolide) with or without medroxyprogesterone acetate in the treatment of leiomyomata uteri.

A randomized, double-blind study was performed on 16 women to compare the efficacy of daily subcutaneous (SC) injections of leuprolide acetate (LA; TAP Pharmaceuticals, North Chicago, IL) plus oral placebo tablets (group A, n = 7) with SC LA plus oral medroxyprogesterone acetate (The Upjohn Company, Kalamazoo, MI; group B, n = 9) in the treatment of leiomyomata uteri. Patients in group A had a significant reduction in uterine size from a pretreatment volume of 601 +/- 62 cm3 (mean +/- standard error) to a mean uterine volume of 294 +/- 46 cm3 at 24 weeks of therapy (P less than 0.01). Group B patients had a reduction in uterine volume from 811 +/- 174 cm3 to 688 +/- 154 cm3, which was not statistically significant. However, only one patient in group B experienced hot flashes, whereas six patients in group A had this symptom (P less than 0.01). Both groups demonstrated significant increases in mean hemoglobin concentrations, hematocrits, and serum iron levels at 24 weeks of therapy compared with pretreatment levels.

A randomized, placebo-controlled, double-blind study evaluating leuprolide acetate depot treatment before myomectomy.

Eighteen premenopausal women with symptomatic leiomyomata uteri were enrolled in a stratified, randomized, double-blind, placebo-controlled study evaluating the efficacy of leuprolide acetate (LA) depot treatment before myomectomy. Stratification was based on pretreatment uterine volume (less than 600 cm3 versus greater than or equal to 600 cm3). Nine women received intramuscular (IM) depot LA 3.75 mg every 4 weeks for 12 weeks (group A); nine women received IM placebo with the same injection schedule (group B). All women underwent myomectomy within 4 weeks of their last injection. Mean total intraoperative blood loss was 213 +/- 44 mL (mean +/- standard error of the mean [SEM]) in group A and 302 +/- 43 mL in group B. When data from patients with large uteri (pretreatment uterine volumes of 600 cm3 or greater) were analyzed, mean total blood loss was 189 +/- 44 mL in group A and 390 +/- 20 mL in group B. These data suggest that leuprolide depot treatment before myomectomy may decrease intraoperative blood loss in women with large leiomyomata uteri.

Sonography of multiple gestations.

Ultrasound plays an important role in the management of multiple gestations in several key areas: (1) diagnosing multiple gestation and determining fetal number; (2) determining placentation; (3) diagnosing complications; (4) guiding procedures; and (5) identifying fetal lie late in pregnancy. The information obtained from single or serial ultrasound examinations can lead to improved obstetric decision-making and thereby to improved outcome in these high-risk pregnancies.

The superiority of sequential over simultaneous testing.

Diagnostic tests are typically used to help the physician select among available management options. When two or more tests are available, using them sequentially is potentially more efficient than simultaneously performing multiple tests, in that the former approach may allow the physician to perform fewer tests. In particular, we demonstrate that if two common conditions are met, any simultaneous strategy involving at least as many tests as management options can be replaced by a sequential strategy with the same outcome and a smaller expected number of tests. It follows that, in many clinical situations in which the benefits of performing fewer tests outweigh the costs that may result from delaying diagnosis, simultaneous strategies cannot be optimal. This result can decrease the number of diagnostic strategies that the physician or decision analyst needs to consider.

Testing for fetal pulmonary maturity: ROC analysis involving covariates, verification bias, and combination testing.

The lecithin/sphingomyelin ratio (L/S) and the measured value of saturated phosphatidylcholine (SPC), amniotic fluid determinations obtained to assess fetal pulmonary maturity, were evaluated with receiver operating characteristic (ROC) curve analysis. The effects of covariates on the ROC curves were analyzed with a regression methodology that took into account all the available data when constructing an ROC curve for each subgroup. To correct for verification bias the authors used a logistic regression analysis to model the probability of verification, thereby permitting correction for verification bias of a fully stratified data set in spite of small cell frequencies. They examined combination testing with prediction rules using prospective logistic modeling, including as variables test results and clinical features. The L/S was found to be significantly better than SPC for assessing fetal pulmonary maturity. For older gestational age the L/S and SPC performed better than for younger gestational age. Contamination of the specimen degraded the ROC curves. Correcting for verification bias did not influence the ROC curves significantly but changed the cutoff value of the test variable for any particular operating point. Prediction rules to evaluate combination testing showed that obtaining the SPC level in addition to the L/S ratio added no significant information compared with the L/S only. Including gestational age in the prediction rule of either test improved the prediction.

Duplex ultrasonography for persistent gestational trophoblastic tumor.

Duplex ultrasonography was performed on 17 consecutive patients being evaluated for persistent gestational trophoblastic tumor (GTT). All patients had had a prior molar pregnancy evacuated and presented with a rise or plateau in their beta-human chorionic gonadotropin levels. The ultrasonography was considered to be abnormal if the image demonstrated a focal area of altered echogenicity within the uterus or if Doppler scanning revealed a focal area of detectable intrauterine blood flow. The ultrasound findings were compared with the pathologic results from dilation and curettage specimens. Ten of the 17 patients had pathologically proven macroscopic tumor. Of those 10, 7 had an abnormal sonographic image (sensitivity, 70%), and 9 had an abnormal Doppler examination (sensitivity, 90%). In all 10 patients the image and/or Doppler examination was abnormal. Among four patients with microscopic disease, imaging was positive in one case, and the Doppler examination was positive in three. Imaging and Doppler ultrasonography are complementary modalities that can reliably detect persistent uterine GTT, and Doppler ultrasonography appears to be more sensitive than imaging in making this diagnosis.

Ultrasound guidance for selected dilatation and evacuation procedures.

Intraoperative ultrasound was used as an adjunct in difficult dilatation and evacuation (D&E) procedures for first-trimester abortions. This technique was useful in eight technically difficult D&Es in the presence of acute retroflexion, acute anteflexion, cervical stenosis and lower uterine segment fibroids.

Fetal growth disturbances.

IUGR is a fetal disorder characterized by diminished fetal growth, especially in the third trimester. Growth retardation may be due to primary placental insufficiency or may result from a variety of maternal or fetal causes and is associated with elevated perinatal mortality and morbidity. Numerous conventional and Doppler ultrasound criteria have been proposed for diagnosing IUGR prenatally, but none on its own permits confident diagnosis of this condition. Diagnosis or exclusion of IUGR can best be achieved by the combined use of three parameters: estimated fetal weight, amniotic fluid volume, and maternal hypertension. When IUGR is suspected based on these parameters, Doppler ultrasound can help to determine the prognosis. Large fetuses, particularly those weighing more than 4,000 grams at birth, are at risk for perinatal morbidity and mortality due to obstetrical complications. These fetuses occur more frequently and are at especially high risk in diabetic mothers. The estimated fetal weight is the most direct parameter for diagnosing LGA and macrosomia and is moderately accurate with positive predictive values up to 67% in the general population and 77% in diabetics. It can be an important factor in deciding on the route of delivery in diabetic mothers.

Statistical techniques for medical decision making: applications to diagnostic radiology.

The average radiologist will never compute a probability by using Bayes theorem or carry out a logistic regression, ROC, or cost-effectiveness analysis. Why, then, do we think that radiologists should be familiar with these techniques? Radiologists base many decisions on information gleaned from the published literature. In the past decade, the techniques discussed here have begun to appear in medical (including radiologic) publications. A radiologist with no comprehension of ROC analysis, for example, would be unable to critically assess a study that used this technique to compare MR imaging and CT in the detection of liver metastases and would have to accept or reject its conclusions blindly. A knowledgeable radiologist, on the other hand, could judge whether the study employed proper methodology, and could accept or reject its conclusions on that basis. The four cases presented here are specific examples of generic problems facing the radiologist: predicting the likelihood of disease on the basis of a test result, using several pieces of information provided by a single test to arrive at a diagnosis, comparing the efficacy of radiologic tests or interpretive techniques, and choosing among available tests or procedures on the basis of their relative cost-effectiveness. It is likely, therefore, that the techniques of medical decision making discussed here will appear with increasing frequency in the radiology literature. The list of potential applications is long. Some of the questions that can be addressed by the techniques presented here are: How predictive of IUGR are the various proposed Doppler criteria? How can they be used in conjunction with conventional sonographic criteria to diagnose IUGR? Which technique is best for detecting prostate cancer or for staging known cancer--sonography or MR imaging? Which MR pulse sequence is best for a variety of organ systems and clinical indications? Is routine screening obstetric sonography cost-effective? Applications of statistical decision-making techniques to these and related questions will improve the quality of health care provided by radiologists, if the statistical techniques are done properly and understood by the intended audience.

Improved prediction of gestational age from fetal head measurements.

Gestational age estimation based on biparietal diameter alone was compared with three approaches to age prediction that consider head shape: area-corrected biparietal diameter, circumference-corrected biparietal diameter, and head circumference. The analysis was based on 67 fetuses (13-41 weeks) in whom age was known with a high degree of accuracy, using a crown-rump length measurement from a prior first trimester sonographic examination. The three methods that consider head shape are more precise than biparietal diameter alone (p less than 0.05 for second trimester cases, less significantly demonstrated for third trimester cases). While the three appear to be equal to one another in accuracy, area correction may be the preferred approach based on theoretical grounds and on convenience. It is easy and can be used in conjunction with any formula (or table) now applied to biparietal diameter alone.

Sonographic evaluation of intrauterine growth retardation.

Intrauterine growth retardation (IUGR) may arise from a variety of causes, including placental insufficiency, maternal diseases, and fetal anomalies. Sonography plays a number of important roles in the diagnosis and management of growth retardation. Diagnosis of IUGR is based on fetal measurements, assessment of amniotic fluid volume, and other sonographic findings. Once IUGR has been diagnosed, sonography can help establish its cause. If a lethal cause is excluded, the fetus is monitored for the remainder of the pregnancy using sonography, including serial fetal measurements, biophysical profiles, and Doppler waveform indexes. Used appropriately, sonography can improve the outcome of fetuses with IUGR.