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.

Accuracy of nuchal translucency measurement depends on equipment used and its calibration.

OBJECTIVES: To determine the effect of different ultrasound machine-probe combinations on nuchal translucency (NT) measurements and to assess how this impacts on the accuracy of the NT-derived component of first-trimester screening for trisomy 21. METHODS: Sixteen different ultrasound machine-probe combinations were used for axial measurement of 2.0-, 3.0- and 4.0-mm spaced targets in an ultrasound phantom. Differences between the measured and known values were determined. The mean of the axial measurements was used to calculate adjusted risks for trisomy 21, given specific clinical scenarios. RESULTS: Differences observed using different machine-probe combinations for the 2.0-mm target ranged from 1.8-2.2 mm; for the 3.0-mm target, 2.7-3.2 mm; and for the 4-mm target, 3.7-4.3 mm, and exceeded those due to intraobserver variability. For a fetal crown-rump length of 50.0 mm and NT measurement of 2.0 mm, the maximum/minimum measurements in the fetus of a 40-year-old woman led to derived risks ranging from 1 in 32 (NT, 2.2 mm) to 1 in 189 (NT, 1.8 mm) and in the fetus of a 20-year-old with an NT of 3.0 mm these ranged from 1 in 102 (NT, 3.2 mm) to 1 in 160 (NT, 2.7 mm). CONCLUSIONS: We have described the effect of machine-probe combinations on small but very precise ultrasound measurements. Such machine-probe combinations led to greater variability than those ascribed to intraobserver differences, and significantly affected the screening risk for the same fixed measurement. This finding has implications for Down syndrome screening algorithms and audit of ultrasound operators. Furthermore, most ultrasound machines are neither calibrated nor specified for measurements of tenths of a mm.

Clinical implications of machine-probe combinations on obstetric ultrasound measurements used in pregnancy dating.

OBJECTIVE: To investigate the effect of use of different machine-probe combinations on measurement variability and to assess how this variability impacts on accuracy of pregnancy dating. METHODS: Sixteen different ultrasound machine-probe combinations were used for lateral measurement of targets spaced 10 and 40 mm apart and axial measurement of targets spaced 10 and 50 mm apart in an ultrasound phantom, and differences between the measured and true values were determined. The mean of the 40-mm lateral measurements was used to estimate gestational age using standard obstetric dating tables for crown-rump length (CRL) and femur length (FL) and the mean of the 50-mm axial measurements was used to estimate gestational age using the obstetric dating tables for biparietal diameter (BPD). RESULTS: As absolute measurements became larger, differences observed using different machine-probe combinations exceeded those due to intraobserver variability. Maximum dating differences for first-trimester CRL of 2 days (based on a measured CRL range of 39-42 mm), second-trimester BPD of 4 days (based on a measured BPD range of 49-52 mm) and FL of 9 days (based on a measured FL range of 39-42 mm) were observed when measurements were transposed to the equivalent gestational age using standard charts. CONCLUSION: Differences between measured and true values of biometric measurements reflect both machine-probe and intraobserver variability. Incremental first-trimester CRL growth with time is rapid, but second-trimester FL growth is much less so, leaving this lateral measurement more prone to both observer and machine-probe errors. The only axial growth measurement commonly performed is BPD where the measurement differences were intermediate between those of CRL and FL. The differences that can be ascribed to different equipment combinations are in many cases greater than those expected in clinical practice and are of potential importance in determining how fetal biometry is used for dating pregnancies.

Mild pyelectasis.

Mild pyelectasis is a common finding which is often incidental, with no significant long term sequelae. However, there is a small association with aneuploidy and postnatal renal pathology. In this paper the aetiology and prognosis are discussed and the management strategies described.