Assessment of ovarian reserve using the inversion mode

3D and 4D studies from human reproduction to perinatal medicine

Three-dimensional ultrasound (3D US) is a modality of choice for prenatal diagnosis of congenital malformations. But 3D-four-dimensional US(4D US) is of utmost importance also to achieve pregnancy. 3D US plays an important role for diagnosis of PCO, to assess ovarian reserve and response and thus to decide optimum stimulation protocols. It adds to the information on follicular maturity and endometrial receptivity, thus improving the chances to achieve pregnancy for patients under treatment for fertility. 3D hystero-contrast-salpingography (HyCoSy) has also proved itself to be one of the best modalities for assessment of tubal patency. In this article, the role of 3D and 4D US is discussed for the following. I. Pretreatment assessment of the females desiring fertility which includes assessment of uterus and fallopian tubes. II. Monitoring of infertile females undergoing treatment. III. Assessment of very early pregnancy - especially in abnormal locations.

The cohort of antral follicles measuring 2-6 mm reflects the quantitative status of ovarian reserve as assessed by serum levels of anti-Müllerian hormone and response to controlled ovarian stimulation

OBJECTIVE

To evaluate the relationship between serum anti-Müllerian hormone (AMH) and antral follicle size, and to ascertain which cohort of antral follicles is most predictive of the response to controlled ovarian stimulation during assisted reproduction treatment (ART).

DESIGN

Prospective study.

SETTING

University-based Assisted Conception Unit.

PATIENT(S)

One hundred thirteen women undergoing first cycle of ART.

INTERVENTION(S)

Transvaginal 3D-ultrasound assessment and venipuncture in the early-follicular phase of the menstrual cycle.

MAIN OUTCOME MEASURE(S)

Serum AMH levels, number of mature oocytes retrieved and poor ovarian response.

RESULT(S)

The antral follicle cohorts measuring 2 to 3 mm, >3 to 4 mm, >4 to 5 mm, and >5 to 6 mm were most significantly correlated with AMH (r = .30, .27, .30, and .41, respectively) and the number of mature oocytes retrieved (r = .28, .23, .29, and .34, respectively). Although these follicle cohorts of 2-6 mm were significant predictors of the number of mature oocytes retrieved on regression analysis, their discriminative ability (area under the curve [AUC]: 0.829) for the prediction of poor ovarian response was similar to total counts made using cohorts of 2 to 4 mm, 2 to 5 mm, 2 to 8 mm, and 2 to 10 mm (AUCs: 0.794, 0.812, 0.852, and 0.826, respectively).

CONCLUSION(S)

The number of antral follicles measuring 2 to 6 mm is most reflective of the quantitative ovarian reserve. However, the ability of this group of antral follicles to predict poor ovarian response appears similar to that of the follicular cohorts of 2 to 4 mm, 2 to 5 mm, 2 to 8 mm, and 2 to 10 mm.

Three-dimensional ultrasound improves the interobserver reliability of antral follicle counts and facilitates increased clinical work flow

OBJECTIVES

To compare the interobserver reliability of antral follicle counts made using real-time two-dimensional (2D) ultrasound with offline counts made from stored three-dimensional (3D) data and to assess the time required for such counts.

METHODS

Two observers conducted transvaginal ultrasound examinations in 45 subfertile women in the early follicular phase of the menstrual cycle. Antral follicles were counted using real-time 2D ultrasound and the time taken was recorded. A 3D volume was then acquired from each ovary and stored for subsequent offline analysis using the multiplanar view. The time taken for each step was recorded and the total time was calculated. Intraclass correlation coefficients (ICC) and limits of agreement were used to assess reliability.

RESULTS

There was no difference in the mean antral follicle counts using real-time 2D (16.51 +/- 11.51) and 3D (16.33 +/- 12.13) ultrasound. According to ICCs, there was a significantly higher interobserver reliability for counts made using 3D (mean, 0.992; 95% CI, 0.986-0.996) compared with real-time 2D (mean, 0.961; 95% CI, 0.940-0.977) (P < 0.01) ultrasound. 3D ultrasound was also associated with narrower limits of agreement (-2.7 to + 3.1) than was 2D ultrasound (-6.9 to + 6.4). Whilst the total time taken was significantly longer for the 3D technique (239.3 +/- 71.4 s vs. 103.1 +/- 28.6 s, P < 0.001), the time required for the actual ultrasound examination was significantly less (46.4 +/- 7.4 s vs. 103.1 +/- 28.6 s, P < 0.001).

CONCLUSIONS

3D ultrasound significantly improves the interobserver reliability of antral follicle counts. While this is at the expense of time overall, the duration of the actual ultrasound examination and patient exposure is significantly reduced using 3D compared with real-time 2D ultrasound.

The interobserver reliability of off-line antral follicle counts made from stored three-dimensional ultrasound data: a comparative study of different measurement techniques

OBJECTIVE

To assess the interobserver reliability of antral follicle counts (AFCs) made from stored three-dimensional (3D) ultrasound data using conventional two-dimensional (2D) images, 3D multiplanar view and 3D-rendered 'inversion mode'.

METHODS

3D transvaginal ultrasound was performed in the early follicular phase (days 2-5) of the menstrual cycle in 41 subjects aged < 40 years, undergoing investigation for subfertility. From the stored 3D ultrasound datasets, the number of antral follicles of 2-10 mm in diameter in each ovary was independently measured, using all three methods by three investigators, each with a different level of experience. The image quality of each dataset was subjectively categorized into one of three groups, based on the proportion of the ovarian contour that could be seen clearly.

RESULTS

There was no significant difference in the mean AFC between the observers for any of the three different techniques. The intraclass correlation coefficient (ICC) for the 2D-equivalent mode, the 3D multiplanar mode, and the 3D-rendered inversion mode were indicative of good interobserver reliability for each method. The interobserver reliability for the 3D-rendered inversion mode was better with Grade 1 image quality than with Grade 3 image quality. There were no equivalent differences, however, between the three different grades of image quality with the 2D-equivalent and 3D multiplanar modes. The time taken for AFC measurement using 3D-rendered inversion mode was significantly longer than with the 2D equivalent and 3D multiplanar methods.

CONCLUSIONS

3D image displays and rendering techniques do not appear to offer any advantage over a conventional 2D display in terms of AFC measurement reliability. AFC measurement using the 3D-rendered inversion mode has an adequate interobserver reproducibility but is dependent on image quality.