Is three-dimensional ultrasonography of additional value in the assessment of adnexal masses?

Reliability of preoperative evaluation of postmenopausal ovarian tumors

Background

Preoperative evaluation of ovarian tumors is challenging. This study was undertaken to evaluate the performance of conventional two-dimensional (2D) ultrasound and CA125 in predicting malignant or benign nature of pelvic masses, and to investigate if three-dimensional power Doppler (3DPD) ultrasound provides any added value. Ninety-six postmenopausal and four perimenopausal women with supposed ovarian tumors were examined by standardized 2D and 3DPD ultrasounds preoperatively. The tumors were evaluated using the risk of malignancy index (RMI), International Ovarian Tumors Analysis (IOTA) group simple rules, expert opinion, IOTA logistic regression model 2 (LR2) and 3D vascular indices, and were postoperatively compared to histopathological results.

Results

Ninety-eight tumors turned out to be ovarian in origin. Of these, 66 were benign and 32 malignant. RMI (cut-off value 200), simple rules, expert opinion and LR2 (cut-off value 25) were used to predict malignant nature of the tumors and had sensitivities of 71.9, 90.6, 87.5 and 90.6%, and specificities of 80.3, 84.6, 92.4 and 77.3%, respectively. When the 3D vascularization flow index (VFI) was added to RMI and LR2, the accuracy of the test improved from 77.6 to 81.4% and from 81.6 to 86.5%, respectively, at the expense of sensitivity, while VFI gave no added benefit for simple rules and expert opinion. Agreement between two examiners using expert opinion was good (Cohen’s kappa = 0.89).

Conclusions

The subjective opinion of an expert seems to be the most reliable method in assessing ovarian tumors, and the 3DPD indices seem to provide no significant added value.

The use of 3D power Doppler ultrasound in the quantification of blood vessels in uterine fibroids: feasibility and reproducibility

BACKGROUND

To evaluate the interobserver agreement and discriminating value of three-dimensional power Doppler ultrasound (3D PDUS) in patients with fibroids.

METHODS

An observational prospective cohort study in 19 patients with fibroids. 3D PDUS was performed by one examiner and evaluated by three independent examiners in order to evaluate various vascular parameters: vascular index (VI), flow index, and vascular flow index of the fibroid, the vascular capsule and of its highest vascular area, using both manual and automatic contour modes. The intraclass correlation coefficient and discriminating values were calculated. The correlation between VI and volume was studied using Kendall's Tau test.

RESULTS

In the manual contour mode, the VIs of the fibroid and of the vascular capsule had the highest interobserver agreements (intraclass correlation coefficients of 0.89 and 0.87, respectively). Both parameters seem to have good discriminating values, given the large range of these parameters between different fibroids, independent of their volume. The vascularity of the fibroid and capsule was related. VI was not related to the volume of the fibroid.

CONCLUSIONS

VI assessed using 3D PDUS is a reproducible parameter in the assessment of fibroid vascularization with discriminating abilities. Additional studies are needed to further evaluate its validity and clinical relevance.

Role of Three-Dimensional Ultrasound in Gynecology

Three-dimensional ultrasound (3D USG) is a fast-evolving imaging technique that holds a great potential for use in gynecology. Its sensitivity and specificity is reported to be close to 100 % for diagnosing congenital uterine anomalies, comparable with those of magnetic resonance imaging (MRI) and laparoscopy. With 3D USG, a coronal view of the uterus can be obtained, clearly outlining the external contour of the uterus and providing accurate information about the shape of the cavity. Although 3D USG may not perform well in thin endometria, combining it with saline infusion sonography (SIS) overcomes this problem. Research shows that 3D USG is more sensitive and specific than two-dimensional ultrasound (2D USG) in defining and mapping uterine lesions, such as fibroids, adenomyosis, and intrauterine synechia. In cases of suspected malignancy, 3D USG is mainly used in the initial evaluation of patients. Measuring various indices and mapping vascular architecture with 3D power Doppler have been proposed for evaluating adnexal masses. Although some studies raised hope, no consensus is reached about its use, success, and limitations. In urogynecology, translabial 3D USG is proved to be a valuable tool, as it provides instant access to the axial plane, which clearly depicts the relationship of the vagina, urethra, rectum, and the muscular pelvic floor. Studies report no significant differences between translabial 3D USG and MRI measurements for evaluation of the pelvic floor. In conclusion, adding 3D USG to routine gynecological workup can be beneficial for clinicians, as it provides fast and accurate results in a relatively cost-effective setting.

Screening for ovarian cancer in the general population

Advances in screening and early detection of ovarian cancer over the past decade have included novel interpretation of serum CA125, discovery of human epididymis protein 4, which has the potential to add to CA125, and the growing understanding of the flaws of previous biomarker studies. No mortality effect was found in the ovarian screening arm of the Prostate Lung Colorectal and Ovarian Cancer Screening Trial.(87) Concerns, however, have been raised about trial design, and the results from the UK Collaborative Trial of Ovarian Cancer Screening in the general population(38) and other ongoing studies in the high-risk population are awaited for a definitive conclusion. Future work needs to take into account the new insights into ovarian cancer subtypes and the growing evidence that a significant proportion of ovarian cancers might originate in premalignant lesions in the distal fallopian tube.

Management of the adnexal mass

Adnexal masses are commonly encountered in gynecologic practice and often present both diagnostic and management challenges. This is partly because of the fact that the majority of adnexal masses that are identified represent benign entities that do not necessarily require active intervention, yet a small subset will represent malignant processes that require both timely and appropriate surgical intervention for optimal outcome. To determine the best diagnostic and management strategies in this setting, physicians must effectively triage risk for malignancy by having a thorough understanding of the entities on the differential diagnosis and carefully considering the clinical context for each individual patient. Optimal selection and interpretation of diagnostic tests are enhanced by both an accurate clinical risk assessment and an understanding of the inherent accuracy of diagnostic tests considered in this setting. The purpose of this document is to provide clinicians with a practical strategy for distinguishing benign and malignant masses in the nonpregnant woman. Our approach addresses the critical elements of accurate risk stratification, reviews the performance of diagnostic tests for identifying malignancy, and offers evidence-based management algorithms to optimize outcomes for women with adnexal masses.

Does sphere volume affect the performance of three-dimensional power Doppler virtual vascular sampling for predicting malignancy in vascularized solid or cystic-solid adnexal masses?

OBJECTIVE

To assess whether, when using spherical sampling with Virtual Organ Computer-Aided Analysis (VOCAL) for calculating three-dimensional (3D) power Doppler angiography (PDA) indices, the sphere volume affects performance in the prediction of malignancy in vascularized cystic-solid or solid adnexal masses.

METHODS

One hundred and thirty-eight women (mean +/- SD age, 51.8 +/- 14.1 years) diagnosed as having vascularized cystic-solid or solid adnexal masses on B-mode and two-dimensional (2D) power Doppler ultrasound were evaluated by 3D-PDA prior to surgery. Five women had bilateral masses, giving a total number of 143 masses analyzed. Vascularization was assessed using VOCAL software. 3D-PDA vascular indices (vascularization index (VI), flow index (FI) and vascularization flow index (VFI)) from the most vascularized area within papillary projections and solid areas were calculated automatically using spherical sampling. Five different volumes of sphere were used (1 cm(3), 2 cm(3), 3 cm(3), 4 cm(3) and 5 cm(3)) in each case. A definitive histological diagnosis was obtained in each case after surgical tumor removal.

RESULTS

One hundred and seventeen (82%) masses were malignant and 26 (18%) were benign. Morphological evaluation revealed 34 (24%) unilocular solid masses, 49 (34%) multilocular solid masses and 60 (42%) mostly solid masses. The 1-cm(3) sphere could be used in 100% of the cases, the 2-cm(3) sphere could be used in 98.2% of the cases and the 3-5-cm(3) spheres could be used in 97.2% of the cases. The median VI, FI and VFI for all sphere volumes were significantly higher in malignant compared with non-malignant tumors. Receiver-operating characteristics curve analysis showed that VI and VFI, independently of sphere volume, were better predictors of malignancy than was FI. The best cut-off values for the 3D-PDA indices differed depending on sphere volume. VI was significantly more specific than were VFI and FI.

CONCLUSIONS

Sphere volume does not affect the performance of 3D-PDA. We recommend the use of different cut-off values for 3D-PDA indices for discriminating between benign and malignant adnexal masses, depending on the sphere volume used. Use of VI is preferable due to its higher specificity.

3D Ultrasound in Gynecology and Reproductive Medicine

With advances occurring in medicine on a daily basis, it was only a matter of time before essential gynecological investigations, such as ultrasound, were modified. Many clinicians remain unconvinced by its reputed advantages and 3D ultrasound is not without disadvantages. These mainly relate to the cost implications and training requirements. 3D ultrasound imaging is still at a relatively early stage in terms of its role as a day-to-day imaging modality in gynecology and reproductive medicine. 3D imaging has several obvious benefits that relate to an improved spatial orientation and the demonstration of multiplanar views, of which the coronal plane is particularly useful. It offers a more objective and reproducible measurement of volume and vascularity of the region of interest, and an improved assessment of normal and pathological pelvic organs through further postprocessing modalities, including tomographic ultrasound imaging and various rendering modalities. It also has the benefit of offering reduced scanning time, the option of teleconsultation and storage of images for re-evaluation. However, other than its application in the assessment and differentiation of uterine anomalies, there is very little evidence demonstrating that 3D ultrasound results in a clinically relevant benefit or negates the need for further investigation. Future work should ensure that 3D ultrasound is compared with conventional imaging in randomized trials where the observer is blind to the outcome, only after which will we truly be able to evaluate its role in an evidence-based manner.

Intraobserver and interobserver reproducibility of 3-dimensional power Doppler vascular indices in assessment of solid and cystic-solid adnexal masses

OBJECTIVE

The purpose of this study was to assess the intraobserver and interobserver reproducibility of 3-dimensional (3D) power Doppler angiography-derived vascular indices in evaluation of vascularized solid and cystic-solid adnexal masses.

METHODS

Stored 3D power Doppler angiographic volume data from 12 consecutive women with a diagnosis of a complex adnexal mass (6 cystic-solid and 6 solid) evaluated and treated at our institution were retrieved from our database for analysis. Two examiners performed the calculations blinded to each other. Calculations were performed offline in a computer using Virtual Organ Computer-Aided Analysis software (plane A, 9 degrees rotation step) to assess volume and vascularization (vascularization index, flow index, and vascularization-flow index) from solid areas within the tumor. In all cases, a definitive histologic diagnosis was obtained. Intraobserver and interobserver reproducibility was assessed by calculating the intraclass and interclass correlation coefficients for each index.

RESULTS

All tumors proved to be malignant after surgical removal. Intraobserver reproducibility for both examiners and interobserver reproducibility were high for all indices (interclass correlation coefficient > 0.95).

CONCLUSIONS

Three-dimensional power Doppler angiography is a reproducible technique for offline assessment of stored 3D volume data of vascularized adnexal masses.