Three-dimensional power Doppler vascular sonographic sampling for predicting ovarian cancer in cystic-solid and solid vascularized masses

ACR Appropriateness Criteria® Clinically Suspected Adnexal Mass, No Acute Symptoms

There are approximately 9.1 pelvic surgeries performed for every histologically confirmed adnexal malignancy in the United States, compared to 2.3 surgeries per malignancy (in oncology centers) and 5.9 surgeries per malignancy (in other centers) in Europe. An important prognostic factor in the long-term survival in patients with ovarian malignancy is the initial management by a gynecological oncologist. With high accuracy of imaging for adnexal mass characterization and consequent appropriate triage to subspecialty referral, the better use of gynecologic oncology can improve treatment outcomes. Ultrasound, including transabdominal, transvaginal, and duplex ultrasound, combined with MRI with contrast can diagnose adnexal masses as benign with specific features (ie, functional masses, dermoid, endometrioma, fibroma, pedunculated fibroid, hydrosalpinx, peritoneal inclusion cyst, Tarlov cyst), malignant, or indeterminate. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Combination of GI-RADS and 3D-CEUS for differential diagnosis of ovarian masses

OBJECTIVE

The purpose of this study is to evaluate the efficacy of the combination of gynecologic imaging reporting and data system (GI-RADS) ultrasonographic stratification and three-dimensional contrast-enhanced ultrasonography (3D-CEUS) in order to distinguish malignant from benign ovarian masses.

METHODS

In this study, 102 patients with ovarian masses were examined by both two-dimensional ultrasound(2D-US) and 3D-CEUS. Sonographic features of ovarian masses obtained from 3D-CEUS were analyzed and compared with 2D-US. All patients with ovarian masses were confirmed by operational pathology or long-term follow-up results.

RESULTS

(1)The Chi-square test and multiple Logistic regression analysis confirmed that there were only eight independent predictors of malignant masses, including thick septa (≥3mm), thick papillary projections(≥7mm), solid areas, presence of ascites, central vascularization, contrast enhancement, distribution of contrast agent, and vascular characteristics of the solid part and their odds ratios which were 5.52, 5.39, 4.94, 4.34, 5.92, 7.44, 6.09, and 7.67, respectively (P<0.05). (2)These eight signs were used to combine the GI-RADS with 3D-CEUS scoring system in which the corresponding value of the area under the curve (AUC) was 0.969, which was superior to using GI-RADS lonely (Z-value=1.64, P<0.025). Using 4 points as the cut-off, the scoring system showed the performance was clearly better than using GI-RADS alone (P<0.05). (3) The Kappa value was 0.872 for two different clinicians with equal experience.

CONCLUSIONS

The combination of GI-RADS and 3D-CEUS scoring system would be a more effective method to distinguish malignant from benign ovarian masses.

Three-Dimensional Power Doppler Vascularization in Women With Ovarian Endometriomas and Relationship With Associated Painful Symptoms

OBJECTIVES

The objective of the study was to evaluate the correlation between endometrioma-associated pain and lesion vascularization as measured with 3-dimensional power Doppler transvaginal sonography.

METHODS

Endometriomas were examined, and 4 indices were obtained: mean grayness, flow index, vascularization index, and vascularization-flow index. Dysmenorrhea, chronic pelvic pain, and dyspareunia were analyzed in terms of severity, presence/absence, and duration.

RESULTS

Twenty-nine women were selected. The univariable association of painful symptoms in terms of presence/absence and duration was low with the exception of mean grayness with the presence of chronic pelvic pain (β = -0.106; P = .047; 95% confidence interval, 0.810 to 0.998). The R² value increased to 0.226 for dysmenorrhea (β = -0.475; P = .029) when analyzing the association between the vascularization index and the severity of painful symptoms. The visual analog scale scores for chronic pelvic pain and dyspareunia were higher (R²  = 0.300; β = -0.547 and -0.548, respectively; P = .028 and .053).

CONCLUSIONS

We observed an inverse association between the severity of pain and endometrioma vascularization. Further larger studies are required to confirm our findings.

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.

Influence of Pulse Repetition Frequency on 3-D Power Doppler Quantification

Three-dimensional power Doppler quantification has limited application because of its high dependency on attenuation. The purpose of the study described here was to assess if different degrees of attenuation, depending on pulse repetition frequency (PRF) adjustment, alter 3-D power Doppler quantification in a region of 100% moving blood when using vascularization index, flow index and vascularization flow index (VFI). A cubic-shaped gelatin phantom with a 1.8-mm-internal-diameter silicon tube was used. The tube, placed at 45° to the phantom's surface, was filled with blood-mimicking fluid with as constant maximum velocity of 30 cm/s. Two different attenuation blocks (low and high attenuation) were alternatively placed between the phantom and the transvaginal transducer. One single observer acquired 10 data sets for each PRF level from 0.3 to 7.5 kHz, using the high- and low-attenuation blocks, for a total of 200 3-D power Doppler data sets. We assessed VFI from 1.5-mm-diameter spherical samples, virtually placed inside the tube, always at the same position. No difference was noted between high- and low-attenuation VFI values when using a PRF of 0.3 kHz. As PRF increased, it was observed that VFI quantification progressively differed between low and high attenuation. Also, a slope on VFI values for both high- and low-attenuation models could be observed when increasing PRF, particularly above 4.0 kHz. We concluded that PRF adjustment is very relevant when using VFI to quantify 3-D power Doppler signal.

Contrast-enhanced ultrasound for differential diagnosis of malignant and benign ovarian tumors: systematic review and meta-analysis

OBJECTIVE

To assess the performance of contrast-enhanced ultrasound (CE-US) in the differential diagnosis of malignant and benign ovarian tumors.

METHODS

We conducted a comprehensive literature search of PubMed and EMBASE to identify published articles evaluating the diagnostic potential of CE-US for the differentiation of benign and malignant ovarian tumors. Inclusion criteria were: (1) the study assessed the accuracy (or sensitivity and specificity) of CE-US for diagnosis of benign and malignant ovarian tumors; (2) it used surgery and histopathology as the reference standard for distinguishing between benign and malignant tumors; (3) it included data allowing construction of a 2×2 contingency table for true- and false-positives and negatives. We present summary sensitivity, specificity, diagnostic odds ratio (OR) and areas under the summary receiver-operating characteristics curves (AUCs).

RESULTS

Preliminary screening identified 103 papers, of which 11 fulfilled our predefined inclusion criteria and underwent final analysis. The pooled sensitivity and specificity of CE-US for diagnosis of benign and malignant ovarian tumors were 93% (95% CI, 89-96%) and 95% (95% CI, 92-96%), respectively. The pooled diagnostic OR was 171.2 (95% CI, 65.9-444.6) and the AUC was 0.98. I(2) values of sensitivity, specificity and diagnostic OR were 38.3%, 31.7% and 48.4%, respectively, all indicating moderate heterogeneity.

CONCLUSIONS

The evidence from available studies suggests CE-US is useful for discriminating between benign and malignant ovarian tumors; however, further studies are needed to examine whether CE-US has improved diagnostic test accuracy compared with that of standard two-dimensional Doppler sonography.

Past, present and future ultrasonographic techniques for analyzing ovarian masses

Ultrasonography is today the method of choice for distinguishing between benign and malignant adnexal pathologies. Using pattern recognition several types of tumors can be recognized according to their characteristic appearance on gray-scale imaging. Color Doppler imaging should be used only to perform a semiquantitative color score or evaluate the flow location. International Ovarian Tumor Analysis group had standardized definitions characterizing adnexal masses and suggested the use of 'simple rules' in premenopausal women. Recently, the use of 3D vascular indices has been proposed but its potential use in clinical practice is debated. Also computerized aided diagnosis algorithms showed encouraging results to be confirmed in the future.

Performance of three-dimensional power Doppler angiography as third-step assessment in differential diagnosis of adnexal masses

OBJECTIVE

To evaluate the contribution of three-dimensional (3D) power Doppler angiography (3D-PDA) to the differential diagnosis of adnexal masses.

METHODS

This was a prospective study in women diagnosed with a persistent adnexal mass and subsequently scheduled for surgery in a tertiary university hospital. All women were evaluated by transvaginal/transrectal ultrasound according to a predetermined three-step protocol, with transabdominal ultrasound being performed in some cases. First, morphological evaluation of the mass was performed using gray-scale 'pattern recognition' (first step). Lesions diagnosed as having a benign pattern were considered as being at low risk of malignancy whereas tumors with solid components, ascites and/or signs of carcinomatosis were considered as being at high risk of malignancy. In both cases no further test was performed and a decision regarding clinical management, either for follow-up or surgery, was taken. Tumors with solid components but without signs of ascites or carcinomatosis were considered as being at intermediate risk of malignancy. These lesions were assessed by two-dimensional (2D) PDA to evaluate tumor vascularity (color score) (second step). Solid tumors with a color score of 1 or 2 were considered as benign and no further test was performed, while tumors with a color score of 2, 3 or 4 within solid components or a color score of 3 or 4 in the case of a solid tumor were considered as malignant. The latter group underwent 3D-PDA assessment (third step). Vascularization index (VI) was calculated in a 1-mL sphere of the most vascularized area of the tumor. When a VI ≥ 24.015% was found, the tumor was considered as malignant. All masses were removed surgically and definitive histological diagnosis was used as the gold standard. Sensitivity and specificity for each strategy were calculated and compared. In the case of bilateral tumors, only the more suspicious one was used for analysis.

RESULTS

A total of 367 adnexal masses diagnosed in 367 women (mean age, 46.5 (range, 18-80) years) were evaluated during the study period. Of these, 86 masses were malignant and 281 were benign. The sensitivity and specificity for each assessment strategy were as follows: one-step, 97.7% and 78.6%; two-step, 94.2% and 97.9% (P < 0.001 for specificity when compared with that of one-step); three-step, 90.7% and 98.9% (not statistically significant when compared with that of two-step).

CONCLUSIONS

The addition of 2D-PDA in the differential diagnosis of an adnexal mass significantly increases specificity while sensitivity remains high; however performing subsequent 3D-PDA does not provide additional information or further improve diagnostic performance subsequent to 2D-PDA.

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.

[Sonographic diagnosis of presumed benign ovarian tumors]

To discriminate ovarian lesions is of particular importance in gynecological practice. Two main problems need answers: discrimination of benign and malignant adnexal masses and choice of the appropriate surgical treatment if necessary. Nearly 2% of the adnexal masses are ovarian carcinomas or borderline tumors. It is now, well established that ultrasonography is the gold standard for ovarian cyst diagnosis. The purpose of this data was to review the literature and to establish, with the evidence base medicine model, which parameters and existing diagnostic models using ultrasound and Doppler perform best in the evaluation of adnexal masses. Transvaginal sonography has demonstrated considerable advantage over conventional transabdominal sonography. However, transparietal sonography is still useful in large tumors. Definition of the nomenclature and classification was done and should be used. Unilocular ovarian cyst characterization seems easy using sonography and Doppler. In front of complication, discrimination of such functional cyst may be difficult but spontaneous regression confirms usually the expectative management. Dermoid cysts and endometriomas seem to be easier to discriminate from other adnexal masses. Ultrasound and morphologic parameters have a sensitivity of about 90% and a specificity of 80%; that makes this exam the gold standard for ovarian masses diagnosis. Only 50% of ovarian masses are characterized by sonography. Scoring systems help to differentiate benign from malignant masses (sensitivity of about 90%). Logistic regression and models are good methods especially for LR1 and 2 and RMI and may be useful for malignancy prediction but are difficult to use in current practice. Expert diagnosis is a subjective but most important performing parameter. Any suspicious ovarian mass or not easily diagnosed mass requires sonography by an expert, which can first use all the techniques and the different parameters to discriminate benign and malignant tumors. An explicit report will help the physician to define the right attitude for an appropriate management. Six to 16% of adnexial masses are complex or not classified and will result in MRI prescription or surgery.

The "volumetric" pulsatility index as evaluated by spatiotemporal imaging correlation (STIC): a preliminary description of a novel technique, its application to the endometrium and an evaluation of its reproducibility

We propose new volumetric indices derived from three-dimensional (3-D) power Doppler (PD) using spatiotemporal imaging correlation (STIC) to overcome the influence of machine settings and attenuation. In this study, we describe these indices and evaluate their interobserver reliability: two static-3-D and two STIC PD datasets were acquired from 60 women and two observers (blinded analysis) evaluated vascularization index (VI), the flow index (FI) and the vascularization flow index (VFI) of standardized spherical samples of endometrium. Three new indices were determined based on maximum, minimum and mean values (vPI, vRI(max-min), vS/D(max-min)) and two indices from frames subjectively defined as systole and diastole (vRI(sys-dia), vS/D(sys-dia)). Highest intraclass coefficient correlations (ICCs) were obtained from vPI derived from VI or VFI (0.77-0.76), followed by vRI(max-min) (0.72-0.72) and vS/D(max-min) (0.52-0.49). ICCs from indices based on subjectively systole and diastole or FI were consistently lower (<0.40). We conclude that the subjective choice of systolic and diastolic frames only lacks reliability but indices based on complete evaluation may reliably be used.

The role of 3-dimensional power Doppler imaging in the assessment of ovarian teratoma in pregnancy: a case report

Background. Conventional sonography is the primary imaging tool for these pregnant women who present with an ovarian teratoma. In some cases, however, sonography diagnosis is difficult. We report a case of ovarian teratoma during pregnancy diagnosed by three-dimensional Power Doppler. The cyst was removed via laparotomy without fetal or maternal complications. Three-dimensional ultrasound with multiplanar view can better discriminate a benign ovarian teratoma from complex ovarian lesions or malignant tumors. Its role is significant especially during pregnancy as it may assist in determining which patients are requiring surgery and which are not. The results of three-dimensional sonography and magnetic resonance (MR) were equal but the role of MR imaging is limited in early pregnancy. Conclusions. Three-dimensional technique is a reliable diagnostic modality for preoperative assessment of an ovarian teratoma as it can be performed during the first trimester of pregnancy.

Contribution of power Doppler blood flow mapping to gray-scale ultrasound for predicting malignancy of adnexal masses in symptomatic and asymptomatic women

OBJECTIVE

To determine the contribution of power Doppler blood flow mapping to gray-scale ultrasound for predicting malignancy of adnexal masses in symptomatic and asymptomatic women.

STUDY DESIGN

One thousand and ninety-four women with adnexal mass were included. Patients were divided into three groups according to clinical complaints: asymptomatic (group A), patients with symptoms non-suspicious of ovarian cancer (group B) and patients with symptoms suspicious of ovarian cancer (group C). All patients underwent transvaginal power Doppler ultrasound prior to surgery. Any mass in which the echo architecture at B-mode ultrasound was not highly suggestive of benign histology was categorized as questionable. In these cases power Doppler was performed as the second step. Definitive histological diagnosis was used as the standard reference. Sensitivity, specificity, positive likelihood ratio (+LR) and negative likelihood ratio (-LR) were calculated for B-mode diagnosis and B-mode plus Doppler in each group.

RESULTS

In group A, B-mode was significantly more sensitive (98.1%) than Doppler ultrasound (91.3%) (p<0.01). In group B Doppler ultrasound (97.0%) was more specific than B-mode ultrasound (92.2%) (p<0.001). In group C Doppler ultrasound (84.0%) was more specific than B-mode ultrasound (68.0%) (p<0.001). Positive LR was significantly higher after Doppler evaluation in all groups (30.5 vs 12.8 in group A, 33.2 vs 12.8 in group B and 6.0 vs 3.1 in group C).

CONCLUSIONS

The diagnostic performance of B-mode and power Doppler ultrasound is different depending on patients' complaints.

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.

Advances in sonographic detection of ovarian cancer: depiction of tumor neovascularity with microbubbles

OBJECTIVE

The purpose of this article is to discuss and illustrate the use of contrast-enhanced transvaginal sonography for the early detection of ovarian cancer and suggest how this technique may best be used to distinguish benign from malignant ovarian masses.

CONCLUSION

Microbubble-enhanced transvaginal sonography can enhance the evaluation of ovarian masses by early detection of tumor microvascularity.