Kinetics of a US contrast agent in benign and malignant adnexal tumors

Contrast-enhanced ultrasonography for differential diagnosis of adnexal masses

Background

Quantitative contrast-enhanced ultrasonography parameters are affected by various factors. We evaluated corrected quantitative contrast enhanced ultrasonography in differentiating benign adnexal tumors from malignant tumors.

Methods

Patients with adnexal masses who underwent conventional and contrast-enhanced ultrasonography were included. Contrast-enhanced ultrasonography parameters such as base intensity, arrival time, peak intensity, time to peak intensity, ascending slope, and descending slope were measured. Corrected (time to peak intensity − arrival time) _mass/(time to peak intensity − arrival time) _uterus and (peak intensity − base intensity) _mass/(peak intensity − base intensity) _uterus were calculated. Lesions were confirmed by pathologic examination of surgical specimens.

Results

This study included 31 patients with 35 adnexal lesions including 20 (57.10%) benign and 15 (42.90%) malignant lesions. The corrected contrast-enhanced ultrasonography quantitative parameters in lesions were statistically different between malignant and benign groups (P<0.05). The optimal cut-off value for (time to peak intensity − arrival time) _mass/(time to peak intensity − arrival time) _uterus, ascending slope, and (peak intensity − base intensity) _mass/(peak intensity − base intensity) _uterus, and descending slope for differentiating malignant adnexal masses from benign tumors were 1.05 (area under curve: 0.93, P<0.05), 1.11 (area under curve: 0.83, P<0.05), 0.82 (area under curve: 0.73, P<0.05), and −0.27 (area under curve: 0.66, P=0.16), with sensitivity and specificity of 93.33% and 85.00%, 86.67% and 75.00%, 86.67% and 60.00%, and 54.55% and 66.67%, respectively.

Conclusions

Corrected contrast-enhanced ultrasonography parameters provide practical differential diagnosis value of adnexal lesions with high reliability for sonologists.

A Study on Correlation between Contrast-Enhanced Ultrasound Parameters and Pathological Features of Diabetic Nephropathy

The objective of this study was to evaluate the correlation between contrast-enhanced ultrasound (CEUS) parameters and histopathological features in patients with diabetic nephropathy (DN). Sixty-two patients with DN (44 men, mean age: 52.61 ± 10.63 y) were enrolled. They underwent renal biopsy for DN at the Department of Ultrasound, PLA Hospital, between May 2017 and February 2020. Renal tissue was obtained by ultrasound-guided percutaneous needle biopsy. CEUS was performed, and time-intensity curves (TICs) and renal perfusion parameters were analyzed. Differences in CEUS parameters were analyzed according to the glomerular classification and interstitial fibrosis-tubular atrophy (IFTA) score. Continuous variables were evaluated using the analysis of variance or Mann-Whitney U-test. Discontinuous variables were compared with the χ²-test. Spearman correlation analyses evaluated associations among quantitative ultrasound perfusion parameters and histopathological characteristics. Peak enhancement (PE), wash-in rate (WiR), wash-in perfusion index (WiPI) and wash-out rate (WoR) of the cortex, and their cortex/medulla ratios, decreased with increasing glomerular classification grade (p < 0.05). The fall time (FT) of the cortex, and their cortex/medulla ratios, increased with increasing glomerular classification grade (p < 0.05). There were no significant differences in the CEUS parameters for different IFTA scores. The perfusion volume-relevant parameters (such as PE, WiR and WiPI) had a negative correlation (p < 0.05), while the perfusion time-relevant parameters (such as RT and FT) had a positive correlation (p < 0.05), with the severity of glomerular lesions, glomerulosclerosis rate and number of Kimmelstiel-Wilson lesions. The CEUS parameters of the cortex could reflect pathological characteristics, especially changes in glomerular lesions.

Difference in Perfusion Parameters Between Gastric Cancer and Gastric Stromal Tumors: Evaluation With Oral Contrast Plus Contrast-Enhanced Ultrasonography

Objective: To explore the difference of perfusion parameters between gastric cancer (GC) and gastric stromal tumors (GSTs) by using oral contrast plus contrast-enhanced ultrasonography (OC+CEUS).

Methods: We retrospectively reviewed 149 patients with histologically confirmed gastric lesions (80 patients with GC and 69 patients with GST). OC+CEUS was performed in all patients in the GC group and the GST group before surgery. The cine loops of OC+CEUS of all cases were analyzed. The perfusion parameters including arrival time (AT), time to peak (TTP), basal intensity (BI), and peak intensity (PI) were obtained via a program designed for autotracking contrast quantification (ACQ). The between-group differences in these parameters were compared.

Results: According to time-intensity curve (TIC) analysis, high-risk GST had higher PI than low-risk GST (P < 0.05). GC had faster AT and higher PI than normal gastric wall (P < 0.05); GST had higher PI than normal gastric wall (P < 0.05). Furthermore, the GC group had faster AT and higher PI than the GST group (P < 0.05). In contrast, the difference in BI and peak time (TTP) between the groups was not significant (P > 0.05).

Conclusion: AT and PI differ significantly between the GC group and the GST group. As a new method, OC+CEUS has value for the differential diagnosis of GC and GST.

Characterization of Adnexal Masses Using Contrast-Enhanced Subharmonic Imaging: A Pilot Study

OBJECTIVES

This pilot study evaluated whether contrast-enhanced subharmonic imaging (SHI) could be used to characterize adnexal masses before surgical intervention.

METHODS

Ten women (with 12 lesions) scheduled for surgery of an ovarian mass underwent an SHI examination of their adnexal region using a modified LOGIQ E9 scanner (GE Healthcare, Waukesha, WI) with an endocavitary transducer, in which digital clips were acquired by pulse destruction-replenishment SHI across the lesions. Time-intensity curves were created offline to quantitatively evaluate SHI parameters (fractional tumor perfusion, peak contrast intensity, time to peak contrast enhancement, and area under the time-intensity curve), which were compared to pathologic characterizations of the lesions.

RESULTS

Of the 12 masses, 8 were benign, and 4 were malignant. A qualitative analysis of the SHI images by an experienced radiologist resulted in diagnostic accuracy of 70%, compared to 56% without contrast, whereas an inexperienced radiologist improved from 50% to 58% accuracy, demonstrating the benefit of SHI. A quantitative analysis of SHI parameters produced diagnostic accuracy as high as 81%. Peak contrast intensity was significantly greater in malignant than benign masses (mean ± SD, 0.109 ± 0.088 versus 0.046 ± 0.030 arbitrary units; P = .046). Malignant masses also showed significantly greater perfusion than benign masses (24.79% ± 25.34% versus 7.62% ± 6.50%; P = .045). When the radiologist reads were combined with the most predictive quantitative SHI parameter (percent perfusion), diagnostic accuracy improved to 84% for the experienced radiologist and 96% for the novice radiologist.

CONCLUSIONS

Results indicate that SHI for presurgical characterization of adnexal masses may improve the determination of malignancy and diagnostic accuracy, albeit based on a small sample size.

Application Value of Color Doppler Ultrasound and Ultrasound Contrast in the Differential Diagnosis of Ovarian tumor

Objective:

To study the value of color Doppler ultrasound and ultrasound contrast in differential diagnosis of ovarian tumors.

Methods:

Ninety-six patients with ovarian tumors who were treated in our hospital from May 2017 to July 2018 and confirmed by pathological examination were selected as the research subjects. All patients were examined by color Doppler ultrasound and ultrasound contrast. The sensitivity, specificity and accuracy of the two methods were compared, and the parameters of ultrasound contrast in the diagnosis of benign and malignant tumors were observed and compared.

Results:

The sensitivity, specificity and accuracy of ultrasound contrast in the diagnosis of ovarian tumors were higher than those of color Doppler ultrasound (P<0.05). There were significant differences in the time of initiation enhancement, time to peak and perfusion intensity in the diagnosis of benign and malignant lesions by ultrasound contrast (P<0.05).

Conclusion:

In the differential diagnosis of ovarian tumors, ultrasound contrast has more advantages than color Doppler ultrasound in displaying the blood perfusion information of tumors. It has high diagnostic accuracy and clinical application value.

A preliminary study: The sequential use of the risk malignancy index and contrast-enhanced ultrasonography in differential diagnosis of adnexal masses

The aim of this study was to explore the sequential use of risk malignancy index (RMI) combined with contrast-enhanced ultrasonography (CEUS) in identification diagnosis of adnexal masses.This study contained 2 steps: first, 151 patients were analyzed retrospectively with RMI 1, RMI 2, and RMI 3 indices; receiver operating characteristic (ROC) curves were plotted to analyze area under the curves (AUC), and then RMI cut-off value was obtained according to maximum Youden index (YI, Sensitivity + Specificity - 1) and calculating diagnostic sensitivity, specificity, positive/negative predictive value, and accuracy. Second, 151 cases were divided into 2 groups randomly (105 in study group and 46 in test group); in the study group, the lower cut-off value (LC), upper cut-off value (UC), CEUS cut-off value according to maximum YI, and then these cut-offs were validated in test group.There was no statistical significance in 3 RMI models (P = .35), and RMI1 model was established randomly for following study. When the RMI1 cut-off value was 149, the YI was maximal (0.53), and the sensitivity, specificity, positive/negative predictive value, and accuracy were 71.0%, 81.7%, 77.1%, 75.6%, and 76.2%, respectively. The LC was 15 (sensitivity was 98.0%), the UC was 3000 (specificity was 98.0%), and the CEUS cut-off value was 7 (maximal YI was 0.81). In the test group (46 cases), combining RMI1 LC (15) and UC (3000) with CEUS cut-off value (7), the sensitivity, specificity, positive/negative predictive value, and accuracy were up to 85.7%, 92.0%, 90.0%, 88.5%, and 89.1%, respectively.CEUS can help RMI to make a more effective differential diagnosis of the adnexal mass. Further validation by additional multicenter prospective trials is required.

Screening for ovarian cancer: imaging challenges and opportunities for improvement

The United Kingdom Collaborative Trial of Ovarian Cancer Screening (UKCTOCS) recently reported a reduction in the average overall mortality among ovarian cancer patients screened with an annual sequential, multimodal strategy that tracked biomarker CA125 over time, where increasing serum CA125 levels prompted ultrasound. However, multiple cases were documented wherein serum CA125 levels were rising, but ultrasound screens were normal, thus delaying surgical intervention. A significant factor which could contribute to false negatives is that many aggressive ovarian cancers are believed to arise from epithelial cells on the fimbriae of the fallopian tubes, which are not readily imaged. Moreover, because only a fraction of metastatic tumors may reach a sonographically-detectable size before they metastasize, annual screening with ultrasound may fail to detect a large fraction of early-stage ovarian cancers. The ability to detect ovarian carcinomas before they metastasize is critical and future efforts towards improving screening should focus on identifying unique features specific to aggressive, early-stage tumors, as well as improving imaging sensitivity to allow for detection of tubal lesions. Implementation of a three-stage multimodal screening strategy in which a third modality is employed in cases where the first-line blood-based assay is positive and the second-line ultrasound exam is negative may also prove fruitful in detecting early-stage cases missed by ultrasound.

An evaluation of the clinical diagnostic value of contrast-enhanced ultrasound combined with contrast-enhanced computed tomography in space-occupying lesions of the kidney

BACKGROUND

There are a variety of space-occupying lesions of the kidney, and the benign lesions may be difficult to differentiate from the malignant ones. Therefore, an accurate judgment of the benign and malignant nature of the space-occupying lesions of the kidney is of high importance for the treatment and prognosis of these patients.

OBJECTIVE

To evaluate the diagnostic value of contrast-enhanced ultrasound (CEUS) combined with contrast-enhanced computed tomography (CECT) in space-occupying lesions of the kidney.

DATA AND METHODS

Three hundred and sixty-seven patients with space-occupying lesions of the kidney (378 lesions) were examined by CEUS and CECT, respectively, then, a combined diagnosis was made after the combination of CEUS and CECT by a multidisciplinary team. The diagnoses from the three methods were compared. The pathological results were taken as the gold standard. The sensitivity, specificity, positive and negative predictive values and area under the receiver operating characteristic (ROC) curve were calculated for the three methods. Thus, the diagnostic value of the three methods was assessed.

RESULTS

Of the 378 lesions examined, there were 301 malignant lesions and 77 benign lesions. The combined examination revealed 303 malignant lesions, with 9 benign lesions mistakenly diagnosed as malignant ones; thus, the misdiagnosis rate was 11.7%. By using the combined examination, 75 benign lesions were diagnosed, with the missed diagnosis of 7 malignant lesions, so the missed diagnosis rate was 2.3%. The sensitivity, specificity, positive and negative predictive values and area under the ROC curve with the combined examination of CEUS and CECT were 97.67% (0.950-0.989), 88.31% (0.785-0.942), 97.03% (0.942-0.985), 90.67% (0.811-0.958) and 0.930 (0.887-0.973), respectively. As compared with either CEUS or CECT alone, the difference in these indicators was of statistical significance (P<0.05). The combined examination greatly improved the sensitivity, specificity and accuracy of the diagnosis of the space-occupying lesions of the kidney.

CONCLUSION

CEUS and CECT each have advantages and disadvantages in the diagnosis of the space-occupying lesions of the kidney. The two techniques can be used in combination to compensate for the respective defects. More salient benefits can be reaped from the combined examination than from either technique used alone.

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.

Parametric mapping of contrasted ovarian transvaginal sonography

The purpose of this study was to assess the accuracy of parametric analysis of transvaginal contrast-enhanced ultrasound (TV-CEUS) for distinguishing benign versus malignant ovarian masses. A total of 48 ovarian masses (37 benign and 11 borderline/malignant) were examined with TV-CEUS (Definity; Lantheus, North Billerica, MA; Philips iU22; Philips Medical Systems, Bothell, WA). Parametric images were created offline with a quantification software (Bracco Suisse SA, Geneva, Switzerland) with map color scales adjusted such that abnormal hemodynamics were represented by the color red and the presence of any red color could be used to differentiate benign and malignant tumors. Using these map color scales, low values of the perfusion parameter were coded in blue, and intermediate values of the perfusion parameter were coded in yellow. Additionally, for each individual color (red, blue, or yellow), a darker shade of that color indicated a higher intensity value. Our study found that the parametric mapping method was considerably more sensitive than standard region of interest (ROI) analysis for the detection of malignant tumors but was also less specific than standard ROI analysis. Parametric mapping allows for stricter cutoff criteria, as hemodynamics are visualized on a finer scale than ROI analyses, and as such, parametric maps are a useful addition to TV-CEUS analysis by allowing ROIs to be limited to areas of the highest malignant potential.

Role of contrast-enhanced ultrasound (CEUS) in the diagnosis of endometrial pathology

Ultrasound is the reference imaging procedure used for the exploration of endometrial pathology. As medical procedures improve and the requirements of modern medicine become more demanding, gray-scale ultrasound is insufficient in establishing gynecological diagnosis. Thus, more complex examination techniques are required: Doppler ultrasound, contrast-enhanced ultrasound (CEUS), 3D ultrasound, etc. Contrast-enhanced ultrasound is a special examination technique that gains more and more ground. This allows a detailed real-time evaluation of microcirculation in a certain territory, which is impossible to perform by Doppler ultrasound. The aim of this review is to synthesize current knowledge regarding CEUS applications in endometrial pathology, to detail the technical aspects of endometrial CEUS and the physical properties of the equipment and contrast agents used, as well as to identify the limitations of the method.

Differentiating between benign and malignant adnexal lesions with contrast-enhanced transvaginal ultrasonography

OBJECTIVE

To analyze the relationship between contrast kinetics in tumorous vessels and lesion histologic type in an attempt to differentiate between malignant and benign disease.

METHODS

In a single-center prospective study, patients who had been referred for elective surgery because of a diagnosis of unilateral and/or bilateral adnexal masses were enrolled at Dr Jan Biziel University Hospital, Bydgoszcz, Poland, between January 2012 and September 2013. Participants underwent contrast-enhanced ultrasonography examination (CEUS). Contrast kinetics were obtained and compared with the neovascularization of the tumor. Accuracy, and positive and negative predictive values were calculated.

RESULTS

Among 160 enrolled patients, 84 underwent CEUS examination and 51 lesions were studied. Baseline and maximum color Doppler intensities were significantly higher in malignant than in benign tumors (P < 0.001 for both). Similarly, the absolute and relative increases in color Doppler intensity were significantly higher in malignant tumors (P < 0.001). The estimated positive predictive value was 97.1%, the negative predictive value was 100%, and the accuracy was 100%. Peak enhanced intensity of fractional color Doppler Area and area under the time-intensity curve (S-parameter) correlated significantly with the histology of the lesion (P < 0.001). Probability curves demonstrated that higher S-parameter values were correlated with a higher risk of malignancy.

CONCLUSION

Transvaginal CEUS is a reliable and reproducible way to differentiate between benign and malignant adnexal lesions.

Diagnostic performance of contrast-enhanced ultrasound for ovarian cancer: a meta-analysis

This meta-analysis is the first study aimed at assessing the overall diagnostic performance of contrast-enhanced ultrasound for ovarian cancer. PubMed, Embase and Medline databases were systematically searched for relevant articles published up to June 2014. Data were pooled to yield summary sensitivity, specificity, diagnostic odds ratio and receiver operating characteristic curves using Meta-Disc Version 1.4 software. Ten independent studies with 579 ovarian tumors were enrolled in this meta-analysis. The pooled sensitivity, specificity and diagnostic odds ratio statistics were 0.89 (0.83-0.94), 0.91 (0.88-0.93) and 91.70 (41.41-203.05), respectively, and the area under the summary receiver operating characteristic curve was 0.9619 (standard error: 0.0125), all indicating that contrast-enhanced ultrasound has high diagnostic accuracy in differentiation of malignant from benign ovarian tumors.

Dynamic contrast-enhanced ultrasound for quantification of tissue perfusion

Dynamic contrast-enhanced ultrasound (US) imaging, a technique that uses microbubble contrast agents with diagnostic US, has recently been technically summarized and reviewed by a European Federation of Societies for Ultrasound in Medicine and Biology position paper. However, the practical applications of this imaging technique were not included. This article reviews and discusses the published literature on the clinical use of dynamic contrast-enhanced US. This review finds that dynamic contrast-enhanced US imaging is the most sensitive cross-sectional real-time method for measuring the perfusion of parenchymatous organs noninvasively. It can measure parenchymal perfusion and therefore can differentiate between benign and malignant tumors. The most important routine clinical role of dynamic contrast-enhanced US is the prediction of tumor responses to chemotherapy within a very short time, shorter than using Response Evaluation Criteria in Solid Tumors criteria. Other applications found include quantifying the hepatic transit time, diabetic kidneys, transplant grafts, and Crohn disease. In addition, the problems involved in using dynamic contrast-enhanced US are discussed.

The contribution of qualitative CEUS to the determination of malignancy in adnexal masses, indeterminate on conventional US - a multicenter study

The aim of this study is to evaluate the efficacy of qualitative analysis of contrast-enhanced ultrasound (CEUS) in discrimination of adnexal masses which were undetermined by conventional ultrasound (US). A total of 120 patients underwent transabdominal CEUS. The initial enhancement time and intensity compared with the uterine myometrium, contrast agent distribution patterns and dynamic changes of enhancement were assessed. The sensitivity (Sen), specificity (Spe), positive predictive value (PPV), negative predictive value (NPV), accuracy (ACC) and Youden’s index were calculated for contrast variables. The gold standard was the histological diagnosis. There were 48 malignant tumors and 72 benign tumors. The enhancement features of malignant masses were different from benign ones. Earlier or simultaneous enhancement with inhomogeneous enhancement yielded the highest capability in differential diagnosis, and Sen, Spe, PPV, NPV, ACC, Youden’s index was 89.6%, 97.2%, 93.2%, 95.6%, 93.3%, and 0.88, respectively. The qualitative evaluation of CEUS is useful in the differential diagnosis of adnexal masses where conventional US is indeterminate.

Can contrast-enhanced ultrasound distinguish malignant from reactive lymph nodes in patients with head and neck cancers?

The purpose of this study was to investigate the utility of contrast-enhanced ultrasound in differentiating benign from malignant cervical lymph nodes in patients with squamous cell carcinoma of the head and neck. A consecutive series of 17 patients with known head and neck malignancy scheduled for neck surgery and lymph node clearance were recruited for contrast-enhanced ultrasound evaluation. Sonographic signal intensity as a function of time, comparing features of time to peak, time to arrival and time to wash-out, was quantified. The selected node was removed surgically and submitted for histology. Contrast-enhanced ultrasound examination had 100% sensitivity and 85.7% specificity for lymph node involvement. Functional analysis revealed contrast peaks significantly earlier in the malignant nodes (mean ± standard deviation) of 24.14 ± 2.7 s compared with 29.33 ± 3.4 s (p = 0.0128). Contrast-enhanced ultrasound holds promise in the detection and characterization of metastatic nodes that would not be diagnosed as abnormal on the basis of conventional ultrasound criteria.

The value and limitations of contrast-enhanced transrectal ultrasonography for the detection of prostate cancer

OBJECTIVES

To evaluate the role of contrast-enhanced transrectal ultrasonography (CE-TRUS) for detecting prostate carcinoma.

METHODS

Sixty-five patients with elevated serum prostate-specific antigen (PSA) and/or abnormal digital rectal examination (DRE) were assessed using transrectal ultrasound (TRUS) and CE-TRUS. In all the patients, CE-TRUS was performed with intravenous injection of contrast agent (SonoVue, 2.4 ml) before biopsy. The cancer detection rates of the two techniques were compared. False-positive and false-negative findings related to CE-TRUS were analyzed in comparison to the pathological results of biopsy or radical prostatectomy. The targeted biopsy to abnormal CE-TRUS areas was also compared to systematic biopsy.

RESULTS

Prostate cancer was detected in 29 of the 65 patients. CE-TRUS showed rapid focal enhancement or asymmetric vessels of peripheral zones in 28 patients; 23 of them had prostate cancer. CE-TRUS had 79.3% sensitivity, compared to 65.5% of TRUS (P<0.05). There were five false-positive and six false-negative findings from CE-TRUS. Benign prostate hyperplasia, and acute and chronic prostatitis were important causes related to the false-positive results of CE-TRUS. Prostate cancer originating from the transition zone or peripheral zone with lower PSA levels, small-size foci, and moderately or well-differentiated tumor was missed by CE-TRUS. The cancer detection rate of targeted biopsy (75%, 33/44 cores) was significantly higher than one of systematic biopsy (48.2%, 162/336) in those 28 cases (P<0.05). In addition, no significant correlation was found between the cancer detection rate with CE-TRUS and serum PSA levels.

CONCLUSION

CE-TRUS may improve the detection rate of prostate cancer through targeted biopsy of contrast-enhanced abnormalities. Our findings indicate that systematic biopsies should not be eliminated on the basis of false-positive and false-negative findings related to CE-TRUS.

Automated three-dimensional coded contrast imaging hysterosalpingo-contrast sonography: feasibility in office tubal patency testing

OBJECTIVE

To evaluate the feasibility of transvaginal hysterosalpingo-contrast sonography (HyCoSy) with new automated three-dimensional coded contrast imaging (3D-CCI) software in the evaluation of tubal patency and visualization of tubal course.

METHODS

Patients undergoing HyCoSy with automated 3D-CCI software were evaluated prospectively. First, to evaluate the feasibility of 3D visualization of tubal course, we performed consecutive volume acquisitions while injecting SonoVue contrast agent. We then performed conventional two-dimensional (2D) real-time HyCoSy to confirm tubal patency status by detection of saline and air bubbles moving through the Fallopian tubes and around the ovaries. We also evaluated visualization with CCI of the contrast agent around the ovaries, side effects and pain during and after the procedure, by visual analog scale (VAS) (ranging from 0 to 10, with 0 corresponding to no pain and 10 corresponding to maximum pain).

RESULTS

A total of 126 patients (252 tubes) underwent 3D-CCI HyCoSy followed by 2D real-time HyCoSy. According to the final 2D real-time evaluation, bilateral tubal patency was observed in 111 patients, bilateral tubal occlusion in four patients and unilateral tubal patency in 11 patients. The concordance rate for tubal patency status between the first 3D volume acquisition and the final 2D real-time evaluation was 84% and that between the second 3D volume acquisition and the final 2D real-time evaluation was 97%. A pain score >5 on VAS was recorded in 58% of patients during the procedure, but a pain score ≤ 5 was recorded in 85.7% of patients immediately after the procedure.

CONCLUSIONS

HyCoSy with automated 3D-CCI technology retains the advantages of conventional 2D HyCoSy while overcoming the disadvantages. 2D HyCoSy is highly observer-dependent and is only accurate in the hands of experienced investigators; by obtaining a volume of the uterus and tubes, automated 3D volume acquisition permits visualization of the tubes in the coronal view and of the tubal course in 3D space, and should allow less experienced operators to evaluate tubal patency status relatively easily.

Early detection of ovarian cancer with conventional and contrast-enhanced transvaginal sonography: recent advances and potential improvements

Recently, there have been several major technical advances in the sonographic diagnosis of ovarian cancer in its early stages. These include improved assessment of tumor morphology with transvaginal sonography (TVS), and detection and characterization of tumor neovascularity with transvaginal color Doppler sonography (TV-CDS) and contrast-enhanced transvaginal sonography (CE-TVS). This paper will discuss and illustrate these improvements and describe how they enhance detection of early-stage ovarian cancer. Our initial experience with parametric mapping of CE-TVS will also be mentioned.

Imaging of endometrial carcinoma using contrast-enhanced sonography

OBJECTIVES

The purpose of this study was to evaluate the utility of contrast-enhanced sonography as an adjunct to conventional transvaginal sonography for detecting endometrial carcinoma and defining the depth of myometrial invasion.

METHODS

A total of 35 patients with endometrial carcinoma diagnosed by endometrial sampling were examined with transvaginal sonography followed by contrast-enhanced sonography before treatment. The contrast enhancement phases (ie, early wash-in/out and late wash-in/out) were visually observed before comparison of tumors grouped by average diameter and histopathologic grade. We evaluated the effectiveness of contrast-enhanced sonography as an adjunct to transvaginal sonography in tumor imaging. We calculated the accuracy of contrast-enhanced sonography for diagnosing the depth of tumor invasion into the myometrium by using arcuate vascular plexus involvement as the sonographic standard for diagnosis of deep myometrial infiltration.

RESULTS

Of the 34 tumors identified by contrast-enhanced sonography, 28 (82.4%) showed early wash-in, and 6 (17.6%) showed late wash-in. Similar numbers of cases showed early and late wash-out. The enhancement phases did not differ significantly across groups with different average tumor diameters or histologic grades (P > .05). Contrast-enhanced sonography contributed the most to tumor imaging in patients with a thin endometrium after endometrial biopsy because it enhanced the contrast between the tumor and tissue. The diagnostic accuracy of contrast-enhanced sonography for determining the myometrium infiltration depth was 85.3%.

CONCLUSIONS

This study revealed diagnostically useful characteristics of the enhancement phase of endometrial carcinoma. The ability to enhance tumor-to-tissue contrast makes contrast-enhanced sonography a valuable adjunct to conventional sonography of endometrial carcinoma, especially for the thin endometrium found after endometrial biopsy. Contrast-enhanced sonography performed well in the diagnosis of the myometrial infiltration depth when using arcuate vascular plexus involvement as a marker of deep myometrial infiltration.

Histologic, molecular, and cytogenetic features of ovarian cancers: implications for diagnosis and treatment

Ovarian epithelial carcinoma (OEC), the most common ovarian malignancy, is a heterogeneous disease with several histologic subtypes that show characteristic cytogenetic features, molecular signatures, oncologic signaling pathways, and clinical-biologic behavior. Recent advances in histopathology and cytogenetics have provided insights into pathophysiologic features and natural history of OECs. Several studies have shown that high- or low-grade serous, endometrioid, and clear cell carcinomas are characterized by mutations involving the TP53, K-ras/BRAF, CTNNB1, and PIK3CA genes, respectively. High-grade serous carcinomas, the most common subtype, often manifest with early transcoelomic spread of disease beyond the ovaries, whereas low-grade serous and mucinous carcinomas commonly manifest with early-stage disease, with a resultant excellent prognosis. On the basis of pathogenetic mechanisms, recent findings suggest a dualistic model of ovarian carcinogenesis consisting of types I and II. Type I (low-grade serous, mucinous, and endometrioid) cancers commonly arise from well-described, genetically stable precursor lesions (usually borderline tumors); manifest as large adnexal masses with early-stage disease; and have a relatively indolent clinical course, with an overall good prognosis. In contrast, type II carcinomas (high-grade serous, endometrioid, mixed, and undifferentiated variants) originate de novo from the adnexal epithelia, often demonstrate chromosomal instability, and have aggressive biologic behavior. Better knowledge of hereditary ovarian cancer syndromes and associated cytogenetic abnormalities has led to increased interest in novel biomarkers and molecular therapeutics. Genetic changes, pathologic features, imaging findings, and natural histories of a variety of histologic subtypes of OEC are discussed in this article.

Radiological assessment of gynecologic malignancies

Patients with gynecologic malignancies are evaluated with a combination of imaging modalities including ultrasonography (US), computed tomography (CT), and magnetic resonance (MR) imaging. US has a primary role in detecting and characterizing endometrial and adnexal pathology. CT is one of the primary modalities in staging malignancy and detecting recurrence. MR imaging is characterized by superior contrast resolution and specificity. This article reviews the role of radiologic imaging for the characterization of gynecologic masses and for staging, planning, and monitoring treatment, as well as for the assessment of tumor recurrence of the most common gynecologic malignancies.

Study on the characteristics of contrast-enhanced ultrasound and its utility in assessing the microvessel density in ovarian tumors or tumor-like lesions

Angiogenesis is a critical factor in tumor growth and metastasis, and microvessel density (MVD) was an important parameter for assessing vessels in tumors. However, radiologic assessment of tumor vascularity is not yet well established. In our study, we aimed at investigating the efficacy of contrast-enhanced ultrasonography (CEUS) in exploring the vascularity of the ovarian tumors or tumor-like lesions to assess the relationship between the parameters of the peak intensity (PI) and area under curve (AUC) on CEUS and MVD in ovarian masses. Compared to the contrast-enhanced ultrasound technique, conventional ultrasound shows limitation in differentiating benign and malignant ovarian tumors. The former is promising in improving the sensitivity of detecting small vessels and blood flow in ovarian tumors. Our results showed clear differences in enhancement patterns between benign and malignant ovary tumors or tumor-like lesions. The PI and AUC in the malignant tumors were significantly higher than those in the benign tumors or tumor-like lesions (p=0.001 and =0.01, respectively). The MVD was 43.1 ± 20.4 in the benign tumors or tumor-like lesions and was 65.3 ± 22.3 in the malignant ones (p= 0.01). In both the benign and malignant groups, the PI and AUC were correlated significantly with the MVD (r=0.595, p = 0.001; r =0.533, p = 0.003, respectively). The PI and AUC in CEUS can reflect the MVD in ovarin tumors. The PI and AUC of the ovarian masses in the contrast transvaginal sonography show significant correlation with the angiogenesis and may help in assessing tumor vascularity in ovarian masses.

Contrast-enhanced sonography depicts spontaneous ovarian cancer at early stages in a preclinical animal model

OBJECTIVE

Our goal was to examine the feasibility of using laying hens, a preclinical model of human spontaneous ovarian cancer, in determining the kinetics of an ultrasound contrast agent indicative of ovarian tumor-associated neoangiogenesis in early-stage ovarian cancer.

METHODS

Three-year-old White Leghorn laying hens with decreased ovarian function were scanned before and after intravenous injection of a human serum albumin-perflutren contrast agent at a dose of 5 μL/kg body weight. Gray scale morphologic characteristics, Doppler indices, the arrival time, peak intensity, and wash-out of the contrast agent were recorded and archived on still images and video clips. Hens were euthanized thereafter; sonographic predictions were compared at gross examination; and ovarian tissues were collected. Archived clips were analyzed to determine contrast parameters and Doppler intensities of vessels. A time-intensity curve per hen was drawn, and the area under the curve was derived. Tumor types and the density of ovarian microvessels were determined by histologic examination and immunohistochemistry and compared to sonographic predictions.

RESULTS

The contrast agent significantly (P < .05) enhanced the visualization of microvessels, which was confirmed by immunohistochemistry. Contrast parameters, including the time of wash-out and area under the curve, were significantly different (P < .05) between ovaries of normal hens and hens with ovarian cancer and correctly detected cancer at earlier stages than the time of peak intensity.

CONCLUSIONS

The laying hen may be a useful animal model for determining ovarian tumor-associated vascular kinetics diagnostic of early-stage ovarian cancer using a contrast agent. This model may also be useful for testing the efficacy of different contrast agents in a preclinical setting.

Imaging of the ovine corpus luteum microcirculation with contrast ultrasound

Ultrasound contrast agents have been the subject of microvascular imaging research. The sheep corpus luteum (CL) is a microvascular tissue that provides a natural angiogenic and antiangiogenic process, which changes during the luteal phase of the estrous cycle of the ewe. It can also be controlled and monitored endocrinologically, providing a very attractive in vivo model for the study and development of microvascular measurement. The perfusion of the fully developed CL between days 8 and 12 of the estrous cycle was studied in six ewes. A Philips iU22 ultrasound scanner (Bothell, WA, USA) with the linear array probe L9-3 was used to capture contrast-enhanced images after an intravenous bolus injection of 2.4 mL SonoVue (Bracco S.P.A., Milan, Italy). Time-intensity curves of a region of interest inside the CL were formed from linearized image data. A lagged-normal model to simulate the compartmental kinetics of the microvascular flow was used to fit the data, and the wash-in time was measured. Good contrast enhancement was observed in the CLs of all animals and the wash-in time averaged at 5.5 s with 9% uncertainty. The regression coefficient was highly significant for all fits. These data correlated with stained endothelial area in the histology performed postmortem. Two ewes were injected with prostaglandin F2alpha to induce CL regression, which resulted in an increase of wash-in time after a few hours. The CL of the ewe is thus proposed as an ideal model for the study and development of microvascular measurements using contrast ultrasound. Our initial results demonstrate a highly reproducible model for the study of the microvascular hemodynamics in a range of tissues and organs.

Preoperative diagnosis of ovarian tumors using pelvic contrast-enhanced sonography

OBJECTIVE

The purpose of this study was to assess the feasibility of using a contrast agent for the sonographic examination of adnexal tumors and identify discriminating parameters in the preoperative diagnosis of malignant tumors.

METHODS

We conducted a prospective descriptive monocenter study that analyzed validated echographic criteria and parameters of the enhancement curve obtained by sonographic contrast agent injection. Patients included were referred for a second opinion after the discovery of a suspicious ovarian image. The final diagnosis was reached after surgery and an anatomopathologic examination.

RESULTS

Fifty-two tumors were analyzed. Morphologic and Doppler criteria analyses were conducted as described in the literature. The significant parameters of the enhancement curve were the time-intensity curve total area and the duration of activity of the contrast agent during the first phase of decay (P < .002). The performance of the contrast agent was lower than that of the examiner's subjective diagnosis, with an area under the receiver operating characteristic curve (AUC) of 0.78 versus 0.80. When borderline tumors were eliminated, there was an inversion of this, with an AUC of 0.85 versus 0.73. The inclusion of contrast results in the examiner's diagnosis in the context of a bivariate model comparing malignant and borderline tumors with benign tumors provided an AUC of 0.88.

CONCLUSIONS

Contrast-enhanced sonography improves preoperative diagnosis of ovarian tumors parameters. The significant parameters of the enhancement curve were significantly different for malignant and benign tumors. Borderline tumors contribute to a reduction of the discriminating capacity of the contrast agent.

New frontiers for ovarian cancer risk evaluation: proteomics and contrast-enhanced ultrasound

OBJECTIVE

The grim ovarian cancer statistics are attributed to the fact that most women typically present with widespread disease at the time of initial diagnosis. Our current diagnostic tools, such as pelvic examination and standard ultrasound, are inadequate to detect early-stage epithelial ovarian cancer. In recent years there has been an explosion of important advances in biomedical engineering, proteomic technologies, and computational analyses that has led to the identification of hundreds of previously unknown proteins unique to the pathophysiology of ovarian cancer, some of which are currently under clinical validation. At present, no one biomarker exists with 100% specificity and sensitivity for the accurate detection of early-stage epithelial ovarian cancer.

CONCLUSION

As the search for a panel of biomarkers detecting cancer, let alone early-stage disease, progresses, diagnostic imaging will continue to play a critical role to confirm or refute these biomarker assays. Interestingly, recent studies using contrast-enhanced ultrasound have shown potential as an early-detection tool by detecting the aberrant vascularity required for tumor growth before the development of a mass. Thus, we propose that the use of proteomic-based biomarker discovery and contrast-enhanced ultrasound may serve as a promising combination to help accurately identify early-stage epithelial ovarian cancer to improve women's health care.

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.

Intravenous contrast ultrasound examination using contrast-tuned imaging (CnTI) and the contrast medium SonoVue for discrimination between benign and malignant adnexal masses with solid components

OBJECTIVE

To determine whether intravenous contrast ultrasound examination is superior to gray-scale or power Doppler ultrasound for discrimination between benign and malignant adnexal masses with complex ultrasound morphology.

METHODS

In an international multicenter study, 134 patients with an ovarian mass with solid components or a multilocular cyst with more than 10 cyst locules, underwent a standardized transvaginal ultrasound examination followed by contrast examination using the contrast-tuned imaging technique and intravenous injection of the contrast medium SonoVue(R). Time intensity curves were constructed, and peak intensity, area under the intensity curve, time to peak, sharpness and half wash-out time were calculated. The sensitivity and specificity with regard to malignancy were calculated and receiver-operating characteristics (ROC) curves were drawn for gray-scale, power Doppler and contrast variables and for pattern recognition (subjective assignment of a certainly benign, probably benign, uncertain or malignant diagnosis, using gray-scale and power Doppler ultrasound findings). The gold standard was the histological diagnosis of the surgically removed tumors.

RESULTS

After exclusions (surgical removal of the mass > 3 months after the ultrasound examination, technical problems), 72 adnexal masses with solid components were used in our statistical analyses. The values for peak contrast signal intensity and area under the contrast signal intensity curve in malignant tumors were significantly higher than those in borderline tumors and benign tumors, while those for the benign and borderline tumors were similar. The area under the ROC curve of the best contrast variable with regard to diagnosing borderline or invasive malignancy (0.84) was larger than that of the best gray-scale (0.75) and power Doppler ultrasound variable (0.79) but smaller than that of pattern recognition (0.93).

CONCLUSION

Findings on ultrasound contrast examination differed between benign and malignant tumors but there was a substantial overlap in contrast findings between benign and borderline tumors. It appears that ultrasound contrast examination is not superior to conventional ultrasound techniques, which also have difficulty in distinguishing between benign and borderline tumors, but can easily differentiate invasive malignancies from other tumors.

Diagnostic value of contrast-enhanced ultrasonography in the characterization of ovarian tumors()

INTRODUCTION

Vascularity influences the characteristics of gynecologic tumors observed with direct imaging techniques that reveal the macrovascular component of these lesions (color and power Doppler) and with indirect imaging involving the administration of contrast agents to examine the microcirculation and interstitial perfusion (contrast-enhanced computed tomography [CT] and magnetic resonance [MR] imaging). The purpose of this study was to determine whether contrast-enhanced ultrasonography (CEUS) of ovarian lesions provides useful information that cannot be obtained with conventional US.

MATERIALS AND METHODS

We used CEUS to assess 72 nonspecific adnexal lesions in 61 patients. CEUS was performed with a 4.8-ml bolus of a second-generation ultrasonographic contrast agent and dedicated imaging algorithms. For each lesion, B-mode morphology, CEUS morphology, and time/intensity curves were evaluated.

RESULTS

In 8/61 cases (13.1%) CEUS offered no additional morphovascular information. In 38/61 cases (62.3%), it provided additional information that did not modify the management of the lesion, and in 15/61 cases (24.6%) it gave additional information that modified the management of the lesion. Malignant lesions were characterized by significantly shorter times to peak enhancement (11.9 ± 3.1 s vs 19.8 ± 4.0 s p < 0.01) and significantly higher peak intensity (24.7 ± 4.2 dB vs 17.8 ± 3.3 dB p < 0.01) compared with benign lesions.

CONCLUSIONS

CEUS improves diagnostic confidence in the characterization of liquid-corpuscular lesions where conventional US is inconclusive. CEUS can be proposed as a valid alternative to CT and MR. However, information obtained by CEUS influences the therapy in a limited percentage of cases (24.6%).

Diagnostic parameters to differentiate benign from malignant ovarian masses with contrast-enhanced transvaginal sonography

OBJECTIVE

The aim of this study was to evaluate diagnostic parameters to differentiate between benign versus malignant ovarian masses using contrast-enhanced transvaginal sonography (TVS).

METHODS

Thirty-three consecutive patients with 36 morphologically abnormal ovarian masses (solid or cystic with papillary excrescences, focally thickened walls, or irregular solid areas) smaller than 10 cm received a microbubble contrast agent intravenously while undergoing pulse inversion harmonic TVS. The following parameters were assessed: presence of contrast enhancement, time to peak enhancement, peak contrast enhancement, half wash-out time, and area under the enhancement curve (AUC). Tumor histologic analysis was used to distinguish benign from malignant ovarian tumors.

RESULTS

Twenty-six benign masses and 10 malignancies were studied. Of all examined criteria, an AUC of greater than 787 seconds(-1) was the most accurate diagnostic criterion for ovarian cancer, with 100.0% sensitivity and 96.2% specificity. Additionally, peak contrast enhancement of greater than 17.2 dB (90.0% sensitivity and 98.3% specificity) and half wash-out time of greater than 41.0 seconds (100.0% sensitivity and 92.3% specificity) proved to be useful.

CONCLUSIONS

Our data suggest that the AUC, peak enhancement, and half wash-out time had the greatest diagnostic accuracy for contrast-enhanced TVS in differentiation between benign and malignant ovarian masses.

Contrast-enhanced transvaginal sonography of benign versus malignant ovarian masses: preliminary findings

OBJECTIVE

The aim of this prospective study was to evaluate differences in contrast enhancement and contrast enhancement kinetics in benign versus malignant ovarian masses with pulse inversion harmonic transvaginal sonography.

METHODS

Seventeen consecutive patients with 23 morphologically abnormal ovarian masses (solid or cystic with papillary excrescences, focally thickened walls, or irregular solid areas) smaller than 10 cm received a microbubble contrast agent intravenously while undergoing pulse inversion harmonic transvaginal sonography. The following parameters were assessed in all tumors: detectable contrast enhancement, time to peak enhancement (wash-in), peak contrast enhancement, half wash-out time, and area under the enhancement curve. Tumor histologic analysis was used to distinguish benign from malignant ovarian tumors.

RESULTS

Fourteen benign masses and 9 malignancies were studied. There was a statistically significant difference in the peak enhancement (mean +/- SD, 23.3 +/- 2.8 versus 12.3 +/- 3.9 dB; P < .01), half wash-out time (139.9 +/- 43.6 versus 46.3 +/- 19.7 seconds; P < .01), and area under the enhancement curve (2012.9 +/- 532.9 versus 523.9 +/- 318 seconds(-1); P < .01) in malignant masses compared with benign disease. There was no statistically significant difference in the time to peak enhancement (26.1 +/- 6.3 versus 24.9 +/- 7.6 seconds; P = .07).

CONCLUSIONS

Overall, our data showed a significant difference in the contrast enhancement kinetic parameters between benign and malignant ovarian masses.

Detection of ovarian tumors in chicken by sonography: a step toward early diagnosis in humans?

OBJECTIVE

Animal models of spontaneous ovarian cancer are important for understanding early tumor development. Ovarian imaging may play an important role in following changes in tumor development. Laying hens are the only animals that develop spontaneous ovarian cancer similar to humans. The aim of this study was to determine the feasibility of detecting ovarian tumors in laying hens using sonography.

METHODS

Ovaries of commercial strains of White Leghorn laying hens (n = 29, 2.5-3.0 years old) were examined by transvaginal 2-dimensional gray scale and color Doppler sonography. Sonographic evaluations were compared with ovarian anatomy and histologic features.

RESULTS

Results of in vivo sonography and ovarian anatomic and histologic examinations were consistent. The presence of gross ovarian tumors was correctly detected in all hens by sonography. The resistive and pulsatility index values associated with ovarian tumors were lower than for normal ovaries (P < .001) suggesting that blood flow velocity was increased in ovarian tumors. Values associated with abnormal ovarian histologic findings but no gross tumors were intermediate.

CONCLUSIONS

Transvaginal sonography can be used to determine ovarian status in hens. It offers the ability to make repeated examinations on the same hen to monitor early changes in the ovary associated with ovarian cancer.

Ultrasonography, computed tomography and magnetic resonance imaging for diagnosis of ovarian carcinoma

Our objective was to compare US, CT, and MR imaging in differentiation of malignant from benign ovarian tumors. Through an electronic literature search and manual review of bibliographies (January 1990 to June 2006), relevant studies on the diagnostic performance of US, CT, and MR imaging in the differentiation between benign and malignant ovarian tumours were identified. Sixty-nine articles were included, yielding 143 studies. Data on the accuracy of the different imaging modalities were analyzed and compared by constructing summary receiver-operating characteristic (ROC) curves. Our results suggest that US techniques seems to be similar with CT and MRI in differentiation of malignant from benign ovarian tumors. The results also revealed that color Doppler flow imaging alone is significantly inferior to combined US techniques, morphologic assessment alone and contrast enhanced US in diagnosis of ovarian cancer. In conclusion, US morphologic assessment still is the most important and common modality in detect ovarian cancer.

MR imaging compared with intraoperative frozen-section examination for the diagnosis of adnexal tumors; correlation with final histology

The aim was to compare the accuracy of magnetic resonance imaging (MRI) and intraoperative consultation (IC) for the diagnosis of adnexal masses, with reference to final histology. MRI was performed in 136 women with sonographically indeterminate adnexal masses. IC included macroscopic and frozen-section examination. Macroscopic examination and MRI determined size, nature, and presence of vegetations or solid portions within masses. All masses were characterized as benign or malignant according to previously published MR imaging and histopathologic criteria. Sensitivities, specificities, and predictive values for the diagnosis of malignancy of MRI and IC were assessed. Histology revealed 168 adnexal masses (99 benign, 23 borderline and 46 invasive). Frozen sections were examined in 151 cases. Among the 151 adnexal masses studied by both MRI and IC, respective sensitivities, specificities, positive and predictive values of both methods for the diagnosis of malignancy were 89.7% and 84.5%, 91.4% and 100%, 86.7% and 100%, and 93.4% and 91.3%. Sensitivities of MR imaging and frozen section for the diagnosis of serous versus mucinous borderline tumors were 33.3% and 93.3%, and 62.5% and 12.5%, respectively. MRI is less accurate than IC for characterizing adnexal masses. However, MRI may increase the relevance of IC for borderline mucinous tumors.

Assessment of cyclic changes of microvessels in ovine ovaries using Sonovue contrast-enhanced ultrasound

Our objective was to detect variations of ovarian vascularization that occur in the estrus cycle of the ewe using an IV contrast agent. Five ewes were investigated using contrast-enhanced power Doppler after Sonovue injection at day 0, 3, 5, 10 and 13 of the cycle in two successive estrus cycles. Transvaginal ultrasound monitoring of each ewe was performed after a dose of Sonovue. Parameters derived from the time-intensity curves were compared. Quantification of the enhancement and wash-in period parameters changed significantly between ovaries and between the follicular and luteal periods of the cycle. Uptake time, wash-out time, total time of enhancement and area under the curve were the parameters with the smallest variation between ovaries. Wash-out time and area under the curve are two contrast parameters that did not change with cyclic changes. Thus, using these parameters in premenopausal women will allow more accurate detection of vascular modifications that may be associated with ovarian cancer.

Blood flow remodels growing vasculature during vascular endothelial growth factor gene therapy and determines between capillary arterialization and sprouting angiogenesis

BACKGROUND

For clinically relevant proangiogenic therapy, it would be essential that the growth of the whole vascular tree is promoted. Vascular endothelial growth factor (VEGF) is well known to induce angiogenesis, but its capability to promote growth of larger vessels is controversial. We hypothesized that blood flow remodels vascular growth during VEGF gene therapy and may contribute to the growth of large vessels.

METHODS AND RESULTS

Adenoviral (Ad) VEGF or LacZ control gene transfer was performed in rabbit hindlimb semimembranous muscles with or without ligation of the profound femoral artery (PFA). Contrast-enhanced ultrasound and dynamic susceptibility contrast MRI demonstrated dramatic 23- to 27-fold increases in perfusion index and a strong decrease in peripheral resistance 6 days after AdVEGF gene transfer in normal muscles. Enlargement by 20-fold, increased pericyte coverage, and decreased alkaline phosphatase and dipeptidyl peptidase IV activities suggested the transformation of capillaries toward an arterial phenotype. Increase in muscle perfusion was attenuated, and blood vessel growth was more variable, showing more sprouting angiogenesis and formation of blood lacunae after AdVEGF gene transfer in muscles with ligated PFA than in normal muscles. Three-dimensional ultrasound reconstructions and histology showed that the whole vascular tree, including large arteries and veins, was enlarged manifold by AdVEGF. Blood flow was normalized and enlarged collaterals persisted in operated limbs 14 days after AdVEGF treatment.

CONCLUSIONS

This study shows that (1) blood flow modulates vessel growth during VEGF gene therapy and (2) VEGF overexpression promotes growth of arteries and veins and induces capillary arterialization leading to supraphysiological blood flow in target muscles.