Contrast-Enhanced Ultrasound Imaging of Uterine Disorders: A Systematic Review

Clinical signs and diagnosis of fibroids from adolescence to menopause

The aim of this review was to provide an updated assessment of the present diagnostic tools and clinical symptoms and signs to evaluate uterine fibroids (UFs) on the basis of current guidelines, recent scientific evidence, and a PubMed and Google Scholar search for peer-reviewed original and review articles related to clinical signs and diagnosis of UFs. Approximately 50%-75% of UFs are considered nonclinically relevant. When present, the most common symptoms are abnormal uterine bleeding, pelvic pain and/or bulk symptoms, and reproductive failure. Transvaginal ultrasound is recommended as the initial diagnostic modality because of its accessibility and high sensitivity, although magnetic resonance imaging appears to be the most accurate diagnostic tool to date in certain cases. Other emerging techniques, such as saline infusion sonohysterography, elastography, and contrast-enhanced ultrasonography, may contribute to improving diagnostic accuracy in selected cases. Moreover, artificial intelligence has begun to demonstrate its ability as a complementary tool to improve the efficiency of UF diagnosis. Therefore, it is critical to standardize descriptions of transvaginal ultrasound images according to updated classifications and to individualize the use of the different complementary diagnostic tools available to achieve precise uterine mapping that can lead to targeted therapeutic approaches according to the clinical context of each patient.

Diagnostic accuracy of MRI in the differential diagnosis between uterine leiomyomas and sarcomas: A systematic review and meta-analysis

BACKGROUND

Differential diagnosis between uterine leiomyomas and sarcomas is challenging. Magnetic resonance imaging (MRI) represents the second-line diagnostic method after ultrasound for the assessment of uterine masses.

OBJECTIVES

To assess the accuracy of MRI in the differential diagnosis between uterine leiomyomas and sarcomas.

SEARCH STRATEGY

A systematic review and meta-analysis was performed searching five electronic databases from their inception to June 2023.

SELECTION CRITERIA

All peer-reviewed observational or randomized clinical trials that reported an unbiased postoperative histologic diagnosis of uterine leiomyoma or uterine sarcoma, which also comprehended a preoperative MRI evaluation of the uterine mass.

DATA COLLECTION AND ANALYSIS

Sensitivity, specificity, positive and negative likelihood ratios, diagnostic odds ratio, and area under the curve on summary receiver operating characteristic of MRI in differentiating uterine leiomyomas and sarcomas were calculated as individual and pooled estimates, with 95% confidence intervals (CI).

RESULTS

Eight studies with 2495 women (2253 with uterine leiomyomas and 179 with uterine sarcomas), were included. MRI showed pooled sensitivity of 0.90 (95% CI 0.84-0.94), specificity of 0.96 (95% CI 0.96-0.97), positive likelihood ratio of 13.55 (95% CI 6.20-29.61), negative likelihood ratio of 0.08 (95% CI 0.02-0.32), diagnostic odds ratio of 175.13 (95% CI 46.53-659.09), and area under the curve of 0.9759.

CONCLUSIONS

MRI has a high diagnostic accuracy in the differential diagnosis between uterine leiomyomas and sarcomas.

Evaluation of Uterine Fibroid Vascularity Using Contrast-Enhanced Ultrasound in Comparison with Contrast-Enhanced Magnetic Resonance Imaging

OBJECTIVE

The aim of the work described here was to assess uterine fibroid vascularity using contrast-enhanced ultrasound (CEUS) as compared with magnetic resonance imaging (MRI).

METHODS

Forty women diagnosed with symptomatic uterine fibroids scheduled for uterine artery embolization (UAE) were enrolled in this institutional review board-approved study. Before UAE, participants underwent CEUS examination with an Aplio i800 scanner (Canon Medical Systems, Tustin, CA, USA) with curvilinear array (8C1). CEUS was performed using 2.0 mL of the ultrasound contrast agent Lumason (Bracco, Milan, Italy) administered intravenously. Digital CEUS clips were acquired and randomized offline, and fibroids were characterized as hyper- or hypovascular. MRI was used as reference standard for fibroid vascularity and compared with CEUS. Results were analyzed using McNemar's test.

RESULTS

Forty participants were enrolled in the trial. One patient did not proceed with the UAE procedure and one patient refused pre-procedure MRI because of claustrophobia. Therefore, 38 participants underwent CEUS and MRI examinations before UAE. Hypervascular fibroids were seen on MRI and CEUS in 24 and 26 participants, respectively. Hypovascular fibroids were seen with MRI and CEUS in 14 and 12 participants, respectively. Fibroids characterized as hypovascular in two participants by MRI were characterized as hypervascular by CEUS. CEUS and MRI findings were similar in 36 of 38 participants, corresponding to an accuracy of 95% (p = 0.62).

CONCLUSION

Contrast-enhanced ultrasound can accurately assess uterine fibroid vascularity, serving as a potential alternative to MRI in determination of the vascularity of uterine fibroids.

Preoperative multimodal ultrasonic imaging in a case of Peutz-Jeghers syndrome complicated by atypical lobular endocervical glandular hyperplasia: a case report and literature review

BACKGROUND

Peutz-Jeghers syndrome (PJS), an autosomal dominant multiple cancerous disorder, is clinically characterized by mucocutaneous macules and multiple gastrointestinal hamartomatous polyps. Gastric-type endocervical adenocarcinoma (G-EAC), a special subtype of cervical adenocarcinoma with non-specific symptoms and signs, is known to occur in approximately 11% of female patients with PJS.

CASE PRESENTATION

Here, we report a case of PJS in a 24-year-old female with multiple mucocutaneous black macules who complained of vaginal discharge and menorrhagia. Moreover, we first described the multimodal ultrasonographical manifestations of PJS-correlated G-EAC. The three-dimensional reconstructed view of G-EAC on 3D realisticVue exhibited a distinctive "cosmos pattern" resembling features on magnetic resonance imaging, and the contrast-enhanced ultrasound displayed a "quick-up and slow-down" pattern of the solid components inside the mixed cervical echoes. We reported the multimodal ultrasonographical characteristics of a case of PJS-related G-EAC, as well as reviewed PJS-related literature and medical imaging features and clinical characteristics of G-EAC to provide insight into the feasibility and potential of utilizing multimodal ultrasonography for the diagnosis of G-EAC.

CONCLUSIONS

Multimodal ultrasound can visualize morphological features, solid components inside, and blood supplies of the G-EAC lesion and distinguish the G-EAC lesion from normal adjacent tissues. This facilitates preoperative diagnosis and staging of PJS-related G-EAC, thereby aiding subsequent health and reproductive management for patients with PJS.

Diagnostic value of enhanced-contrast ultrasound for cesarean scar pregnancy: A systematic review

BACKGROUND

Cesarean scar pregnancy, an uncommon ectopic pregnancy in which the embryo is implanted in the cesarean scar, poses significant risks without prompt diagnosis and treatment. Its prevalence has risen alongside increased cesarean section rates. Despite various treatment approaches, consensus remains elusive. Ultrasonography, particularly contrast-enhanced ultrasonography, shows promise in cesarean scar pregnancy diagnosis.

MAIN BODY

This systematic review, following PRISMA guidelines, explores contrast-enhanced ultrasound's diagnostic potential in cesarean scar pregnancy. We searched PubMed, Scopus, Web of Science, and Google Scholar up to August 2023. Selection involved two stages: title/abstract screening and full-text assessment. The included studies investigated contrast-enhanced ultrasound's diagnostic value in cesarean scar pregnancy, provided adequate data, and were peer-reviewed in English. Quality assessment followed the QUADAS-2 criteria. We extracted the diagnostic accuracy metrics: sensitivity, specificity, and accuracy. Out of 193 records, five studies met the inclusion criteria (2016-2020, China). Contrast-enhanced ultrasound displayed sensitivities of 77%-100% and specificities of 95%-100%. Two studies reported accuracy of 96.9%-97.8%. Compared with conventional ultrasound, contrast-enhanced ultrasound exhibited superior sensitivity, specificity, and accuracy. It also outperformed transvaginal ultrasound.

CONCLUSION

Enhanced-contrast ultrasound holds promise for diagnosing and managing cesarean scar pregnancy by visualizing scar vascularization in real-time, thereby reducing severe complication risks. This review highlights contrast-enhanced ultrasound as a transformative diagnostic tool for cesarean scar pregnancy management, despite existing evidence limitations.

Diagnostic Accuracy of Ultrasound in the Diagnosis of Uterine Leiomyomas and Sarcomas

BACKGROUND

Differential diagnosis between uterine leiomyomas and sarcomas is challenging. Ultrasound shows an uncertain role in the clinical practice given that pooled estimates about its diagnostic accuracy are lacking.

OBJECTIVES

To assess the accuracy of ultrasound in the differential diagnosis between uterine leiomyomas and sarcomas.

DATA SOURCES

A systematic review was performed searching 5 electronic databases (MEDLINE, Web of Sciences, Google Scholar, Scopus, and ClinicalTrial.gov) from their inception to June 2023.

METHODS OF STUDY SELECTION

All peer-reviewed observational or randomized clinical trials that reported an unbiased postoperative histologic diagnosis of uterine leiomyoma or uterine sarcoma that also comprised a preoperative ultrasonographic evaluation of the uterine mass.

TABULATION, INTEGRATION, AND RESULTS

Sensitivity, specificity, positive and negative likelihood ratios, diagnostic odds ratio, and area under the curve on summary receiver operating characteristic were calculated for each included study and as pooled estimate, with 95% confidence interval (CI); 972 women (694 with uterine leiomyomas and 278 with uterine sarcomas) were included. Ultrasound showed pooled sensitivity of 0.76 (95% CI, 0.70-0.81), specificity of 0.89 (95% CI, 0.87-0.92), positive and negative likelihood ratios of 6.65 (95% CI, 4.45-9.93) and 0.26 (95% CI, 0.07-1.0) respectively, diagnostic odds ratio of 23.06 (95% CI, 4.56-116.53), and area under the curve of 0.8925.

CONCLUSIONS

Ultrasound seems to have only a moderate diagnostic accuracy in the differential diagnosis between uterine leiomyomas and sarcomas, with a lower sensitivity than specificity.

Value of contrast-enhanced ultrasonography in microwave ablation treatment of symptomatic focal uterine adenomyosis

PURPOSE

This study evaluated the value of contrast-enhanced ultrasonography (CEUS) in the ultrasound-guided microwave ablation (MWA) treatment of symptomatic focal uterine adenomyosis.

METHODS

This retrospective study was conducted between March 2020 and January 2023, enrolling 52 patients with symptomatic focal uterine adenomyosis who had undergone MWA. All patients were examined with CEUS before and after MWA. The non-perfused volume (NPV) was compared between CEUS and dynamic contrast-enhanced magnetic resonance imaging (DCEMRI) following ablation. Therapeutic efficacy and safety were evaluated at 3-, 6-, and 12-month follow-ups. Additionally, this study explored the correlations between pre-treatment CEUS features and a volume reduction ratio indicating sufficient ablation, defined as 50% or more at the 3-month follow-up.

RESULTS

No significant differences in NPV were noted between CEUS and DCE-MRI immediately after MWA and during follow-up (all P>0.05). At the 3-month follow-up, the median VRRs for the uterus and adenomyosis were 33.2% and 63.9%, respectively. Sufficient ablation was achieved in 69.2% (36/52) of adenomyosis cases, while partial ablation was observed in the remaining 30.8% (16/52). The identification of non-enhancing areas on pre-treatment CEUS was associated with sufficient ablation (P=0.016). At the 12-month follow-up, significant decreases were observed in both the uterine and adenomyosis volumes (all P<0.001). Dysmenorrhea and menorrhagia were significantly alleviated at 12 months, and no major complications were encountered.

CONCLUSION

CEUS can be used to evaluate the ablation zone of focal adenomyosis that has been treated with MWA, similarly to DCE-MRI. The identification of non-enhancing areas on pretreatment CEUS indicates satisfactory treatment outcomes.

Pancreatic metastasis of leiomyoma found 27 years after uterine fibroid surgery

A 59-year-old female was referred to our hospital for pancreatic tumor. She had undergone resection of uterine fibroids 27 years ago, and leiomyoma in the left thigh 8 years ago. Tumor markers were normal. A well-defined hypoechoic tumor measuring 26 mm × 22 mm was detected at the pancreatic tail using ultrasound. Inside the tumor, a small cystic structure was observed. High-sensitivity Doppler imaging revealed faint signals indicating blood flow from the periphery to the interior. Contrast-enhanced ultrasonography in the arterial phase revealed slow, heterogenous enhancement from the periphery to the center of the mass that occurred later than that in the pancreatic parenchyma. The tumor then exhibited homogeneous enhancement except for the periphery, with subsequent washout. Endoscopic ultrasound-fine-needle aspiration was performed. Histopathological examination diagnosed a leiomyoma. The left thigh tumor resected 8 years ago had been diagnosed as benign metastatic leiomyoma (BML). We considered that the current pancreatic tumor was also BML clinically. We report this case because pancreatic metastasis from uterine fibroids is extremely rare. Uterine fibroids are benign tumors, but there are rare cases of metastasis to various organs, which should be considered when performing ultrasound.

Clinical value of quantitative analysis of contrast-enhanced ultrasonography in the differential diagnosis of benign and malignant pelvic tumors

Background

Cervical cancer, endometrial cancer, and ovarian cancer are among the top 10 most common cancers in women, with ovarian cancer in particular being considered a "silent killer". Therefore, early detection, diagnosis, and treatment constitute important means of care for women's health. This study investigated the clinical value of the quantitative analysis of contrast-enhanced ultrasonography (CEUS) in the differential diagnosis of benign and malignant pelvic tumors.

Methods

CEUS was performed on 151 patients with pelvic masses. Subsequently, a qualitative diagnosis was completed using the image enhancement features and tumor parameters. A multiparametric analysis of CEUS images was performed, which included the following parameters: arrival time (AT), time to peak (TTP), peak intensity (PI), and ascent slope (AS). In addition, the qualitative diagnostic efficiency of CEUS was assessed in a multiparametric analysis, and the results were compared with pathological findings.

Results

The patients in the malignant group were older (P=0.001) and had larger lesion PI values (P<0.01) than those in the benign group. The PI difference (PId) and the AS difference (ASd) showed statistical differences (P<0.01) between the myometrium and lesion tissues in the same patient. Moreover, the PId and ASd showed the largest receiver operating characteristic (ROC) curve and area under the ROC curve (AUC), with sensitivities of 90.9% and 91.7% and specificities of 86.4% and 72.5%, respectively.

Conclusions

The quantitative analysis of CEUS provides a new, simpler, and more accurate method for the differential diagnosis of benign and malignant pelvic masses in clinical practice. The sensitivities and specificities of PId and ASd were higher compared to other parameters from the same patient.

Contrast-Enhanced Ultrasound and High Sensitive Doppler for Monitoring Outcomes of Uterine Artery Embolization

RATIONALE AND OBJECTIVES

To monitor fibroid microvascularity using contrast-enhanced ultrasound (CEUS) and a new high-sensitive Doppler mode (SMI) for assessment of uterine artery embolization (UAE) outcomes.

MATERIALS AND METHODS

Forty women with symptomatic uterine fibroids scheduled for UAE were enrolled in this Institutional Review Board-approved study. Subjects underwent three examinations (day 0, 15, and 90 post-UAE) with Color Doppler (CDI), power Doppler (PDI), color and monochrome SMI (cSMI and mSMI), and CEUS imaging of the fibroids. Clips were assessed by two radiologists classifying fibroids based on their vascularity. Fibroid fractional vascularity (FV; % of enhanced pixels within the fibroid) and flow intensity (as mean brightness level of the enhanced pixels) were quantified. Results were analyzed using repeated measures ANOVA and nonparametric Wilcoxon sign rank tests. Inter-reader agreement was assessed with κ-values.

RESULTS

There was overall agreement between readers for all imaging modalities and examination times (P = .25; κ = 0.70). The FV analysis showed statistically significant differences between CEUS and the Doppler imaging modes (CDI, PDI, cSMI, and mSMI) for the three examination times were compared (P < .0001). The comparison using CDI, PDI, and cSMI showed no statistically significant difference (P = .53). The flow intensity analysis comparison between the Doppler imaging modes (CDI, PDI, cSMI and mSMI) and examination times showed statistically significant differences between all the Doppler imaging modalities (P = .02), except for the 90days post-UAE (P = .34). When the comparison was made for CDI, PDI, and cSMI there was no statistically significant differences (P < .47).

CONCLUSION

CEUS and SMI can accurately evaluate fibroid microvascularity, and therefore, can be a noninvasive and accurate method for monitoring outcomes following UAE treatment.

Three-dimensional ultrasound VOCAL combined with contrast-enhanced ultrasound: an alternative to contrast-enhanced magnetic resonance imaging for evaluating ablation of benign uterine lesions

OBJECTIVE

This study explores the feasibility and value of three-dimensional ultrasound virtual organ computer-aided analysis (3D-VOCAL) combined with contrast-enhanced ultrasound (CEUS) for measuring the non-perfused volume (NPV) after microwave ablation (MWA) of benign uterine lesions.

METHODS

Fifty-six patients with uterine myoma (UM) and adenomyosis (AM) treated with MWA were enrolled. NPV measurements were obtained postoperatively using two-dimensional CEUS (2D-CEUS), 3D-VOCAL combined with CEUS and three-dimensional contrast-enhanced magnetic resonance imaging (3D-CEMRI). Bland-Altman analysis and intraclass correlation coefficient (ICC) values were used to analyze the agreement of NPV measurements obtained via 2D-CEUS and the combined method with 3D-CEMRI. The inter- and intra-observer agreements of the NPV values obtained with all three methods were also analyzed.

RESULTS

Considering 3D-CEMRI as the standard, 3D-VOCAL showed greater agreement than 2D-CEUS and higher ICCs (ICC, 0.999 vs. 0.891) than 2D-CEUS for different lesion types and sizes of non-perfusion areas (p < 0.001 for all comparisons). NPV measurements obtained via 2 D-CEUS and 3 D-CEMRI differed significantly for AM and non-perfusion areas with maximum diameter ≥5 cm (p < 0.05) and showed no significant differences (p > 0.05) for UM and non-perfusion areas with maximum diameter <5 cm. The NPV measurements obtained via 3D-VOCAL and 3D-CEMRI did not differ significantly (p > 0.05). The intra- and inter-observer agreements of 3D-VOCAL measurements were better than those of 2D-CEUS and slightly lower than those of 3D-CEMRI.

CONCLUSIONS

3D-VOCAL combined with CEUS provides accurate estimates of NPV after MWA of benign uterine lesions, and offers a reliable, simple and efficient alternative to CEMRI.

Optimized Simultaneous Axial Multifocal Imaging via Frequency Multiplexed Focusing

Simultaneous axial multifocal imaging (SAMI) using a single acoustical transmission was developed to enhance the depth of field. This technique transmits a superposition of axial multifoci waveforms in a single transmission, thus increasing the frame rate. However, since all the waveforms are transmitted at a constant center frequency, there is a tradeoff between attenuation and lateral resolution when choosing a constant frequency for all the axial depths. In this work, we developed an optimized SAMI method by adding frequency dependence to each axial multifocus. By gradually increasing the frequency as a function of the focal depth, this method makes it possible to compensate for the gradually increasing F-number in order to achieve constant lateral resolution across the entire field of view. Alternatively, by gradually decreasing the axial multifoci frequencies as a function of depth, enhanced penetration depth and contrast are obtained. This method, termed frequency multiplexed SAMI (FM-SAMI), is described analytically and validated by resolution and contrast experiments performed on resolution targets, tissue-mimicking phantoms, and ex vivo biological samples. This is the first real-time implementation of a frequency multiplexing approach for axial multifoci imaging that facilitates high-quality imaging at an increased frame rate.

Technological Advancements in Uterus Transplantation

Uterus transplantation is barely a decade old and in a young, evolving field it is hard to identify "technological advances" since it is, in of itself, a technological advance. Nonetheless, one can still identify advances in diagnostic imaging that have improved donor screening to avoid graft losses, highlight the adoption of robotic surgery to make the living donor uterus procurement more minimally invasive, and look to a future of biotechnology like perfusion pumps and bioengineering such as synthetic uterus to increase donor supply. Additional technologies are on the horizon and promise to shape the field further.

Comparison of the diagnostic accuracy of contrast-enhanced/DWI MRI and ultrasonography in the differentiation between benign and malignant myometrial tumors

Background

Various modalities including ultrasonography and magnetic resonance imaging (MRI) have been developed as imaging technique for screening malignant myometrial tumors, but a few studies assessed the diagnostic value of these two techniques in differentiation of benign from malignant myometrial tumors that had been the main purpose of this study.

Materials and methods

This cross-sectional study was performed on 63 women underwent surgery for intrauterine masses that were initially assessed using MRI and ultrasound before surgery at a tertiary hospital in Tehran from 2016 to 2020. Their MRI was reviewed by a reputable radiologist in the field. The findings of histopathological assessment were considered as the gold diagnostic standard.

Results

The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of MRI to detect sarcoma were revealed to be 94.6%, 92.3%, 94.6%, 92.3%, and 93.7% respectively. Ultrasonography had not preferable applicability to differentiate sarcoma from benign tumors with sensitivity, specificity, PPV, NPV and accuracy of 35.1%, 88.4%, 81.2%, 48.9%, and 57.1% respectively. The diagnostic performance of both modalities was not affected by baseline clinical conditions including pain, abnormal uterine bleeding and menopausal status.

Conclusion

MRI but not ultrasonography can effectively differentiate benign from malignant myometrial tumors.

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Pretreatment Diagnosis of malignant myometrial tumors may be challenging.

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MRI with DWI can be considered as a diagnostic tool in leiomyosarcoma.

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Pretreatment distinction between benign and malignant myometrial tumors is necessary.