Use of contrast enhanced ultrasound in testicular diseases: A comprehensive review

Testicular ultrasonic microvascular density in assessing spermatogenesis and predicting successful sperm retrieval

Background

The relationship between microcirculatory disorders and testicular spermatogenesis is an area of ongoing interest among urologists. The objective of this prospective observational study was to investigate the correlation between testicular microcirculation and spermatogenesis, as well as the predictive value of ultrasonic microvascular density (UMVD) and ultrasonographic volume estimation (UVE) in successful sperm retrieval among men with non-obstructive azoospermia (NOA).

Methods

Testicular UMVD derived from Angio PLUSTM Planwave Ultrasensitive Imaging (AP), UVE were obtained. Participants were divided into 4 groups (normozoospermia; asthenozoospermia, teratozoospermia, or asthenoteratozoospermia; oligozoospermia; NOA).

Results

The study included a total of 875 participants. No significant difference was found in UMVD-mean between different semen groups (P>0.05). A total of 108 participants with NOA underwent microdissection testicular sperm extraction (micro-TESE). Participants with successful sperm retrieval (40 cases) showed significant differences in testicular UMVD and UVE compared to those with negative retrieval (68 cases) (P<0.01). We generated receiver operating characteristic (ROC) curves for UMVD and testicular UVE to differentiate participants with successful sperm retrieval from those without. The area under the curve (AUC) was 0.760 [95% confidence interval (CI): 0.658-0.849, P<0.01] for UMVD and 0.716 (95% CI: 0.609-0.822, P<0.01) for testicular UVE, respectively. The optimal cutoff value was determined based on the maximum Youden index. When UMVD was set at 28.50/cm2, its sensitivity and specificity were calculated as 57.5% and 85.3%, respectively. For testicular UVE, a cutoff value of 8.94 mL resulted in a sensitivity of 60.0% and specificity of 82.4%. Combining UMVD with testicular UVE improved diagnostic performance (AUC: 0.856, 95% CI: 0.772-0.929, P<0.01) with a sensitivity of 79.4% and specificity of 77.5%.

Conclusions

The present study demonstrates the utility of AP as a predictive tool for successful sperm retrieval prior to micro-TESE. Furthermore, the combination of testicular UMVD and UVE provides a highly valuable diagnostic approach for predicting micro-TESE success and can be routinely implemented before the procedure. A testicular UMVD exceeding 28.50/cm2 and a testicular UVE larger than 8.94 mL strongly indicate favorable outcomes in terms of sperm retrieval.

Comparison of Testicular Sonography and Elastography Findings With Semen Parameters in Cases Investigated for Infertility

OBJECTIVES

This study aimed to investigate the correlation between testicular shear wave elastography (SWE) values and semen analysis results in men with infertility.

METHODS

This was a retrospective case-control study. Patients were categorized as normal, abnormal, or azoospermic based on sperm analysis results. Testicular volume was measured using B-mode ultrasonography using the Lambert formula. Subsequently, 40-80 regions of interest measuring 1.5 × 1.5 mm were manually positioned in both testicles based on their size, and two-dimensional SWE was applied through virtual touch imaging quantification software.

RESULTS

The patients had a mean age of 33.79 ± 6.3 years, with semen analysis revealing normal results in 15 patients (22.4%), pathological findings in 35 patients (52.2%), and azoospermia in 17 patients (25.4%). Right, left, total, and mean testicular volumes were significantly lower in patients with azoospermia compared to those in both normal and impaired semen parameters (P < .05). Conversely, testicular elastography scores were higher in patients with azoospermia than in the other groups (P < .05). The significant negative correlation between volume and elastographic findings remained independent of age (r = 0.4, P < .001). The accuracy rates for detecting impaired semen parameters and azoospermia were 94.3% and 94.1%, respectively, after considering factors such as age, testicular volume (right/left/total), and elastography (right/left/total). Notably, the total mean elastography score ranked first, with 100% in the independent normalized importance distribution of these variables.

CONCLUSION

SWE can be used effectively alone or in combination with other diagnostic tools to evaluate histopathological changes in the testicles of male patients with infertility.

Diagnostic Performance of Contrast-Enhanced Ultrasound in Testicular Space-Occupying Lesions: A Systematic Review and Meta-analysis

PURPOSE

Contrast-enhanced ultrasound (CEUS) has been increasingly used for the diagnostic identification of neoplasms due to its ability to visualize the microvascularization of lesions. In the study of testicular abnormalities, the appropriate use of CEUS can improve the diagnostic accuracy of conventional gray-scale ultrasound and color Doppler ultrasound (CDUS). The purpose of this study is to comprehensively evaluate the diagnostic performance of CEUS in testicular space-occupying lesions.

METHODS

A comprehensive search of PubMed, Embase, Cochrane Library, and Web of Science databases was conducted from the inception of each database to November 16, 2022 for relevant studies. The required data were extracted, and the methodological quality of the studies was assessed using the QUADAS-2 tool. The diagnostic value of CEUS was assessed by calculating the combined sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio, and a summary receiver operating characteristic (SROC) curve was used to conduct this meta-analysis.

RESULTS

A total of six studies with 354 testicular space-occupying lesions were included in the analysis. The results showed that CEUS could provide additional useful information for the diagnosis of testicular space-occupying lesions, with a sensitivity of 0.92 (95% CI:0.82, 0.97), specificity of 0.91 (95% CI:0.80, 0.96), diagnostic odds ratio of 114 (95% CI:25, 528), respectively, and an overall diagnostic accuracy expressed as area under the SROC curve (AUC) of 0.97 (95% CI:0.95-0.98). Significant heterogeneity was seen in the sensitivity with I2 = 82.53% (95% CI:69.44-95.61). Subgroup analysis revealed that the proportion of infertile patients selected may be the source of heterogeneity.

CONCLUSION

CEUS can be used to diagnose testicular space-occupying lesions more accurately and improve diagnostic accuracy when the conventional US cannot accurately differentiate the type of lesion. In particular, CEUS should be recommended for the identification of microscopic lesions so that physicians can provide patients with more appropriate interventions to avoid unnecessary orchiectomy.

Contrast-enhanced ultrasound (CEUS) for the characterization of intra-scrotal lesions

Contrast-enhanced ultrasound (CEUS) has emerged as a promising imaging modality for the characterization of hepatic and renal lesions. However, there is a paucity of data describing the use of CEUS for the evaluation of intra-scrotal pathology. In the following review, we describe the clinical utility of CEUS for the characterization and differentiation of common and uncommon intra-scrotal conditions, including testicular torsion, infection, trauma, and benign and malignant intratesticular and extratesticular neoplasms. In addition, we outline key principles of CEUS and provide case examples from our institution.

Apparent diffusion coefficient histogram in the differentiation of benign and malignant testicular tumors

Purpose: This retrospective study assessed the value of histogram parameters of the apparent diffusion coefficient (ADC) map (HA) in differentiating between benign and malignant testicular tumors. We compared the diagnostic performance of two different volume-of-interest (VOI) placement methods: VOI 1, the entire tumor; VOI 2, the tumor excluding its cystic, calcified, hemorrhagic, and necrotic portions. Materials and methods: We retrospectively evaluated 45 patients with testicular tumors examined with scrotal contrast-enhanced magnetic resonance imaging. These patients underwent surgery with the pathological result of seven benign and 39 malignant tumors. We calculated the HA parameters, including mean, median, maximum, minimum, kurtosis, skewness, entropy, standard deviation (SD), mean of positive pixels, and uniformity of positive pixels by the two different VOI segmentation methods. We compared these parameters using the chi-square test, Mann-Whitney U test, and area under the receiver operating characteristic curve (AUC) to determine their optimal cut-off, sensitivity (Se), and specificity (Sp). Result: This study included 45 patients with 46 testicular lesions (seven benign and 39 malignant tumors), one of which had bilateral testicular seminoma. With the VOI 1 method, benign lesions had significantly lower maximum ADC (p = 0.002), ADC skewness (p = 0.017), and ADC variance (p = 0.000) than malignant lesions. In contrast, their minimum ADC was significantly higher ADC (p = 0.000). With the VOI 2 method, the benign lesions had significantly higher ADC SD (p = 0.048) and maximum ADC (p = 0.015) than malignant lesions. In contrast, their minimum ADC was significantly lower (p = 0.000). With the VOI 1 method, maximum ADC, ADC variance, and ADC skewness performed well in differentiating benign and malignant testicular lesions with cut-offs (Se, Sp, AUC) of 1846.000 (74.4%, 100%, 0.883), 39198.387 (79.5%, 85.7%, 0.868), and 0.893 (48.7%, 100%, 0.758). Conclusion: The HA parameters showed value in differentiating benign and malignant testicular neoplasms. The entire tumor VOI placement method was preferable to the VOI placement method excluding cystic, calcified, hemorrhagic, and necrotic portions in measuring HA parameters. Using this VOI segmentation, maximum ADC performed best in discriminating benign and malignant testicular lesions, followed by ADC variance and skewness.

Multiparametric Ultrasound for Diagnosing Testicular Lesions: Everything You Need to Know in Daily Clinical Practice

BACKGROUND

Ultrasonography (US) represents the gold standard imaging method for the assessment of testicular lesions (TL). The gray-scale (GSUS) and color-Doppler (CDUS) ultrasound examination allow sonographers to investigate the size, margins, echotexture, and vascular features of TLs with the aim to differentiate benign from malignant lesions. Recently, the use of contrast-enhanced US (CEUS) and sonoelastography (SE) has led to further improvements in the differential diagnosis of TL. Although GSUS and CDUS are often sufficient to suggest the benign or malignant nature of the TL, CEUS can be decisive in the differential diagnosis of unclear findings, while SE can help to strengthen the diagnosis. The contemporary combination of GSUS, CDUS, CEUS, and SE has led to a new diagnostic paradigm named multiparametric US (mp-US), which is able to provide a more detailed characterization of TLs than single techniques alone. This narrative and pictorial review aimed to describe the mp-US appearance of several TLs.

METHODS

An extensive Medline search was performed to identify studies in the English language focusing on the mp-US evaluation of TLs.

RESULTS

A practical mp-US "identity card" and iconographic characterization of several benign and malignant TLs is provided herein.

CONCLUSIONS

The mp-US characterization of TL reported herein can be useful in daily clinical practice.

Role and added value of contrast enhanced ultrasound of the painful scrotum in the emergency setting

Emergency imaging of the scrotum is part of routine medical practice. Indications include epididymitis/epididymo-orchitis, testicular torsion, trauma, tumors and infarction. Prompt diagnosis and management are needed to ensure optimal patient outcome. Ultrasound (US) is the initial, and often the only, imaging modality for testicular pathologies. Usually, B-mode and color Doppler US are adequate. In challenging cases, contrast-enhanced US (CEUS) facilitates final diagnosis or increases the examiner's confidence by confirming findings on non-enhanced US. This paper elaborates on the examination technique of CEUS for testicular pathologies, thereby showing its added value over baseline US techniques in the emergency setting.

Testicular cavernous hemangioma masquerading as testicular malignancy

Cavernous hemangiomas are benign tumors of vascular origin that can develop in any part of the body. However, its occurrence in the testis is rare. To the best of our knowledge, we are reporting the first case of a patient with cavernous hemangioma with concern for an extracapsular extension on ultrasound imaging.

Contrast-Enhanced Ultrasonography (CEUS) in Imaging of the Reproductive System in Dogs: A Literature Review

The use of contrast-enhanced ultrasound (CEUS) has been widely reported for reproductive imaging in humans and animals. This review aims to analyze the utility of CEUS in characterizing canine reproductive physiology and pathologies. In September 2022, a search for articles about CEUS in canine testicles, prostate, uterus, placenta, and mammary glands was conducted on PubMed and Scopus from 1990 to 2022, showing 36 total results. CEUS differentiated testicular abnormalities and neoplastic lesions, but it could not characterize tumors. In prostatic diseases, CEUS in dogs was widely studied in animal models for prostatic cancer treatment. In veterinary medicine, this diagnostic tool could distinguish prostatic adenocarcinomas. In ovaries, CEUS differentiated the follicular phases. In CEH-pyometra syndrome, it showed a different enhancement between endometrium and cysts, and highlighted angiogenesis. CEUS was shown to be safe in pregnant dogs and was able to assess normal and abnormal fetal-maternal blood flow and placental dysfunction. In normal mammary glands, CEUS showed vascularization only in diestrus, with differences between mammary glands. CEUS was not specific for neoplastic versus non-neoplastic masses and for benign tumors, except for complex carcinomas and neoplastic vascularization. Works on CEUS showed its usefulness in a wide spectrum of pathologies of this non-invasive, reliable diagnostic procedure.

The evolving role of contrast-enhanced ultrasound in urology: a review

PURPOSE

Ultrasound's versatility and ease of use has expanded its application in many clinical settings. Technological advancements with contrast-enhanced ultrasound (CEUS) have allowed high quality imaging similar to CT or MRI with lower risk of contrast toxicity and radiation exposure. In this review article we examine the development of CEUS and its vast applications in the field of urology.

METHODS

A PubMed literature search was performed using keywords: contrast enhanced ultrasound, prostate cancer, renal cancer, and multiparametric ultrasound.

RESULTS

The development of CEUS has improved transrectal ultrasound imaging with increased detection of prostate cancer (PCa). Further enhancements of CEUS such as subharmonic imaging (SHI), flash replenishment imaging (FRI) and contrast ultrasound dispersion imaging (CUDI) allow improved PCa diagnosis. CEUS has also emerged as an important tool in characterizing suspicious renal mass without compromising renal function with contrast imaging.

CONCLUSION

CEUS has modernized imaging and diagnosis of prostate and renal cancer. Future advancements and utilization of CEUS will allow its expansion into other urological subspecialties.

An Overview of the Role of Multiparametric MRI in the Investigation of Testicular Tumors

Simple Summary

Although conventional ultrasonography remains the primary imaging modality for the assessment of testicular tumors, multiparametric MRI of the scrotum, which combines morphologic and functional data, serves as a powerful adjunct. Based on the recommendations issued by the Scrotal and Penile Imaging Working Group of the European Society of Urogenital Radiology, scrotal MRI is strongly recommended after equivocal US findings. In cases of testicular masses, the main clinical indications are as follows: lesion characterization when sonographic findings are non-diagnostic, discrimination between germ-cell and non-germ-cell testicular tumors, local staging of testicular tumors in patients who are candidates for testis-sparing surgery, and preoperative histological characterization of testicular germ-cell tumors in selected cases. This article aims to provide an overview of the role of multiparametric MRI in the investigation of testicular tumors.

Abstract

Conventional ultrasonography represents the mainstay of testis imaging. In cases in which ultrasonography is inconclusive, scrotal MRI using a multiparametric protocol may be used as a useful problem-solving tool. MRI of the scrotum is primarily recommended for differentiating between benign and malignant testicular masses when sonographic findings are ambiguous. This technique is also accurate in the preoperative local staging of testicular tumors and, therefore, is recommended in patients scheduled for testis-sparing surgery. In addition, MRI may provide valuable information regarding the histological characterization of testicular germ-cell tumors, in selected cases. Scrotal MRI may also help in the differentiation between testicular germ-cell neoplasms and non-germ-cell neoplasms. Axial T1-weighted imaging, axial and coronal T2-weighted imaging, axial diffusion-weighted imaging, and coronal subtracted dynamic contrast-enhanced imaging are the minimum requirements for scrotal MRI. A variety of MRI techniques—including diffusion tensor imaging, magnetization transfer imaging, proton MR spectroscopy, volumetric apparent diffusion coefficient histogram analysis, and MRI-based radiomics—are being investigated for testicular mass characterization, providing valuable supplementary diagnostic information. In the present review, we aim to discuss clinical indications for scrotal MRI in cases of testicular tumors, along with MRI findings of common testicular malignancies.

Contrast-enhanced and microvascular ultrasound imaging features of testicular lymphoma: report of five cases and review literature

Background

To retrospectively investigate the grey-scale, Doppler, contrast-enhanced and microvascular ultrasound of five patients with primary testicular lymphoma of our institute through review literature analysis.

Methods

From January to November 2020, five patients with primary testicular lymphoma confirmed by histology were preoperatively investigated with a standardized sonographic protocol including contrast-enhanced and microvascular ultrasound.

Results

Conventional ultrasound showed localized hypoechogenicity represented with solitary (2 of 5), multiple lesions (2 of 5), or entire testicular involvement (1 of 5). Increased blood flow appeared in color Doppler ultrasound with straight vascular sign (4 of 5). In contrast-enhanced ultrasound images confirmed this pattern (4 of 5) and presented hyper enhancement with enlarged range. On microvascular ultrasound imagings, all lesions were presented with straight and parallel course of intralesional vessels (5 of 5).

Conclusions

Here, we identified an increased vascularity with enlarged range on contrast-enhanced ultrasound along with a linear nonbranching pattern by vascular sign on microvascular ultrasonographic of testicular lymphoma.

The Value of Contrast-Enhanced Ultrasound (CEUS) in Differentiating Testicular Masses: A Systematic Review and Meta-Analysis

Ultrasound (US) still represents the mainstay of scrotal imaging. However, contrast-enhanced ultrasound (CEUS) is a relatively novel, but increasingly utilized diagnostic modality. In consequence, we performed a systematic review (SR) and pooled meta-analysis to investigate the diagnostic performance of CEUS in the evaluation of testicular masses (TM). A SR up to June 2021 was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. The diagnostic performance of CEUS was evaluated basing on two different endpoints: neoplastic vs. non-neoplastic and malignant vs. benign TM. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) from eligible studies were pooled and summary receiver operating characteristic (SROC) curves were constructed for each endpoint. Overall, six qualified studies were deemed suitable for this meta-analysis. Diagnostic performance of CEUS showed an accuracy of 0.96 in detecting neoplastic masses (sensitivity of 0.89, PPV of 0.85, specificity of 0.62, and NPV of 0.69) and an accuracy of 0.96 in detecting malignant masses (sensitivity of 0.86, PPV of 0.73, specificity of 0.87, and NPV of 0.91). Taken together, CEUS may represent a promising minimally invasive diagnostic tool for characterization of TM, since it allows clinicians to identify neoplastic lesions and exclude malignant tumor.