Tips and tricks for a correct interpretation of contrast-enhanced ultrasound.

Although contrast-enhanced ultrasound (CEUS) is a widespread and easily manageable technique, image interpretation errors can occur due to the operator's inexperience and/or lack of knowledge of the frequent pitfalls, which may cause uncertain diagnosis and misdiagnosis. Indeed, knowledge of the basic physical and technical principles of ultrasound is needed both to understand sonographic image findings and to evaluate the potential and limits of the method. Like the B-mode ultrasound, the quality of the CEUS examination is also subject not only to the adequate manual skill of the operator but also to his/her deep knowledge of the technique which improves the quality of the image helping avoid misleading artifacts. In this review, the main parameters influencing a CEUS examination will be described by taking into account the most common errors and pitfalls and their possible solutions.

Gas-containing renal stones: a red flag for renal infection.

BACKGROUND: Gas in the renal excretory system is described as a consequence of recent procedures but it can be a sign of severe conditions such as fistulas or infections; however, gas-containing renal stones are only rarely encountered. PURPOSE: To describe the association of gas-containing renal stones and urinary tract infection. MATERIAL AND METHODS: We performed a retrospective evaluation of the clinical and imaging findings in a series of six patients with gas-containing renal stones and compared our findings with those of patients with gas-containing renal stones reported in the literature. Urine and stone cultures were used as a diagnostic standard for urinary tract infection. RESULTS: Including the present series, there is a total of 21 patients with gas-containing renal stones in the literature. Based on clinical presentation, urinary tract infection could be suspected in 10 (57%) patients, while urine and/or stone cultures showed infection in 18 of 19 (95%) patients, with only one case with no bacterial growth in both (5%); in the remaining patient the information was not available. CONCLUSION: Gas-containing renal stones are a rarely reported entity usually diagnosed with computed tomography. They are a radiological sign often associated with urinary tract infection that can also be encountered in patients with non-specific renal symptoms.

Radiology in the Era of Value-based Healthcare: A Multi-Society Expert Statement from the ACR, CAR, ESR, IS3R, RANZCR, and RSNA.

Background The Value-Based Healthcare (VBH) concept is designed to improve individual healthcare outcomes without increasing expenditure, and is increasingly being used to determine resourcing of and reimbursement for medical services. Radiology is a major contributor to patient and societal healthcare at many levels. Despite this, some VBH models do not acknowledge radiology's central role; this may have future negative consequences for resource allocation. Methods, findings and interpretation This multi-society paper, representing the views of Radiology Societies in Europe, the USA, Canada, Australia, and New Zealand, describes the place of radiology in VBH models and the health-care value contributions of radiology. Potential steps to objectify and quantify the value contributed by radiology to healthcare are outlined. Published under a CC BY 4.0 license.

Imaging in scrotal trauma: a European Society of Urogenital Radiology Scrotal and Penile Imaging Working Group (ESUR-SPIWG) position statement.

Imaging plays a crucial role in the evaluation of scrotal trauma. Among the imaging modalities, greyscale ultrasound and Colour Doppler ultrasound (CDUS) are the primary techniques with the selective utilisation of advanced techniques such as contrast-enhanced ultrasound (CEUS) and elastography. Despite ultrasound being the mainstay of imaging scrotal trauma, its diagnostic performance is not fully established. Considering these difficulties and their impact on clinical practice, the Scrotal and Penile Imaging Working Group of the European Society of Urogenital Radiology (ESUR-SPIWG) established an expert task force to review the current literature and consolidate their expertise on examination standards and imaging appearances of various entities in scrotal trauma. This paper provides the position statements agreed on by the task force with the aim of providing guidance for the use of imaging especially multiparametric US in scrotal trauma.Key Points• Greyscale and Colour Doppler ultrasound are the mainstay of imaging in patients with scrotal trauma.• Contrast-enhanced ultrasound and elastography are the advanced techniques useful as a problem-solving modality in equivocal cases.• This paper summarises the position statements of the ESUR-SPIWG on the appropriate utilisation of multiparametric ultrasound and other imaging modalities in the evaluation of scrotal trauma.

Nonscrotal Causes of Acute Scrotum.

Acute scrotum is characterized by intense acute scrotal pain, which may be associated with other symptoms and signs such as abdominal pain, inflammation, and fever. Many pathologic conditions can present in this way, most which involve the scrotal contents. Nonscrotal conditions, however, can rarely present clinically only as acute scrotum: among them, renal colic, aneurysm rupture or other causes of retroperitoneal hemorrhage, primary abdominal or pelvic tumors and metastases, pancreatitis, pelvic inflammation, and muscle injuries. The pathophysiologic characteristics of the clinical presentation, clues for diagnosis, and imaging features of a series of nonscrotal lesions presenting clinically with acute scrotal pain are herein reported and illustrated. In patients presenting with acute scrotal symptoms and normal scrotal ultrasound findings, nonscrotal causes of acute scrotal pain should be considered in the differential diagnosis. Therefore, an ultrasound investigation of the abdomen, groin, and thighs is indicated.

Emergency Ultrasound in Trauma Patients: Beware of Pitfalls and Artifacts!

BACKGROUND: Ultrasonography (US) is highly dependent on operators' skills. It is not only a matter of correct scan techniques; there are anatomical structures and variants, as well as artifacts, which can produce images difficult to interpret and which, if not properly understood, can be causes of errors. OBJECTIVES: This paper will review relatively common US pitfalls and artifacts that can be encountered in trauma patients and will offer tips to recognize and avoid them. DISCUSSION: Normal anatomical structures and anatomical variants can mimic fluid collections or perisplenic lesions. Examination along multiple scan planes, real-time observation of movements or repetition of the study after the patient has drunk some fluid or after placing a finger on her/his body wall can help proper identification. The term artifact in US imaging refers to display phenomena not properly representing the imaged structures. This can result in images suggesting fracture lines within organs or at their borders, lung consolidations, or pleural effusions, and abdominal fluid collections. Their knowledge is the first step to recognize them; then, use of multiple scan planes or repetition of the study after voiding or changes of equipment setting can make them disappear or clarify their nature. CONCLUSION: We present possible anatomic pitfalls and artifacts that may affect correct interpretation of US images in patients with abdominal trauma and suggest how to avoid or to clarify them during the examination. Knowing their existence, their appearances, and the reasons why they are produced is important for proper use of this diagnostic technique.

Radiology in the Era of Value-Based Healthcare: A Multi-Society Expert Statement From the ACR, CAR, ESR, IS3R, RANZCR, and RSNA.

BACKGROUND: The Value-Based Healthcare (VBH) concept is designed to improve individual healthcare outcomes without increasing expenditure, and is increasingly being used to determine resourcing of and reimbursement for medical services. Radiology is a major contributor to patient and societal healthcare at many levels. Despite this, some VBH models do not acknowledge radiology's central role; this may have future negative consequences for resource allocation. METHODS, FINDINGS AND INTERPRETATION: This multi-society paper, representing the views of Radiology Societies in Europe, the USA, Canada, Australia, and New Zealand, describes the place of radiology in VBH models and the health-care value contributions of radiology. Potential steps to objectify and quantify the value contributed by radiology to healthcare are outlined.

Ultrasound evaluation of varicoceles: guidelines and recommendations of the European Society of Urogenital Radiology Scrotal and Penile Imaging Working Group (ESUR-SPIWG) for detection, classification, and grading.

Varicoceles are relatively common particularly in asymptomatic men and are even more prevalent in subfertile men, representing the most common potentially correctable cause of male infertility. Ultrasound (US) is the imaging modality of choice for varicocele evaluation, but there is no widely accepted consensus on examination technique, diagnostic criteria, or classification. In view of this uncertainty, the guideline writing group (WG) of the European Society of Urogenital Radiology (ESUR) Scrotal and Penile Imaging Working Group (ESUR-SPIWG) undertook a literature review and assessment of the quality of relevant evidence. The group then produced evidence-based recommendations for varicocele US examination, interpretation, and classification by consensus agreement. The results are presented in the form of 15 clinical questions with a brief summary of the relevant evidence and the authorised recommendations from the SPIWG. This paper provides a short summary of the evidence evaluation and the complete recommendations.Key Points• Varicocele is a common clinical problem; it is highly prevalent amongst subfertile men and the most common potentially correctable cause of male infertility. • Ultrasound is the imaging modality of choice for varicocele assessment, but there is no generally agreed consensus on the US examination technique or the criteria that should be used for diagnosis, grading, and classification. • This paper summarises the recommendations of the ESUR-SPIWG for standardising the US assessment of varicoceles. This includes examination technique, image interpretation, classification, and reporting.

Evaluation of Intratesticular Lesions With Strain Elastography Using Strain Ratio and Color Map Visual Grading: Differentiation of Neoplastic and Nonneoplastic Lesions.

OBJECTIVE: To investigate the role of strain elastography using calculated strain ratio and visual elastography score in differentiating nonneoplastic, benign, and malignant neoplastic intratesticular lesions. MATERIALS AND METHODS: The study was approved by the hospital review board as a retrospective review of 86 patients examined with gray scale, color Doppler ultrasonography and strain elastography (visual elastography score and strain ratio). Sensitivity, specificity, and positive and negative likelihood ratio of color Doppler and stain elastography were documented. Receiver operator characteristic curves assessed the diagnostic accuracy of strain elastography to discriminate nonneoplastic, benign, and malignant neoplasms. Histology or follow-up ultrasonography determined lesion character. RESULTS: Thirty-one of 86 (36.0%) intratesticular malignant neoplasms, 17 of 86 (19.8%) benign neoplasms, and 38 of 86 (44.2%) nonneoplastic lesions were confirmed with histology (n = 52) or follow-up sonography (n = 34); 89.5% of intratesticular lesions were heterogeneous or hypoechoic on gray scale, with no difference between benign and malignant. Sensitivity, specificity, positive and negative likelihood ratio for nonneoplasm versus neoplasm were documented: color Doppler: 68.8%, 97.4%, 26.5, 0.32; visual elastography score: 81.3%, 57.9%, 1.93, 0.32; strain ratio: 68.8%, 81.6%, 3.73, 0.38. Neoplastic lesions showed a higher strain ratio than nonneoplastic lesions (P < .001), with strong correlation between median strain ratio and visual elastography score (Spearman's coefficient, 0.693; P < .001). Strain ratio is a significantly better assessment than visual elastography score for malignant lesions (P = .025). Logistic regression analysis revealed significant associations between size (P = .001), hypervascularity (P < .001), and malignancy. CONCLUSION: Higher strain ratio and visual elastography score are associated with neoplastic lesions and offer an alternative to assess tissue characteristics but do not improve the diagnostic accuracy when compared with the color Doppler pattern.

There are more anatomical variants in heaven and earth, Horatio, than are dreamt of in our philosophy: the precaval left renal artery.

AIM: To describe the CT findings in eight patients with left-sided inferior vena cava (IVC) in whom the left renal artery presented a precaval course (pLRA). MATERIALS AND METHODS: We searched the teaching files of six radiology departments for patients with pLRAs. Eight patients were found, and the available imaging studies and clinical histories were reviewed. Associated vascular and renal anomalies were noted. RESULTS: No patient had been examined for problems related to the vascular anomaly found. Four had a double IVC and two a solitary left IVC; in all, the left-sided IVCs had hemiazygos continuation. One patient had situs viscerum inversus. In one case, there was a left kidney in left iliac fossa. CONCLUSION: Although rare and probably overlooked, a pLRAs can be encountered in patients with situs viscerum inversus or presenting a left-sided IVC with hemiazygos continuation. These vessels can cause technical problems during surgery at the left renal hilum and should be specifically searched for in patients with vascular anomalies.

MRI of the scrotum: Recommendations of the ESUR Scrotal and Penile Imaging Working Group.

OBJECTIVES: The Scrotal and Penile Imaging Working Group (SPI-WG) appointed by the board of the European Society of Urogenital Radiology (ESUR) has produced recommendations for magnetic resonance imaging (MRI) of the scrotum. METHODS: The SPI-WG searched for original and review articles published before September 2016 using the Pubmed and Medline databases. Keywords used were 'magnetic resonance imaging', 'testis or testicle or testicular', 'scrotum', 'intratesticular', 'paratesticular', 'extratesticular' 'diffusion-weighted', 'dynamic MRI'. Consensus was obtained among the members of the subcommittee. The expert panel proposed recommendations using Oxford Centre for Evidence-Based Medicine 2011 Levels of Evidence. RESULTS: The recommended MRI protocol should include T1-, T2-weighted imaging, diffusion-weighted imaging and dynamic contrast-enhanced MRI. Scrotal MRI can be clinically applied for lesion characterisation (primary), including both intratesticular and paratesticular masses, differentiation between germ-cell and non-germ-cell neoplasms (evolving), characterisation of the histological type of testicular germ cell neoplasms (TGCNs, in selected cases), local staging of TGCNs (primary), acute scrotum (in selected cases), trauma (in selected cases) and undescended testes (primary). CONCLUSIONS: The ESUR SPI-WG produced this consensus paper in which the existing literature on MRI of the scrotum is reviewed. The recommendations for the optimal imaging technique and clinical indications are presented. KEY POINTS: • This report presents recommendations for magnetic resonance imaging (MRI) of the scrotum. • Imaging acquisition protocols and clinical indications are provided. • MRI is becoming established as a worthwhile second-line diagnostic tool for scrotal pathology.

Imaging Features of Paratesticular Masses.

In this pictorial essay, we review the sonographic and other imaging findings of paratesticular masses in correlation with the pathologic findings. The examples include benign and malignant tumors and also non-neoplastic mass lesions of the paratesticular structures. Diagnostic sonographic findings of these mass lesions as well as correlative findings of other imaging methods are presented.

Sonography of Scrotal Wall Lesions and Correlation With Other Modalities.

The scrotal wall may be involved in a variety of pathologic processes. Such lesions may rise primarily from the layers of the scrotum or may be due to a process arising from scrotal content. Imaging is not needed in most cases, but it may be useful for making such differentiations and for evaluation of possible involvement of the testes and epididymides in cases of primary wall abnormalities. This pictorial essay will show the imaging findings observed in a variety of pathologic conditions affecting the scrotal wall, both common and unusual ones, with an emphasis on clinically relevant findings and features that lead to a specific diagnosis.

Imaging of mesothelioma of tunica vaginalis testis.

OBJECTIVES: To describe the imaging findings in a series of patients with mesothelioma of the tunica vaginalis testis. METHODS: We reviewed clinical data, imaging findings and follow-up information in a series of 10 pathology-proven cases of mesothelioma (all had US; 2 had MR) of the tunica vaginalis. RESULTS: A variety of patterns could be observed, the most common (5/10) being a hydrocele with parietal, solid and hypervascular vegetations; one patient had a septated hydrocele with hypervascular walls; one had multiple, solid nodules surrounded by a small, physiological quantity of fluid; one a cystic lesion with thick walls and vegetations compressing the testis; two had a solid paratesticular mass. MR showed multiple small nodules on the surface of the tunica vaginalis in one case and diffuse thickening and vegetations in the other one; lesions had low signal intensity on T2-w images and were hypervascular after contrast injection. CONCLUSIONS: A preoperative diagnosis of mesotheliomas presenting as solid paratesticular masses seems very difficult with imaging. On the contrary, the diagnosis must be considered in patients in whom a hydrocele with parietal vegetations is detected, especially if these show high vascularity. KEY POINTS: Mesotheliomas of the tunica vaginalis are rare, often challenging to diagnose preoperatively. Most common finding is a complex hydrocele with hypervascular parietal vegetations. Septated hydrocele, nodules without hydrocele, a thick-walled paratesticular cyst are less common. Preoperative diagnosis may allow aggressive surgical approach and, possibly, a better prognosis.

Incidentally detected non-palpable testicular tumours in adults at scrotal ultrasound: impact of radiological findings on management Radiologic review and recommendations of the ESUR scrotal imaging subcommittee.

OBJECTIVES: The increasing detection of small testicular lesions by ultrasound (US) in adults can lead to unnecessary orchiectomies. This article describes their nature, reviews the available literature on this subject and illustrates some classical lesions. We also suggest recommendations to help characterization and management. METHODS: The ESUR scrotal imaging subcommittee searched for original and review articles published before May 2015 using the Pubmed and Medline databases. Key words used were 'testicular ultrasound', 'contrast-enhanced sonography', 'sonoelastography', 'magnetic resonance imaging', 'testis-sparing surgery', 'testis imaging', 'Leydig cell tumour', 'testicular cyst'. Consensus was obtained amongst the members of the subcommittee, urologist and medical oncologist. RESULTS: Simple cysts are frequent and benign, and do not require follow up or surgery. Incidentally discovered small solid testicular lesions detected are benign in up to 80 %, with Leydig cell tumours being the most frequent. However, the presence of microliths, macrocalcifications and hypoechoic areas surrounding the nodule are findings suggestive of malignant disease. CONCLUSION: Asymptomatic small testicular lesions found on ultrasound are mainly benign, but findings such as microliths or hypoechoic regions surrounding the nodules may indicate malignancy. Colour Doppler US remains the basic examination for characterization. The role of newer imaging modalities in characterization is evolving. KEY POINTS: • Characterization of testicular lesions is primarily based on US examination. • The role of MRI, sonoelastography, contrast-enhanced ultrasound is evolving. • Most small non-palpable testicular lesions seen on ultrasound are benign simple cysts. • Leydig cell tumours are the most frequent benign lesions. • Associated findings like microliths or hypoechoic regions may indicate malignancy.

Imaging of Bilateral Synchronous Testicular Tumors of Different Histologic Types and Implications for Surgical Management.

The clinical history and imaging and pathologic findings in 4 patients with bilateral synchronous testicular tumors of dissimilar histologic types were reviewed. All patients had a large scrotal mass on one side and a smaller nodule on the other one. The appearances of each pair of lesions were different enough to suggest that they could possibly be of different histologic types. The most important role of imaging, however, was its capability to guide the surgical approach to these patients: in 1 case, the smallest lesion was recognized as an epidermoid cyst; in 2 others a conservative approach was deemed possible, given the lesions' small volumes and peripheral locations.

Sonographic appearances of the postoperative testis.

PURPOSE: To describe the sonographic findings observed in the testis in patients who have undergone testicle-sparing surgery and surgical biopsies. METHODS: We reviewed the color Doppler sonographic findings from 14 patients after testicular interventions: 2 open biopsy procedures for infertility and 12 testicle-sparing surgical procedures (1 for spontaneous intratesticular hemorrhage and 11 for small tumors). Ten patients had benign tumors; one had a malignancy. Three patients were symptomatic; all others were studied as follow-up. RESULTS: Hypoechoic and hypovascular lesions at site of surgery were seen in 10 of the 11 patients after tumorectomy; no changes were observed in one patient. The lesions were either linear or an irregularly triangular shape, located at the surgical site, and interpreted as scars. Retraction of the testicular surface was detected in two cases. In the eight patients who underwent follow-up, lesions disappeared in one case, became smaller in two, and remained stable in five. Of the two patients who underwent biopsy, one developed peritesticular hematoma, and both had late hypoechoic scars in the testis. CONCLUSIONS: Hypoechoic and hypovascular scars are a "normal" postoperative pattern after testicle-sparing surgery. They are either linear or triangular, with rectilinear margins. Such findings need to be correctly interpreted and not misinterpreted as recurrences.

Follow-up of recurrences of limb soft tissue sarcomas in patients with localized disease: performance of ultrasound.

OBJECTIVES: To evaluate diagnostic performance of ultrasound in the detection of local recurrences in patients with localized soft tissue sarcomas of the limb. METHODS: An analysis of patients treated for soft tissue sarcomas between 2005 and April 2014 was performed. Sixty-eight patients (men/women, 36:32; age range, 18-84 years) were evaluated. Sensitivity, specificity with 95% confidence intervals (CIs), positive predictive value (PPV), pre-test probability (the prevalence), negative predictive value (NPV), likelihood ratio for positive results (LH+), accuracy and post-test probability (post-P) of ultrasound were reported on a per patient basis using surgical findings and clinical follow-up as reference standard. Effects of independent variables (US equipment, age and sex, body mass index, radiologist) were considered. Comparison with MR was also performed. RESULTS: The overall sensitivity and specificity were 0.88 (0.60-0.94) and 0.94 (0.86-0.98). PPV, pre-test probability, NPV, LH+, accuracy and post-P: 0.83/0.25/0.96/14.9/0.92/0.83. There were two false negative cases both graded as G3 and deeply located and three false positive US cases. Diagnostic accuracy was not dependent by US machine (p = 0.08), age and sex (p = 0.16), body mass index (p = 0.07) and radiologists (p = 0.07). CONCLUSIONS: Diagnostic accuracy of ultrasound was relatively high. Negative US results excluded the presence of a local recurrence with acceptable accuracy. KEY POINTS: • US accuracy is relatively high in sarcoma follow-up. • Negative US results exclude the presence of local recurrence with acceptable accuracy. • US may miss a small proportion of lesions. • False positive US cases are rare.

Testicular microlithiasis imaging and follow-up: guidelines of the ESUR scrotal imaging subcommittee.

OBJECTIVES: The subcommittee on scrotal imaging, appointed by the board of the European Society of Urogenital Radiology (ESUR), have produced guidelines on imaging and follow-up in testicular microlithiasis (TML). METHODS: The authors and a superintendent university librarian independently performed a computer-assisted literature search of medical databases: MEDLINE and EMBASE. A further parallel literature search was made for the genetic conditions Klinefelter's syndrome and McCune-Albright syndrome. RESULTS: Proposed guidelines are: follow-up is not advised in patients with isolated TML in the absence of risk factors (see Key Points below); annual ultrasound (US) is advised for patients with risk factors, up to the age of 55; if TML is found with a testicular mass, urgent referral to a specialist centre is advised. CONCLUSION: Consensus opinion of the scrotal subcommittee of the ESUR is that the presence of TML alone in the absence of other risk factors is not an indication for regular scrotal US, further US screening or biopsy. US is recommended in the follow-up of patients at risk, where risk factors other than microlithiasis are present. Risk factors are discussed and the literature and recommended guidelines are presented in this article. KEY POINTS: • Follow up advised only in patients with TML and additional risk factors. • Annual US advised for patients with risk factors up to age 55. • If TML is found with testicular mass, urgent specialist referral advised. • Risk factors - personal/ family history of GCT, maldescent, orchidopexy, testicular atrophy.

Grayscale and color Doppler features of testicular lymphoma.

Pooled data from 16 radiology centers were retrospectively analyzed to seek patients with pathologically proven testicular lymphoma and grayscale and color Doppler images available for review. Forty-three cases were found: 36 (84%) primary and 7 (16%) secondary testicular lymphoma. With unilateral primary lymphoma, involvement was unifocal (n = 10), multifocal (n = 11), or diffuse (n = 11). Synchronous bilateral involvement occurred in 6 patients. Color Doppler sonography showed normal testicular vessels within the tumor in 31 of 43 lymphomas (72%). Testicular lymphoma infiltrates through the tubules, preserving the normal vascular architecture of the testis. Depiction of normal testicular vessels crossing the lesion is a useful adjunctive diagnostic criterion.