Contrast-enhanced ultrasonography in blunt abdominal trauma: considerations after 5 years of experience

Spread and feasibility of non-operative management (NOM) of traumatic splenic injuries in adults: a national survey

In hemodynamically stable adults sustaining a splenic trauma, non-operative management (NOM) represents the standard approach even in high-severity injuries. However, knowledge, structural, and logistic limitations still reduce its wider diffusion. This study aims to identify such issues to promote the safe and effective management of these injuries.A survey was developed using the SurveyMonkey® software and spread nationally in Italy. The survey was structured into: (1) Knowledge of classification systems; (2) Availability to refer patients; (3) Patients monitoring and follow-up; (4) Center-related.The survey was filled in by 327 surgeons, with a completeness rate of 63%. Three responders out of four are used to manage trauma patients. Despite most responders knowing the existing classifications, their use is still limited in daily practice. If a patient needs to be centralized, the concern about possible clinical deterioration represent the main obstacle to achieving a NOM. The lack of protocols does not allow standardization of patient surveillance according to the degree of injury. The imaging follow-up is not standardized as well, varying between computed tomography, ultrasound, and contrast-enhanced ultrasound.The classification systems need to be spread to all the trauma-dedicated physicians, to speak a common language. A more rational centralization of patients should be promoted, ideally through agreements between peripheral and reference centers, both at regional and local level. Standardized protocols need to be shared nationally, as well as the clinical and imaging follow-up criteria should be adapted to the local features.

Contrast-enhanced ultrasound (CEUS) in the follow-up of abdominal solid organ trauma: an international survey prior to the PseAn study

BACKGROUND

The blunt and penetrating abdominal trauma follow-up relies on contrast CT scan to detect solid organ injuries. CEUS is not widely used worldwide, despite its accuracy and feasibility in identifying parenchymal and vascular lesions. This survey aims to define the current use of CEUS in Trauma Centers and the expectations of Emergency Surgeons regarding its role.

METHODS

We sent an online questionnaire composed of 10 questions to trauma physicians worldwide during the period of September 2022 to March 2023.

RESULTS

59 participants from 53 different centers answered the questionnaire. 76.2% of the enrolled participants have CEUS available at their Institution, and 49.2% think that it can replace CT scan. Contrast-CT scan remains the preferred option in the follow-up of blunt liver (69.5%), spleen (72.9%) and kidney (76.3%) injuries, followed by CEUS which is used in 18.6% for liver, 20.3% for spleen and 15.3% for kidney injuries. The results are similar for penetrating abdominal trauma, with contrast CT scan being the first-line imaging technique (91.5% for liver, 91.5% for spleen and 88.1% for kidney injuries), followed by CEUS (5.1% for liver, 5.1% for spleen and 6.8% for kidney injuries).

CONCLUSIONS

Our survey shows that CEUS is still underutilized in the follow-up of abdominal trauma, even though many emergency surgeons consider it as a valid alternative to contrast CT scan.

Detection of post-traumatic abdominal pseudoaneurysms by CEUS and CT: A prospective comparative global study (the PseAn study)-study protocol

The success of non-operative management in trauma increased with the availability of new-generation CT scan machines, endoscopy, and angiography, becoming the standard of care in hemodynamically stable trauma patients with abdominal solid organ injuries, with a success rate of 78% to 98%. Post-traumatic pseudoaneurysms (PAs) can develop at any region of an injured artery and they may cause delayed bleeding in splenic or hepatic trauma, with an incidence in patients treated with NOM of 2%-27% and 1.2%-6.1% respectively. Diagnosis is made by angiography, contrast-enhanced computer tomography (CT), or Doppler Ultrasound (US) while the use of contrast-enhanced ultrasound (CEUS), has increased in recent years although few data are available about CEUS feasibility in the follow-up setting. The PseaAn study has been designed to assess the role of CEUS in the follow-up of abdominal trauma by defining its sensitivity, specificity and predictive values compared with abdominal CT scan. The PseAn study is a multi-centric international diagnostic cross-sectional study initiated by the Level I Trauma Center of the Niguarda Ca' Granda Hospital in Milan, Italy. To study the role of CEUS in detecting post-traumatic splenic, hepatic, and renal PAs compared with the gold standard of CT with intravenous contrast at different follow-up time points, and whether it can replace CT scan in the follow-up of solid organ injuries, patients with OIS III and above will undergo a follow-up with both a CEUS and CT scan to detect post-traumatic parenchymal pseudoaneurysm within two to five days from injury. The use of CEUS in the follow-up of abdominal trauma follow-up (particularly blunt trauma) has increased, to minimise the use of ionizing radiation and contrast media and encouraging results have been published during the last decade showing that CEUS is an accurate technique for evaluating traumatic lesions of solid abdominal organs. Conclusions We think that CEUS, which is underused worldwide, is a useful and safe tool that may replace CT scan in follow-up with the major advantage of reduced radiation. Our current study may give stronger evidence to support this view.

Follow-up strategies for patients with splenic trauma managed non-operatively: the 2022 World Society of Emergency Surgery consensus document

Background

In 2017, the World Society of Emergency Surgery published its guidelines for the management of adult and pediatric patients with splenic trauma. Several issues regarding the follow-up of patients with splenic injuries treated with NOM remained unsolved.

Methods

Using a modified Delphi method, we sought to explore ongoing areas of controversy in the NOM of splenic trauma and reach a consensus among a group of 48 international experts from five continents (Africa, Europe, Asia, Oceania, America) concerning optimal follow-up strategies in patients with splenic injuries treated with NOM.

Results

Consensus was reached on eleven clinical research questions and 28 recommendations with an agreement rate ≥ 80%. Mobilization after 24 h in low-grade splenic trauma patients (WSES Class I, AAST Grades I–II) was suggested, while in patients with high-grade splenic injuries (WSES Classes II–III, AAST Grades III–V), if no other contraindications to early mobilization exist, safe mobilization of the patient when three successive hemoglobins 8 h apart after the first are within 10% of each other was considered safe according to the panel. The panel suggests adult patients to be admitted to hospital for 1 day (for low-grade splenic injuries—WSES Class I, AAST Grades I–II) to 3 days (for high-grade splenic injuries—WSES Classes II–III, AAST Grades III–V), with those with high-grade injuries requiring admission to a monitored setting. In the absence of specific complications, the panel suggests DVT and VTE prophylaxis with LMWH to be started within 48–72 h from hospital admission. The panel suggests splenic artery embolization (SAE) as the first-line intervention in patients with hemodynamic stability and arterial blush on CT scan, irrespective of injury grade. Regarding patients with WSES Class II blunt splenic injuries (AAST Grade III) without contrast extravasation, a low threshold for SAE has been suggested in the presence of risk factors for NOM failure. The panel also suggested angiography and eventual SAE in all hemodynamically stable adult patients with WSES Class III injuries (AAST Grades IV–V), even in the absence of CT blush, especially when concomitant surgery that requires change of position is needed. Follow-up imaging with contrast-enhanced ultrasound/CT scan in 48–72 h post-admission of trauma in splenic injuries WSES Class II (AAST Grade III) or higher treated with NOM was considered the best strategy for timely detection of vascular complications.

Conclusion

This consensus document could help guide future prospective studies aiming at validating the suggested strategies through the implementation of prospective trauma databases and the subsequent production of internationally endorsed guidelines on the issue.

Deep learning for emergency ascites diagnosis using ultrasonography images

PURPOSE

The detection of abdominal free fluid or hemoperitoneum can provide critical information for clinical diagnosis and treatment, particularly in emergencies. This study investigates the use of deep learning (DL) for identifying peritoneal free fluid in ultrasonography (US) images of the abdominal cavity, which can help inexperienced physicians or non-professional people in diagnosis. It focuses specifically on first-response scenarios involving focused assessment with sonography for trauma (FAST) technique.

METHODS

A total of 2985 US images were collected from ascites patients treated from 1 January 2016 to 31 December 2017 at the Shenzhen Second People's Hospital. The data were categorized as Ascites-1, Ascites-2, or Ascites-3, based on the surrounding anatomy. A uniform standard for regions of interest (ROIs) and the lack of obstruction from acoustic shadow was used to classify positive samples. These images were then divided into training (90%) and test (10%) datasets to evaluate the performance of a U-net model, utilizing an encoder-decoder architecture and contracting and expansive paths, developed as part of the study.

RESULTS

Test results produced sensitivity and specificity values of 94.38% and 68.13%, respectively, in the diagnosis of Ascites-1 US images, with an average Dice coefficient of 0.65 (standard deviation [SD] = 0.21). Similarly, the sensitivity and specificity for Ascites-2 were 97.12% and 86.33%, respectively, with an average Dice coefficient of 0.79 (SD = 0.14). The accuracy and area under the curve (AUC) were 81.25% and 0.76 for Ascites-1 and 91.73% and 0.91 for Ascites-2.

CONCLUSION

The results produced by the U-net demonstrate the viability of DL for automated ascites diagnosis. This suggests the proposed technique could be highly valuable for improving FAST-based preliminary diagnoses, particularly in emergency scenarios.

Role of Contrast-Enhanced Ultrasound (CEUS) in Native Kidney Pathology: Limits and Fields of Action

Gray scale ultrasound has an important diagnostic role in native kidney disease. Low cost, absence of ionizing radiation and nephrotoxicity, short performance time, and repeatability even at the bedside, are the major advantages of this technique. The introduction of contrast enhancement ultrasound (CEUS) in daily clinical practice has significantly reduced the use of contrast enhancement computed tomography (CECT) and contrast enhancement magnetic resonance (CEMR), especially in patients with renal disease. Although there are many situations in which CECT and CEMRI are primarily indicated, their use may be limited by the administration of the contrast medium, which may involve a risk of renal function impairment, especially in the elderly, and in patients with acute kidney injury (AKI) and moderate to severe chronic kidney disease (CKD). In these cases, CEUS can be a valid diagnostic choice. To date, numerous publications have highlighted the role of CEUS in the study of parenchymal micro-vascularization and renal pathology by full integration with second level imaging methods (CECT and CEMRI) both in patients with normal renal function and with diseased kidneys. The aim of this review is to offer an updated overview of the limitations and potential applications of CEUS in native kidney disease.

Review of Multimodality Imaging of Renal Trauma

Blunt trauma accounts for more than 95% of traumatic renal injury and results from shear forces from rapid acceleration or deceleration and/or collision against the spine or ribs. The use of multiphasic contrast-enhanced computed tomography (CT) has proven pivotal in the evaluation and management of traumatic kidney injury, and CT imaging features provide the basis for nonsurgical staging. This article describes the epidemiology and mechanisms of blunt and penetrating traumatic renal injury and reviews the range of findings from various imaging modalities, with a particular emphasis on contrast-enhanced CT.

Contrast-enhanced ultrasonography (CEUS) in the follow-up of pediatric abdominal injuries: value and timing

AIMS

Primary aim was to investigate the value and safety of contrast-enhanced ultrasonography (CEUS) during follow-up (FU) of splenic, hepatic and renal post-traumatic injuries in a pediatric population. Secondary aim was to extrapolate appropriate timing of FU-CEUS.

METHODS

In a retrospective study, post-traumatic parenchymal injuries diagnosed with CT or CEUS, were subjected to non-operative management and followed with CEUS.

RESULTS

Forty-six patients were enrolled, with isolated or combined injuries, for a total of 30 splenic, 15 hepatic and 12 renal injuries. At admission 42/46 patients underwent CT and 4/46 underwent CEUS. During FU a total of 65 CEUS were performed: 16 within 72 h to check delayed active bleeding or parenchymal rupture; 24 between 5 and 10 days post admission, to pose indication to active mobilization or to discharge; 21 between 20 and 60 days post admission to document complete healing of the lesion or pose indication to discharge in most severe injuries. No complications related to CEUS were encountered.

CONCLUSIONS

CEUS is valuable and safe to follow patients with post-traumatic abdominal injuries, even if further data are needed for renal injuries. We propose a tailored approach based on injury grade and clinical course: in the first 3 days only in case of delayed bleeding or rupture suspect; between 5 and 10 days post trauma to ensure a safe active mobilization and/or pose indication to discharge, and over 20-30 days post trauma to pose indication to discharge in most severe injuries or document complete healing and permit return to sport activities.

Duodeno-pancreatic and extrahepatic biliary tree trauma: WSES-AAST guidelines

Duodeno-pancreatic and extrahepatic biliary tree injuries are rare in both adult and pediatric trauma patients, and due to their anatomical location, associated injuries are very common. Mortality is primarily related to associated injuries, but morbidity remains high even in isolated injuries. Optimal management of duodeno-bilio-pancreatic injuries is dictated primarily by hemodynamic stability, clinical presentation, and grade of injury. Endoscopic and percutaneous interventions have increased the ability to non-operatively manage these injuries. Late diagnosis and treatment are both associated to increased morbidity and mortality. Sequelae of late presentations of pancreatic injury and complications of severe pancreatic trauma are also increasingly addressed endoscopically and with interventional radiology procedures. However, for moderate and severe extrahepatic biliary and severe duodeno-pancreatic injuries, immediate operative intervention is preferred as associated injuries are frequent and commonly present with hemodynamic instability or peritonitis. The aim of this paper is to present the World Society of Emergency Surgery (WSES) and American Association for the Surgery of Trauma (AAST) duodenal, pancreatic, and extrahepatic biliary tree trauma management guidelines.

Kidney and uro-trauma: WSES-AAST guidelines

Renal and urogenital injuries occur in approximately 10-20% of abdominal trauma in adults and children. Optimal management should take into consideration the anatomic injury, the hemodynamic status, and the associated injuries. The management of urogenital trauma aims to restore homeostasis and normal physiology especially in pediatric patients where non-operative management is considered the gold standard. As with all traumatic conditions, the management of urogenital trauma should be multidisciplinary including urologists, interventional radiologists, and trauma surgeons, as well as emergency and ICU physicians. The aim of this paper is to present the World Society of Emergency Surgery (WSES) and the American Association for the Surgery of Trauma (AAST) kidney and urogenital trauma management guidelines.

Contrast-enhanced ultrasound (CEUS) in pediatric blunt abdominal trauma

Baseline ultrasound is the first-choice technique in traumatic hemodynamically stable children, and is essential in the early assessment of unstable patients to detect hemoperitoneum or other potentially fatal conditions. Despite the technological advancements in new ultrasound equipment and the experience of the operators, it is not always possible to rule out the presence of parenchymal traumatic lesions by means of baseline ultrasound nor to suspect them, especially in the absence of hemoperitoneum. For this reason, in the last decades, basic ultrasound has been associated with contrast-enhanced ultrasound (CEUS) to evaluate the stable little patient in cases such as low-energy blunt abdominal trauma. Because it relies on second-generation contrast agents, the CEUS technique allows for better detection of parenchymal injuries. CEUS has been demonstrated to be almost as sensitive as contrast-enhanced CT in the detection of traumatic injuries in patients affected by low-energy isolated abdominal trauma, with levels of sensitivity and specificity up to 95%. A very important point in favor of CEUS is its capacity to help distinguish the healthy patient, who can be discharged, from the one needing prolonged monitoring, operative management or hospitalization. Finally, we also have the ability to follow-up on low-grade traumatic lesions using CEUS, always keeping in mind patients' clinical conditions and their hemodynamics.

Emergency and critical care applications for contrast-enhanced ultrasound

INTRODUCTION

Contrast-enhanced ultrasound (CEUS) using intravascular microbubbles has potential to revolutionize point-of-care ultrasonography by expanding the use of ultrasonography into clinical scenarios previously reserved for computed tomography (CT), magnetic resonance imaging, or angiography.

METHODS

We performed a literature search and report clinical experience to provide an introduction to CEUS and describe its current applications for point-of-care indications.

RESULTS

The uses of CEUS include several applications highly relevant for emergency medicine, such as solid-organ injuries, actively bleeding hematomas, or abdominal aortic aneurysms. Compared with CT as the preeminent advanced imaging modality in the emergency department, CEUS is low cost, radiation sparing, repeatable, and readily available. It does not require sedation, preprocedural laboratory assessment, or transportation to the radiology suite.

CONCLUSIONS

CEUS is a promising imaging technique for point-of-care applications in pediatric and adult patients and can be applied for patients with allergy to CT contrast medium or with impaired renal function. More high-quality CEUS research focusing on accuracy, patient safety, health care costs, and throughput times is needed to validate its use in emergency and critical care settings.

Contrast-enhanced ultrasound (CEUS) of the abdominal vasculature

Vascular diseases account for a significant proportion of abdominal pathology and represent a common referral source for abdominal ultrasonographic examinations. B-mode, color Doppler, and spectral Doppler analyses are well-established in the evaluation of abdominal blood vessels although they may occasionally be limited by lower sensitivity for slow flow visualization or the deeper location of abdominal vascular structures. The introduction of microbubbles as ultrasonographic contrast agents has rendered contrast-enhanced ultrasound (CEUS), a valuable complementary ultrasonographic technique, which is capable of addressing clinically significant problems and guiding patient management. The purpose of this pictorial review is to analyze the use of CEUS in the evaluation of abdominal vascular pathology and illustrate such applications by presenting representative images. Pathology discussed includes abdominal aortic aneurysm, post-endovascular treatment aorta, portal vein thrombosis, abdominal vascular trauma, and organ transplantation along with its complications.

Follow-Up Imaging in Patients with Blunt Splenic or Hepatic Injury Managed Nonoperatively

Nonoperative management of blunt splenic and hepatic injuries has become the standard of care for hemodynamically stable patients. However, nonoperative management may lead to delayed complications and appropriate follow-up is therefore crucial. The aim of this systematic literature review was to assess the role of different imaging modalities in the follow-up assessment of patients with blunt splenic or hepatic injuries using the PubMed database. Eighteen studies were found to be relevant to the topic. A total of 2725 patients were enrolled in the included studies. Both retrospective and prospective studies, but no randomized controlled trials were found. In these studies, CT, ultrasound, and contrast-enhanced ultrasound were discussed. CT was the most commonly used imaging modality. Taking into account all studies included, only one patient underwent intervention due to a complication diagnosed by follow-up CTscan in the absence of clinical signs and symptoms. This equates to a total of 920 CT scans performed to diagnose one clinically nonevident complication that required intervention. Based on the reviewed literature, routine imaging follow-up CT scans may not be indicated in asymptomatic patients with lower grade blunt splenic or hepatic injuries. Contrast-enhanced ultrasound is a promising alternative imaging modality for the follow-up of these patients.

Diagnostic accuracy of contrast enhanced ultrasound in patients with blunt abdominal trauma presenting to the emergency department: a systematic review and meta-analysis

We aimed to investigate the diagnostic accuracy of contrast-enhanced ultrasound (CEUS) in evaluating blunt abdominal trauma for patients presenting to the emergency department. Electronic search of Scopus and Pubmed was performed from inception to September 2016. Human studies investigating the diagnostic accuracy of CEUS in identifying abdominal solid organ injuries were included. Risk of bias was assessed using the QUADAS tool. A total of 10 studies were included in the study and 9 of them were included for meta-analysis. The log(DOR) values ranged from 3.80 (95% CI: 2.81-4.79) to 8.52 (95% CI: 4.58-12.47) in component studies. The combined log(DOR) was 6.56 (95% CI: 5.66-7.45). The Cochran's Q was 11.265 (p = 0.793 with 16 degrees of freedom), and the Higgins' I² was 0%. The CEUS had a sensitivity of 0.981 (95% CI: 0.868-0.950) and a false positive rate of 0.018 (95% CI: 0.010-0.032) for identifying parenchymal injuries, with an AUC of 0.984. CEUS performed at emergency department had good diagnostic accuracy in identifying abdominal solid organ injuries. CEUS can be recommended in monitoring solid organ injuries, especially for patients managed with non-operative strategy.

Clinical Applications of Contrast-Enhanced Ultrasound in the Pediatric Work-Up of Focal Liver Lesions and Blunt Abdominal Trauma: A Systematic Review

In pediatrics ultrasound has long been viewed more favorably than imaging that exposes patients to radiation and iodinated contrast or requires sedation. It is child-friendly and diagnostic capabilities have been improved with the advent of contrast-enhanced ultrasound (CEUS). The application of CEUS is indeed promising. However, no ultrasound contrast agent manufactured today is registered for pediatric use in Europe. The contrast agent SonoVue^® has recently been approved by the FDA under the name of Lumason^® to be used in hepatic investigations in adults and children. This article reviews the literature with respect to 2 specific applications of CEUS in children: 1) identification of parenchymal injuries following blunt abdominal trauma, and 2) classification of focal liver lesions. Applications were chosen through the CEUS guidelines published by the European Federation of Societies for Ultrasound in Medicine and Biology and World Federation for Ultrasound in Medicine and Biology. Literature was obtained by searching Medline and Pubmed Central (using Pubmed), Scopus database and Embase. CEUS proved to be an effective investigation in the hemodynamically stable child for identifying parenchymal injuries and for the characterization of focal liver lesions. CEUS showed comparable performance to CT and MRI with a specificity of 98% for identifying benign lesions and a negative predictive value of 100%. For the applications reviewed here, CEUS holds promising perspectives and can help reduce radiation exposure and use of iodinated contrast agents in pediatrics, thereby potentially reducing complications in routine imaging.

Abdominal Trauma Evaluation for the Pediatric Surgeon

Trauma is the leading cause of pediatric mortality and abdominal injury is a significant contributor to morbidity. The assessment of abdominal trauma in children must be conducted expeditiously and thoroughly. Physical examination, laboratory testing, and imaging are central to trauma evaluation. In children with minor injury, protocols may help to limit the use of ionizing radiation. Children with significant abdominal injury who are unstable should be resuscitated with blood products and undergo emergent surgical intervention.

Pediatric adrenal trauma: evaluation and follow-up with contrast-enhanced ultrasound (CEUS)

Adrenal trauma is rarely encountered in the pediatric population, often as a component of multi-organ injury and often presenting with hematoma formation. Contrast-enhanced computed tomography (CECT) is the established imaging modality both for initial evaluation and follow-up of patients with blunt abdominal trauma. In children, radiation exposure should be minimized and alternative imaging strategies are needed. Contrast-enhanced ultrasound (CEUS) has recently been successfully used for evaluation of patients with hepatic, renal and splenic injury. We present three cases of children with post-traumatic adrenal hematomas, which were initially diagnosed with CECT and subsequently followed up with CEUS, suggesting that CEUS may be considered for follow-up of adrenal injuries in children. CEUS improves the diagnostic capabilities by increasing tissue contrast and spatial resolution, readily differentiating viable from necrotic tissue in comparison to conventional ultrasound without the risk of iodine contrast agents and ionizing radiation of repeated CECT examinations.

Blunt pancreatic trauma: A persistent diagnostic conundrum?

Blunt pancreatic trauma is an uncommon injury but has high morbidity and mortality. In modern era of trauma care, pancreatic trauma remains a persistent challenge to radiologists and surgeons alike. Early detection of pancreatic trauma is essential to prevent subsequent complications. However early pancreatic injury is often subtle on computed tomography (CT) and can be missed unless specifically looked for. Signs of pancreatic injury on CT include laceration, transection, bulky pancreas, heterogeneous enhancement, peripancreatic fluid and signs of pancreatitis. Pan-creatic ductal injury is a vital decision-making parameter as ductal injury is an indication for laparotomy. While lacerations involving more than half of pancreatic parenchyma are suggestive of ductal injury on CT, ductal injuries can be directly assessed on magnetic resonance imaging (MRI) or encoscopic retrograde cholangio-pancreatography. Pancreatic trauma also shows temporal evolution with increase in extent of injury with time. Hence early CT scans may underestimate the extent of injures and sequential imaging with CT or MRI is important in pancreatic trauma. Sequential imaging is also needed for successful non-operative management of pancreatic injury. Accurate early detection on initial CT and adopting a multimodality and sequential imaging strategy can improve outcome in pancreatic trauma.

Contrast-enhanced sonography for the identification of benign and malignant thyroid nodules: Systematic review and meta-analysis

PURPOSE

The use of contrast-enhanced sonography (CEUS) has yielded promising results in the differentiation of thyroid nodules. We conducted this meta-analysis to assess its performance in identifying and distinguishing between benign and malignant thyroid nodules.

METHODS

PubMed, Medline, Embase, and the Cochrane Library were searched for studies published through the end of December 2013. Sensitivity, specificity, positive and negative likelihood ratios, diagnostic odds ratio, and area under the curve were calculated.

RESULTS

A total of 13 studies were included in this meta-analysis. For the diagnosis of malignant thyroid nodules worldwide, the overall mean rates of sensitivity and specificity of CEUS were 90% (95% confidence interval [CI], 88-93%) and 86% (95% CI, 83-89%), respectively. The summary diagnostic odds ratio was 52.83 (95% CI, 21.71-128.55), and the area under the curve for the summary receiver operating characteristic curve was 0.94 (95% CI, 0.90-0.98).

CONCLUSIONS

This meta-analysis indicates that CEUS may be a valuable supplemental method, with high rates of sensitivity and specificity, to use for identifying and distinguishing between benign and malignant thyroid nodules.

Role of US Contrast Agents in the Assessment of Indeterminate Solid and Cystic Lesions in Native and Transplant Kidneys

Ultrasonography (US) is often the initial imaging modality employed in the evaluation of renal diseases. Despite improvements in B-mode and Doppler imaging, US still faces limitations in the assessment of focal renal masses and complex cysts as well as the microcirculation. The applications of contrast-enhanced US (CEUS) in the kidneys have dramatically increased to overcome these shortcomings with guidelines underlining their importance. This article describes microbubble contrast agents and their role in renal imaging. Microbubble contrast agents consist of a low solubility complex gas surrounded by a phospholipid shell. Microbubbles are extremely safe and well-tolerated pure intravascular agents that can be used in renal failure and obstruction, where computed tomographic (CT) and magnetic resonance (MR) imaging contrast agents may have deleterious effects. Their intravascular distribution allows for quantitative perfusion analysis of the microcirculation, diagnosis of vascular problems, and qualitative assessment of tumor vascularity and enhancement patterns. Low acoustic power real-time prolonged imaging can be performed without exposure to ionizing radiation and at lower cost than CT or MR imaging. CEUS can accurately distinguish pseudotumors from true tumors. CEUS has been shown to be more accurate than unenhanced US and rivals contrast material-enhanced CT in the diagnosis of malignancy in complex cystic renal lesions and can upstage the Bosniak category. CEUS can demonstrate specific enhancement patterns allowing the differentiation of benign and malignant solid tumors as well as focal inflammatory lesions. In conclusion, CEUS is useful in the characterization of indeterminate renal masses and cysts.

Comparison between MRI and CEUS in the follow-up of patients with blunt abdominal trauma managed conservatively

INTRODUCTION

Over the past two decades, there has been a shift toward non-operative treatment of patients undergoing a solid organ injury, thus requiring an increasing number of imaging studies to monitor the healing of lesions, which were performed by computed tomography (CT). In consideration of the use of ionizing radiation and contrast media, nowadays there is a trend toward the use contrast-enhanced ultrasound (CEUS) in the follow-up of blunt abdominal trauma. However CEUS has some limits, especially in the assessments of small lesions and in the evaluation of urinary tract lesions and vascular complications. Magnetic resonance imaging (MRI) is a useful alternative, since its lack of use of ionizing radiation, its panoramicity, the possibility to avoid contrast media and the ability to properly evaluate even small lesions. The aim of this study is to evaluate the usefulness and the feasibility of MRI in the follow-up of patients with low-grade blunt abdominal trauma.

MATERIALS AND METHODS

We performed a retrospective review of a cohort including 270 consecutive patients with a history of blunt abdominal trauma; among them, 118 underwent a high-energy trauma, and 152 a low-energy trauma. 124 patients had findings of abdominal injuries at the contrast-enhanced multidetector CT (CE-MDCT), including 68 from the group of major trauma and 56 from the group of minor trauma. 39 patients were operated for incoming lesions. The remaining 85 patients were treated conservatively. Eight patients underwent surgery later for delayed bleeding. The remaining 77 underwent the full follow-up protocol. Follow-up protocol included CEUS at 24 and 72 h and CEUS and MRI at 1 month after trauma; only MRI was performed until the complete resolution.

RESULTS

CEUS at 24-h and at 72-h from trauma showed a very good correlation with onset CE-MDCT in lesions staging. With respect to onset CE-MDCT, CEUS did not identified 2 adrenal injuries and 2 lesions of urinary tract, an intrinsic limit of this technique. CEUS performed at 1 month did not show traumatic lesions in 49/77 of patients. In the remaining 28/77 cases, CEUS demonstrated reduction of the size of the lesions ranging from 25 to 50%. MRI performed at 1 month from trauma did not show traumatic injuries in 37/77 patients; it demonstrated persistence of organ lesion in 40/77 patients. Therefore, in 12/77 patients MRI performed at 1-month demonstrated the persistence of minimal or moderate organ injury, while CEUS was completely negative. In addition, MRI allowed to enhance the persistence of adrenal lesions in 2 cases and the integrity of urinary tract in 2. In the remaining 28 patients, in which both CEUS and MRI showed disease persistence, MRI, however, allowed a better definition of injury extension with respect to CEUS, in terms of dimensions, edges, and morphological evolution.

DISCUSSION AND CONCLUSIONS

MRI allowed to make a better assessment of injuries than CEUS, allowing also a temporal stage of lesions. Infact, there are different evolution stages corresponding to accurate imaging findings. To our knowledge, this is the first study that describes the evolution of blood collection in parenchymal abdominal organs. Therefore, in patients who underwent abdominal traumatic injuries conservatively treated, the follow-up at 1 month can be made by MRI, due to its panoramicity and its high contrast resolution, which allow a better morphological and temporal trauma staging respect to the CEUS.

Contrast-enhanced ultrasound (CEUS) in nephrology: Has the time come for its widespread use?

Grey-scale ultrasound has an important diagnostic role in nephrology. The absence of ionizing radiations and nephrotoxicity, rapidity of execution, excellent repeatability, the possibility to perform the test at the patient's bed and the low cost represent important advantages of this technique. Paired with real-time sonography and colour-power-Doppler contrast-enhanced ultrasound (CEUS) reduces the diagnostic gap with computed tomography (CT) and magnetic resonance (MR) and represents a major step in the evolution of clinical ultrasound. Although there are several situations in which contrast-enhanced CT and MR are indicated (i.e. evaluation of cystic or ischemic lesions, traumatisms and ablative therapies of the native and transplanted kidney), the use of CT contrast media presents a high risk of contrast-induced nephropathy (i.e. in elderly people, subjects with comorbidities and those with renal dysfunction), while gadolinium-based RM contrast agents are contraindicated for the risk of nephrogenic systemic fibrosis (i.e. in patients with severe renal dysfunction). In these situations, CEUS may be a viable alternative, however, as any technique associated with the infusion of pharmacological substances, the potential advantages and risks of CEUS should be critically evaluated. In this regard, the European Federation of Societies for Ultrasound in Medicine and Biology (EFSUMB) has published the guidelines for the use of CEUS for the kidney imaging and the International Contrast Ultrasound Society (ICUS) has been recently founded. The aim of this review is to offer an updated overview of the potential applications of CEUS in nephrology, reporting some indications and possible risks associated to its use.

The role of CEUS in the assessment of haemodynamically stable patients with blunt abdominal trauma

Computed tomography (CT) still represents the preferred imaging method in the assessment of patients presenting with multiple trauma. Nevertheless, in patients with low-energy abdominal trauma, the use of CT is debated because of the possible unnecessary radiation exposure. Accordingly, conventional ultrasound (US) imaging has been increasingly employed as the initial imaging modality in the workup of minor traumatic emergency conditions. Focused assessment with sonography for trauma is widely used to detect free intra-abdominal fluid, but its role is controversial, because the absence of free fluid does not exclude the presence of injuries to abdominal organ. Injection of an ultrasound contrast agent (UCA) may give the radiologist relevant additional information to that obtained with conventional US. Thus, in trauma patients, following early assessment with conventional US imaging, a contrast-enhanced US (CEUS) can provide a more reliable evaluation of solid organ injuries and related vascular complications, including active bleeding, pseudoaneurysms, and artero-venous fistulas. CEUS cannot replace abdominal CT, but it represents a noninvasive and repeatable imaging tool capable of providing a reliable assessment of trauma severity and expedite the patient's treatment.

Effectiveness of contrast-enhanced ultrasound in the classification and emergency management of abdominal trauma

OBJECTIVE

To analyse the correlation between contrast-enhanced ultrasound (CEUS)-based classification of the severity of abdominal parenchymal organ trauma and clinical outcomes, and to explore CEUS in classifying patients with such trauma, expecting that the use of CEUS will potentially enhance the quality and speed of the emergency management of abdominal trauma.

METHODS

Three hundred six consecutive patients with blunt abdominal parenchymal organ trauma who received CEUS examination were retrospectively analysed. Two CEUS radiologists (identified as Reader A and Reader B in this study) who were not involved in the CEUS examinations of the patients were then asked to classify the patients independently according to their CEUS results. The classification results were later compared with patients' clinical outcomes using Spearman's rank correlation.

RESULTS

The final clinical outcomes showed that 25.5 % (78/306) of patients received conservative treatment, 52.0 % (159/306) received minimally invasive treatment, and 22.5 % (69/306) received surgery. Spearman's rank correlation coefficients between the CEUS-based classification and clinical outcome were 0.952 from Reader A and 0.960 from Reader B.

CONCLUSIONS

CEUS can play an important role in the emergency management of abdominal trauma through the classification of patients for different treatment methods.

KEY POINTS

• The severity of abdominal trauma was classified by contrast-enhanced ultrasound (CEUS) • There was a high correlation between CEUS-based classification and clinical outcomes • CEUS-based classification is helpful for surgeons in the emergency management of abdominal trauma.

Blunt abdominal trauma: role of contrast-enhanced ultrasound (CEUS) in the detection and staging of abdominal traumatic lesions compared to US and CE-MDCT

PURPOSE

This study was undertaken to evaluate the accuracy of contrast-enhanced ultrasound (CEUS) in the detection and grading of abdominal traumatic lesions in patients with low-energy isolated abdominal trauma in comparison with baseline ultrasound (US) and contrast-enhanced multidetector computed tomography (CE-MDCT), considered the gold standard.

MATERIALS AND METHODS

A total of 256 consecutive patients who arrived in our Emergency Department between January 2006 and December 2012 (159 males and 97 females aged 7-82 years; mean age 41 years), with a history of low-energy isolated abdominal trauma were retrospectively analysed. All patients underwent US, CEUS with the use of a second-generation contrast agent (Sonovue, Bracco, Milan, Italy) and MDCT. Sensitivity, specificity, positive and negative predictive values (PPV and NPV) and overall accuracy for the detection of lesions and free peritoneal fluid on US and CEUS, and sensitivity for the grading of lesions on CEUS were calculated compared with the CT findings, in accordance with the American Association for the Surgery of Trauma criteria.

RESULTS

CE-MDCT identified 84 abdominal traumatic lesions (liver = 28, spleen = 35, kidney = 21) and 45 cases of free intraperitoneal fluid. US depicted 50/84 traumatic lesions and 41/45 cases of free peritoneal fluid; CEUS identified 81/84 traumatic lesions and 41/45 free peritoneal fluid. The sensitivity, specificity, PPV, NPV and overall accuracy for the identification of traumatic abdominal lesions were 59, 99, 98, 83 and 86 %, respectively, for US and 96, 99, 98, 98 and 98 %, respectively, for CEUS. The values for the identification of haemoperitoneum were 91, 99, 95, 98 and 97 %, respectively, for US and 95, 99, 95, 99 and 98 %, respectively, for CEUS. CEUS successfully staged 72/81 traumatic lesions with a sensitivity of 88 %.

CONCLUSIONS

In patients with low-energy isolated abdominal trauma US should be replaced by CEUS as the first-line approach, as it shows a high sensitivity both in lesion detection and grading. CE-MDCT must always be performed in CEUS-positive patients to exclude active bleeding and urinomas.

Emergency contrast-enhanced ultrasonography for pancreatic injuries in blunt abdominal trauma

PURPOSE

The purpose of this study was to retrospectively investigate the application of emergency contrast-enhanced ultrasonography (CEUS) in blunt pancreatic trauma.

MATERIALS AND METHODS

Twenty-two consecutive patients with blunt pancreatic trauma were examined using CEUS from March 2007 to June 2012. The findings of CEUS were compared with those of contrast-enhanced computed tomography scans at level-1 diagnostic tests.

RESULTS

Out of the 22 patients, 21 were diagnosed with blunt pancreatic injury using CEUS, including 8 patients with lesions in the neck of pancreas, 9 in the body, 3 in the tail and 1 in the head. The injury sites appeared as anechoic and/or hypoechoic perfusion defect regions with irregular borders in parenchyma and capsule on CEUS images. The lesion sizes measured by CEUS were 1.88 ± 0.81 cm, which were consistent with the 1.93 ± 0.77 cm measured by CT (p > 0.05). Using CT as a reference standard, the detection rate of CEUS in blunt pancreatic trauma was 95.5 % (21/22).

CONCLUSIONS

CEUS findings can be used to provide a reliable diagnosis for blunt pancreatic trauma. CEUS is thus promising in the assessment of blunt pancreatic trauma, especially in institutions where emergency CEUS is used as an initial diagnostic instrument.

Contrast enhanced ultrasound of the kidneys: what is it capable of?

One of the many imaging uses of contrast enhanced ultrasound (CEUS) is studying a wide variety of kidney pathology, due to its ability to detect microvascular blood flow in real time without affecting renal function. CEUS enables dynamic assessment and quantification of microvascularisation up to capillary perfusion. The objective of this paper is to briefly refresh basic knowledge of ultrasound (US) contrast agents' physical properties, to study technical details of CEUS scanning in the kidneys, and to review the commonest renal indications for CEUS, with imaging examples in comparison to baseline unenhanced US and computed tomography when performed. Safety matters and limitations of CEUS of the kidneys are also discussed.

The use of contrast-enhanced ultrasound for the evaluation of solid abdominal organ injury in patients with blunt abdominal trauma

BACKGROUND

The evaluation and management of blunt abdominal trauma is primarily nonoperative. Previous attempts to identify parenchymal solid-organ injury with sonography have been unsatisfactory. The use of Perflutren Lipid Microsphere (Definity) contrast-enhanced ultrasound (DUS) may provide an additional modality for evaluation of solid-organ injury with decreased risk of radiation exposure and contrast-related complications.

METHODS

Injured patients admitted to a state-designated Level I trauma center (January 2008 to July 2009), who showed evidence of solid-organ injury after blunt abdominal trauma on initial computed tomography (CT) were eligible for entry into the study. Patients underwent DUS examinations within 12 hours of initial CT. Ultrasound images were then compared with findings of CT for organ location, size, and grade of injury.

RESULTS

Twenty patients with evidence of solid-organ injury on CT were evaluated with DUS. DUS correctly identified five of eight liver lesions, with a sensitivity of 62.5%. DUS correctly identified all nine splenic lesions demonstrating a sensitivity of 100%. DUS correctly identified one of two kidney injuries, demonstrating a sensitivity of 50%. Overall, the positive predictive value for all solid-organ injuries was 100%, with negative predictive value of 20%. The overall sensitivity for DUS was 79% (15 of 19 patients), and specificity was 100% (15 of 15 patients).

CONCLUSION

Contrast-enhanced sonography is a potential new modality for the evaluation of solid-organ injury for patients with blunt abdominal trauma. With further research, DUS may provide a safe and accurate alternative to CT.

LEVEL OF EVIDENCE

Diagnostic study, level IV.

Contrast-enhanced ultrasound performed under urgent conditions. Indications, review of the technique, clinical examples and limitations

Contrast-enhanced ultrasound (CEUS) is an imaging technique with various indications, most of which refer to scheduled examinations. However, CEUS can also be performed under urgent conditions for the investigation of many different clinical questions. This article reviews basic physics of ultrasound contrast agents and examines the commonest urgent clinical applications of CEUS. These include, among others, abdominal solid organ trauma and infarcts, scrotal and penile pathology and blood vessel imaging. Patients can be examined with a very short time delay at their bedside, without exposure to ionising radiation or risk of anaphylactic reaction and renal failure, while contraindications are minimal. CEUS technique is described for various urgent indications and imaging examples from our department's experience are presented. Safety matters and limitations of CEUS are also mentioned. Teaching Points • Contrast-enhanced ultrasound (CEUS) can be performed urgently for various clinical applications. • Abdominal indications include solid organ trauma and infarcts. • CEUS in abdominal organ trauma correlates well with CT and can replace it for patient follow-up. • CEUS images testicular torsion, infection and infarction, as well as testicular and penile trauma. • Blood vessels can be assessed with CEUS for obstruction, aneurysm, thrombosis and dissection.

Influences on the amount of intraperitoneal haemorrhage after blunt liver injury: a retrospective autopsy study

OBJECTIVE

The amount of intraperitoneal blood loss due to traumatic liver injury is rarely addressed in correlation with concomitant injuries or pre-existing liver disease.

METHODS

We carried out a retrospective review of autopsy reports from 1995 until 2007 at the Institute of Forensic Medicine (Bern, Switzerland), and evaluated 126 cases of blunt liver trauma for the amount of blood in the abdominal cavity, severity of liver injury, pre-existing liver disease and concomitant injuries.

RESULTS

Grades IV and V liver injuries (American Association for the Surgery of Trauma classification) showed greater blood loss than grades I and II liver injuries. Grade III liver injuries showed no significant difference in the amount of intraperitoneal blood compared with grades IV and V liver injuries and 53 cases of liver injuries (42%) did not bleed at all. The amount of blood found in the abdominal cavity ranged from 0 to 4500 ml. Pre-existing liver steatosis showed no significant difference in injury pattern or bleeding from the liver. Three cases with liver haemangiomas and one with a liver cyst showed no lesion to their focal alteration. Because of the small number of cases, no statistical analysis was made concerning concomitant injuries such as head, thoracic or limb trauma.

CONCLUSION

Higher grades of liver injury severity are associated with higher blood loss into the abdominal cavity. In addition, a patient with pre-existing liver steatosis seems not to be at any greater risk of having a larger rupture or having stronger bleeding from the liver after a blunt impact compared with a patient with a normal liver.

Blunt abdominal trauma in children

PURPOSE OF REVIEW

This review will examine the current evidence regarding pediatric blunt abdominal trauma and the physical exam findings, laboratory values, and radiographic imaging associated with the diagnosis of intra-abdominal injuries (IAI), as well as review the current literature on pediatric hollow viscus injuries and emergency department disposition after diagnosis.

RECENT FINDINGS

The importance of the seat belt sign on physical examination and screening laboratory data remains controversial, although screening hepatic enzymes are recommended in the evaluation of nonaccidental trauma to identify occult abdominal organ injuries. Focused Assessment with Sonography for Trauma (FAST) has modest sensitivity for hemoperitoneum and IAI in the pediatric trauma patient. Patients with concern for undiagnosed IAI, including bowel injury, may be considered for hospital admission and serial abdominal exams without an increased risk of complications, if an exploratory laparotomy is not performed emergently.

SUMMARY

Although the FAST exam is not recommended as the sole screening tool to rule out IAI in hemodynamically stable trauma patients, it may be used in conjunction with the physical exam and laboratory findings to identify children at risk for IAI. Children with a normal physical exam and normal abdominal CT may not require routine hospitalization after blunt abdominal trauma.

Splenic trauma: what is new?

Evaluation for splenic injury is an important component of patient assessment after blunt abdominal trauma. Key imaging modalities include ultrasound, particularly for rapid identification of hemoperitoneum, and computed tomography (CT), which permits a more detailed and accurate determination of splenic integrity. Specific findings at contrast-enhanced multidetector CT (MDCT) should prompt the consideration of catheter angiography with arterial embolization as an adjunct to nonsurgical management. This article reviews the roles of imaging in the management of splenic trauma, illustrates the MDCT appearance of various splenic injuries, and discusses imaging-based indications for operative and angiographic intervention.

Contrast-enhanced sonography in blunt scrotal trauma()

The scope of this study was to determine whether contrast-enhanced ultrasonography (CEUS), compared with basic US, can increase diagnostic confidence and provide relevant information on blunt scrotal trauma. Over a period of 75 months we examined 40 patients seen consecutively for blunt scrotal trauma using high-resolution US, color-power Doppler, low mechanical index CEUS, and power Doppler after IV administration of contrast medium (SonoVue(®)). In the 24 cases that were positive, concordance between basal US and CEUS findings was grade 0 (absent) in 4 cases, grade 1 (low) in 3, grade 2 (moderate) in 8, and grade 3 (high) in 9. The relevance of the additional information provided by CEUS was classified as follows: high in 4/40 (10%), moderate 7/40 (17,5%), low 13/40 (32,5%), none in 14/40 (35%). Our findings demonstrate that CEUS is appreciably more sensitive in detecting damage caused by blunt scrotal trauma, particularly small lesions. It is also useful for differential diagnosis and marginalization of corpuscular fluid collections, fractures, and above all ruptures, which require immediate surgery. In our series 2 out of 3 (67%) patients with testicular rupture were diagnosed only by CEUS. We feel that the use of CEUS can significantly improve diagnostic confidence in cases of closed scrotal trauma although these conclusions need to be confirmed in larger case series.

The current role of contrast-enhanced ultrasound (CEUS) imaging in the evaluation of renal pathology

BACKGROUND

By using a microbubble contrast agent and contrast-specific imaging software, the contrast-enhanced ultrasound (CEUS) is able to depict the micro and macrocirculation of the target organ.

METHODS

A review of the peer reviewed literature was done regarding the current role of ultrasound CEUS imaging in the evaluation of renal pathology with reference to the diagnosis of renal ischaemia, in the characterization of complex cystic lesions and in those with equivocal enhancement at CT.

RESULTS

CEUS provides information on tissue perfusion and may play a role in kidney mass characterization similar to the role of contrast-enhanced CT and MRI. In this context, the characterization of cystic lesions is probably the most consolidated field of application of contrast agents on kidney ultrasound imaging. Finally, CEUS provides a good alternative to CT, especially in patients with contraindications to iodinated contrast agents.

CONCLUSIONS

The usefulness of CEUS in these applications is confirmed by extensive literature production and this article focuses on the potential clinical applications of recent advances in CEUS technology in urology.

Contrast-enhanced ultrasound imaging of active bleeding associated with hepatic and splenic trauma

PURPOSE

The aim of this study was to evaluate contrast-enhanced ultrasound (CEUS) imaging of active bleeding from hepatic and splenic trauma.

MATERIALS AND METHODS

Three hundred and ninety-two patients with liver or/and spleen trauma (179 liver and 217 spleen injuries), who underwent CEUS examinations following contrast-enhanced computed tomography (CT), were enrolled in this retrospective study over a period of >4 years. CEUS detected contrast medium extravasation or pooling in 16% (63/396) of liver or spleen lesions in 61 patients, which was confirmed by contrast-enhanced CT. Special attention was paid to observing the presence, location, and characteristics of the extravasated or pooled contrast medium.

RESULTS

The CEUS detection rate for active bleeding was not different from that of contrast-enhanced CT (p=0.333). Information from surgery, minimally invasive treatment and conservative treatment was used as reference standard, and the sensitivities of the two techniques were not different (p=0.122). Of 63 lesions in 61 patients, CEUS showed that 74.6% (47/63) (21 liver lesions and 26 spleen lesions) presented contrast medium extravasation or pooling, both in the organ and out the capsule, in 14.3% (9/63) and only outside the capsule in 11.1% (7/63). CEUS imaging of active bleeding from hepatic and splenic trauma presented various characteristics, and the sizes and shapes of the active bleeding due to contrast medium extravasation or pooling were variable.

CONCLUSIONS

CEUS can show the active bleeding associated with hepatic and splenic trauma with various imaging characteristics, thus making it possible to diagnose active bleeding using CEUS.

The role of arterial embolization in blunt splenic injury

PURPOSE

The aim of study was to evaluate the results of our experience with transarterial embolization based on a modified algorithm in patients with splenic injury.

MATERIALS AND METHODS

We collected data of patients admitted to our hospital from January 2006 to August 2008 for blunt splenic injury. During this period, 46 patients were admitted for splenic trauma, of whom 17 were treated surgically, 15 conservatively and 14 with percutaneous embolisation (13 men, mean age 44.8, mean injury severity score 18.5, six with grade IV and eight with contrast blush). Patients in shock were referred for laparotomy and splenectomy, whereas those who were haemodynamically stable or responsive to fluid resuscitation were further evaluated with computed tomography (CT). In the presence of imaging evidence of splenic injury ranging from grade I to grade III (n=15) a conservative approach was adopted, whereas haemodynamically unstable patients with grade V injury (n=17) were treated with splenectomy. Embolisation was performed in 14 patients with grade IV injury or in the event of contrast extravasation, regardless of injury grade. In patients with diffuse organ damage, we embolised the main splenic artery, whereas in the case of localised injury, embolisation was selective.

RESULTS

Proximal embolization was required in eight cases and distal coil embolization in six. In 13 cases, we placed magnetic-resonance-compatible coils 4-6 mm in diameter; only one patient was treated with gel-foam injection. Immediate technical success was achieved in all cases. In 13/14 patients (92.9%), no periprocedural complications were observed, whereas the remaining patient underwent splenectomy within 24 h due to recurrent bleeding.

CONCLUSIONS

On the basis of our algorithm, it is possible to reach a quick decision on the most appropriate treatment for patients presenting with blunt abdominal trauma, and splenic artery embolization seems to offer a reliable option in those with high-grade splenic injury or active bleeding.

Contrast-enhanced ultrasound: The evolving applications

Contrast-enhanced ultrasound (CEUS) is a major breakthrough for ultrasound imaging in recent years. By using a microbubble contrast agent and contrast-specific imaging software, CEUS is able to depict the micro- and macro-circulation of the targeted organ, which in turn leads to improved performance in diagnosis. Due to the special dual blood supply system in the liver, CEUS is particularly suitable for liver imaging. It is evident that CEUS facilitates improvement for characterization of focal liver lesions (FLLs), detection of liver malignancy, guidance for interventional procedures, and evaluation of treatment response after local therapies. CEUS has been demonstrated to be equal to contrast-enhanced computed tomography or magnetic resonance imaging for the characterization of FLLs. In addition, the applicability of CEUS has expanded to non-liver structures such as gallbladder, bile duct, pancreas, kidney, spleen, breast, thyroid, and prostate. The usefulness of CEUS in these applications is confirmed by extensive literature production. Novel applications include detecting bleeding sites and hematomas in patients with abdominal trauma, guiding percutaneous injection therapy and therefore achieving the goal of using interventional ultrasonography in managing splenic trauma, assessing the activity of Crohn’s disease, and detecting suspected endoleaks after endovascular abdominal aneurysm repair. Contrast-enhanced intraoperative ultrasound (US) and intracavitary use of CEUS have been developed and clinically studied. The potential use of CEUS involves sentinel lymph node detection, drug or gene delivery, and molecular imaging. In conclusion, the advent of CEUS has greatly enhanced the usefulness of US and even changed the status of US in clinical practice. The application of CEUS in the clinic is continuously evolving and it is expected that its use will be expanded further in the future.