Imaging of paediatric splenic injury with contrast-enhanced ultrasonography

Contrast-enhanced ultrasound: a comprehensive review of safety in children

Contrast-enhanced ultrasound (CEUS) has been increasingly used in pediatric radiology practice worldwide. For nearly two decades, CEUS applications have been performed with the off-label use of gas-containing second-generation ultrasound contrast agents (UCAs). Since 2016, the United States Food and Drug Administration (FDA) has approved the UCA Lumason for three pediatric indications: the evaluation of focal liver lesions and echocardiography via intravenous administration and the assessment of vesicoureteral reflux via intravesical application (contrast-enhanced voiding urosonography, ceVUS). Prior to the FDA approval of Lumason, numerous studies with the use of second-generation UCAs had been conducted in adults and children. Comprehensive protocols for clinical safety evaluations have demonstrated the highly favorable safety profile of UCA for intravenous, intravesical and other intracavitary uses. The safety data on CEUS continue to accumulate as this imaging modality is increasingly utilized in clinical settings worldwide. As of August 2021, 57 pediatric-only original research studies encompassing a total of 4,518 children with 4,906 intravenous CEUS examinations had been published. As in adults, there were a few adverse events; the majority of these were non-serious, although very rarely serious anaphylactic reactions were reported. In the published pediatric-only intravenous CEUS studies included in our analysis, the overall incidence rate of serious adverse events was 0.22% (10/4,518) of children and 0.20% (10/4,906) of all CEUS examinations. Non-serious adverse events from the intravenous CEUS were observed in 1.20% (54/4,518) of children and 1.10% (54/4,906) of CEUS examinations. During the same time period, 31 studies with the intravesical use of UCA were conducted in 12,362 children. A few non-serious adverse events were encountered (0.31%; 38/12,362), but these were most likely attributable to the bladder catheterization rather than the UCA. Other developing clinical applications of UCA in children, including intracavitary and intralymphatic, are ongoing. To date, no serious adverse events have been reported with these applications. This article reviews the existing pediatric CEUS literature and provides an overview of safety-related information reported from UCA uses in children.

Contrast-enhanced ultrasound of blunt abdominal trauma in children

Trauma is the leading cause of morbidity and mortality in children, and rapid identification of organ injury is essential for successful treatment. Contrast-enhanced ultrasound (CEUS) is an appealing alternative to contrast-enhanced CT in the evaluation of children with blunt abdominal trauma, mainly with respect to the potential reduction of population-level exposure to ionizing radiation. This is particularly important in children, who are more vulnerable to the hazards of ionizing radiation than adults. CEUS is useful in hemodynamically stable children with isolated blunt low- to moderate-energy abdominal trauma to rule out solid organ injuries. It can also be used to further evaluate uncertain contrast-enhanced CT findings, as well as in the follow-up of conservatively managed traumatic injuries. CEUS can be used to detect abnormalities that are not apparent by conventional US, including infarcts, pseudoaneurysms and active bleeding. In this article we present the current experience from the use of CEUS for the evaluation of pediatric blunt abdominal trauma, emphasizing the examination technique and interpretation of major abnormalities associated with injuries in the liver, spleen, kidneys, adrenal glands, pancreas and testes. We also discuss the limitations of the technique and offer a review of the major literature on this topic in children, including an extrapolation of experience from adults.

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.

Dynamic contrast-enhanced ultrasound of the bowel wall with quantitative assessment of Crohn's disease activity in childhood

Background

Contrast-enhanced ultrasound (CEUS) has become an established non-invasive, patient-friendly imaging technique which improves the characterization of lesions. In addition, dynamic contrast-enhanced ultrasound (DCE-US) provides valuable information concerning perfusion of examined organs. This review addresses current applications of CEUS in children, focused on DCE-US of the bowel wall in patients with Crohn disease, which enables realtime assessment of the bowel wall vascularity with semi-quantitative and quantitative assessment of disease activity and response to medical treatment.

Conclusions

Crohn’s disease is a chronic inflammatory relapsing disease. Frequent imaging re-evaluation is necessary. Therefore, imaging should be as little invasive as possible, children friendly with high diagnostic accuracy. US with wide varieties of techniques, including CEUS/DCE-US, can provide an important contribution for diagnosing and monitoring a disease activity. Even if the use of US contrast agent is off-label in children, it is welcome and widely accepted for intravesical use, and a little less for intravenous use, manly in evaluation of parenchymal lesions. To our knowledge this is the first time that the use of DCE-US in the evaluation of activity of small bowel Crohn disease with quantitative assessment of kinetic parameters is being described in children. Even if the results of the value and accuracy of different quantitative kinetic parameters in published studies in adult population often contradict one another there is a great potential of DCE-US to become a part of the entire sonographic evaluation not only in adults, but also in children. Further control studies should be performed.

Enhancing the role of paediatric ultrasound with microbubbles: a review of intravenous applications

Contrast-enhanced ultrasound (CEUS) represents a complementary technique to greyscale and colour Doppler ultrasonography which allows for real-time visualization and characterization of tissue perfusion. Its inherent advantages in the child makes ultrasonography an ideal imaging modality; repeatability and good tolerance along with the avoidance of CT, a source of ionizing radiation, renders ultrasonography imaging desirable. Although currently paediatric CEUS is principally used in an "off-label" manner, ultrasonography contrast agents have received regulatory approval for assessment of paediatric focal liver lesions (FLL) in the USA. The safety of ultrasound contrast-agents is well documented in adults, as safe as or even surpassing the safety profile of CT and MR contrast agents. Except for the established intracavitary use of CEUS in voiding urosonography, i.v. paediatric applications have been introduced with promising results in the abdominal trauma initial diagnosis and follow-up, characterization and differential diagnosis of FLL and characterization of lung, pleura, renal and splenic pathology. CEUS has also been used to detect complications after paediatric transplantation, evaluate inflammatory bowel disease activity and assess tumour response to antiangiogenic therapy. The purpose of this review was to present these novel i.v. paediatric applications of CEUS and discuss their value.

Off-Label Use of Ultrasound Contrast Agents for Intravenous Applications in Children: Analysis of the Existing Literature

OBJECTIVES

The purpose of this study was to collect and analyze the published data related to intravenous (IV) use of ultrasound (US) contrast agents in children.

METHODS

We searched the literature to collect all of the published studies reporting the IV administration of a second-generation US contrast agent in children.

RESULTS

We analyzed 9 case series and 5 case reports, as well as 5 individual cases, of pediatric contrast-enhanced US use reported in a study group that also included adults. We found that 502 children underwent contrast-enhanced US examinations (mean age, 9.7 years; range, 1 day-18 years). Most patients (89%) were injected with the sulfur hexafluoride contrast agent SonoVue (Bracco SpA, Milan, Italy). The mean dose used was 1.5 mL (range, 0.1-9.6 mL). Only 10 patients (2%) had adverse reactions related to the contrast agent administration: 1 life-threatening anaphylactic shock and 9 mild transitory adverse effects. We additionally found 38 papers in which the study groups included at least 1 child; thus, we obtained a total of 540 reported cases of off-label use of IV US contrast agents in children. The most frequent target organ was the liver, and most indications were related to space-occupying lesion characterization and abdominal evaluations after blunt trauma. Some studies also evaluated the diagnostic performance of contrast-enhanced US in different clinical scenarios and found very good accuracy. Concordance between contrast-enhanced US imaging and the respective reference-standard imaging methods ranged between 83% and 100% in different studies.

CONCLUSIONS

Our results support the idea that the IV use of US contrast agents in children is safe, feasible, diagnostically robust, and effective.

Contrast-enhanced ultrasound (CEUS) in blunt abdominal trauma

Baseline ultrasound is essential in the early assessment of patients with a huge haemoperitoneum undergoing an immediate abdominal surgery; nevertheless, even with a highly experienced operator, it is not sufficient to exclude parenchymal injuries. More recently, a new ultrasound technique using second generation contrast agents, named contrast-enhanced ultrasound (CEUS) has been developed. This technique allows all the vascular phase to be performed in real time, increasing ultrasound capability to detect parenchymal injuries, enhancing some qualitative findings, such as lesion extension, margins and its relationship with capsule and vessels. CEUS has been demonstrated to be almost as sensitive as contrast-enhanced CT in the detection of traumatic injuries in patients with low-energy isolated abdominal trauma, with levels of sensitivity and specificity up to 95%. Several studies demonstrated its ability to detect lesions occurring in the liver, spleen, pancreas and kidneys and also to recognize active bleeding as hyperechoic bands appearing as round or oval spots of variable size. Its role seems to be really relevant in paediatric patients, thus avoiding a routine exposure to ionizing radiation. Nevertheless, CEUS is strongly operator dependent, and it has some limitations, such as the cost of contrast media, lack of panoramicity, the difficulty to explore some deep regions and the poor ability to detect injuries to the urinary tract. On the other hand, it is timesaving, and it has several advantages, such as its portability, the safety of contrast agent, the lack to ionizing radiation exposure and therefore its repeatability, which allows follow-up of those traumas managed conservatively, especially in cases of fertile females and paediatric patients.

[Abdominal polytrauma and parenchymal organs]

CLINICAL/METHODOLOGICAL ISSUE

The acute radiological diagnostics of polytrauma patients has become an essential part of the interdisciplinary treatment in the emergency room. The incidence of polytrauma patients with an injury severity score (ISS) >16 is approximately 450 cases/million inhabitants/year in Europe. Injuries of the parenchymal organs are of utmost importance for the prognosis and treatment of these patients. The injury patterns are complex and a great deal of experience is necessary to be able to obtain the correct diagnosis within minutes. This review article deals with the radiological diagnostics and grading of the severity of injuries to the spleen, liver, pancreas and kidneys.

STANDARD RADIOLOGICAL METHODS

The use of ultrasound for the evaluation of polytraumatized patients will be discussed. The most important trauma-associated findings for the above mentioned organs using multidetector computed tomography (MDCT) will be described and illustrated by dedicated case findings.

METHODOLOGICAL INNOVATIONS

Ultrasound contrast agents can supply valuable, additional diagnostic information in the evaluation of polytraumatized patients. Computed tomography has become established as the most relevant imaging modality in severe trauma. Innovative organ-adapted and contrast application protocols improve the diagnostic performance of MDCT.

PRACTICAL RECOMMENDATIONS

The use of focused assessment sonography for trauma (FAST) scanning as a screening tool is in agreement with the other clinical disciplines of the trauma team. The use of MDCT is trauma-dependent and the classification of the severity of the different parenchymal organ injuries is ultimately decisive for further treatment and prognosis of trauma victims.

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.

Safety of ultrasound contrast agents in the pediatric oncologic population: a single-institution experience

OBJECTIVE

Little information is available regarding the safety of ultrasound contrast agents in children. The purpose of this article was to assess the safety profile of the i.v. administration of ultrasound contrast agents in the pediatric oncology population.

MATERIALS AND METHODS

Patients with pediatric solid malignancies who were enrolled on institutional clinical trials conducted between June 2003 and January 2013 and who met our institutional screening criteria for contrast-enhanced ultrasound (CEUS) were eligible. After providing informed consent or assent for CEUS, subjects received i.v. bolus injections of one of two contrast agents for imaging of the primary tumor or a metastatic target lesion. Hemodynamic parameters, including heart rate, cardiac rhythm, and oxygen saturation, were monitored immediately before and for 30 minutes after the administration of the contrast agent. Interviews with the subject or a guardian were conducted by the principal investigator or a radiologist coinvestigator before and after the examination to assess for any adverse effects.

RESULTS

Thirty-four subjects (21 male and 13 female) ranging in age from 8 months to 20.7 years (median, 8.7 years) underwent 134 CEUS. No detrimental change in hemodynamic status occurred in any subject. Three subjects (3/134, 2.2%) reported mild transient side effects on one occasion each, two (2/134, 1.5%) had taste alteration, and one (1/134, 0.8%) reported mild transient tinnitus and lightheadedness. These reactions did not recur in these subjects on subsequent CEUS examinations.

CONCLUSION

The i.v. administration of ultrasound contrast agents is safe and well tolerated in the pediatric oncology population. Further studies in children are needed to confirm our findings.

[Ultrasound examination in childhood: new perspectives]

Everyday use of the modern imaging techniques such as CT, MRI, isotope, PET/CT decreased the reputation and importance of ultrasound. In some cases, ultrasound is only the first exploratory imaging method. Using the latest multi-slice CT, imaging can be performed in seconds, which led to a dramatic increase in the number of CT exams. However, this also means a significant radiation exposure to children, while US still harmless in this regard. In addition, significant progress has been made in ultrasound technology in recent years, which led an improvement in image quality. Children are ideal subjects for US examination as they usually have smaller weight with less body fat. Thus, ultrasound examination is easy to perform with a high frequency transducer resulting in much more detailed and higher resolution than in adults. With adequate equipment and experienced examiner in pediatric radiology, almost all parts of the body can be examined, making this technique as the first (sometimes together with X-ray) and, in most cases, the ultimate imaging exam for the diagnosis. This article will discuss the possibilities where ultrasound performed with a modern device is sufficient for an accurate diagnosis.

Safety of contrast-enhanced ultrasound in children for non-cardiac applications: a review by the Society for Pediatric Radiology (SPR) and the International Contrast Ultrasound Society (ICUS)

The practice of contrast-enhanced ultrasound in children is in the setting of off-label use or research. The widespread practice of pediatric contrast-enhanced US is primarily in Europe. There is ongoing effort by the Society for Pediatric Radiology (SPR) and International Contrast Ultrasound Society (ICUS) to push for pediatric contrast-enhanced US in the United States. With this in mind, the main objective of this review is to describe the status of US contrast agent safety in non-cardiac applications in children. The five published studies using pediatric intravenous contrast-enhanced US comprise 110 children. There is no mention of adverse events in these studies. From a European survey 948 children can be added. In that survey six minor adverse events were reported in five children. The intravesical administration of US contrast agents for diagnosis of vesicoureteric reflux entails the use of a bladder catheter. Fifteen studies encompassing 2,951 children have evaluated the safety of intravesical US contrast agents in children. A European survey adds 4,131 children to this group. No adverse events could be attributed to the contrast agent. They were most likely related to the bladder catheterization. The existing data on US contrast agent safety in children are encouraging in promoting the widespread use of contrast-enhanced US.

Application of a second-generation US contrast agent in infants and children--a European questionnaire-based survey

BACKGROUND

No US contrast agent (US-CA) is currently licensed for use in children.

OBJECTIVE

To survey the off-label use in children of a second-generation US-CA.

MATERIALS AND METHODS

Questionnaires were e-mailed to European paediatric radiologists, who were asked about their experience with the second-generation US-CA Sonovue® (Bracco, Milan, Italy). Number of examinations per indication and adverse effects were recorded. Examinations were categorised by intravenous or intracavitary use of US-CA.

RESULTS

Out of 146 respondents, 88 stated that they did not perform contrast-enhanced US in children, but 36 of these (44%) would appreciate paediatric approval. Forty-five centres reported 5,079 examinations in children (age mean: 2.9 years; range: birth-18 years, M/F: 1/ 2.8). The majority (4,131 [81%] in 29 centres) were intravesical applications. The minority (948 [19%] in 30 centres) were intravenous applications. No adverse effects had been recorded from intravesical use. Six minor adverse effects (skin reaction, unusual taste, hyperventilation) had been recorded after five intravenous studies (0.52%).

CONCLUSION

Responses suggest a favourable safety profile of this second-generation US-CA in children. It also demonstrates a demand for such US-CA from paediatric radiologists.

Computed tomography for pancreatic injuries in pediatric blunt abdominal trauma

AIM: To evaluate the efficacy of computed tomography scan in diagnosing and grading the pattern of pancreatic injuries in children.

METHODS: We conducted a retrospective study to review medical files of children admitted with blunt pancreatic injuries to the Maternity and Children Hospital Al-Madina Al-Munawwarah, Kingdom of Saudi Arabia. The demographic details and mechanisms of injury were recorded. From the database of the Picture Archiving and Communication System of the radiology department, multidetector computed tomography (MDCT) images of the pancreatic injuries, severity, type of injuries and grading of pancreatic injuries were established.

RESULTS: Seven patients were recruited in this study over a period of 5 years; 5 males and 2 females with a mean age of 7 years (age range 5-12 years). Fall from height was the most frequent mechanism of injury, reported in 5 (71%), followed by road traffic accident (1 patient, 14%) and cycle handlebar (1 patient, 14%) injuries. According to the American Association for the Surgery of Trauma grading system, 1 (14%) patient sustained Grade I, 1 (14%) Grade II, 3 (42%) Grade III and 2 (28%) patients were found to have Grade V pancreatic injuries. This indicated a higher incidence of severe pancreatic injuries; 5 (71.4%) patients were reported to have Grade III and higher on the injury scale. Three (42%) patients had associated abdominal organ injuries.

CONCLUSION: Pediatric pancreatic injuries due to blunt abdominal trauma are rare. The majority of the patients sustained extensive pancreatic injuries. MDCT findings are helpful and reliable in diagnosing and grading the pancreatic injuries.

Contrast-enhanced sonography of malignant pediatric abdominal and pelvic solid tumors: preliminary safety and feasibility data

BACKGROUND

Little information exists regarding pediatric contrast-enhanced US.

OBJECTIVE

To assess the safety and feasibility of contrast-enhanced US of pediatric abdominal and pelvic tumors.

MATERIALS AND METHODS

This prospective study included eight boys and five girls (mean age, 10.8 years) with abdominal or pelvic tumors. Cohorts of three subjects underwent US with perflutren contrast agent at escalating dose levels. Neurological and funduscopic examination, electrocardiography and continuous pulse oximetry were performed before and after contrast administration. Three radiologists independently scored six imaging parameters on pre- and postcontrast sonography. Inter-reviewer agreement was measured by the Kappa statistic.

RESULTS

No neurological, retinal, electrocardiographical or pulse oximetry changes were attributable to the contrast agent. Two subjects reported minor, transient symptoms. Postcontrast US parameter scores improved slightly in 8 of 12 subjects. Postcontrast ultrasound inter-reviewer agreement improved slightly for detection of tumor margins (precontrast = 0.20, postcontrast = 0.26), local tumor invasion (precontrast = -0.01, postcontrast = 0.10) and adenopathy (precontrast = 0.35, postcontrast = 0.44).

CONCLUSIONS

Although our sample size is small, perflutren contrast agents appear to be safe and well tolerated in children. Contrast-enhanced sonography of pediatric abdominal and pelvic tumors is feasible, but larger studies are needed to define their safety and efficacy in children.

Ultrasound contrast media in paediatric patients: is it an off-label use? Regulatory requirements and radiologist's liability

The use of ultrasound contrast media is yet to be validated in children. The rare reports in the scientific literature denote their "sporadic" and "experimental" use. Their most likely use is in the setting of off-label prescription of medications. As there are still no guidelines available in Italy for the off-label use of medications, we aim to define the duties, obligations and liability of ultrasound radiologists according to the laws in force.

Role of contrast enhanced ultrasound in acute scrotal diseases

OBJECTIVE

To evaluate the efficacy of contrast-enhanced ultrasound (CEUS) in patients with acute scrotal pain not defined at ultrasound (US) with colour Doppler .

METHODS

CEUS was carried out in 50 patients with acute scrotal pain or scrotal trauma showing testicular lesion of undefined nature at US. The accuracy of US and CEUS findings versus definitive diagnosis (surgery or follow-up) was calculated.

RESULTS

Twenty-three patients had a final diagnosis of testicular tumour, three abscess, eight focal infarction, seven trauma, three testicular torsion, one haematoma. Five patients were negative. Thirty-five patients were operated (23 testicular tumours, six trauma, three testicular torsion, one abscess, one focal infarction, and one haematoma) and 15 underwent medical treatment or were discharged. US provided a definitive diagnosis in 34/50 as compared to the 48/50 patients diagnosed at CEUS. Sensitivity and specificity were 76% and 45% for US and 96% and 100% for CEUS respectively.

CONCLUSIONS

CEUS was more accurate in the final diagnosis compared to US, potentially reducing the need for further imaging. In particular CEUS can be proposed in emergency in cases where US diagnosis remains inconclusive, namely in infarction, and trauma, when testicular torsion cannot be ruled out, and in identifying testicular mass.

Detection of urinary leakage after radical retropubic prostatectomy by contrast enhanced ultrasound - do we still need conventional retrograde cystography?

INTRODUCTION

To prospectively evaluate the accuracy of transvesical contrast-enhanced ultrasound (CEUS) as an alternative method for the detection of anastomotic leakage after radical retropubic prostatectomy (RRP) in comparison with the current standard method of conventional retrograde cystography (CG).

PATIENTS AND METHODS

Forty-three patients underwent RRP for histologically proven localized prostate cancer. The vesico-urethral anastomosis was evaluated 8 days after RRP by CG and CEUS. Any peri-anastomotic leakage was assessed and determined in CG and CEUS as follows: no extravasation (EV), small leakage (≤0.5 cm), moderate leakage (>0.5 cm to ≤2 cm), large leakage (>2 cm diameter of EV seen).

RESULTS

In total, 21 (49%) patients showed a watertight anastomosis. Ten (23%), two (4.7%) and ten (23%) patients showed a small, intermediate and large EV, respectively. In 31 cases (72%) there was 100% agreement of CG and CEUS for detection of no, moderate and large EV, respectively. In nine cases a small and in two cases a moderate EV was categorized as watertight anastomosis by CEUS. Only in one case did CG detect a small EV where a large EV was detected in CEUS. The agreement between both methods was 95% for detecting absence or large leakages.

CONCLUSION

CEUS is a promising imaging modality that seems to be equivalent to CG for detecting the presence of a large anastomotic leakage that is clinically relevant for postoperative persistence of the indwelling catheter. CEUS could be a cheap and time-saving alternative to the CG without exposure of the patient to radiation.

CEUS in abdominal trauma: multi-center study

The objective of this study was to evaluate the concordance of US and contrast-enhanced US (CEUS) with CT in the assessment of solid organ injury following blunt trauma. Patients underwent complete US examination, including free fluid search and solid organ analysis. CEUS followed, using low-mechanical index techniques and SonoVue. CT was performed within 1 h. Among 156 enrolled patients, 91 had one or more abnormalities (n = 107) at CT: 26 renal, 38 liver, 43 spleen. Sensitivity, specificity, and accuracy for renal trauma at baseline US were 36%, 98%, and 88%, respectively, after CEUS values increased to 69%, 99%, and 94%. For liver baseline US values were 68%, 97%, and 90%; after CEUS were 84%, 99%, and 96%. For spleen, results were 77%, 96%, and 91% at baseline US and 93%, 99%, and 97% after CEUS. Per patient evaluation gave the following results in terms of sensitivity, specificity and accuracy: 79%, 82%, 80% at baseline US; 94%, 89%, and 92% following CEUS. CEUS is more sensitive than US in the detection of solid organ injury, potentially reducing the need for further imaging. False negatives from CEUS are due to minor injuries, without relevant consequences for patient management and prognosis.

[The value of sonography in traumatology and orthopedics : Part 2: emergency diagnostics in blunt abdominal and thoracic trauma]

Ultrasound examinations in trauma patients should be done in the emergency department using curved-array (3.5-7.5 MHz) probes. Blunt trauma of the abdomen and thorax must be regarded as a single organ injury. Sonography is the imaging technique of first choice and has completely replaced peritoneal lavage. Paramount advantages are its ability to provide rapid information and reproducible results at short intervals and in a noninvasive manner. The sensitivity and specificity of sonography in detecting intraabdominal fluid are 97-100% and 80-90%, respectively. To achieve such good results, though, adequate education in ultrasound and state-of-the-art devices is crucial. Clinical experiences prove that standardized sonography must be part of polytrauma management and should be integrated in advanced trauma life support courses. Technical improvements with better image quality and miniaturization of hardware will contribute to increase the use of this technique. However, ultrasound does not replace computed tomography for follow-up in answering more sophisticated questions in multiple injured patients.

Diagnosis of Hepatosplenic Sarcoidosis by Contrast-Enhanced Ultrasound Guided Needle Biopsy

Sarcoidosis is a systemic disease characterised by non-caseating multiple granulomas involving virtually any organ in the body. The aetiology and natural history of sarcoidosis remains obscure. Hepatosplenic sarcoidosis is rare with image-based diagnosis difficult if no other organ is already involved. This case report describes a patient with asymptomatic liver and spleen involvement in which a final diagnosis was achieved with contrast enhanced ultrasound (CEUS) guided liver biopsy.

Emergency real-time contrast-enhanced ultrasonography for detection of solid organ injuries

BACKGROUND

There is no controversy about the use of CT for detection of internal injuries in patients with high-energy multitrauma. However, in most patients isolated blunt abdominal trauma is mild or moderate and the risk of injury to organs other than the liver, spleen or kidneys is minimal. CT scanning exposes patients to radiation, and may often be avoided if significant damage to these three organs can be visualized by contrast-enhanced ultrasonography (CEUS).

MATERIALS AND METHODS

In our series SonoVue (Bracco, Milan) and Siemens Acuson Sequoia ultrasound machines were used. Initially patients with injuries detected by CT were examined using CEUS. Subsequently CEUS was used as the first and only modality in patients with mild or moderate blunt abdominal trauma to one flank, provided that they were able to cooperate and were otherwise suitable for US examination.

RESULTS

CEUS was able to sensitively detect lacerations and haematomas in the liver, spleen and kidneys in cooperative patients. CEUS also demonstrated very thin lacerations of the parenchyma of these organs. These results were also found in children.

CONCLUSION

In our experience CEUS is an accurate and valuable tool for the detection or exclusion of parenchymal damage to the liver, spleen and kidneys. With the proper organization, standardized dynamic documentation and well-trained sonographers, CEUS may replace CT in many patients with mild to moderate blunt abdominal trauma, thus avoiding unnecessary exposure to radiation in this often young and healthy population.

Blunt abdominal trauma: diagnostic performance of contrast-enhanced US in children--initial experience

PURPOSE

To prospectively compare the sensitivity and specificity of ultrasonography (US) with those of contrast material-enhanced US in the depiction of solid organ injuries in children with blunt abdominal trauma, with contrast-enhanced computed tomography (CT) as the reference standard.

MATERIALS AND METHODS

The study protocol was approved by the ethics board, and written informed consent was obtained from parents. US, contrast-enhanced US, and contrast-enhanced CT were performed in 27 consecutive children (19 boys, eight girls; mean age, 8.9 years +/- 2.8 [standard deviation]) with blunt abdominal trauma to determine if solid abdominal organ injuries were present. Sensitivity, specificity, agreement, accuracy, number of lesions correctly identified, and positive and negative predictive values were determined for US and contrast-enhanced US, as compared with contrast-enhanced CT.

RESULTS

In 15 patients, contrast-enhanced CT findings were negative. Contrast-enhanced CT depicted 14 solid organ injuries in 12 patients. Lesions were in the spleen (n = 7), liver (n = 4), right kidney (n = 1), right adrenal gland (n = 1), and pancreas (n = 1). Contrast-enhanced US depicted 13 of the 14 lesions in 12 patients with positive contrast-enhanced CT findings and no lesions in the patients with negative contrast-enhanced CT findings. Unenhanced US depicted free fluid in two of 15 patients with negative contrast-enhanced CT findings and free fluid, parenchymal lesions, or both in eight of 12 patients with positive contrast-enhanced CT findings. Overall, the diagnostic performance of contrast-enhanced US was better than that of US, as sensitivity, specificity, and positive and negative predictive values were 92.2%, 100%, 100%, and 93.8%, respectively.

CONCLUSION

Contrast-enhanced US was almost as accurate as contrast-enhanced CT in depicting solid organ injuries in children.

Microbubble ultrasound contrast agents: an update

Microbubble contrast agents for ultrasound (US) have gained increasing interest in recent years, and contrast-enhanced US (CEUS) is a rapidly evolving field with applications now extending far beyond the initial improvements achieved in Doppler US. This has been achieved as a result of the safe profile and the increased stability of microbubbles persisting in the bloodstream for several minutes, and also by the availability of specialized contrast-specific US techniques, which allow a definite improvement in the contrast resolution and suppression of signal from stationary tissues. CEUS with low transmit power allows real-time scanning with the possibility of prolonged organ insonation. Several reports have described the effectiveness of microbubble contrast agents in many clinical applications and particularly in the liver, spleen, and kidneys. CEUS allows the assessment of the macrovasculature and microvasculature in different parenchymas, the identification and characterization of hepatic and splenic lesions, the depiction of septal enhancement in cystic renal masses, and the quantification of organ perfusion by the quantitative analysis of the echo-signal intensity. Other fields of application include the assessment of abdominal organs after traumas and the assessment of vesico-ureteral reflux in children. Finally, tumor-targeted microbubbles make possible the depiction of specific biologic processes.

Contrast-enhanced sonography of the spleen

Sonography is frequently the first imaging modality employed to evaluate the spleen. Nevertheless, splenic abnormalities frequently determine subtle changes in echogenicity and may be overlooked. Additionally, splenic disorders have a nonspecific appearance, mostly appearing as hypoechoic defects. Difficulties in differential diagnosis are not uncommon, with splenic infarctions resembling, for example, focal lesions. Color Doppler is usually of limited additional value. Instead, the spleen is optimally suited for contrast-enhanced sonography, being superficial, small, and homogeneous, and showing intense and persistent contrast enhancement. Scarcely evident abnormalities become evident after contrast medium injection. Additional information can be obtained in many clinical scenarios, including blunt trauma, left flank pain, lymphoma, and incidental detection of splenic abnormalities.

Active abdominal bleeding: contrast-enhanced sonography

Active contrast medium extravasation is a recognized and important angiographic and computed tomographic (CT) sign of bleeding. It is an indicator of active, ongoing, and potentially life-threatening hemorrhage and, hence, of the need for an immediate surgical or interventional treatment. Sonography (US) is frequently used as the first imaging option for screening patients with traumatic and nontraumatic abdominal emergencies. Owing to the current possibilities of low-mechanical index, real-time, contrast-specific systems, it is now possible to detect a contrast leakage by using US. This finding opens new possibilities in the assessment and management of several abdominal emergencies, including trauma (initial workup and monitoring), spontaneous hematomas, and rupture of aneurysms or masses. This article describes the technique, findings, possibilities, and limitations of contrast-enhanced US in the evaluation of active abdominal bleeding.

Contrast-enhanced ultrasound in non-operative management of pancreatic injury in childhood

We report a 5-year-old child with pancreatic trauma from a blunt abdominal injury that was monitored with contrast-enhanced sonography. Unenhanced US failed to demonstrate the abnormality that was recognized by CT and MRI. The injury was well demonstrated by contrast-enhanced US which was therefore used for follow-up until its healing.

Real-time, contrast-enhanced sonography: a new tool for detecting active bleeding

BACKGROUND

Active contrast medium extravasation is a known angiographic and computed tomographic sign of ongoing, potentially life-threatening hemorrhage. Sonography (US) is frequently the first imaging option for screening patients with abdominal emergencies. Because of the current possibilities of low-mechanical-index, real-time, contrast-specific systems, it is possible to detect contrast leakage by using US. The purpose of this article is report our pilot experience in the evaluation of active traumatic and nontraumatic bleeding with contrast-enhanced US.

METHODS

In a 2-year period, we performed 153 consecutive emergent contrast-enhanced US studies. Traumatic emergencies accounted for 83 examinations and nontraumatic emergencies accounted for 70. We used the contrast-specific mode Contrast Tuned Imaging and the contrast medium SonoVue. A 2.4- to 4.8-mL contrast medium bolus was injected with continuous US acquisition, starting immediately after contrast injection and lasting 1 to 6 minutes.

RESULTS

Contrast extravasation was found in 20 cases (13%). These included spleen injury (n = 8), liver injury (n = 3), kidney injury (n = 1), abdominal aortic aneurysm rupture (n = 5), splenic angiosarcoma rupture (n = 1), postsurgical bleeding after abdominal aortic aneurysm repair (n = 1), and postsplenectomy bleeding (n = 1). Active extravasation appeared as a round, hyperechoic pool or as a fountain-like, hyperechoic jet.

CONCLUSION

Our retrospective clinical study shows for the first time how US can detect contrast medium extravasation, a significant indicator of active hemorrhage and of need for prompt surgical or interventional treatment.

Ultraschallkontrastmittel: Substanzklassen, Pharmakokinetik, klinische Anwendungen, Sicherheitsaspekte

Ultrasound contrast agents (UCA) have undergone constant development and improvement in recent years. Greater mechanical stability and improved acoustic properties, combined with new contrast-specific ultrasound sequences, have broadened the potential fields for investigation considerably. Contrast-enhanced ultrasound studies will no longer be complementary investigations, but will be considered as primary techniques. This review article provides a survey of the different drugs used, their chemical properties, and their pharmacokinetic aspects. Summarized are the most important established and published indications for the use of UCA together with an outlook for future applications. Finally this paper discusses the safety profile of these agents, which has become important due to the increasing use of these agents.

Contrast-enhanced sonography of the spleen

OBJECTIVE

Combined use of low-mechanical-index technologies and non-air-filled contrast media allows real-time sonographic assessment of the spleen. This pictorial essay focuses on several aspects of contrast-enhanced sonography of the spleen, including examination technique, clinical indications, normal findings obtained through all vascular phases, abnormal findings (splenomegaly, infarction, abscess, benign tumors, lymphoma, metastasis, injuries, and accessory spleen), limitations, and pitfalls.

CONCLUSION

Real-time, contrast-enhanced sonography is a novel technique allowing depiction of a wide range of splenic abnormalities.

Blunt hepatic trauma: evaluation with contrast-enhanced sonography: sonographic findings and clinical application

OBJECTIVE

The purpose of this study was to report our initial experience in the assessment of liver trauma with real-time contrast-enhanced sonography (CES).

METHODS

From January 2000 to December 2003, there were 431 hemodynamically stable patients evaluated with sonography for blunt abdominal trauma. Among these patients, 87 were selected to undergo second-level imaging, consisting of CES and computed tomographic (CT) evaluation. Indications for further assessment were baseline sonographic findings positive for liver injury, baseline sonographic findings positive for injury to other abdominal parenchyma, baseline sonographic findings positive for free fluid only, baseline sonographic findings indeterminate, and baseline sonographic findings negative with persistent clinical or laboratory suspicion.

RESULTS

There were 23 hepatic lesions shown by CT in 21 patients. Peritoneal or retroperitoneal fluid was identified in 19 of 21 positive cases by all 3 imaging modalities. Liver injury was found in 15 patients on sonography and in 19 on CES. Contrast-enhanced sonography compared better than unenhanced sonography with the criterion standard for related injury conspicuity, injury size, completeness of injury extension, and involvement of the liver capsule. Both CES and CT showed intrahepatic contrast material pooling in 2 cases. All patients with false-negative sonographic or CES findings recovered uneventfully.

CONCLUSIONS

Contrast-enhanced sonography is an effective tool in the evaluation of blunt hepatic trauma, being more sensitive than baseline sonography and correlating better than baseline sonography with CT findings. In institutions where sonography is regarded as the initial procedure to screen patients with trauma, this technique may increase its effectiveness. In addition, CES may be valuable in the follow-up of patients with conservatively treated liver trauma.