Real-time, contrast-enhanced sonographic imaging in emergency radiology

PURPOSE: To report our pilot experience in the evaluation of traumatic and nontraumatic emergencies with contrast-specific, continuous-mode sonography (US) and a second-generation contrast medium. MATERIALS AND METHODS: Between January 2002 and December 2003 we evaluated 126 acute patients by using real-time contrast-specific US: blunt abdominal trauma (76 cases), penetrating abdominal trauma (3), blunt scrotal trauma (1), right upper abdominal pain (10), left upper abdominal pain (9), epigastric pain (2), flank pain (5), right lower abdominal pain (2), scrotal pain (7), postoperative abdominal sepsis (1), post-biopsy haemorrhage (1), ruptured abdominal aortic aneurysm (8), postsurgical aortic bleeding (1). In all cases the radiologist performed a complete baseline US survey and then decided whether or not to add a contrast-enhanced examination. RESULTS: All contrast-enhanced sonographic studies were completed proving to be adequate for diagnostic purposes and without adverse reactions to contrast medium. There were 40 true negatives. The final diagnosis, obtained in 85 positive cases out of 86, was: splenic injury (28 cases), hepatic injury (3), renal injury (3), multiple injuries (3), pancreatic and portal vein injury (1), colonic-mesocolic injury (1), testicular trauma (1), hepatic abscess (9), hepatic ischaemia (1), gangrenous cholecystitis (1), splenic infarction (8), splenic haematoma abscess (1), renal infection (4), renal infarction (1), necrotizing pancreatitis (1), post-biopsy haemorrhage (1), appendicitis (2), peritoneal abscesses (1), testicular torsion (6), orchiepididymitis (1), iliac artery dissection (1), ruptured abdominal aortic aneurysm (6), aortic periprosthetic hemorrhage (1). Out of 85 positive cases, agreement between baseline US and contrast-specific US was absent in 8% of cases, low in 26%, intermediate in 42%, and high in 24%. Baseline US had 3 false positives. Relevance of contrast-specific US was absent in 17% of cases, low (additional data not relevant for patient management) in 26%, intermediate (relevant additional data not modifying patient management) in 34%, and high (additional data modifying patient management) in 23%. Agreement between contrast-specific US and the gold standards was absent in 0% of cases, low in 6%, intermediate in 38%, and high in 56%. Contrast-specific US had 2 false positive results. CONCLUSIONS: Real-time contrast-specific US is an effective technique in emergency imaging. Its role should not be considered as a replacement of CT (though in some instances it can be considered a valuable alternative) but as a useful integration of conventional US. By always having the opportunity to add contrast-enhanced imaging, in case of interpretation doubts or diagnostic difficulties, the radiologist can assess the emergency patient with improved confidence and skill.     

Real-time contrast-enhanced ultrasound of the spleen: examination technique and preliminary clinical experience

PURPOSE: To report our preliminary experience in the evaluation of the spleen using a real-time contrast-specific ultrasound module in combination with a second-generation contrast agent. MATERIALS AND METHODS: In a 7-month period, 55 patients (34 males and 21 females, aged 5-77 years) with spleen disorders were evaluated by means of contrast-enhanced ultrasound. Two patients were studied because of baseline evidence of an accessory spleen and both underwent ultrasound follow-up. Twenty-five patients were studied for abdominal trauma and results were correlated with those of helical CT. Three patients were examined for suspected splenic infarction and for all CT correlation was obtained. Finally, twenty-five subjects were examined for focal diseases, such as lymphomas (17 cases) and focal lesions (8 cases); contrast-enhanced US results were correlated with those of CT (8 cases), MRI (2 cases), ultrasound follow-up (8 cases), biopsy (2 cases) or splenectomy (1 case). After an initial baseline study, the contrast-enhanced examinations were carried out using a dedicated unit equipped with a continuous contrast-specific module at low acoustic pressure. The examination started immediately after rapid contrast injection and lasted approximately 4 minutes. In the comparison between baseline and contrast-enhanced ultrasound, the following aspects were considered: detection rate of parenchymal changes, lesion extent (equal to CT, under- or overestimated), and lesion conspicuity (lesion-to-parenchyma gradient, from 0 = absent to 3 = high). RESULTS: In the 2 patients with accessory spleen, an enhancement very similar to that of the adjacent parenchyma was present and a small vascular pedicle was noted. Among the trauma patients, 18 had a direct splenic injury and one showed splenic contraction and hypoperfusion due to shock. In 74% of cases, a peritoneal effusion was demonstrated both with baseline and contrast-enhanced ultrasound; perisplenic blood collections (58% of cases) were identified in 42% of patients by both baseline and contrast-enhanced ultrasound; post-traumatic infarction was always revealed by contrast-enhanced ultrasound (11% of cases) but never by baseline ultrasound; parenchymal injuries were detected with a sensitivity of 63% by baseline ultrasound and a sensitivity of 89% by contrast-enhanced ultrasound. Moreover, contrast-enhanced ultrasound revealed findings undetectable on conventional ultrasound: global splenic hypoperfusion in 2 cases (due to shock in one and pedicle avulsion in the other), intraparenchymal contrast collections in 21% of positive cases (as confirmed by CT), extrasplenic contrast leakage in 1 of 2 cases demonstrated by CT. Of the 3 cases of splenic infarction, baseline sonography only only identified two, whereas the contrast-enhanced examination clearly identified three. Contrast-enhanced ultrasound revealed 35 of 39 focal lesions in patients studied for Hodgkin's disease and splenic focal lesions. Baseline ultrasound had a lower sensitivity (23 lesions). Lesion extension shown by contrast-enhanced sonography was equivalent to that provided by standard methods in 88% of cases (underestimated in 9% and overestimated in 3%); baseline US correctly estimated lesion size in 52% of cases, under- and overestimating them in 35% and 13% of cases, respectively. Lesion conspicuity was graded as 1 (low) in 16%, 2 (moderate) in 67%, and 3 (high) in 17% of the cases identified by enhanced sonography. Baseline ultrasound was less effective: conspicuity was graded as 1 in 42%, 2 in 39%, and 3 in 19% of cases. CONCLUSIONS: The spleen is the ideal organ to be studied with second-generation contrast media due to its superficial location, high vascularity, small size and homogeneous texture. Contrast-enhanced ultrasound is a simple, poorly-invasive and accurate tool for the evaluation of splenic disorders. If our data are confirmed, it will be possible to reduce the use of more complex technologies such as CT and MRI.     

Doppler power with contrast media in the characterization of renal masses

PURPOSE: To report the results of a prospective study investigating the potentials of contrast-enhanced power Doppler in the diagnosis of expansive renal lesions. MATERIAL AND METHODS: From 1997 to October 30, 1999, we studied 59 expansive renal lesions (28 malignant, 31 benign) in 48 patients (mean age 55 years, range 10-79) with power Doppler US before and after the administration of an echo-enhancing agent (Levovist, Schering AG, Berlin, Germany). We identified 5 patterns of vascular architecture of the lesions, both before and after contrast agent administration, following the classification by Jinzaki e Coll. RESULTS AND DISCUSSION: Power Doppler US showed vascular structures in 34 patients. The administration of Levovist revealed vessels in 12/25 lesions which had none at baseline studies and in 6 cases vascularity was particularly evident. Color signals were enhanced in all the 34 vascularized lesions, which allowed better definition of vascular patterns. The characterization of vascular patterns with baseline power Doppler US helped improve diagnostic accuracy compared to gray-scale US (58% versus 32%) for hyperechoic lesions, complex cysts and pseudomasses. Independent of contrast agent administration, the integration of gray-scale and power Doppler modes increased diagnostic accuracy even further (76% correct diagnoses). CONCLUSIONS: In our series, the US contrast agent did not increase the diagnostic accuracy of power Doppler in the differential diagnosis of hyperechoic renal lesions; conversely, Levovist can be advantageous for the characterization of suspected pseudomasses and complex cysts.     

Comparison of diagnostic performance of unenhanced vs SonoVue - enhanced ultrasonography in focal liver lesions characterization. The experience of three Italian centers

PURPOSE: To evaluate the diagnostic performance of contrast-enhanced US with SonoVue (Bracco, Milan, Italy) compared to baseline US in focal hepatic lesions characterization. MATERIALS AND METHODS: A comprehensive number of four operators from 3 hospitals evaluated 57 consecutive patients with 60 focal hepatic lesions (28 hepatocellular carcinomas, 11 metastases, 13 hemangiomas, 1 hepatocellular adenoma and 7 focal nodular hyperplasias) by baseline gray-scale ultrasound (US) and color Doppler US. The same lesions were subsequently scanned by contrast-enhanced US after intravenous bolus administration of 2,4-4,8 ml of SonoVue by employing intermittent high or continuous low transmit power imaging. The diagnosis of lesions nature (benign or malignant) and histotype proposed by the on-site operator was finally compared to the definite diagnosis reached by reference procedures (multiphasic contrast-material enhanced helical-computed tomography or magnetic resonance in 24 lesions and fine needle US guided biopsy in 36 lesions). Diagnostic performance (sensitivity, specificity and overall accuracy expressed by the agreement with the reference procedures) of baseline and contrast enhanced US were compared. RESULTS: Differences in sensitivity (baseline vs contrast-enhanced US: 13/39 [33%] vs 32/39 [82%]), specificity (baseline vs contrast-enhanced US: 12/21 [57%] vs 16/21 [76%]) and overall accuracy (baseline vs contrast-enhanced US: 25/60 [41%] vs 47/60 [78%]) were significant (p<0.05; McNemar test). CONCLUSIONS: SonoVue-enhanced US determined a significant improvement in diagnostic performance in the characterization of focal liver lesions if compared to baseline US.     

US characterization of focal hepatic lesions with intermittent high-acoustic-power mode and contrast material

RATIONALE AND OBJECTIVES: This study was performed to determine whether ultrasound (US) performed with SonoVue, a contrast agent that contains microbubbles filled with sulfur hexafluoride vapor, depicts differential patterns of contrast enhancement in focal hepatic lesions. MATERIALS AND METHODS: Forty focal hepatic lesions (15 hepatocellular carcinomas [HCCs], 10 metastases, 11 hemangiomas, and four focal nodular hyperplasias) in 39 patients were evaluated by means of US, color Doppler US, and contrast-enhanced US performed by using intermittent high-acoustic-power mode. Contrast-enhanced helical computed tomography (11 patients) and US-guided fine needle aspiration (28 patients) were used as reference procedures. Contrast enhancement patterns were defined by means of both subjective and objective analysis, and baseline and contrast-enhanced US scans were reviewed offline. RESULTS: Thirteen of 15 HCCs, eight of 10 metastases, and all four hemangiomas with an atypical pattern at baseline US were correctly characterized after SonoVue injection. Two of 15 HCCs and two of 10 metastases remained indeterminate, with no characteristic baseline or contrast-enhanced patterns identified. Baseline US was essential in characterizing all hemangiomas with a typical pattern (n = 7), and color Doppler US with spectral analysis of tumoral vessels was essential in characterizing focal nodular hyperplasia. The percentage of diagnostic agreement with reference procedures was significantly increased (P < .001) for contrast-enhanced US compared with baseline US. CONCLUSION: Characteristic patterns of US contrast enhancement with SonoVue help in characterizing and differentiating focal hepatic lesions.     

Perirenal fluid in renal parenchymal medical disease ('floating kidney'): clinical significance and sonographic grading.

AIM: To study the clinical significance and radiologic features of perirenal fluid in patients with renal parenchymal disease. MATERIALS AND METHODS: During the previous 5 years, nine patients were found to have perirenal fluid on sonography associated with renal parenchymal medical disease. The clinical, radiological, histopathological and laboratory data were analysed. RESULTS: The perirenal fluid is a spontaneous subcapsular transudate in patients suffering from a nephropathy with a sodium retention state, with or without renal failure. Three sonographic patterns of perirenal fluid were observed: grade 1 is a thin layer of perirenal fluid; grade 2 is a moderate amount of perirenal fluid collection with indentations of the renal parenchyma and strands in the fluid, grade 3 is a large fluid collection surrounding the kidney. CONCLUSION: The perirenal fluid represents a sign of sodium retention state and oedema in patients with intrinsic renal parenchymal medical disease which may be caused by several nephropathies.     

Characterization of focal liver lesions with contrast-specific US modes and a sulfur hexafluoride-filled microbubble contrast agent: diagnostic performance and confidence

PURPOSE: To assess whether characterization of solid focal liver lesions could be improved by using ultrasonographic (US) contrast-specific modes after sulfur hexafluoride-filled microbubble contrast agent injection, as compared with lesion characterization achieved with preliminary baseline US. MATERIALS AND METHODS: Four hundred fifty-two solid focal hepatic lesions that were considered indeterminate at baseline gray-scale and color Doppler US were examined after microbubble contrast agent injection performed by using low-acoustic-power contrast-specific modes during the arterial (10-40 seconds after injection), portal venous (50-90 seconds after injection), and late (100-300 seconds after injection) phases. Two readers independently and retrospectively reviewed baseline and contrast material-enhanced US scans and classified each depicted lesion as malignant or benign according to standard diagnostic criteria. Sensitivity, specificity, accuracy, and positive and negative predictive values and areas under the receiver operating characteristic curve (Az) were calculated by considering histologic analysis (317 patients) or contrast-enhanced helical computed tomography followed by serial US 3-6 months apart (135 patients) as the reference standards. RESULTS: Different contrast enhancement patterns were observed according to lesion characteristics. During the late phase, benign lesions were predominantly hyper- or isoechoic relative to the adjacent liver parenchyma, whereas malignant lesions were predominantly hypoechoic. Review of the contrast-enhanced US scans after baseline image review yielded significantly improved diagnostic performance (P <.05). Overall diagnostic accuracy was 49% before versus 85% after review of the contrast-enhanced scan for reader 1 and 51% before versus 88% after review of the contrast-enhanced scan for reader 2. Diagnostic confidence-that is, the Az-was 0.820 before versus 0.968 after review of the contrast-enhanced scan for reader 1 and 0.831 before versus 0.978 after review of the contrast-enhanced scan for reader 2. CONCLUSION: The use of contrast-specific modes with a sulfur hexafluoride contrast agent led to improved characterization of solid focal liver lesions.     

Value of contrast-enhanced sonography for the characterization of focal hepatic lesions in patients with diffuse liver disease: receiver operating characteristic analysis

OBJECTIVE: Our aim was to assess the diagnostic performance of contrast-enhanced agent detection sonographic imaging to characterize focal hepatic lesions in patients with diffuse liver disease in comparison with baseline sonographic images and to determine whether agent detection imaging can reduce the necessity of further diagnostic workup for lesion characterization. MATERIALS AND METHODS: Contrast-enhanced sonography using 4 g of Levovist at a concentration of 300 mg/mL was performed on 75 focal hepatic lesions in 75 patients with diffuse liver disease. Interval reviews for both baseline without and with contrast-enhanced sonography were performed independently by two radiologists. They were requested to determine the malignity of focal hepatic lesions using a 5-point confidence level and to record the specific diagnoses and the necessity for further imaging for lesion characterization. Radiologists' performances for lesion differentiation using baseline and contrast-enhanced sonography were evaluated using receiver operating characteristic (ROC) analysis. Interobserver agreement was also analyzed. RESULTS: When contrast-enhanced sonography was used, ROC analysis revealed a significant improvement for both reviewers (area under the receiver operating characteristic curve [A(z)] = 0.753 and 0.830 and 0.971 and 0.974 at baseline sonography and contrast-enhanced sonography, respectively; p < 0.002) for differentiating malignant and benign focal liver lesions. Contrast-enhanced sonography also improved specificity from 12% to 91% for reviewer 1 and from 26% to 85% for reviewer 2 compared with baseline sonography. Furthermore, excellent interobserver agreement was achieved for contrast-enhanced sonography (weighted kappa = 0.919), whereas only good agreement was achieved for baseline sonography (weighted kappa = 0.656). A better result for specific diagnosis was obtained by contrast-enhanced sonography (79% and 75%) than by baseline sonography (37% and 48%, p < 0.05). Contrast-enhanced sonography (72% and 63%) outperformed baseline sonography (35% and 28%, p < 0.05) as a confirmatory imaging technique. CONCLUSION: Contrast-enhanced agent detection sonography can be used to characterize focal hepatic lesions in patients with diffuse liver disease reliably and with a higher diagnostic confidence than baseline sonography. Furthermore, contrast-enhanced sonography reduced the need for further diagnostic workups for focal hepatic lesion characterization.     

Complex cystic renal masses: characterization with contrast-enhanced US

PURPOSE: To prospectively compare contrast material-enhanced ultrasonography (US) with computed tomography (CT) in the classification of complex cystic renal masses with the Bosniak system. MATERIALS AND METHODS: Ethics committee approval and written informed consent were obtained. Forty patients (17 women, 23 men; age range, 31-77 years) with 44 complex cystic renal masses detected with conventional US were prospectively examined by using second-harmonic US with a second-generation contrast agent and multiphasic helical CT. Thirty-six patients had one lesion, and four patients had two lesions. Surgical resection in nine patients and imaging follow-up in 31 patients were used to determine the outcome. RESULTS: On contrast-enhanced US images, masses were classified as Bosniak category II (n = 18), IIF (ie, lesions were classified as category II and follow-up was needed) (n = 16), III (n = 7), or IV (n = 3) lesions. On CT images, masses were classified as Bosniak category II (n = 24), IIF (n = 10), III (n = 7), or IV (n = 3) lesions. Interobserver agreement was high (kappa = 0.86, P < .001) for classification with US. Complete concordance between the readers was found for classification with CT. Complete concordance between contrast-enhanced US and CT was observed in the differentiation of surgical and nonsurgical complex cysts. Complete concordance among the three readers in the assessment of vascularity with contrast-enhanced US was found. Interobserver agreement in the evaluation of enhancement on CT images was high (kappa = 0.88, P < .001). Concordance between contrast-enhanced US and CT in the evaluation of vascularization was high (kappa = 0.77, P < .001). CONCLUSION: The study data suggest that contrast-enhanced second-harmonic US is appropriate for renal cyst classification with the Bosniak system.     

Perirenal Fluid in Renal Parenchymal Medical Disease (‘Floating Kidney’): Clinical Significance and Sonographic Grading

AIM: To study the clinical significance and radiologic features of perirenal fluid in patients with renal parenchymal disease. MATERIALS AND METHODS: During the previous 5 years, nine patients were found to have perirenal fluid on sonography associated with renal parenchymal medical disease. The clinical, radiological, histopathological and laboratory data were analysed. RESULTS: The perirenal fluid is a spontaneous subcapsular transudate in patients suffering from a nephropathy with a sodium retention state, with or without renal failure. Three sonographic patterns of perirenal fluid were observed: grade 1 is a thin layer of perirenal fluid; grade 2 is a moderate amount of perirenal fluid collection with indentations of the renal parenchyma and strands in the fluid, grade 3 is a large fluid collection surrounding the kidney. CONCLUSION: The perirenal fluid represents a sign of sodium retention state and oedema in patients with intrinsic renal parenchymal medical disease which may be caused by several nephropathies. Haddad, M. C.et al. (2001). Clinical Radiology56, 979–983.     

Detection and characterization of focal liver lesions with contrast-enhanced ultrasonography in patients with hepatitis C-induced liver cirrhosis

Background: Hepatitis C virus (HCV)-associated liver cirrhosis provides a major preneoplastic condition for hepatocellular carcinoma (HCC). Ultrasonography (US) is usually used for screening of HCC, but needs improvement.

Purpose: To assess whether use of a second-generation ultrasound contrast agent can improve characterization of focal liver lesions and detection of HCC in HCV-infected patients with liver cirrhosis.

Material and Methods: In total, 96 US studies in 49 HCV-infected patients with liver cirrhosis were performed. The patients were first examined with a baseline US. After this, a diagnostic decision was made and recorded. The patients were then re-examined with contrast-enhanced ultrasound (CEUS), and the diagnostic triage was repeated. The patients were followed up for at least 1 year.

Results: On baseline US, indeterminate focal lesions were found in 27 examinations. After CEUS, a confident diagnosis of HCC was made in eight of these examinations. In an additional eight US examinations, diagnosis of regenerative/dysplastic noduli was established. In one patient with no detectable focal lesion at baseline examination, an indeterminate malignant lesion was detected with CEUS. This lesion was further investigated with computed tomography and diagnosed as HCC.

Conclusion: Our study indicates that the use of CEUS significantly improves diagnostic confidence. CEUS improves the detection of HCC in patients with HCV-induced liver cirrhosis. Also, CEUS makes it possible to rule out malignancy in many cases where baseline US shows indeterminate focal lesions. In low-endemic countries, the use of CEUS in screening for HCC may be considered.     

Sonographic detection of acute parenchymal injury in an experimental porcine model of renal hemorrhage: gray-scale imaging using a sonographic contrast agent.

OBJECTIVE: The purpose of this study was to determine the usefulness of contrast-enhanced sonography in the detection of acute parenchymal injury. SUBJECTS AND METHODS: In a model of acute renal injury in pigs, four separate renal parenchymal bleeds were created by puncturing an interlobar artery of the upper and lower poles of the kidneys. B-mode gray-scale scans of the kidneys before and after injury, and after the administration of i.v. and intraarterial (i.a.) contrast agents were recorded on videotape for 5 min for each condition (baseline, after injury, after i.v. contrast administration, and after i.a. contrast administration). For each condition and injury, selected frames were analyzed with regions of interest of the normal renal parenchyma, the area of injury, and the perinephric space. Randomized videotape clips from each of the experimental conditions were rated by three sonologists as to the presence or absence of increased intrarenal parenchymal echogenicity, perinephric echogenicity, and confidence as to whether renal injury was present. RESULTS: Areas of renal injury were isoechoic with normal parenchyma on unenhanced scans. After both i.v. and i.a. contrast material injection, areas of injury were visible as areas of increased echogenicity. Contrast increased from 0.2 on unenhanced images to 4.0 and 4.5, respectively, after i.v. and i.a. administration of the new contrast agent. The three observers' ability to diagnose renal injury increased from 0.61, 0.64, and 0.54 to 0.71, 0.70, and 0.74 after i.v. injection and to 0.93, 0.92, and 0.97 after i.a. injection as indicated by the area under the curve in the receiver operating characteristic analysis. CONCLUSION: Transabdominal contrast-enhanced gray-scale sonography can reveal the area of acute renal hemorrhage. This procedure may be applicable in patients when sonographic contrast agents, imaging procedures, and modes of contrast administration are optimized for clinical use in trauma.     

Contrast-enhanced second-harmonic sonography in the detection of pseudocapsule in renal cell carcinoma

OBJECTIVE: Our purpose was to assess the capacity of contrast-enhanced second-harmonic sonography to detect a pseudocapsule in renal masses compared with conventional gray-scale sonography. SUBJECTS AND METHODS. Thirty-two patients with 40 renal masses suspicious for renal cancer (mean diameter, 3.1 cm) were prospectively studied with contrast-enhanced second-harmonic sonography during IV administration of a second-generation sonographic contrast agent. The sonographic criteria for the presence of a pseudocapsule were a peritumoral hypoanechoic halo on conventional gray-scale imaging and a rim of perilesional enhancement, increasing in the tardive phase of the examination, on contrast-enhanced second-harmonic imaging. Multiphasic helical CT or dynamic MRI or both were performed in all patients. RESULTS: Final diagnoses of the 40 renal masses were as follows: hemorrhagic cysts, five; angiomyolipomas, four; lymphomas, four; metastasis from lung cancer, one; and renal cell carcinomas (RCCs), 26. Histologic diagnosis of RCC was surgically obtained in all patients. Nephron-sparing surgery was performed in 12 of 26 RCCs, and radical nephrectomy was performed in the remaining 14. At pathologic examination, pseudocapsule was found in 14 (53.8%) of 26 RCCs. On conventional sonography, the presence of a pseudocapsule was detected in 3 of 14 RCCs (sensitivity, 21%). Sonographic contrast-enhanced harmonic imaging revealed the presence of pseudocapsule in 12 of 14 RCCs (sensitivity, 85.7%). In the remaining 12 RCCs with either absent or extensive neoplastic infiltration of pseudocapsule seen at pathologic evaluation, pseudocapsule was not visible on either conventional or contrast-enhanced second-harmonic sonography. The pseudocapsule was not visible in any of the 14 noncancerous renal masses on either conventional or contrast-enhanced sonography. CONCLUSION: Sonographic contrast-specific imaging with a second-generation contrast agent is effective in improving the sonographic visualization of tumoral pseudocapsule. This finding could be useful both in the sonographic diagnosis and in the choice of conservative surgery for renal cell carcinoma. The potential role of second-harmonic contrast-enhanced sonography in the management of renal cell carcinoma should be investigated in larger series and compared with the findings of state-of-the-art MRI and CT.     

Use of the sonographic contrast medium in the study of pelvic masses: preliminary remarks

PURPOSE: To evaluate the role of intravenously injected sonographic contrast medium (CM) in characterising space-occupying pelvic lesions. MATERIALS AND METHODS: Forty-seven women with palpable pelvic mass underwent color Doppler US before and after the intravenous injection of an ultrasound CM. The examination results were divided into three categories: Class I = no additional diagnostic information supplied by the contrast-enhanced examination; Class II = the use of CM facilitated the identification of vascular structures but did not significantly affect the diagnosis or the patient's subsequent diagnostic/therapeutic procedures; Class III = the information obtained significantly affected treatment decisions regarding the single patients. RESULTS: After the CM injection, 9/47 (19.1%) cases were assigned to Class I, 25/47 (53.2%) to Class II, and 13/47 (27.7%) to Class III. At baseline, all 13 lesions later assigned to Class III had shown an avascular appearance or only peripheral vascularisation. This type of vascular distribution was confirmed by the contrast-enhanced study, which helped determine the haemorrhagic nature (with solid appearance) of some lesions, or support the hypothesis put forward during the baseline study, that the lesion was a poorly vascularised benign mass. This lent further support to our choice to undertake a laparoscopic surgical approach in 2 lesions, it altered our decision as to the type of surgery to be performed (laparoscopy vs. laparotomy) in 5 patients, and confirmed our intention to undertake only the follow-up in the 6 remaining cases. CONCLUSIONS: The use of the sonographic CM proved clinically useful in 13/47 patients with space-occupying pelvic lesions. The most important result of this examination was its ability to confirm the nonvascular or poorly vascular component of a lesion, and therefore to suggest its benign nature.     

Contrast enhanced ultrasound with second generation contrast agent in traumatic liver lesions

PURPOSE: To evaluate the accuracy of second generation contrast enhanced US (Sonovue) in the diagnosis and staging of traumatic hepatic lesions, compared with conventional US and spiral CT. MATERIAL AND METHODS: A total of 203 patients (127 males, 76 females, mean age 36 years) with isolated abdominal trauma were examined with conventional and contrast enhanced US (Sonovue, Bracco, Italy) between March 2002 and February 2003. The sonographic contrast agent was administered at a dose of 2 ml/10-15", repeated twice. CT examinations were performed with single- (Rhota, Esaote Biomedica, Italy) or multislice spiral CT with administration of contrast agent. The presence and number of lesions, hepatic capsular involvement, size and sonographic pattern were evaluated. RESULTS: Conventional US demonstrated hepatic lesions in 27 patients, in 3 cases it identified 2 foci (30 lesions, size 2-8 cm). Contrast enhanced US (CEUS) revealed another 2 lesions and in 4 patients it identified lesions not shown at conventional US (size 2-5 cm). Capsular involvement was detected in 14 cases (11 with conventional US). The sonographic pattern of the lesions at conventional US was hypo-anechoic in 19 cases, and hyperechoic in 11. In CEUS all the lesions appeared strongly hypoechoic against a strongly hyperechoic parenchyma, with clear borders and larger size as compared with conventional US. CONCLUSIONS: In isolated blunt abdominal trauma CEUS is more accurate than conventional US in determining the number and size of lesions and detecting capsular involvement. This has a strong impact on diagnosis as the number of false negatives is reduced and on prognosis as the lesions are more accurately graded, and there is close correlation with spiral CT. CEUS can be used as a first approach in mild isolated abdominal trauma, in paediatric patients and in the follow-up, whereas CT is the method of choice in severe trauma and in multiple traumas.     

Color power Doppler US and contrast-enhanced US features of abdominal solid organ injuries

Utilization of color power Doppler and sonographic contrast agents to basic ultrasound (US) further improve the detection and characterization of abdominal injuries, increasing the diagnostic accuracy and value of US as an important technique in the evaluation of the abdominal trauma. This paper provides an illustrated summary of our clinical experience with color power Doppler US (CD-US) and contrast-enhanced US (CE-US) in the evaluation of abdominal solid organ injuries, involving 32 documented cases over a 2-year period. The findings of the CD-US and CE-US were compared with those provided by state-of-the-art contrast-enhanced multidetector 16-row CT.     

Abdominelles Polytrauma und Parenchymorgane

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.     

Second-generation sonographic contrast agent for differential diagnosis of perisplenic lesions

OBJECTIVE: On contrast-enhanced sonography, second-generation contrast media have shown a spleen-specific uptake of the microbubble contrast agent. To date, there is little data about the diagnostic value of contrast-enhanced sonography in perisplenic lesions. CONCLUSION: In patients with a perisplenic tumor of unknown cause, contrast-enhanced sonography enables the diagnosis or exclusion of accessory spleens.     

Computed tomography of renal lymphoma

The CT studies of 29 patients with renal or perirenal lymphoma were retrospectively reviewed. Four patterns of disease were identified. Seventeen of 29 patients (59%) had bilateral renal masses. Only seven of these patients had associated enlarged retroperitoneal lymph nodes. Eight patients (28%) had single renal or perirenal lesions adjacent to or contiguous with bulky retroperitoneal lymphadenopathy. Three patients had infiltration of the perirenal space without significant renal parenchymal involvement, and one patient had a solitary renal mass. No patients in this series had diffuse involvement of the kidney without a focal mass. Renal involvement with lymphoma should be considered in any patient who develops multiple homogeneous solid renal or perirenal masses, even in the absence of other retroperitoneal disease.     

Computed tomography of ureteral disruption

Computed tomography in four cases of urine extravasation due to ureteropelvic disruption secondary to blunt trauma were compared with CT in 15 cases of renal parenchymal injury. In three cases of isolated ureteropelvic disruption the renal parenchyma was intact; contrast medium excretion was normal; no perirenal hematoma was present. Contrast medium extravasation was confined predominantly to the medial perirenal space. The ipsilateral ureter was not opacified in three of the four cases of ureteropelvic disruption. These CT findings of ureteral injury are distinct from those of renal parenchymal injury. When these findings are present on CT done for trauma, confident diagnosis of ureteral disruption can be made. In one case, combined renal parenchymal injury and ureteropelvic disruption occurred.