Detection of bleeding in injured femoral arteries with contrast-enhanced sonography.

OBJECTIVE: The purpose of this study was to investigate the feasibility of detecting acute arterial bleeding by means of contrast-enhanced sonography. METHODS: Puncture injury was produced transcutaneously with an 18-gauge needle in 26 femoral arteries (13 in the control group and 13 in the contrast-enhanced group) of rabbits. A sonographic contrast agent (Optison; Mallinckrodt Inc, St Louis, MO) was administered intravenously at a dose of 0.06 to 0.07 mL/kg. Sonography of the femoral arteries was performed before and after injury, both before and after injection of Optison, with B-mode imaging, color Doppler imaging, and pulse inversion harmonic imaging (PIHI). RESULTS: The specific location of active bleeding could not be visualized in B-mode and PIHI scans in the control group (no Optison injection). After administration of Optison, the bleeding site was visualized because of the increased echogenicity of the extravasated blood at the puncture site in both B-mode imaging and PIHI. In color Doppler images, bleeding sites were localized successfully in 84.6% of the cases in the presence of Optison and in 30.8% of the cases without Optison. Histologic examination (light microscopy) of the hematoma confirmed the presence of contrast agent microbubbles in the extravascular space surrounding the artery. CONCLUSIONS: Contrast-enhanced sonography may provide an effective method for detecting arterial bleeding.     

The role of late-phase pulse inversion harmonic imaging in the detection of occult hepatic metastases.

OBJECTIVE: The purpose of this study was to investigate the efficacy of late-phase pulse inversion harmonic imaging (PIHI) in detecting occult metastases and to compare the results with helical computed tomography (CT) in a group of patients whose fundamental liver sonographic results were normal. METHODS: Thirty-two patients (21 women and 11 men; age range, 20-87 years) with a known primary malignancy were enrolled in the study. The patients were evaluated with conventional sonography, unenhanced PIHI, and PIHI 3 minutes after the injection of Levovist (SH U 508A; Schering AG, Berlin, Germany). All patients also underwent triphasic helical CT within 1 week after sonography. In 1 patient, mangafodipir-enhanced magnetic resonance imaging was performed as part of the clinical workup. RESULTS: After Levovist injection, in 4 (12.5%) of 32 patients, at least 1 hypoechoic lesion was detected by PIHI; multiple lesions were shown in 1 patient. The mean diameter of newly detected lesions was 12 mm. Triphasic helical CT also showed all of the lesions that were detected by PIHI. The diagnoses were confirmed by biopsy and CT findings in 2 patients and by the typical CT and magnetic resonance imaging findings in 1 patient. For the fourth patient, the diagnosis was confirmed by follow-up and CT. Conclusions. Late-phase PIHI is comparable to helical CT for detecting occult hepatic metastases, but it protects patients from the potentially hazardous effects of radiation and iodinated contrast agents. Further series involving a larger number of patients are needed to determine its place in the evaluation of cancer staging and treatment planning.     

Characterization of hyperechoic focal liver lesions: quantitative evaluation with pulse inversion harmonic imaging in the late phase of levovist.

OBJECTIVE: The aim of this study was to evaluate hyperechoic focal liver lesions with pulse inversion harmonic imaging in the late phase of SH U 508A (Levovist; Schering AG, Berlin, Germany) and to determine whether quantitative evaluation improves the characterization of the lesions. METHODS: Twenty-six patients with hyperechoic liver lesions were enrolled in this study. Pulse inversion harmonic imaging was performed before and after administration of Levovist. Scan data were digitally stored, and each lesion was analyzed with a personal computer-based quantification package. All lesions were confirmed by histologic or triphasic spiral computed tomographic examinations. The intensity was measured in decibels in regions of interest drawn within the lesion and surrounding liver parenchyma. The lesion-liver ratios were than calculated. After contrast agent administration, a ratio equal to or greater than 1 was presumed benign, whereas a ratio of less than 1 was considered malignant. RESULTS: Nine malignant (7 metastases, 1 hepatocellular carcinoma, and 1 cholangiocarcinoma) and 17 benign (14 hemangioma, 1 focal nodular hyperplasia, 1 focal fatty change, and 1 inflammatory pseudotumor) hyperechoic lesions were quantitatively evaluated. All malignant (n = 9) and 2 benign lesions (1 hemangioma and 1 inflammatory pseudotumor) had ratios of less than 1. In 15 of 17 benign lesions, the ratios were equal to or greater than 1. The intensity ratios calculated for benign and malignant lesions showed a statistically significant difference (P < .05). CONCLUSIONS: Pulse inversion harmonic imaging with quantitative evaluation facilitates the differential diagnosis of hyperechoic focal liver lesions. A lesion-liver ratio equal to or greater than 1 predicts a benign nature, assuming that malignant lesions show a ratio of less than 1.     

Comparing differential tissue harmonic imaging with tissue harmonic and fundamental gray scale imaging of the liver.

OBJECTIVE: The purpose of this study was to compare fundamental gray scale sonography, tissue harmonic imaging (THI), and differential tissue harmonic imaging (DTHI) for depicting normal and abnormal livers. METHODS: The in vitro lateral resolution of DTHI, THI, and sonography was assessed in a phantom. Sagittal and transverse images of right and left hepatic lobes of 5 volunteers and 20 patients and images of 27 liver lesions were also acquired. Three independent blinded readers scored all randomized images for noise, detail resolution, image quality, and margin (for lesions) on a 7-point scale. Next, images from the same location obtained with all 3 modes were compared blindly side by side and rated by all readers. Contrast-to-noise ratios were calculated for the lesions, and the depth of penetration (centimeters) was determined for all images. RESULTS: In vitro, the lateral resolution of DTHI was significantly better than fundamental sonography (P = .009) and showed a trend toward significance versus THI (P = .06). In the far field, DTHI performed better than both modes (P < .04). In vivo, 450 images were scored, and for all parameters, DTHI and THI did better than sonography (P < .002). Differential tissue harmonic imaging scored significantly higher than THI with regard to detail resolution and image quality (P < .001). The average increase in penetration with THI and DTHI was around 0.6 cm relative to sonography (P < .0001). The contrast-to-noise ratio for DTHI showed a trend toward significance versus THI (P = .06). Side-by-side comparisons rated DTHI better than THI and sonography in 54% of the cases (P < .007). CONCLUSIONS: Tissue harmonic imaging and DTHI do better than fundamental sonography for hepatic imaging, with DTHI being rated the best of the 3 techniques.     

Phase inversion harmonic imaging improves assessment of renal calculi: a comparison with fundamental gray-scale sonography

PURPOSE: To compare phase inversion harmonic imaging (PIHI) with fundamental imaging (FI) in the evaluation of renal calculi. METHODS: Thirty adult patients with renal calculi (17 men, 13 women; mean age 44 years [range, 25-71]) underwent transabdominal sonographic examination of the urinary system. Both kidneys and renal calculi were examined with PIHI and FI. Overall renal conspicuity, calculus visibility, and clarity of posterior shadowing were assessed subjectively using a 4-point scale (0 being the worst, 3 being the best). The maximum diameter of the calculi was measured using both techniques. The effect of body mass index on qualitative scoring and quantitative measurements was evaluated. RESULTS: PIHI improved overall renal conspicuity compared with FI (p < 0.001). The visibility of the calculi and clarity of posterior shadowing were significantly better with PIHI than with FI (p < 0.001 for both parameters). The maximum diameter of calculi was larger with PIHI than with FI (p < 0.001). The superiority of PIHI over FI regarding overall conspicuity of the kidney, visibility of the calculus, and clarity of posterior shadowing scores increased in the obese group (p < 0.001 for all 3 parameters). The mean calculus diameter difference between the 2 techniques was significantly higher in the obese group. CONCLUSION: The routine use of PIHI is recommended in the evaluation of renal calculi.     

Outcome of fetuses with clubfeet diagnosed by prenatal sonography.

OBJECTIVE: To determine the outcome of fetuses with clubfoot diagnosed by prenatal sonography. METHODS: We identified all fetuses scanned at our institution from May 1989 to May 2002 in whom clubfoot was suspected or diagnosed on prenatal sonography. From maternal and neonatal medical records, we collected the following information when available: unilateral or bilateral clubfoot, gestational age at diagnosis, other sonographic findings, and pregnancy outcome, including pathologic reports and neonatal findings at birth. RESULTS: One hundred twenty-one fetuses had prenatal sonographic suspicion or diagnosis of clubfoot. Twenty-two had no follow-up information, and 12 fetuses were terminated with fetal parts that could not be evaluated at pathologic examination, leaving 87 study cases. Outcome information was from neonatal records in 51 and from pathologic reports in 36. The gestational age at diagnosis ranged from 12.3 to 39.2 weeks, with a mean of 22.2 weeks. Forty-two (48%) had unilateral clubfoot, and 45 (52%) had bilateral clubfoot on sonography. The false-positive rate was significantly higher with unilateral clubfoot than bilateral clubfoot (12 [29%] of 42 versus 3 [7%] of 45; P < .05). Other anomalies were more common with bilateral clubfoot than with unilateral clubfoot (34 [76%] of 45 versus 23 [55%] of 42; P < .05), the most common being other musculoskeletal anomalies, neural tube defects, and cardiovascular anomalies. Of fetuses with information about chromosomes, the rates of aneuploidy were similar for unilateral and bilateral clubfoot (5 [28%] of 18 versus 10 [32%] of 31; P > .05). CONCLUSIONS: Fetuses with an antenatal sonographic diagnosis of clubfoot often have other anomalies, aneuploidy, or both. The false-positive rate for diagnosis of clubfoot is higher for unilateral clubfoot than bilateral clubfoot. The rate of associated anomalies is higher with bilateral clubfoot than unilateral clubfoot.     

Advantages of color B-mode imaging with contrast optimization in sonography of low-contrast musculoskeletal lesions and structures in the foot and ankle.

OBJECTIVE: The purpose of this study was to evaluate the utility of color B-mode imaging with contrast optimization in evaluating low-contrast lesions of the foot and ankle (Morton neuromas and plantar fasciitis). METHODS: The sonographic examinations of 49 consecutive patients with a diagnosis of plantar fasciitis or Morton neuroma imaged with both conventional gray scale imaging and color B-mode imaging with contrast optimization (Photopic; Siemens Medical Solutions, Mountain View, CA) were reviewed. In every patient, matched pairs of images obtained with conventional gray and color maps (Photopic) were acquired and stored as DICOM (Digital Imaging and Communications in Medicine) images on a sonographic workstation. Each image was assessed independently by 2 musculoskeletal radiologists trained in musculoskeletal sonography for overall image contrast (lesion to background), conspicuity of regional tissue boundaries, visualization of deep tissue boundaries, and how well the internal characteristics of the structure were visualized. RESULTS: Three-way analysis of variance showed that Photopic imaging resulted in statistically significantly improved overall image contrast, definition of regional soft tissue boundaries, including deep soft tissue boundaries, and depiction of the internal characteristics of the structure being examined. CONCLUSIONS: Color imaging with contrast optimization improves overall image contrast and better defines deep soft tissue boundaries and the internal morphologic characteristics of Morton neuromas and the plantar fascia compared with conventional gray scale imaging.     

Tissue harmonic imaging: utility in breast sonography.

OBJECTIVE: To determine the impact of tissue harmonic imaging on visualization of focal breast lesions and to compare gray scale contrast between focal breast lesions and fatty tissue of the breast between tissue harmonic imaging and fundamental frequency sonography. METHODS: A prospective study was performed on 219 female patients (254 lesions) undergoing sonographically guided fine-needle biopsy. The fundamental frequency and tissue harmonic images of all lesions were obtained on a scanner with a wideband 7.5-MHz linear probe. Twenty-three breast carcinomas, 6 suspect lesions, 9 fibroadenomas, 1 papilloma, 1 phyllodes tumor, 162 unspecified solid benign lesions, and 40 cysts were found. In 12 cases the fine-needle aspiration did not yield sufficient material. The gray scale intensity of the lesions and adjacent fatty tissue was measured with graphics software, and the gray scale contrast between lesions and adjacent fatty tissue was calculated. RESULTS: Tissue harmonic imaging improved the gray scale contrast between the fatty tissue and breast lesions in 230 lesions (90.6%; P < .001) compared with fundamental frequency images. The contrast improvement was bigger in breasts with predominantly fatty or mixed (fatty/glandular) composition than in predominantly glandular breasts. The overall conspicuity, lesion border definition, lesion content definition, and acoustic shadow conspicuity were improved or equal in the harmonic mode for all lesions.CONCLUSIONS: The tissue harmonic imaging technique used as an adjunct to conventional breast sonography may improve lesion detectability and characterization.     

Splenic trauma: evaluation with contrast-specific sonography and a second-generation contrast medium: preliminary experience.

OBJECTIVE: To report our experience in the assessment of splenic trauma with contrast-coded sonography and a second-generation contrast medium. METHODS: From January to May 2002, 120 patients were studied with sonography for suspected splenic trauma. Twenty-five were selected for further imaging because of sonographic findings positive for splenic injury, findings positive for peritoneal fluid only, indeterminate findings, and negative findings with high clinical or laboratory suspicion. These patients underwent contrast-enhanced harmonic sonography and contrast-enhanced helical computed tomography. RESULTS: Among the 25 patients studied, 6 had no spleen trauma at initial and follow-up evaluation. One patient had a hypoperfused spleen without parenchymal damage, and 18 had splenic injuries; these 19 patients were considered positive. Hemoperitoneum was identified by sonography, contrast-enhanced sonography, and contrast-enhanced computed tomography in 74% of the 19 positive cases. Perisplenic clots were recognized in 58% of the cases by computed tomography and in 42% by baseline and enhanced sonography. Splenic infarctions were found in 11% of cases by contrast-enhanced sonography and computed tomography; none was found by unenhanced sonography. Parenchymal traumatic lesions were identified in 12 of 18 patients with splenic injuries by unenhanced sonography, in 17 cases by contrast-enhanced sonography, and in all 18 cases by contrast-enhanced computed tomography. A minimal splenic lesion was found in the single patient with a false-negative contrast-enhanced sonographic finding. Contrast-enhanced sonography correlated appreciably better than unenhanced sonography in detecting injuries and in estimating their extent. Findings undetectable on unenhanced sonography were also noted: splenic hypoperfusion in 11% of positive cases on both contrast-enhanced sonography and contrast-enhanced computed tomography, contrast medium pooling in 21% of cases on both contrast-enhanced sonography and computed tomography, and contrast extravasation in 11% of cases on computed tomography and 5% on contrast-enhanced sonography. CONCLUSIONS: Contrast-enhanced sonography is a promising tool in the assessment of splenic trauma. In institutions where sonography is used as the initial procedure, this technique may increase its effectiveness.     

Feasibility of contrast-enhanced sonography during resection of cerebral tumours: initial results of a prospective study

The aim of this study was to adapt the ultrasonographical techniques developed for brain perfusion imaging to an intraoperative setting for topographic diagnosis of cerebral tumours. During surgery, the patients underwent contrast-enhanced ultrasonography (phase inversion harmonic imaging, bolus kinetic, fitted model function). Endocavity curved array (6.5EC10, 6.5 MHz) was used intraoperatively. The ultrasound contrast agent SonoVue (Bracco) was administered IV as a bolus injection. Off-line, time-intensity curves as well as perfusion maps were calculated and parameters such as peak intensity were locally extracted to characterise perfusion. Seven patients with brain tumours of different histologic types were subjected to contrast-enhanced ultrasonography during surgery. Tissue differentiation with contrast agent was superior to conventional B-mode ultrasound imaging. Intraoperative contrast-enhanced ultrasonography enabled visualisation of cerebral tumours in high spatial resolution.     

Spectral Doppler sonography of musculoskeletal soft tissue masses.

OBJECTIVE: To determine whether resistive indices obtained from spectral Doppler waveforms can be used to distinguish benign from malignant musculoskeletal soft tissue masses. METHODS: A retrospective review of Doppler sonograms was performed for 52 patients with 53 soft tissue masses. All masses showed internal flow on color or power Doppler sonography, and spectral Doppler sonography yielded waveforms from which resistive indices were calculated. This information was analyzed along with the histologic diagnosis of each lesion with significance set at P > .05. RESULTS: There were 19 benign lesions and 34 malignancies. The resistive indices of the benign masses ranged from 0.44 to 1.0 (mean +/- SD, 0.72 +/- 0.42), whereas the malignant masses had resistive indices ranging from 0.28 to 1.0 (mean, 0.62 +/- 0.36). There was no statistically significant (P > .05) difference between the resistive indices of benign and malignant lesions. CONCLUSIONS: Resistive indices cannot be used to distinguish benign from malignant musculoskeletal soft tissue masses.     

Detection and differential diagnosis of hepatic masses using pulse inversion harmonic imaging during the liver-specific late phase of contrast enhancement with Levovist

PURPOSE: The purpose of this study was to investigate whether late-phase pulse inversion harmonic imaging (PIHI) increases conspicuity in hepatic masses, helps to differentiate benign from malignant lesions, and demonstrates a greater number of and smaller metastatic lesions than do conventional (fundamental) sonography and helical CT. METHODS: Thirty patients (17 women and 13 men; age range, 35-77 years; mean age, 54 years) with known or suspected liver masses were evaluated using both fundamental sonography and contrast-enhanced PIHI during the liver-specific late phase of Levovist. The patients also underwent contrast-enhanced triphasic helical CT examinations within 1 week after sonography. In 4 of the patients, gadolinium-enhanced MRI was also performed as a part of their clinical work-up. RESULTS: The increase in the lesions' conspicuity on PIHI compared with fundamental sonography was significantly greater in malignant lesions than in benign lesions (p< 0.001). An echogenic rim was observed on PIHI in 8 (53%) of 15 malignant lesions. The mean number of metastatic lesions visualized on PIHI (5.5 +/- 5.3) was significantly higher than the mean number visualized on fundamental sonography (2.5 +/- 2.1, p < 0.05). Although lesions as small as 3 mm were observed on PIHI, the mean sizes of the smallest lesions demonstrated using fundamental sonography, PIHI, and helical CT were not significantly different. CONCLUSIONS: Late-phase PIHI is a useful technique for characterizing hepatic lesions and demonstrating both a greater number of and smaller metastases. It may help to differentiate benign from malignant liver masses and may obviate unnecessary and expensive further imaging.     

Contribution of tissue harmonic imaging and frequency compound imaging in interventional breast sonography.

OBJECTIVE: The purpose of this study was to retrospectively compare conventional imaging, frequency compound imaging (CI), and tissue harmonic imaging (THI) in interventional breast sonography. METHODS: Institutional Review Board approval and patient informed consent were not required. The authors reviewed 104 sonographically guided breast procedures in 83 patients. For each biopsy, 4 images obtained with conventional imaging, frequency CI at 10 and 14 MHz (CI10 and CI14), and THI were graded independently by 2 radiologists for lesion conspicuity, needle conspicuity, lesion and needle conspicuity, and overall image quality. Frequency CI at 10 MHz, CI14, and THI were compared with conventional imaging. Different clinical scenarios (fatty versus glandular background, fine needle versus core needle, and oblique versus horizontal needle direction) were evaluated. RESULTS: Statistical analysis showed that for overall image quality, CI10 was the best setting (odds ratios [OR], 3.67 and 7.48). For lesion conspicuity, CI14 (OR, 3.55) and THI (OR, 1.77) improved lesion visibility in a fatty background, whereas THI (OR, 0.26) was very limited in a glandular background. For needle conspicuity, no setting was better than conventional, whereas THI was the least valuable setting (OR, 0.011 and 0.049). For lesion and needle conspicuity, CI10 showed significantly better results than conventional for a dense background (P = .0268 and .4028; OR, 2.435 and 1.383) with 1 reviewer, whereas THI was the least valuable setting (OR, 0.014 and 0.042). CONCLUSIONS: Conventional imaging provided the best assessment of lesion and needle conspicuity. Frequency compounding is a useful setting for dense breast and for fine-needle aspiration. Tissue harmonic imaging has a role in the visualization of a lesion against a fatty background but is of limited value in needle visualization.     

Contrast advanced dynamic flow imaging and contrast pulse subtraction imaging: Preliminary results in hepatic tumors

Purpose

To investigate the usefulness of contrast advanced dynamic flow imaging and contrast pulse subtraction imaging in the intranodular hemodynamics of hepatic tumors.

Materials and Methods

Ten patients underwent contrast advanced dynamic flow imaging and contrast pulse subtraction imaging using Levovist^®, a microbubble contrast agent. Fourteen hepatic tumor nodules were studied: 9 were hepatocellular carcinoma, 1 metastasis, 1 hemangioma, 1 adenomatous hyperplasia, and 2 metastatic lymph nodes of hepatocellular carcinoma. Real-time scanning of contrast advanced dynamic flow imaging and intermittent interval-delay scanning of contrast pulse subtraction imaging were carried out in the early arterial phase, the late vascular phase, and the postvascular phase. The results obtained from contrast advanced dynamic flow imaging and contrast pulse subtraction imaging were compared with those obtained by precontrast power Doppler imaging and three-phase dynamic CT, respectively.

Results

The rate of detection of intranodular vascularity by contrast advanced dynamic flow imaging (93%) or contrast pulse subtraction imaging (93%) was significantly higher than that of precontrast power Doppler imaging (29%) and was as high as that of dynamic CT. Characteristic intranodular hemodynamics were detected in hepatocellular carcinoma, metastasis, hemangioma, and adenomatous hyperplasia with typical appearance of an intranodular blood vessel image in the early arterial phase, a parenchymal stain image in the late vascular phase, and a perfusion defect image in the post-vascular phase.

Conclusion

Contrast advanced dynamic flow imaging and contrast pulse subtraction imaging clearly show the intranodular hemodynamics in hepatic tumors.     

Sonographic evaluation of scapholunate ligament: value of tissue harmonic imaging

PURPOSE: The aim of this study was to compare tissue harmonic imaging (THI) and conventional (fundamental) sonography in the evaluation of the scapholunate ligament (SLL). METHODS: The bilateral SLL of 3 patients with unilateral SLL rupture and the bilateral SLL of 20 volunteers without history of trauma were examined. THI findings were compared with conventional sonographic findings. RESULTS: On conventional sonographic evaluation of 43 normal wrists, the dorsal component of the SLL was partially visible in 10 of the 43 normal wrists (23%) and was completely visible in 33 of 43 (77%) normal wrists. Using THI, the SLL was visible in its entirety in 39 of 43 normal wrists (91%) and was partially visible in 4 of 43 normal wrists (9%). The mean scapholunate distance was 3.3 mm (range, 2.9-4.5 mm) in normal wrists. THI improved visualization of SLL continuity and demonstration of its fibrillar echotexture. In the 3 wrists with clinical and/or radiological evidence of SLL rupture, the SLL was not visible with conventional sonography nor THI; the mean scapholunate distance was 6.1 mm (range, 5.6-6.8 mm). CONCLUSIONS: THI improves visualization of the SLL.     

How sonographic tomography will change the face of obstetric sonography: a pilot study.

OBJECTIVE: This study was undertaken to determine whether 3-dimensional (3D) volume sonography (sonographic tomography) can yield a far quicker and equally accurate anatomic examination of the second-trimester fetus compared with traditional 2-dimensional (2D) scanning. METHODS: Twenty-five consecutive second-trimester fetuses with normal structural surveys on standard 2D imaging underwent 5 standard 3D volume acquisitions each (in the regions of the head, chest, abdomen, face, and lower extremities) immediately after the 2D scan. The 2D and 3D images were subsequently compared in relation to the completeness of the fetal survey, measurements of the biparietal diameter and femur length, and time required to obtain the fetal survey. RESULTS: The structural surveys were complete in 20 of 25 cases using 3D reconstructed volumes. One fetus had an incomplete evaluation of the face on 3D volumes (and limited on 2D imaging because of the prone position of the fetus). The other 4 fetuses with incomplete surveys done on 3D volumes had missing images of a hand or foot. Three-dimensional reconstructions slightly overmeasured the biparietal diameter compared with the 2D reference standard (mean difference, 1.1 mm; P < .001). For femur length, the mean difference was not statistically significant. It took a mean time of 1.1 minutes to obtain the 3D volumes and 5.5 minutes to reconstruct the complete surveys by the 3D volume method. With the standard 2D technique, the structural surveys were done in a mean time of 13.9 minutes. The mean time difference between both methods was 7.3 minutes (P = 2.4 x 10(-9)). CONCLUSIONS: Using 3D volume acquisition, it is feasible to perform and interpret a structural survey in half the time in which a 2D survey is performed. Further research is necessary to standardize the acquisition of volumes to minimize artifacts and produce uniform images.     

时间-空间标记反转脉冲技术在肾脏皮髓质分离中的应用及时间参数优化

目的 探讨磁共振时间-空间双重标记反转脉冲（T-SLIP）技术在肾脏皮髓质分离中的应用及显示肾脏皮髓质分离最佳的黑血翻转时间（BBTI）。方法 选择健康志愿者60名,采用结合T-SLIP脉冲的稳态自由进动序列（SSFP）行上腹部扫描。采用6个BBTI值（800、1 000、1 200、1 400、1 600、1 800 ms）进行冠状位T-SLIP SSFP序列扫描。采用4分法分析图像质量,并通过图像训练算法自动分割肾脏皮髓质区域,分别计算皮髓质的信号强度（SI）,获得不同BBTI值时肾脏皮髓质的相对信号强度比（SIR）,获得最佳BBTI值。结果 BBTI值为1 200 ms时,图像质量的评分最高。不同BBTI值时,SIR差异有统计学意义（P=0.013）,当BBTI为1 200 ms时,SIR值最大,肾皮髓质间SI对比最明显。结论 T-SLIP技术可在不使用对比剂的情况下清晰显示肾脏皮髓质,当BBTI值为1 200 ms时皮髓质分离显示最好。     

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.     

Characterization of benign hepatic tumors arising in fatty liver with SonoVue and pulse inversion US

Background We describe the spectrum of contrast-enhancement patterns of benign hepatic tumors arising in fatty liver on contrast-enhanced ultrasound (US). Methods Sixteen patients (12 women and four men) with 27 benign hepatic tumors (17 hemangiomas, eight focal nodular hyperplasias, and two hepatocellular adenomas) arising in fatty liver underwent baseline and pulse inversion US after administration of SonoVue. Two experienced radiologists evaluated baseline echogenicity and dynamic enhancement pattern of each lesion in comparison with adjacent liver parenchyma. Results After administration of SonoVue, in the arterial phase 13 of 17 hemangiomas showed peripheral globular enhancement and one showed a rim of peripheral enhancement, followed by progressive centripetal fill-in, which was complete in 10 of 14 cases and incomplete in four. Three of 18 hemangiomas showed rapid and complete fill-in in the arterial phase. Eight of eight focal nodular hyperplasias became hyperechoic in comparison with adjacent liver parenchyma in the arterial phase and slightly hyperechoic or isoechoic in the portal venous and delayed phases. Both adenomas showed strong arterial contrast enhancement that became less intense in the portal venous and delayed phases. Conclusion Contrast-enhanced US after administration of SonoVue enables depiction of typical contrast-enhancement patterns in most benign hepatic tumors arising in fatty liver, thus providing useful clues for characterization.     

Characterization of portal vein thrombus with the use of contrast-enhanced sonography.

OBJECTIVES: To select an appropriate treatment regimen, it is essential to accurately characterize the nature of a thrombus. This study prospectively assessed the ability of contrast-enhanced sonography to differentiate between benign and malignant portal vein thrombosis in a population of high-risk patients. METHODS: Fifty-five patients (43 men and 12 women; mean age, 66 years; range, 55-83 years) with thrombi of the portal venous system were examined by power Doppler sonography and contrast-enhanced sonography with the intravenous contrast agent SH U 508A (Levovist; Schering AG, Berlin, Germany). Of the thrombi, 40 were characterized as malignant and 15 as benign. Pulsatile flow in the thrombus on power Doppler sonography and positive enhancement of the thrombus on contrast-enhanced sonography were judged as indications of a malignant thrombus. The sensitivity and specificity of both methods in differentiating the nature of the thrombus were evaluated. RESULTS: The detection of pulsatile flow in a portal vein thrombus as the criterion for diagnosing malignant portal vein thrombus yielded overall sensitivity of 82.5% and specificity of 100%, whereas positive enhancement of the portal vein thrombus itself as a criterion for diagnosing malignancy yielded overall sensitivity and specificity of 100% for each. CONCLUSIONS: Contrast-enhanced sonography can be helpful in discriminating between benign and malignant portal vein thrombi.