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Contrast-enhanced ultrasonography: advance and current status in abdominal imaging.

Chung YE, Kim KW - Ultrasonography (2014)

Bottom Line: The use of second-generation contrast agents in a low-mechanical-index technique enables continuous scanning.Besides the detection and characterization of focal liver lesions, contrastenhanced US is helpful in the monitoring of radiofrequency ablation therapy and in the targeting step of an US-guided biopsy.In spite of the concerns related to its cost-effectiveness, contrast-enhanced US has the potential to be more widely used as a complimentary tool or to substitute the current imaging modalities in some occasions.

View Article: PubMed Central - PubMed

Affiliation: Department of Radiology, Research Institute of Radiological Science, Yonsei University College of Medicine, Seoul, Korea.

ABSTRACT
In the field of contrast-enhanced ultrasonography (US), contrast agents are classified as either first- or second-generation agents depending on the gas within the microbubbles. In the case of first-generation contrast agents, a high-mechanical-index technique is used and only intermittent scanning is possible due to the early destruction of the microbubbles during the scanning. The use of second-generation contrast agents in a low-mechanical-index technique enables continuous scanning. Besides the detection and characterization of focal liver lesions, contrastenhanced US is helpful in the monitoring of radiofrequency ablation therapy and in the targeting step of an US-guided biopsy. Recently, there has been a demand for new criteria to evaluate the treatment response obtained using anti-angiogenic agents because morphologic criteria alone may not reflect the treatment response of the tumor and contrast-enhanced US can provide quantitative markers of tissue perfusion. In spite of the concerns related to its cost-effectiveness, contrast-enhanced US has the potential to be more widely used as a complimentary tool or to substitute the current imaging modalities in some occasions.

No MeSH data available.


Related in: MedlinePlus

A 49-year-old female with vulvar cancer and acute pyelonephritis.A. In the renal parenchyma phase of computed tomography (CT), a wedge-shaped hypo-attenuating lesion was newly detected in the mid pole of the left kidney (arrows). To exclude metastasis, an ultrasonography (US)-guided biopsy was planned. B. On conventional US, the lesion, which was noted on CT, was not detected. C. After contrast enhancement, a poorly enhancing wedge-shaped lesion was detected in the left kidney (arrowheads), enabling the US-guided biopsy.
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f6-usg-14034: A 49-year-old female with vulvar cancer and acute pyelonephritis.A. In the renal parenchyma phase of computed tomography (CT), a wedge-shaped hypo-attenuating lesion was newly detected in the mid pole of the left kidney (arrows). To exclude metastasis, an ultrasonography (US)-guided biopsy was planned. B. On conventional US, the lesion, which was noted on CT, was not detected. C. After contrast enhancement, a poorly enhancing wedge-shaped lesion was detected in the left kidney (arrowheads), enabling the US-guided biopsy.

Mentions: For the differentiation between neoplasms and pseudotumors, such as the column of Bertin or the dromedary hump in the kidney, CEUS can be used. If the enhancement pattern is similar to the adjacent renal parenchyma and there is no mass effect on the renal vessel, the mass of interest is more likely to be a pseudotumor than an actual neoplasm. CEUS can also delineate lesions that are well visualized on CECT but are not noted on conventional grayscale US (Fig. 6). For complex cystic lesions, the presence or absence of enhancing mural nodules and thick irregular septa can be evaluated with CEUS in addition to Doppler US [6]. After kidney transplantation, CEUS can be helpful in the evaluation of vessels and their anastomosis sites if CECT is not feasible due to a renal function that is not yet restored or stabilized (Fig. 7). In the case of pancreatic applications, CEUS is still used to acquire additional information after cross-sectional imaging, rather than for the detection or differentiation of focal pancreatic lesions [16]. Most pancreatic adenocarcinomas appear as hypovascular on CEUS, and CEUS can visualize the tumor margin and the relationship between a tumor and its adjacent vessels more clearly [75,76]. Enhanced mural nodules are very suggestive findings for malignant cystic pancreatic neoplasms, and CEUS can differentiate a mural nodule from a hematoma or a sludge ball [16]. CEUS can improve the visualization of the aortic lumen and an endoleak in patients with abdominal aortic aneurysm or dissection. CT angiography can also accurately detect an endoleak, but CEUS can provide additional information for identifying the endoleak type by a real-time examination (Fig. 8) [16]. Although CECT is still the gold standard for evaluating blunt abdominal trauma, CEUS can be an alternate option in patients with low-energy blunt abdominal trauma in which CECT does not seem mandatory but in which an abdominal evaluation is still needed [6]. In terms of a diffuse liver injury, CEUS can depict injured areas without requiring that patients be moved to the CT room even if conventional B mode US cannot detect any abnormalities in the liver [77].


Contrast-enhanced ultrasonography: advance and current status in abdominal imaging.

Chung YE, Kim KW - Ultrasonography (2014)

A 49-year-old female with vulvar cancer and acute pyelonephritis.A. In the renal parenchyma phase of computed tomography (CT), a wedge-shaped hypo-attenuating lesion was newly detected in the mid pole of the left kidney (arrows). To exclude metastasis, an ultrasonography (US)-guided biopsy was planned. B. On conventional US, the lesion, which was noted on CT, was not detected. C. After contrast enhancement, a poorly enhancing wedge-shaped lesion was detected in the left kidney (arrowheads), enabling the US-guided biopsy.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4282229&req=5

f6-usg-14034: A 49-year-old female with vulvar cancer and acute pyelonephritis.A. In the renal parenchyma phase of computed tomography (CT), a wedge-shaped hypo-attenuating lesion was newly detected in the mid pole of the left kidney (arrows). To exclude metastasis, an ultrasonography (US)-guided biopsy was planned. B. On conventional US, the lesion, which was noted on CT, was not detected. C. After contrast enhancement, a poorly enhancing wedge-shaped lesion was detected in the left kidney (arrowheads), enabling the US-guided biopsy.
Mentions: For the differentiation between neoplasms and pseudotumors, such as the column of Bertin or the dromedary hump in the kidney, CEUS can be used. If the enhancement pattern is similar to the adjacent renal parenchyma and there is no mass effect on the renal vessel, the mass of interest is more likely to be a pseudotumor than an actual neoplasm. CEUS can also delineate lesions that are well visualized on CECT but are not noted on conventional grayscale US (Fig. 6). For complex cystic lesions, the presence or absence of enhancing mural nodules and thick irregular septa can be evaluated with CEUS in addition to Doppler US [6]. After kidney transplantation, CEUS can be helpful in the evaluation of vessels and their anastomosis sites if CECT is not feasible due to a renal function that is not yet restored or stabilized (Fig. 7). In the case of pancreatic applications, CEUS is still used to acquire additional information after cross-sectional imaging, rather than for the detection or differentiation of focal pancreatic lesions [16]. Most pancreatic adenocarcinomas appear as hypovascular on CEUS, and CEUS can visualize the tumor margin and the relationship between a tumor and its adjacent vessels more clearly [75,76]. Enhanced mural nodules are very suggestive findings for malignant cystic pancreatic neoplasms, and CEUS can differentiate a mural nodule from a hematoma or a sludge ball [16]. CEUS can improve the visualization of the aortic lumen and an endoleak in patients with abdominal aortic aneurysm or dissection. CT angiography can also accurately detect an endoleak, but CEUS can provide additional information for identifying the endoleak type by a real-time examination (Fig. 8) [16]. Although CECT is still the gold standard for evaluating blunt abdominal trauma, CEUS can be an alternate option in patients with low-energy blunt abdominal trauma in which CECT does not seem mandatory but in which an abdominal evaluation is still needed [6]. In terms of a diffuse liver injury, CEUS can depict injured areas without requiring that patients be moved to the CT room even if conventional B mode US cannot detect any abnormalities in the liver [77].

Bottom Line: The use of second-generation contrast agents in a low-mechanical-index technique enables continuous scanning.Besides the detection and characterization of focal liver lesions, contrastenhanced US is helpful in the monitoring of radiofrequency ablation therapy and in the targeting step of an US-guided biopsy.In spite of the concerns related to its cost-effectiveness, contrast-enhanced US has the potential to be more widely used as a complimentary tool or to substitute the current imaging modalities in some occasions.

View Article: PubMed Central - PubMed

Affiliation: Department of Radiology, Research Institute of Radiological Science, Yonsei University College of Medicine, Seoul, Korea.

ABSTRACT
In the field of contrast-enhanced ultrasonography (US), contrast agents are classified as either first- or second-generation agents depending on the gas within the microbubbles. In the case of first-generation contrast agents, a high-mechanical-index technique is used and only intermittent scanning is possible due to the early destruction of the microbubbles during the scanning. The use of second-generation contrast agents in a low-mechanical-index technique enables continuous scanning. Besides the detection and characterization of focal liver lesions, contrastenhanced US is helpful in the monitoring of radiofrequency ablation therapy and in the targeting step of an US-guided biopsy. Recently, there has been a demand for new criteria to evaluate the treatment response obtained using anti-angiogenic agents because morphologic criteria alone may not reflect the treatment response of the tumor and contrast-enhanced US can provide quantitative markers of tissue perfusion. In spite of the concerns related to its cost-effectiveness, contrast-enhanced US has the potential to be more widely used as a complimentary tool or to substitute the current imaging modalities in some occasions.

No MeSH data available.


Related in: MedlinePlus