Ultrasound imaging is clinically established for routine screening examinations of breast, abdomen, neck, and other soft tissues, as well as for therapy monitoring. Microbubbles as vascular contrast agents improve the detection and characterization of cancerous lesions, inflammatory processes, and cardiovascular pathologies. Taking advantage of the excellent sensitivity and specificity of ultrasound for microbubble detection, molecular imaging can be realized by binding antibodies, peptides, and other targeting moieties to microbubble surfaces. Molecular microbubbles directed against various targets such as vascular endothelial growth factor receptor-2, vascular cell adhesion molecule 1, intercellular adhesion molecule 1, selectins, and integrins were developed and were shown in preclinical studies to be able to selectively bind to tumor blood vessels and atherosclerotic plaques. Currently, the first microbubble formulations targeted to angiogenic vessels in prostate cancers are being evaluated clinically. However, microbubbles can be used for more than diagnosis: disintegrating microbubbles emit acoustic forces that are strong enough to induce thrombolysis, and they can also be used for facilitating drug and gene delivery across biologic barriers. This review on the use of microbubbles for ultrasound-based molecular imaging, therapy, and theranostics addresses innovative concepts and identifies areas in which clinical translation is foreseeable in the near future.
\"A very useful aspect of this book, particularly for students, is the presentation of normal as well as pathologic ultrasonographic findings side-by-side with their angiographic \"gold-standard\" findings. For the clinician, the case scenarios are quite useful in helping to demonstrate the clinical use of ultrasonography. This is a high quality publication with good theoretical descriptions of how ultrasonography can be best used and excellent illustrations to accompany the text. The applications are up-to-date and thus make the book a useful addition to any vascular labor radiology suite.\" Doody's review, April 2006.
In abdominal ultrasonography, abdominal aortic aneurysms (AAAs) are found in 2% to 8% of men over the age of 65 years, with incidence in women that is lower by a factor of 4 . All AAAs are defined as an enlargement of the abdominal aorta greater than 3.0 cm or greater than 50% of normal size . About 85% of all AAAs are detected below the origin of the kidney vessels . Surgical intervention is recommended at any diameter greater than 5.5 cm in men or 5.0 cm in women . The main risk is a rupture, with a risk of less than 1% for aneurysms with a size of less than 5.5 cm, 10% for aneurysms with a diameter between 5.5 cm and 7.0 cm, and 33% for aneurysms larger than 7.0 cm . A ruptured AAA shows a mortality rate of 85% to 90% . Clinical management includes conservative treatment with follow-up ultrasonography for asymptomatic AAAs with a diameter less than 5.5 cm, as there is a higher risk of peri-interventional complications than of rupture and surgical repair for AAAs above that size, with contrast-enhanced ultrasonography (CEUS) follow-up examinations after endovascular aneurysm repair (EVAR) [20-28].
A. B-Scan shows a high-degree internal carotid artery (ICA) stenosis with soft plaques (arrow). B, C. Duplex ultrasonography shows a high-degree stenosis of the ICA (arrowhead) with a maximal systolic flow velocity of about 500 cm/sec. D. Contrast-enhanced ultrasonography (CEUS) detects the intrastenotic flow (arrowhead) without overwriting the wall of the vessel and reveals the complete residual lumen and the length of the stenosis. Additionally, CEUS confirms the absence of intraplaque neovascularization (arrow).
A. B-Scan of show a significant stenosis by atheromatous plaques (arrows). B. Contrast-enhanced ultrasonography shows a neovascularization inside the plaque (arrowhead) as a sign of plaque vulnerability.
Vascular anomalies are congenital lesions of abnormal vascular development, and a primary distinction have to be made between a vascular tumor and a vascular malformation, hemangiomas are considered the commonest vascular tumor, correct diagnosis is imperative for appropriate treatment. In this report, we tried to verify the role of ultrasonography and Doppler examination in the initial diagnosis, the classification of vascular anomalies and in the post-treatment follow-up.
All patients had standardized ultrasonography of the vascular soft tissue swelling with that excess gel was used. Linear high frequency probes were used to perform ultrasound examinations, then color Doppler examinations were performed, examination of the lesions were done with special techniques as Valsalva maneuver, compression of the lesion and limb dependency as needed.
Arterial duplex ultrasonography is noninvasive and readily available in the vascular laboratory as a useful adjunct to non-invasive physiologic testing. However, it is time-consuming and operator dependent, and thus should not be used as the primary diagnostic tool for the detection of PAD. Instead, it is typically obtained for more focused evaluation of the lower extremity arterial system such as localization of stenosis, assessment of stent or bypass graft patency, and detection of pseudoaneurysms or arteriovenous fistulas. Arterial duplex allows for direct plaque visualization with assessment of hemodynamics to establish stenosis severity. Spectral Doppler interrogation reveals elevated flow velocities at the site of (or just distal to) the stenosis, with a doubling of velocities compared to a more normal proximal segment suggestive of a hemodynamically significant lesion (FIGURE 3A). Spectral Doppler waveforms distal to the stenosis are monophasic and display a tardus et parvus pattern with delayed upstroke and low velocity (FIGURE 3B). 781b155fdc