Ultrasound Acoustic Radiation Force Impulse imaging for High Intensity Focused Ultrasound focal spot localization

AbstractMagnetic Drug Targeting (MDT) is a cancer treatment technique that enables a local chemotherapy. In MDT, chemotherapeutic drugs are bound to magnetic nanoparticles and are accumulated in the tumor area by means of an external magnetic field. Unfortunately, a single magnet can only generate a pulling magnetic force. However, in some applications a pushing force on the nanoparticles could be advantageous. One way to realize pushing forces is to exploit the acoustic radiation force based on the nonlinearity of sound propagation in fluid media generated by a high intensity focused ultrasonic transducer. In this context, we built a test setup was built to investigate the utility of High Intensity Focused Ultrasound (HIFU) to generate a pushing force on the magnetic nanoparticles. The results show that the acoustic radiation force can be employed for particle guidance to achieve concentration differences similar to those obtained by using an electromagnet.

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Acoustic Radiation Force Impulse (ARFI) Imaging of the Gastrointestinal Tract

Ultrasonic Imaging ◽

10.1177/016173460502700202 ◽

2005 ◽

Vol 27 (2) ◽

pp. 75-88 ◽

Cited By ~ 41

Author(s):

Mark L. Palmeri ◽

Kristin D. Frinkley ◽

Liang Zhai ◽

Marcia Gottfried ◽

Rex C. Bentley ◽

...

Keyword(s):

Radiation Treatment ◽

Acoustic Radiation ◽

Ex Vivo ◽

Radiation Force ◽

Acoustic Radiation Force ◽

High Intensity Focused Ultrasound ◽

Acoustic Radiation Force Impulse ◽

Gi Tract ◽

Small Bowel Tumors ◽

Arfi Imaging

The evaluation of lesions in the gastrointestinal (GI) tract using ultrasound can suffer from poor contrast between healthy and diseased tissue. Acoustic Radiation Force Impulse (ARFI) imaging provides information about the mechanical properties of tissue using brief, high-intensity, focused ultrasound to generate radiation force and ultrasonic correlation-based methods to track the resulting tissue displacement. Using conventional linear arrays, ARFI imaging has shown improved contrast over B-mode images when applied to solid masses in the breast and liver. The purpose of this work is to (1) investigate the potential for ARFI imaging to provide improvements over conventional B-mode imaging of GI lesions and (2) demonstrate that ARFI imaging can be performed with an endocavity probe. ARFI images of an adenocarcinoma of the gastroesophageal (GE) junction, status-post chemotherapy and radiation treatment, demonstrate better contrast between healthy and fibrotic/malignant tissue than standard B-mode images. ARFI images of healthy gastric, esophageal, and colonic tissue specimens differentiate normal anatomic tissue layers (i.e., mucosal, muscularis and adventitial layers), as confirmed by histologic evaluation. ARFI imaging of ex vivo colon and small bowel tumors portray interesting contrast and structure that are not as well defined in B-mode images. An endocavity probe created ARFI images to a depth of over 2 cm in tissue-mimicking phantoms, with maximum displacements of 4 μm. These findings support the clinical feasibility of endocavity ARFI imaging to guide diagnosis and staging of disease processes in the GI tract.

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Improved Acoustic Radiation Force Impulse Imaging Using Split-Focused Ultrasound Transducer With Phase Inversion Technique

IEEE Sensors Journal ◽

10.1109/jsen.2020.3021584 ◽

2021 ◽

Vol 21 (2) ◽

pp. 1395-1403

Author(s):

Eun Young Jeong ◽

Jin Ho Sung ◽

Jong Seob Jeong

Keyword(s):

Phase Inversion ◽

Focused Ultrasound ◽

Acoustic Radiation ◽

Radiation Force ◽

Acoustic Radiation Force ◽

Acoustic Radiation Force Impulse ◽

Ultrasound Transducer ◽

Inversion Technique ◽

Phase Inversion Technique

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Rationale Abklärung von Lebererkrankungen

Therapeutische Umschau ◽

10.1024/0040-5930/a000889 ◽

2017 ◽

Vol 74 (3) ◽

pp. 79-86

Author(s):

Leona von Köckritz ◽

Andrea De Gottardi

Keyword(s):

Acoustic Radiation ◽

Radiation Force ◽

Acoustic Radiation Force ◽

Acoustic Radiation Force Impulse ◽

Alkalische Phosphatase ◽

Gamma Glutamyltransferase ◽

Alpha 1 Antitrypsin

Zusammenfassung. Im klinischen Alltag werden häufig erhöhte Leberwerte beobachtet. In der Regel erfordern sie weitere Abklärungen bezüglich der möglichen Ätiologie und des Schweregrad einer akuten oder chronischen Lebererkrankung. Die Abklärung sollte dabei neben einer gezielten Anamnese und sorgfältigen klinischen Untersuchung, auch die Bestimmung von laborchemischen Markern für Cholestase und Leberfunktionsstörungen (wie Alkalische Phosphatase, gamma-Glutamyltransferase, Bilirubin, Albumin und Gerinnungsfaktoren) umfassen. Die Bestimmung weiterer Parameter wie Ferritin und Transferrinsättigung, Autoimmunantikörper, Virusserologien, alpha-1 Antitrypsin und Coerulolasmin können weitere Hinweise für die kausalen Zusammenhänge der Leberfunktionsstörung liefern. Bei Patienten mit Lebererkrankungen ist eine sonografische Beurteilung der Leber obligat. Ergänzend zur Sonografie werden heute weitere nicht-invasive Methoden wie Fibroscan, Acoustic Radiation Force Impulse Elastometrie und Magnet-Resonanz-Elastografie zur Beurteilung der Leberfibrose eingesetzt. In ausgewählten Fällen ist eine Leberbiopsie notwendig, um den Grad der Fibrose und die Ätiologie der Lebererkrankung zu eruieren. Mithilfe eines Fallbeispiels, diskutieren die Autoren im Folgenden die rationale Anwendung diagnostischer Tests und deren korrekte Interpretation und schlagen eine Orientierungshilfe zur rationalen Abklärung von Patienten mit Lebererkrankungen vor.

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