| Autor: |
J. Vincenot, D. Melodelima, F. Chavrier, J. Y. Chapelon, Yoichiro Matsumoto, Lawrence A. Crum, Gail Reinette ter Haar |
| Rok vydání: |
2011 |
| Předmět: |
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| Zdroj: |
AIP Conference Proceedings. |
| ISSN: |
0094-243X |
| Popis: |
Spherical transducers used for HIFU therapy produce small single lesions that are ellipsoidal in shape. The placement of these lesions side by side requires precision if an entire tumor is to be ablated reliably. This can be difficult to produce in moving organs like the liver. It has been shown that a toroidal transducer makes it possible to significantly increase the focal zone. A HIFU device has been developed using this principle to treat liver metastases during an open procedure. The toroidal transducer is composed of 256 elements. Metastases suitable for such a local therapy are typically 2 cm in diameter. A typical ablation produced in vitro in 40 seconds has an average diameter of 14.1 mm and an average depth of 28.5 mm. Despite this progress, it remains necessary to juxtapose these single lesions to treat tumors with safety margins. The aim of this project is to use electronic beam steering in order to avoid the need to juxtapose single ablations. In vitro tests were conducted to validate new treatment parameters determined using software developed in the laboratory. It was shown that, using electronic focusing, similar treatment can be achieved in half the time (20 s). The average diameter and depth of these ablations were 12.9 mm and 31.1 mm respectively. In addition, it was possible to double the coagulated volume while keeping the same duration of treatment. In this case the average ablated dimensions obtained in 40 seconds were 25.8 mm in diameter, and 42.5 mm in length. Finally, larger ablations with an average diameter and length of 40.0 mm and 54.4 mm respectively have been obtained in 130 seconds. In conclusion, these results indicate that the treatment of a metastasis in the liver with safety margins is conceivable using a single exposure with no need to juxtapose single lesions. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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