Method for effecting local increases in temperature inside materials, particularly body tissue

US7645235B2 · kind B2 · utility

Assignee

• RICHARD WOLF GMBH · DE

Inventors

• Siegfried Ginter · Blankenloch, DE
• Marko Liebler · Bretten, DE
• Thomas Dreyer · Achim, DE
• Rainer Riedlinger · Karlsruhe, DE

Key dates

• Filing date: Jul 29, 2003
• Grant date: Jan 12, 2010
• Expiry date: Jun 15, 2024

Classification

• Technology area (CPC A): Human Necessities
• CPC primary: A61N7/02
• WIPO field: Medical technology
• WIPO sector: Instruments

Abstract

Local tissue areas should be thermally destroyed when using ultrasound thermotherapy. Traditionally, mono-frequency continuous wave ultrasound signals are used to this end. These lead to a non-optimal distribution of heat or to a non-optimal localization of the heating inside the tissue. In practice, the following dosage problem arises: the prevention of unwanted tissue damage in the tissue located in front of the target area while simultaneously having a sufficiently high damaging effect in the target area. The aim of the invention is to optimize the distribution of heat or to increase the localization of the heating. To these ends, modified transmitted signals (e.g. multi-frequency signals) are used that are adapted to a specific utilization of the non-linear ultrasound propagation and attenuation properties inside the tissue. This enables, while limited to the target area, a non-linear heating yield caused by non-linear ultrasound effects to be achieved that drastically improves the localization of the heating. Due to this optimization, the problem of dosage is substantially eased, and it is possible to thermally destroy even deep-lying tumors without unwanted burning of the tis…