Dual-mode IVUS catheter for intracranial image-guided hyperthermia: feasibility study.
Journal Article (Journal Article)
In this study, we investigated the feasibility of modifying 3-Fr IVUS catheters in several designs to potentially achieve minimally-invasive, endovascular access for image-guided ultrasound hyperthermia treatment of tumors in the brain. Using a plane wave approximation, target frequencies of 8.7 and 3.5 MHz were considered optimal for heating at depths (tumor sizes) of 1 and 2.5 cm, respectively. First, a 3.5-Fr IVUS catheter with a 0.7-mm diameter transducer (30 MHz nominal frequency) was driven at 8.6 MHz. Second, for a low-frequency design, a 220-μm-thick, 0.35 x 0.35-mm PZT-4 transducer--driven at width-mode resonance of 3.85 MHz--replaced a 40-MHz element in a 3.5-Fr coronary imaging catheter. Third, a 5 x 0.5-mm PZT-4 transducer was evaluated as the largest aperture geometry possible for a flexible 3-Fr IVUS catheter. Beam plots and on-axis heating profiles were simulated for each aperture, and test transducers were fabricated. The electrical impedance, impulse response, frequency response, maximum intensity, and mechanical index were measured to assess performance. For the 5 x 0.5-mm transducer, this testing also included mechanically scanning and reconstructing an image of a 2.5-cm-diameter cyst phantom as a preliminary measure of imaging potential.
Full Text
Duke Authors
Cited Authors
- Herickhoff, CD; Grant, GA; Britz, GW; Smith, SW
Published Date
- November 2010
Published In
Volume / Issue
- 57 / 11
Start / End Page
- 2572 - 2584
PubMed ID
- 21041144
Pubmed Central ID
- PMC3018697
Electronic International Standard Serial Number (EISSN)
- 1525-8955
Digital Object Identifier (DOI)
- 10.1109/TUFFC.2010.1723
Language
- eng
Conference Location
- United States