The Feasibility of Conformal Thermal Therapy with Transurethral Ultrasound Heating Applicators and MR Temperature Feedback

Journal Article · Mon May 08 00:00:00 EDT 2006 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.2205455· OSTI ID:20800255

Choy, Vanessa; Tang, Kee; Chopra, Rajiv ^[1]; Wachsmuth, Jeff ^[2]; Bronskill, Michael ^[1]

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1. Sunnybrook and Women's College Health Sciences Centre, Toronto, Ontario (Canada)
2. Department of Medical Biophysics, University of Toronto, Toronto, Ontario (Canada)

Transurethral thermal therapy offers a minimally invasive alternative for the treatment of prostate diseases including benign prostate hyperplasia (BPH) and prostate cancer. Accurate heating of a targeted region of the gland can be achieved through the use of a rotating directional heating source incorporating planar ultrasound transducers, and the implementation of active temperature feedback along the beam direction during heating provided by magnetic resonance (MR) thermometry. The performance of this control method with practical spatial, temporal, and temperature resolution (such as angular alignment, spatial resolution, update rate for temperature feedback (imaging time), and the presence of noise) for thermal feedback using a clinical 1.5 T MR scanner was investigated in simulations. As expected, the control algorithm was most sensitive to the presence of noise, with noticeable degradation in its performance above {+-}2 deg. C of temperature uncertainty. With respect to temporal resolution, acceptable performance was achieved at update rates of 5s or faster. The control algorithm was relatively insensitive to reduced spatial resolution due to the broad nature of the heating pattern produced by the heating applicator, this provides an opportunity to improve signal-to-noise ratio (SNR). The overall simulation results confirm that existing clinical 1.5T MR imagers are capable of providing adequate temperature feedback for transurethral thermal therapy without special pulse sequences or enhanced imaging hardware.

• OSTI ID: 20800255
• Journal Information: AIP Conference Proceedings, Vol. 829, Issue 1; Conference: 5. international symposium on therapeutic ultrasound, Boston, MA (United States), 27-29 Oct 2005; Other Information: DOI: 10.1063/1.2205455; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
61 RADIATION PROTECTION AND DOSIMETRY
ALGORITHMS
COMPUTERIZED SIMULATION
FEEDBACK
HEATING
NEOPLASMS
NMR IMAGING
NOISE
NUCLEAR MAGNETIC RESONANCE
PERFORMANCE
PROSTATE
PULSES
RADIOTHERAPY
SIGNAL-TO-NOISE RATIO
SPATIAL RESOLUTION
TEMPERATURE CONTROL
TRANSDUCERS
ULTRASONOGRAPHY