DocumentCode :
953507
Title :
A Soft-Computing Methodology for Noninvasive Time-Spatial Temperature Estimation
Author :
Teixeira, César A. ; Ruano, Maria Graça ; Ruano, António E. ; Pereira, Wagner C A
Author_Institution :
Univ. of Algarve, Faro
Volume :
55
Issue :
2
fYear :
2008
Firstpage :
572
Lastpage :
580
Abstract :
The safe and effective application of thermal therapies is restricted due to lack of reliable noninvasive temperature estimators. In this paper, the temporal echo-shifts of backscattered ultrasound signals, collected from a gel-based phantom, were tracked and assigned with the past temperature values as radial basis functions neural networks input information. The phantom was heated using a piston-like therapeutic ultrasound transducer. The neural models were assigned to estimate the temperature at different intensities and points arranged across the therapeutic transducer radial line (60 mm apart from the transducer face). Model inputs, as well as the number of neurons were selected using the multiobjective genetic algorithm (MOGA). The best attained models present, in average, a maximum absolute error less than 0.5 C, which is pointed as the borderline between a reliable and an unreliable estimator in hyperthermia/diathermia. In order to test the spatial generalization capacity, the best models were tested using spatial points not yet assessed, and some of them presented a maximum absolute error inferior to 0.5 C, being ldquoelectedrdquo as the best models. It should be also stressed that these best models present implementational low-complexity, as desired for real-time applications.
Keywords :
backscatter; biomedical transducers; biomedical ultrasonics; genetic algorithms; hyperthermia; medical computing; patient treatment; phantoms; radial basis function networks; temperature measurement; ultrasonic transducers; backscattered ultrasound signals; biomedical acoustics; diathermia; feedforward neural networks; gel-based phantom; hyperthermia; multiobjective genetic algorithm; neural models; noninvasive time-spatial temperature estimation; phantom; piston-like therapeutic ultrasound transducer; radial basis functions neural networks; soft-computing methodology; temporal echo-shift; thermal therapies; Genetic algorithms; Hyperthermia; Imaging phantoms; Medical treatment; Neurons; Radial basis function networks; Temperature; Testing; Ultrasonic imaging; Ultrasonic transducers; Biomedical acoustics; Temperature measurement; biomedical acoustics; feedforward neural networks; genetic algorithms; temperature measurement; Algorithms; Humans; Image Interpretation, Computer-Assisted; Reproducibility of Results; Sensitivity and Specificity; Thermography; Ultrasonic Therapy; Ultrasonography;
fLanguage :
English
Journal_Title :
Biomedical Engineering, IEEE Transactions on
Publisher :
ieee
ISSN :
0018-9294
Type :
jour
DOI :
10.1109/TBME.2007.901029
Filename :
4360063
Link To Document :
بازگشت