ABSTRACT
A method of medical image segmentation based on support vector machine (SVM) for density estimation is presented. We used this estimator to construct a prior model of the image intensity and curvature profile of the structure from training images. When segmenting a novel image similar to the training images, the technique of narrow level set method is used. The higher dimensional surface evolution metric is defined by the prior model instead of by energy minimization function. This method offers several advantages. First, SVM for density estimation is consistent and its solution is sparse. Second, compared to the traditional level set methods, this method incorporates shape information on the object to be segmented into the segmentation process. Segmentation results are demonstrated on synthetic images, MR images and ultrasonic images.
Subject(s)
Humans , Image Interpretation, Computer-Assisted , Methods , Magnetic Resonance ImagingABSTRACT
<p><b>OBJECTIVE</b>To explore the influence of chemosensitivity of Tca8113 cells by modified MTT assay after the animal model of Tca8113 were treated by the ultrasound hyperthermia.</p><p><b>METHODS</b>The MTT assay of the BALB/C nu/nu mice model of Tca8113 cells treated by the ultrasound hyperthermia in vivo was performed.</p><p><b>RESULTS</b>The chemosensitivity to the 9 kinds of drugs demonstrated no significant differences between the Tca8113 cells in the control group, the 39 degrees C-treated group and the groups treated from 41 degrees C to 44 degrees C. But significant differences between the 40 degrees C-treated group and the 41 degrees C or 42 degrees C-treated group existed. In the heating-time grades test, there were no significant differences in the chemosensitivity to the 9 kinds of drugs between these three pairs of group (the control group and the 15 min-treated group, the 30 min-treated and the 45 min-treated group, the 60 min-treated and the 75 min-treated group). But there were significant differences between the 30 min-treated or the 45 min-treated group and the 60 min-treated or the 75 min-treated group.</p><p><b>CONCLUSION</b>Ultrasound hyperthermia performed in 42 degrees C for 30-45 min can improve the chemosensitivity of Tca8113 cells to some drugs significantly, which confirms the rationality of synchronous combination of hyperthermia and chemotherapy in the chemosensitivity point of view for the first time.</p>
Subject(s)
Animals , Mice , Antineoplastic Agents , Heating , Hyperthermia, Induced , Mice, Inbred BALB C , Mice, Nude , Mouth NeoplasmsABSTRACT
Development of an ultrasonic hyperthermia instrument's software based on ARM32 microprocessor is here introduced. The system integrates the embedded SOC system, memory system, PWM system, A/D system, JTAG debug system, UART communication system, I/O system and GUI system (include LCD, keyboard) in one PCB board. It effectively completes the control and constance of temperature through the improved PID algorithm, and the instrument miniaturization. Experiments have proved that the system accords with the design requirements.
Subject(s)
Humans , Algorithms , Hyperthermia, Induced , Signal Processing, Computer-Assisted , Software Design , Temperature , UltrasonicsABSTRACT
Focused Ultrasound Surgery (FUS) is a promising minimally invasive technique in tissue ablation. Because of the high intensity at the ultrasound focus, a precise 3D-localization system is required to determine the site of the treating target in order to increase the efficiency and security of FUS. This paper represents a three dimensional ultrasound (3D US) localization system developed and its workflow. The system is mainly composed of imaging and image processing system, movement device and its controlling circuits, and position feedback device. The system has a maximum scan range of +/- 30 degrees with a resolution of 8 levels from 0.54' to 0.36 degrees. For a spherical shape like target, in theory, the maximum diameter is 160 mm the system can treat. The system can be used to localize precisely the treatment targets with general sizes in the suitable parts of the body in FUS.
Subject(s)
Humans , Algorithms , Electronic Data Processing , Computer Simulation , Equipment Design , Image Processing, Computer-Assisted , Methods , Imaging, Three-Dimensional , Microcomputers , Surgery, Computer-Assisted , Methods , Ultrasonic Therapy , MethodsABSTRACT
The development of a RF ablation therapeutic instrument based on improved PID algorithm is introduced here. It is based on the theory of radio frequency local destruction. By adopting the improved PID temperature control algorithm, the problem of the temperature control precision reduction due to tumor tissue characteristic changing by heating has been solved, thus ensuring homogeneous and smooth radio frequency heating to tumor foci. Experiments demonstrate that the new algorithm has strong adaptability and anti-disturbance capability, the equipment works stably and reliably, and can control therapeutic temperature precisely (+/- 2 degrees C), which indicates a good clinical application value.
Subject(s)
Humans , Algorithms , Calorimetry , Methods , Catheter Ablation , Methods , Electrodes , Equipment Design , Hyperthermia, Induced , Methods , Information Storage and Retrieval , Neoplasms , Therapeutics , Software , TemperatureABSTRACT
This paper describes the development of the combined tumor therapeutic equipment based on the theory of 1 + 1 = 3 or 1 + 1 > 3 tumor combined treatment synergism. It has become a promising and valuable method dealing with cancer tumors for its good adaptability, better effectiveness and convenience. The therapeutic equipment is combined with PC and MS windows operation system, and adopts intellectual temperature control device, which realizes homogeneous and smooth heating to intracavity tumor focus and automatic processing and statistical management of all case data. The equipment works stably and is of great value in clinical applications.