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Thermally induced apoptosis for tumors depends mainly on the intrinsic characteristics of biological tissues as well as treatment temperature profile during magnetic hyperthermia. Further, treatment temperature distribution inside tumor depends on the injection behavior of irregular tumors, such as the injection dose and the injection location of nanofluids. In order to improve the treatment effect, the simulated annealing algorithm is adopted in this work to optimize the nanofluid injection behavior, and the improved Arrhenius model is used to evaluate the malignant ablations for three typical malignant tumor cell models. In addition, both the injection behavior optimization and the mass diffusion of nanofluid are both taken into consideration in order to improve the treatment effect. The simulation results demonstrate that the injection behavior can be optimized effectively by the proposed optimization method before therapy, the result of which can also conduce to improving the thermal apoptosis possibility for proposed typical malignant cells. Furthermore, an effective approach is also employed by considering longer diffusion duration and correct power dissipation at the same time. The results show that a better result can then be obtained than those in other cases when the power dissipation of MNPs is set to be Q MNP = 5.4 × 107 W·m3 and the diffusion time is 16 h.

Thermal damage of malignant tissue is generally determined not only by the characteristics of bio-tissues and nanoparticles but also the nanofluid concentration distributions due to different injection methods during magnetic hyperthermia. The latter has more advantages in improving the therapeutic effect with respect to the former since it is a determining factor for the uniformity of nanofluid concentration distribution inside the tumor region. This study investigates the effect of bio-tissue deformation due to intratumoral injection on the thermal damage behavior and treatment temperature distribution during magnetic hyperthermia, in which both the bio-tissue deformation due to nanofluid injection and the mass diffusion after injection behavior are taken into consideration. The nanofluid flow behavior is illustrated by two different theoretical models in this study, which are Navier–Stokes equation inside syringe needle and modified Darcy’s law inside bio-tissue. The diffusion behavior after nanofluid injection is expressed by a modified convection–diffusion equation. A proposed three-dimensional liver model based on the angiographic data is set to be the research object in this study, in which all bio-tissues are assumed to be deformable porous media. Simulation results demonstrate that the injection point for syringe needle can generally achieve the maximum value in the tissue pressure, deformation degree, and interstitial flow velocity during the injection process, all of which then drop sharply with the distance away from the injection center. In addition to the bio-tissue deformation due to injection behavior, the treatment temperature is also highly relevant to determine both the diffusion duration and blood perfusion rate due to the thermal damage during the therapy.

This article introduces a new calibration method for machine vision measurement system--calibration method using concentric circles planar template. This method not only considering lens distortion and random errors introduced by the process of calibration, but also overcome limitation of strict demands for the standard parts’ position and complexity in stereovision computation, it also capable of conduct calibration to the whole scene depth space, effectively improve the efficiency of calibration with its simple and high precision mean. A relatively high precision can be achieved by applying this new method to diameter measurement of cable line, which is suitable to conduct on-field industrial dimension measurement calibration.