Optimization of intravascular brachytherapy treatment planning in peripheral arteries

Abstract

Abstract. This work deals with the treatment planning optimization for intravascular brachytherapy (IVB) in peripheral arteries. The objective is both to quantitatively study the validity of different hypotheses required for a reliable application of the treatment with current techniques, and to contribute to the definition and the specification of a new optimized procedure taking into account the actual patient's vessel geometry. The detection of vascular luminal surface was performed by an image analysis process, i.e. virtual active navigation, applied to standard CT data. Dose distribution was calculated according to the formalism proposed and recommended by the AAPM in TG43 and TG60. A method combining simulated annealing and BFGS algorithms was applied to optimize the parameters associated with the dwell points such as their number, positions, and dwell times. Dose-surface histogram (DSH) was used to evaluate the dose distribution results. Four levels of accuracy in target surface description were tested. The application of this optimization method to four different CT data sets including patient data, phantom and animal models showed that the treatment plan can be improved when the actual vessel geometry has been taken into account.

Analysis of rotation angles and motions of the flexible mechanisms in bifurcated blood vessels

“…Three-dimensional geometry of blood vessels can be achieved with computed tomography (CT) technology. 23 Bifurcated blood vessels are the most common types of blood vessels in human, the shape of which is like a branched tree. Figure 2(a) is the vessel of the human thigh, a part of it is shown in Figure 2(b), and the mathematical model is shown in Figure 2(c).…”