Modelling the Dynamics of Vacuum Aspiration

Two mathematical models of vacuum aspiration, being a method widely used in various branches of medicine, are considered. In particular, vacuum aspiration is an effective method of prostatitis therapy. The purpose of vacuum aspiration in this urological procedure is to destroy the plug, which clogs up the ill acinus. We analyze plausible physical mechanisms of purification of prostatic acini and ducts on the basis of two different models. A mechanical model is offered to describe the process of plug destruction during vacuum aspiration procedure. The majority of medical practitioners believe that the plug is extracted as a whole during such procedure. However, our theoretical research demonstrates that the sucking of a plug as a whole, previously viewed as the most likely mechanism, is not consistent with the experimental data. The second model implies non-uniform structure of the plug. The problem considered in the framework of the latter assumption belongs to self-organized criticality type of problems. This approach reveals the plug destruction dynamics which corresponds to essential clinical data. Key-Words: vacuum aspiration, prostatitis, physical models, lattice of springs, self-organized criticality