A Preliminary Numerical Thermal Analysis of an Endometrial Ablation Procedure Based on Foley’s Catheter

Resumo

Dysfunctional uterine bleeding (DUB) is an ailment affecting a substantial number of women during a significant part of their reproductive years. This condition usually leads to discomfort, mild or severe pain, or, in some extreme cases, anemia. It may be caused by diverse factors such as hormonal issues, structural abnormalities, or even cancer in a womans reproductive tract. A typical DUB treatment requires a pharmacological approach through the prescription of drugs. Nonetheless, some patients require a more involved treatment calling for surgical procedures. In order to avoid hysterectomy, which is the complete removal of the uterus, the medical community has devised, over the years, alternative surgical schemes to handle DUB issues. One such treatment is the endometrial ablation technique where the inner lining of the uterus is subjected to a controlled destruction by using a hot, approximately constant-temperature fluid inside a balloon, which is placed in contact with the uterine wall of the patient. As a means to avoid the high costs associated with such devices, the medical community has proposed a similar treatment in which the fluid inside the balloon is no longer held at a high constant temperature but rather diminishes as the treatment progresses. The main purpose of this contribution is to critically assess the effectiveness of this second, low-cost endometrial ablation treatment. Consequently, a mathematical model is devised in which Pennes bioheat equation is employed to predict the transient temperature field of the uterine wall together with an energy balance that yields the temperature of the saline solution inside the thermal balloon, throughout the duration of the treatment. These equations aresolved by utilizing the finite volume method and the numerical predictions are verified by comparing the present results with similar cases from the literature. Once the verification phase is authenticated, the uterine wall and fluid balloon transient temperature fields are obtained for typical situations reported in the medical literature. On general grounds, the simulations indicate that the extent of the affected tissue is strongly dependent on the volume,on the type of fluid inside the thermal balloon, and on the magnitude of the perfusion of the uterus. Moreover, it was found that the proposed low-cost treatment can indeed be a successful alternative to the standard endometrial ablation process under some viable circumstances that are described in the contribution.