title: Computerized planning for multiprobe cryosurgery using a force-field analogy.
abstract: Cryosurgery is the destruction of undesired biological tissues by freezing. For internal organs, multiple cryoprobes are inserted into the tissue with the goal of maximizing cryoinjury within a predefined target region, while minimizing cryoinjury to the surrounding tissues. The objective of this study is to develop a computerized planning tool to determine the best locations to insert the cryoprobes, based on bioheat transfer simulations. This tool is general and suitable for all available cooling techniques and hardware. The planning procedure employs a novel iterative optimization technique based on a force-field analogy. In each iteration, a single transient bioheat transfer simulation of the cryoprocedure is computed. At the end of the simulation, regions of tissue that would have undesired temperatures apply "forces" to the cryoprobes directly moving them to better locations. This method is more efficient than traditional numerical optimization techniques, because it requires significantly fewer bioheat transfer simulations for each iteration of planning. For demonstration purposes, 2D examples on cross sections typical of prostate cryosurgery are given.
authors.affiliation: Department of Mechanical Engineering, Carnegie Mellon University, 15213 Pittsburgh, PA, USA.
authors.forename: David C
authors.initials: DC
authors.lastname: Lung
authors.forename: Thomas F
authors.initials: TF
authors.lastname: Stahovich
authors.forename: Yoed
authors.initials: Y
authors.lastname: Rabin
mesh_terms: D000465:Algorithms; D003198:Computer Simulation; D003452:Cryosurgery / Q000379:methods*; D006801:Humans; D008297:Male; D008954:Models, Biological; D009716:Numerical Analysis, Computer-Assisted; D011300:Preoperative Care / Q000379:methods; D011467:Prostate / Q000503:physiopathology / Q000601:surgery; D011471:Prostatic Neoplasms / Q000503:physiopathology* / Q000601:surgery*; D013314:Stress, Mechanical; D025321:Surgery, Computer-Assisted / Q000379:methods*