Simulation-Based Cryosurgery Training

Abstract

A proof-of-concept for an advanced-level computerized training tool for cryosurgery is demonstrated, based on three-dimensional cryosurgery simulations and a variable insertion-depth strategy for cryoprobes. The objective for system development is twofold: to identify a cryoprobe layout in order to best-match a planning isotherm with the target region shape, and to verify that cryoprobe placement does not violate accepted geometric constraints. System validation has been performed by collecting training data from 17 surgical residents, having no prior experience or advanced knowledge of cryosurgery. This advanced-level study includes an improved training-session design, in order to enhance knowledge dissemination and elevate participant motivation to excel. In terms of match between a planning isotherm and the target region shape, results of this demonstrate trainee performance improvement from 4.4% in a pretest to 44.4% in a posttest over a course of 50 minutes of training. In terms of combined performance, including the above geometrical match and constraints on cryoprobe placement, this study demonstrates trainee performance improvement from 2.2% in the pretest to 31.1% in the posttest. Given the relatively short training session and the lack of prior knowledge, these improvements are significant and encouraging. These results are of particular significance, as they have been obtained from a surgical resident population, which are exposed to the typical stress and constraints in advanced surgical education.

GPU-Based Simulation of Ultrasound Imaging Artifacts for Cryosurgery Training

“…A six-step scheme is proposed to generate the imaging artifacts, and GPU-based real-time implementation strategies are discussed. The proposed implementation relies on a previously developed scheme for GPU-based bioheat transfer simulations of cryosurgery [26,27,30]. The temperature field generated by bioheat transfer simulations is used as an input for ultrasound artifacts calculations.…”

“…Once the 3D shape of the prostate was reconstructed, an array of cryoprobes was virtually placed at a single insertion depth, using a computer-generated optimized layout based on the bubble-packing method [18]. Next, a bioheat transfer simulation was executed, using a GPU-based embodiment [30] of an efficient numerical scheme for the bioheat transfer process [21]. This combination of a numerical method and a coding framework is characterized by a typical runtime of 2 seconds for a complete procedure [30].…”

“…Next, a bioheat transfer simulation was executed, using a GPU-based embodiment [30] of an efficient numerical scheme for the bioheat transfer process [21]. This combination of a numerical method and a coding framework is characterized by a typical runtime of 2 seconds for a complete procedure [30]. …”

Defeating Cancers’ Adaptive Defensive Strategies Using Thermal Therapies: Examining Cancer’s Therapeutic Resistance, Ablative, and Computational Modeling Strategies as a means for Improving Therapeutic Outcome

“…Recently, efforts by Rabin and coworkers have led to the development of the first software prototype for cryosurgery tutoring. 161 – 163 , 180 This prototype lists geometrical constraints on cryoprobe placement, displays a rendered shape of the prostate, simulates cryoprobe insertion, enables distance measurements as would be facilitated by US imaging, simulates the corresponding thermal history, 178 and evaluates the mismatch between the target region shape and a pre-selected planning isotherm in terms of defect values. The quality of a trainee planning is measured in comparison to a computer-generated plan, created for each case study using the bubble-packing algorithm.…”

“…When comparing different cryoprobe layouts, the one that results in the minimum overall defect may be considered superior. Either way, the defect region concept can serve as the basis for computer-generated cryotherapy planning, [157][158][159][160] training, [161][162][163] and analysis of past procedures. Conceptually, the defect region concept is translational from cryotherapy to any thermal ablation application, by substituting the lethal temperature with the thermal dose for planning.…”