The role of exposure time in computerized training of prostate cryosurgery: performance comparison of surgical residents with engineering students

  • Purva Joshi
  • Anjali Sehrawat
  • Yoed Rabin
Original Article



This study aims at the evaluation of a prototype of a computerized trainer for cryosurgery—the controlled destruction of cancer tumors by freezing. The hypothesis in this study is that computer-based cryosurgery training for an optimal cryoprobe layout is essentially a matter of exposure time, rather than trainee background or the specific computer-generated planning target. Key geometric features under considerations are associated with spatial limitations on cryoprobes placement and the match between the resulted thermal field and the unique anatomy of the prostate.


All experiments in this study were performed on the cryosurgery trainer—a prototype platform for computerized cryosurgery training, which has been presented previously. Among its key features, the cryosurgery trainer displays the prostate shape and its contours and provides a distance measurement tool on demand, in order to address spatial constraints during ultrasound imaging guidance. Another unique feature of the cryosurgery trainer is an output movie, displaying the simulated thermal field at the end of the cryoprocedure.


The current study was performed on graduate engineering students having no formal background in medicine, and the results were benchmarked against data obtained on surgical residents having no experience with cryosurgery. Despite fundamental differences in background and experience, neither group displayed superior performance when it comes to cryoprobe layout planning.


This study demonstrates that computer-based training of an optimal cryoprobe layout is feasible. This study demonstrates that the training quality is essentially related to the training exposure time, rather than to a specific planning strategy from those investigated.


Cryosurgery Prostate Simulation Planning Training Evaluation 



This study has been supported in part by Grant Number R01CA134261 to from the National Cancer Institute (USA) to Yoed Rabin. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Cancer Institute or the National Institutes of Health.

Compliance with ethical standards

Conflict of interest

The authors declare no conflict of interest. Yoed Rabin is a board member of the American College of Cryosurgery and a member of the Board of Governors of the International Society for Cryosurgery.


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Copyright information

© CARS 2018

Authors and Affiliations

  1. 1.Department of Mechanical EngineeringCarnegie Mellon UniversityPittsburghUSA

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