Objective. Surgery is one of the riskiest and most important medical acts that is performed today. Understanding the ways in which surgeries are similar or different from each other is of major interest. Desires to improve patient outcomes and surgeon training, and to reduce the costs of surgery, all motivate a better understanding of surgical practices. To facilitate this, surgeons have started recording the activities that are performed during surgery. New methods have to be developed to be able to make the most of this extremely rich and complex data. The objective of this work is to enable the simultaneous comparison of a set of surgeries, in order to be able to extract high-level information about surgical practices.
Material and Method.We introduce Non-Linear Temporal Scaling (NLTS): a method to realign a set of surgeries along their intrinsic timeline. Experiments are carried out on a set of lumbar disc neurosurgeries. We assess our method both on a highly standardised phase of the surgery (closure) and on the whole surgery.Results. Experiments show that NLTS makes it possible to consistently derive standards of surgical practice and to understand differences between groups of surgeries. We take the training of * Corresponding author -ENSISA -Universite de Haute Alsace, 12 rue des freres Lumiere, 68093 Mulhouse, France, Tel.:+33 3 8933 6963, Fax.:+33 3 8942 3282Email addresses: germain.forestier@uha.fr (Germain Forestier), francois.petitjean@monash.edu (François Petitjean), laurent.riffaud@chu-rennes.fr (Laurent Riffaud), pierre.jannin@univ-rennes1.fr (Pierre Jannin)
Preprint submitted to Artificial Intelligence in MedicineSeptember 16, 2013 surgeons as the common theme for the evaluation of the results and highlight, for example, the main differences between the practices of junior and senior surgeons in the removal of a lumbar disc herniation.Conclusion. NLTS realigns a set of sequences along their intrinsic timeline, which makes it possible to extract standards of surgical practices.Supplementary material. The computer code implementing the proposed methods.