A method of selectively removing folds in a medical image is provided. With this method, a medical image is deformed to straighten and flatten folds but not polyps, thus allowing polyps to be identified. In a first step, a 3-dimensional deformable model of the medical image is constructed. This model is set to have a high Young's modulus and a low Poisson's ratio. In a preferred embodiment, the model is a continuum surface model, preferably a quasistatic continuum finite element model. Once the model has been constructed, it is deformed such that folds are removed but polyps remain, allowing polyps to be identified.