This thesis presents ExtrusionCutter - a novel 3D visualization tool that enables users to create complex, context-preserving cutaways of anatomical surface meshes. To accomplish this, a "paint-roller" interaction metaphor has been developed that allows users to extrude an editable cutting mesh along the natural geometry of an occluding surface. This virtual analogy of a familiar real-world action not only facilitates the removal of occluding surfaces, but also creates a user-defined region parameterization which makes it possible to also generate an effective contextual outline view of the removed material. This thesis will demonstrate how the paint roller interaction metaphor has been implemented to facilitate the creation of multiple editable cutaway types on 3D anatomical surface meshes. Additionally, it will show that the resulting cutaway views are capable of exposing occluded parts while still maintaining their context in the visualization.