A medical device comprising a wall, a coating of SiOx, and a piezochromic material is disclosed. The piezochromic material is associated with the wall, and changes its appearance when the wall is exposed to mechanical stress exceeding a threshold intensity. Also disclosed is a method of interrogating a closed medical device for processing damage, comprising at least the acts of providing a closed medical device and inspecting the medical device. The medical device is inspected from the exterior for a change in the appearance of at least some of its piezochromic material that is characteristic of exposure of the wall to mechanical stress exceeding a threshold intensity greater than zero. Optionally in any embodiment inspecting is carried out using a spectrophotometer to determine the change in the color of at least some of its piezochromic material.
