1. An endoscopic system for determining a property of human tissue, comprising: a probe comprising a portion delivering a stream of gas that applies a pressure to a surface of the human tissue and deforms an area of the surface; a spatial phase imaging sensor that uses spatial phase image information and that measures three-dimensional surface topographies of the area of the surface of the human tissue including three-dimensional surface topographies of the deformation of the area of the surface in response to the application of the pressure by the probe; a processing system that receives the three-dimensional surface topographies from the spatial phase imaging sensor and determines a property of the human tissue from the three-dimensional surface topographies; and a display system that displays information relating to a property of the human tissue.