A system which uses two remote cameras to obtain surface contours for
radiotherapy patients is described. Two variants are presented: one wh
ich requires couch movement to obtain multiple outlines, and one utili
zing a special illumination method to achieve multiple outlines from o
ne image per camera. In addition, a technique is discussed in which th
e grey-scale information from the skin surface (e.g., skin marks place
d by the radiotherapist) may be utilized in displaying three-dimension
al surface information. The system may also be used to monitor patient
position in real time during each treatment.