1. A teletherapy treatment arrangement comprising: a control unit; a 3 dimensional imager in communication with said control unit and responsive thereto, said 3 dimensional imager having an effective patient plane and arranged to image a patient target tissue; at least one 2 dimensional imager in communication with said control unit and responsive thereto, said at least one 2 dimensional imager arranged to provide a pair of 2 dimensional images along planes generally orthogonal to the effective patient plane of said 3 dimensional imager; and a patient positioner responsive to said control unit, said patient positioner arranged to secure a patient target tissue in a fixed spatial relationship to said patient positioner, said control unit arranged to: input a planned treatment position of the patient target tissue; in the event that said input planned treatment position is consonant with the effective patient plane of said 3 dimensional imager, obtain position information of the patient target tissue from said 3 dimensional imager; in the event that said input planned treatment position is not consonant with the effective patient plane of said 3 dimensional imager, obtain position information of the patient target tissue from said at least one 2 dimensional imager; and control said patient positioner so as to position the target tissue in relation to an irradiation source responsive to said obtained position information.