A teletherapy treatment arrangement constituted of: a control unit a 3 dimensional imager having an effective patient plane 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 the 3 dimensional imager and a patient positioner arranged to secure a target tissue in a fixed relationship to the patient positioner, the control unit arranged to: input a planned treatment position of the patient target tissue in the event that the planned treatment position is consonant with the effective patient plane of the 3 dimensional imager, obtain position information of the target tissue from the 3 dimensional imager, and in the event that the planned treatment position is not consonant with the effective patient plane of the 3 dimensional imager, obtain position information of the target tissue from the at least one 2 dimensional imager.
