To address the need for an apparatus and method for handoff from a cellular wireless network to a non-cellular wireless network, the present application describes an access gateway and a dual mode mobile station that enable such handoffs. One area defined by a user as a target on an image slice can be found in a corresponding area on a nearby neighboring image slice by using a deformation field generated with deformable image registration procedure between these two image slices. Additionally, the method includes receiving a retransmission of the at least a portion of the incomplete segment. The CSI is transmitted back to the transmitter unit.