An X-ray cassette for computed radiography is provided, said cassette having a form of a hollow box comprising top and bottom, front and rear, and lateral sides, said top and bottom sides having width dimensions, between said lateral sides, and depth dimensions, between said front and rear sides, which are substantially greater than the dimensions of said front, rear and lateral sides, between said top and bottom sides, wherein said bottom side and said front, rear and lateral sides have a higher material stiffness than the top side and wherein said top side is a deformable carrier or support material, supporting a storage or stimulable phosphor sheet layer.