PURPOSE: A method and an apparatus for reconstructing an image for performing the parallel-treatment in the high definition positron emission tomography are provided to convert the sinogram format so that the sinogram format is suitable to the parallel-treatment in a forward projection and a back projection during the image reconstruction based on ordered subset expectation maximization (OSEM), thereby facilitating the computing optimized to the parallel-treatment. CONSTITUTION: A method for reconstructing an image for performing the parallel-treatment is as follows. The line-of-response which is detected from a detector is converted into a sinogram format which has a cone beam shape by responding to the radiation with which a measurement target body is irradiated (810). The back projection is performed based on the converted lines-of-response (830). The image is reconstructed by using the performance result of the back projection (850). [Reference numerals] (810) Convert the line-of-response (LOR) into a sinogram format with the shape of a cone beam； (830) Perform back projection； (850) Reconstruct the image； (AA) Start； (BB) End본 발명은 영상 재구성에 관한 것으로서, 보다 구체적으로는 고해상도 양전자 방출 단층 촬영에서 병렬 처리를 위해 영상을 재구성하는 방법 및 장치에 관한 것이다. 일 실시예에 따르면, 영상을 재구성하는 방법은 측정 대상체에 조사된 방사선에 응답하여 검출기들로부터 검출된 반응선((Line-Of-Response； LOR)들을 콘 빔(cone beam) 형태의 여현 곡선 포맷(sinogram format)으로 변환하는 단계； 상기 변환된 반응선들을 기초로 역투영(back projection)를 수행하는 단계； 및 상기 역투영의 수행 결과를 이용하여 영상을 재구성하는 단계를 포함한다.
