Department of Radiology, the Second Hospital of Zunhua City, Hebei, 064200;
Department of Radiology, People's Hospital of Zunhua City, Hebei, 064200;
Department of Radiology, the Third Hospital of Tanshan City, Hebei, 063000;
Department of Radiology, People's Hospital of Zunhua City, Hebei, 064200;
Department of Radiology, Maternity and Child Care Center of Tanshan City, 063000;