Although the sample in this retrospective study was small (12 abused infants identified from 1999 to 2004), the findings indicate that CT is better than CXR in visualizing rib fractures in abused infants. A total of 131 rib fractures were visualized by CT, but only 79 were seen by CXR. One patient had fractures only seen by CT. CT was better than CXR in detecting rib fractures at every position along the ribs except for the lateral position. CT was particularly useful in detecting anterior rib fractures, an area that may be difficult to assess on CXR due to the often bulbous normal costochondral junction. Early subacute, subacute, and old fractures were better detected by CT. A major disadvantage to CT technology, however, is the significant radiation dose of CT compared with CXR. Strict attention to ALARA principles (Frush, 2002) minimizes this exposure, but children are more radiosensitive than adults, and the potential risk of CT-induced malignancy in the pediatric population has been widely publicized. Thus, CT must remain an important but selective tool in the evaluation of infants for nonaccidental trauma. The twelve abused infants involved in this study had rib fractures, and had received both CXR and CT assessments (eight abdomen CTs and four chest CTs). CT exams had been performed for clinical indication and were obtained within 1 day of the CXR. Studies were reviewed by two pediatric radiologists in order to determine the number, locations, and approximate ages of the rib fractures. A total of 225 ribs were completely (n=192) or partially (n=33) seen by CT, and the matched ribs on CXR were used for the analysis. 3 tables, 2 figures, and 29 references