['To estimate the sensitivity and specificity of emergency department (ED) ultrasound for the detection of solid organ injury following blunt abdominal trauma.', 'A prospective cohort study performed in the ED of an urban Level I trauma center on patients who sustained blunt abdominal trauma. Following initial standard trauma evaluation, patients underwent a secondary ultrasound examination performed specifically to identify injury to the liver or spleen, followed by computed tomography (CT) scan of the abdomen. Ultrasound examinations were performed by emergency medicine residents or attending physicians experienced in the use of ultrasound for detecting hemoperitoneum. Ultrasonographers prospectively determined the presence or absence of liver or spleen injury. CT findings were used as the criterion standard to evaluate the ultrasound results.', 'From July 1998 through June 1999, 152 patients underwent secondary ultrasound examination and CT. Of the 152 patients, nine (6%) had liver injuries and 10 (7%) had spleen injuries. Ultrasound correctly detected only one of the liver injuries for a sensitivity of 11% (95% CI: 0%-48%) and a specificity of 98% (95% CI: 94%-100%). Ultrasound correctly detected eight spleen injuries for a sensitivity of 80% (95% CI: 44%-98%) and a specificity of 99% (95% CI: 95%-100%).'] Is emergency Department Ultrasound a Sensitive Detector of Solid Organ Injury?