Doppler ultrasound accurately screens patients with appendicitis

Ultrasound (US) has been reported as a useful aid to increase the sensitivi ty and specificity of the diagnosis of appendicitis. To determine the accur acy of US, we performed a prospective study of patients evaluated in the em ergency department for acute appendicitis. US results of 125 consecutive pa tients over an 11-month period were correlated with operative and pathologi c findings and clinical follow-up. The appendix was visualized as a noncomp ressible structure in 19 patients, and 18 had appendicitis (95%). Ten of th e 12 patients with abnormal Doppler activity in the appendix had appendicit is (83%). Conversely, the appendix could not be visualized in 102 patients, and 100 did not have appendicitis (98%). One hundred five of the 113 patie nts (93%) with absent abnormal Doppler activity did not have appendicitis. Ninety-four of the 125 patients had neither visualization of the appendix n or abnormal activity, and 2 had appendicitis. The sensitivity of US for app endicitis was 90 per cent, and the specificity was 94 per cent. Visualizati on of the noncompressible appendix or abnormal Doppler activity strongly su ggests appendicitis. More importantly, the absence of both of these ultraso nographic findings defines a patient subset that may be safely discharged f rom the emergency department without admission.