The Accuracy of Ultrasound Diagnosis of Appendicitis: An Audit

Abstract

The outcome of 100 consecutive patients between July 2002 and January 2003 referred for ultrasound examinations with suspected appendicitis were audited. Patients were scanned using a high frequency probe with standard compression techniques over the right iliac fossa. Ultrasound diagnosis of appendicitis was made if a tubular, non-peristaltic and non-compressive blind ending structure measuring over 6 mm in diameter was seen. In predominantly paediatric patients, the additional findings of echogenic surrounding mesentery and abdominal collections were also noted. Follow-up was in the form of retrieving notes to determine whether the patient had gone to theatre and had confirmed appendicitis at histopathology. Sixty per cent of patients scanned had pathology, 30% of which had a bowel mass seen on ultrasound. Of this 30%, 79% were confirmed as appendicitis at theatre. However, 40% of patients scanned had no abnormality seen on ultrasound and 28% of these subsequently went to theatre. Thirty-six per cent of these had confirmed appendicitis at theatre.