Appendicitis

Appendicitis is most commonly diagnosed on CT of the abdomen and pelvis.

A non-contrast CT  is about 90% and with contrast (oral or IV) the sensitivity increases to around 97-98%.  CT also has a high specificity, around 94-95%.

There are many findings on CT which are suspicious for appendicitis and they include the following:

·         A fecalith

·         Stranding in the surrounding fat or periappendiceal fluid

·         Surrounding abscess or phlegmon

The classic finding for appendicitis seen on CT (A dilated thickened tubular appearing appendix, greater than 6mm, with inflammatory stranding) can be seen here on EMPACS:

(type in search term of “appendicitis”)

http://www.empacs.org/scripts/mainsearch.php

Additional images can be viewed here

http://www.meddean.luc.edu/lumen/MedEd/Radio/Nuc_med/Appendicitis/ctfindings.htm

Linda Regan, MD FACEP

Program Director, Emergency Medicine Residency

Johns Hopkins Medical Institutions