Surgery>>>>>The Appendix
Question 2#

What imaging finding would exclude appendicitis?

A. A computed tomographic (CT) scan with a nonvisualized appendix
B. A barium enema where a short (2 cm) appendix was clearly identified
C. An ultrasound study with a compressible appendix that is <5 mm in diameter
D. A CT scan showing an edematous but retrocecal appendix

Correct Answer is C

Comment:

Graded compression ultrasonography is inexpensive and rapid. The appendix is identified as a nonperistaltic, blind ending loop of bowel. The compressibility and anteroposterior dimensions are measured. Thickening of the wall as well as peri-appendiceal fluid with a noncompressible appendix are suggestive of appendicitis while an easily compressible, narrow appendix excludes the diagnosis. Failure to identify the appendix on imaging does not definitely rule out appendicitis. A fecalith in the mid appendix may allow proximal filling of the appendix with barium in the presence of appendicitis. Sonographic sensitivity for appendicitis is 55 to 96% while specificity is 85 to 98%.