KUMJ | VOL. 14 | NO. 4 | ISSUE 56 | OCT.-DEC. 2016
Multi-Detector Computed Tomography Evaluation of Normal Appendix
Suwal S, Karki S, Mandal D, Poudel RC
Abstract: Background
Appendix is a blind-ended tubular structure arising from caecum, with variable
intraluminal contents and position. Acute appendicitis is one of the common
indications for emergency radiological investigation.
Objective
To assess visualization rate, size and position of normal appendix by Computed
Tomography (CT).
Method
This cross-sectional observational study was done in 198 individuals undergoing
abdominal CT without suspicion of acute appendicitis and without any pathology
localized within right iliac fossa. Axial and coronal reformatted images of nonenhanced
and contrast enhanced CT of abdomen were evaluated for visualization of
appendix. Visualized appendices arising from caecum were traced and tip localized.
Contents within the appendicular lumen were also evaluated and maximum
transverse diameter of appendix measured. The relationship between appendicular
diameter, intraluminal content and position with different age groups & gender were
also derived.
Result
Visualization rates of appendix were 90% (93% male and 87% female) in nonenhanced
CT and 97% (99.8% male and 95.4% female) in enhanced CT. The mean
diameter of the appendix was 6.2 ± 1.16 mm. Most common location of the tip
of appendix was pelvic position, followed by retrocaecal position. Most of the
appendices showed intraluminal air.
Conclusion
Multi-Detector Computed Tomography is superior over ultrasonography (USG) in
detection of appendix. Modifications of CT protocol reduce limitations of CT over
ultrasound in evaluation of appendix. Ultrasound size criteria for appendicitis (>6
mm) is not applicable in CT as normal appendix can measure >6 mm in CT.
Keyword : Diameter, location, normal appendix, multi-detector computed tomography