Study of Normal Appendix on Multidetector CT

Objective:To Study the appearance of normal appendix on multidetector row CT(MDCT) and to improve diagnosis of early appendiceal lesions. Methods:One hundred patients who were ruled out appendicitis,appendectomy and other appendiceal lesions by clinical criteria underwent abdomen MDCT scan with 0.6 mm or 1.2 mm collimation.The appendix was reconstructed by using multiplanar reformation(MPR) and curved planar reformation(CPR) techniques.The following CT findings were evaluated:appendiceal diameter,appendiceal wall thickness,maximum depth of the intraluminal appendiceal fluid,appendicolith,gas and periappendiceal appearance. Results:The appendix was clearly visualized in 95 of 100 patients with 95% of sensitivity. Appendiceal diameter was from 3 to 10 mm with mean diameter 6.3±1.1 mm. The appendiceal diameter more than 6 mm was seen in 52 cases. Appendiceal wall thickness was from 1 to 4mm with mean thickness 2.6±0.5 mm,and thickness more than 3 mm seen in 25 cases.The intraluminal fluid was found in 17 cases with maximum depth greater than 2.6 mm seen in 2 cases.The gas was found in lumen in 58 cases.The appendicolith and calcific appendiceal wall were identified in 22 and 14 cases respectively. Periappendiceal fat stranding was not seen in all cases. Conclusion:MDCT with MPR and CPR reconstructions can clearly demonstrate the structure of normal appendix. It contributes to the diagnosis of early appendiceal lesions.