Diagnostic Value of Enhanced Multidetector Helical CT in Gangrenous Appendicitis

Objective To improve diagnostic level of gangrenous appendicitis with multidetector helical CT. Methods Eighteen patients with gangrenous appendicitis were collected after confirmed by surgery and histopathological examination. CT findings were analyzed and compared with pathologic parameters. Results Appendical wall thickening were 10 cases(56%)and appendical wall thinning were 4 cases (22%),appendix was not visible in 4 cases(22%). Appendical wall had discontinuous enhancement after administration of intravenous contrast material in those with appendical wall thickening. Appendical wall had not enhancement in those with appendical wall thinning. Appendical wall had defect in 9 cases(50%)on unenhanced CT examination and in 13 cases(72%)on enhanced CT examination .Abscess around appendix or in peritoneo-pelvic cavity was present in 13 cases(72%). Extraluminal gas was present in 13 cases(72%). Appendicolith was present in 12 cases(67%)and located outside appendical lumen in 4 cases(22%). Conclusion No enhancement,discontinuous enhancement or wall defect of appendical wall is a direct sign of gangrenous appendicitis. Enhanced CT examination is valuable in finding earlier gangrenous appendicitis. Abscess around appendix or in peritoneo-pelvic cavity,extraluminal gas,appendicolith outside appendical lumen were specific signs of gangrenous appendicitis.