盲腸（C：Cecum）は図１４で盲端になり，図４から回腸末端（TI：Terminal Ileum）が始まり尾側へ下行する．図８の１と図９の２では虫垂根部で糞石（虫垂結石）が嵌頓し，図８の３〜図１２の８が約1cm大に，低吸収域の内容物で腫大した虫垂である．壁は強く造影され，図４〜図１２で周囲脂肪組織の濃度上昇を示しており（△），急性虫垂炎である．図A：切除標本，病理：phlegmonous appendicitis．

参考症例（5mmスライス，急性虫垂炎）：32歳女性．7時間前に心窩部痛が出現し，次第に右下腹部に移行した．体温：37.7℃，右下腹部に強い圧痛を認めるが反跳痛や筋性防御はない．

盲腸（C）は図８で盲端になり，回腸末端（ＴＩ）は図１から始まり下降する．図７と図８で虫垂根部に嵌頓した糞石（↑）があり，図７の1〜図１８の12が1cm以上に腫大した虫垂である．図８から先端までガスを含み，図１８の12で盲端になる．壁の造影効果は強くないが，図７〜図１０で腹膜の肥厚または脂肪組織の濃度上昇（△）を認め急性虫垂炎である．手術および病理所見（図A）：phlegmonous appendicitis．

文献考察３）：経静脈的enhanceによる急性虫垂炎のCT所見.
Acta Radiol. 2003 Nov;44(6):574-82.
The most useful findings for diagnosing acute appendicitis on contrast-enhanced helical CT.
Choi D, Park H, Lee YR, Kook SH, Kim SK, Kwag HJ, Chung EC.

PURPOSE: To evaluate the most useful findings to look for in diagnosing acute appendicitis on contrast-enhanced helical CT. MATERIAL AND METHODS: Appendiceal helical CT scans with intravenous contrast administration (abdomen, 7-mm collimation; abdominopelvic junction, 5-mm collimation) of 71 patients with surgically proven acute appendicitis and 167 patients with alternative diagnoses were reviewed retrospectively. Three radiologists analyzed the following parameters: enlarged appendix (>6 mm in diameter), appendiceal wall thickening, appendiceal wall enhancement, no identification of the appendix, appendicolith(s), appendiceal intraluminal air, intramural air, extraluminal air, periappendiceal fat stranding, extraluminal fluid, phlegmon, abscess, lymphadenopathy, segmental terminal ileal wall thickening, focal cecal apical thickening, focal colonic wall thickening, and segmental colonic wall thickening. The features that best distinguished appendicitis from alternative diagnoses were selected with stepwise logistic regression analysis. RESULTS: Nine CT findings distinguished acute appendicitis from alternative diagnoses (P enlarged appendix, appendiceal wall thickening, periappendiceal fat stranding, and appendiceal wall enhancement were the most useful findings for diagnosing acute appendicitis. PMID: 14616200