Figure 1b. Acute appendicitis in a 23-year-old woman,
31 weeks pregnant, who presented with acute RLQ pain. The appendix could
not be identified at US performed earlier in the day. Axial single-shot
fast SE images show a dilated appendix containing intraluminal fluid and
gas (arrows). The intraluminal ovoid low-signal-intensity filling defect
(arrowhead in b) is consistent with an appendicolith. Acute
appendicitis was confirmed at surgery. C = cecum, F =
fetus. (See also Figs E1 and E2 at http://radiographics.rsnajnls.org/cgi/content/full/27/3/743/DC1.)