CT Abdomen and Pelvis - Hollow Viscus

It's weird how you get runs of patients in the ED.  Some days it seems like it's nothing but wall-to-wall low risk chest pain, altered mental status, or back pain.  Today (and a lot of other days), it's abdominal pain.  Scanning the board you see seemingly nothing but Level 3 acuity patients with the chief complain of "Abdominal pain."  Out of the scores of patient's, you seen so far, the last 3 worry you the most:

Natasha is a very pleasant 20 year old student from a local college.  She came in after having symptoms of right lower quadrant pain over the course of the past 8-12 hours.  She didn't recall any migratory symptoms but does endorse a lack of appetite, nauseousness, 2 episodes of vomiting (started after the pain), and steadily worsening pain.  On exam you find her to have pretty significant right lower quadrant tenderness to palpation with voluntary guarding without rebound tenderness. Her pelvic exam is benign.  She's not febrile in the ED but is a bit tachycardic.  You're left thinking that there's a significant possibility she has appendicitis. Having just gotten back from CT you pull up the images and see what you can make of it.

Bruce, the other patient you are worried about, is a 65 year old man who began having aching pain in his left lower quadrant over the course of the past several days.  Having had diverticiulitis before, he though he could wait it out and hoped that the symptoms would get better.  Unfortunately, his symptoms have only worsened.  The pain, initially aching now is stabbing 10/10 severity pain that is worse with any sort of movement.  Febrile in the ED to 103 and tachycardic to 110 with significant LLQ tenderness to palpation and involuntary guarding, you're worried he has a significant abscess or perforation as a complication of diverticulitis.  Returning from CT, you pull up his images to see what you can find.

Tony, the 3rd patient you were worried about is a 55 yo man who has had multiple previous abdominal surgeries.  He has a history of Crohn's disease that has been generally poorly controlled leading to multiple flares and several short segment bowel resections.  Over the past day he has had severe nausea, vomiting, belly pain along with absence of bowel movements.  An acute abdominal series showed some air-fluid levels, but no clear obstruction.  You pull up his CT, looking to see if he has a small bowel obstruction not seen on the plain film x-ray.