Abdominal Imaging
Cases
Case 1A 69 year old female presents to the ED with a 3 day history of worsening abdominal pain and distension.
Exam revealed distension, tympani, and volunteering guarding, but no rebound pain or signs of peritonitis.
An X-ray was ordered
Case 1
Lateral Chest X-ray – The spleen (*) can be seen outlined by the lucency created by the pocket of air
Frontal Chest X-ray – Extensive air can be seen under the diaphragm. The arrow points to gallbladder that is also surrounded by air
Pneumoperitoneum- Presence of air in the peritoneum cavity. It is most often caused by perforation of an abdominal viscus (i.e. a perforated ulcer).
Case 1
Unlike in the previous films pneumoperitoneum is usually more subtle and can be easily overlooked.
To the right you can see a plain radiograph of the right upper quadrant that shows a small streak of air under the diaphragm (white arrow).
Case 1CT scans are a great tool for visualizing pneumo-peritoneum. When the patient is supine, anteriorly placed gas can be differentiated from gas in the bowels.
CT can also detect extravasation of inflammatory fluid into the abdomen sometimes making localization of the perforation possible.
Case 1 In Pneumoperitoneum sometimes the Rigler Sign can be observed. It basically is when lucency from gas can be observed on both sides of the intestine.
Green Arrows – Air at the intra-luminal sideWhite Arrows – Air at the extra-luminal side
White arrows – Points to the intestinal wall that is surround on both sides by air
Case 1 The Football sign is seen in the setting of massive pneumo- peritoneum. It is where the abdomen is outlined by gas from a perforated viscus.
In the image to the right the falciform ligament can be seen overlying the vertebra (Long straight arrows). This is often included as a feature of the football sign. At left- the falciform ligament can be seen, but it is to the side of the spine (orange arrow)
Case 2The patient is a 58 year old male who presents with bilous vomiting and poorly localized abdominal pain that has been progressing over last 24 hours.
4 months ago the patient had a laparotomy for appendicitis.
Exam: Abdominal distension, and hyperactive bowel sounds
Plain abdominal X-ray was ordered. (notice the multiple distended loops of small bowel)
Case 2
Small bowel obstruction (SBO) is seen most commonly in patients who develop adhesions after previous surgeries.
In pediatric patients think of intussusception, Meckel’s diverticulum, or an incarcerated hernia.
On X-ray look for dilated loops of bowel (white arrows) and air fluid levels (orange arrows)
Case 2
CT is a useful test in guiding therapy. It can help answer:
- Is there an obstruction?
- Where is the transition point (obstruction)?
-Cause of the obstruction?
-Associated complications?
The above CT shows dilated loops of small bowel (white arrows). Notice that the colon is collapsed (red arrow). This is consistent with a mechanical small bowel obstruction.
Case 365 year old female presents with gradually worsening abdominal pain, constipation, and today had an episode of foul smelling vomit.
On exam he had a distended abdomen, tenderness with palpation, and quiet bowel sounds.
Abdominal X-rays were ordered (again, notice the dilated loops of bowel)
Large bowel Obstruction (LBO) – Like SBO proximal bowel is often dilated (white arrow) with air fluid levels (orange arrows).
In an adult the most common causes are: Diverticulitis, colon cancer, and a volvulus.
Case 3
Large bowel Obstruction:
- Like in SBO gases and feces tend to accumulate proximal to the obstruction.
- In longstanding LBO, muscular exhaustion can result in the effacement of haustra.
- The Cecum (*) generally dilates more than any other section of large bowel.
-Dilation > 10cm indicates possible perforation
Case 3
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Case 3Large bowel Obstruction
The Coffee Bean Sign – Name given to the radiologic appearance of a sigmoid volulus.
This CT shows dilated loops of both small bowel (white arrow) and large bowel (red arrow)
Case 3Large Bowel Obstruction
Case 4A 22 year old male that presents with intermittent abdominal pain.
The physical reveals RLQ abdominal pain
The CT to the right was ordered.
Case 4
CT Abdomen reveals a dilated appendix with a thickened wall (white arrow)
CT abdomen of another patient. The hyperdensity is an appendicolith (white arrow). Notice the fat stranding surrounding the appendix.
Acute Appendicitis
Case 4 Acute Appendicitis
A psoas abscess is a complication of acute appendicitis (*).
Notice the areas of inflammation over the psoas muscles (p).
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Case 4 Acute Appendicitis
Ultrasound is a great tool in detecting acute appendicitis in children and pregnant women. It is an operator dependent exam.
These two US scans show the same inflamed appendix (long arrow). Notice the hyper-echoic peri-appendiceal tissue surrounding the gallbladder, this is inflamation.
Case 4 Acute Appendicitis
Notice the hyper-echoic mass in the center of the inflamed appendix.
This appendicolith (*), has echogenic shadowing.
*
Case 5A 48 year old male presented to his primary care provider with a low grade intermittent fever and occasional episodes of bloody diarrhea.
Physical exam was negative, except for heme positive stool.
The patient was evaluated with a barium enema exam. Notice the loss of haustral folds in the descending colon (white arrows)
Case 5This is another radiograph from the same patient. Notice how featureless the sigmoid colon is. This is a classic representation of lead pipe bowel seen in chronic ulcerative colitis.
This typically only effects the left side of the colon in UC.
Inflammatory bowel disease- Ulcerative Colitis
Case 5
Pseudo polyps- are where the islands of hyperplastic mucosa protrude from a background of ulceration. This give the appearance of a polyp.
Inflammatory bowel disease- Ulcerative Colitis
Case 5This is a non-contrast CT in a patient with active Crohn’s Disease.
Notice the prominence of the mesenteric vasculature in this acute inflammatory process. This is called the Comb Sign.(Orange Arrows)
Inflammatory bowel disease- Crohn’s Disease
Case 5In longstanding Crohn’s Fistulas can sometimes develop.
An Ileo-ileo fistula can be seen in the coronal CT to the right (Arrow Heads)
Inflammatory bowel disease- Crohn’s Disease
Case 5
In the above CT, active inflammation due to crohn’s disease can be seen. This manifests as thickened bowel walls, mesenteric fat stranding, and mesenteric adenopathy.
Inflammatory bowel disease- Crohn’s Disease
Case 5Crohn’s vs Ulcerative Colitis Characteristic Crohn’s Disease Ulcerative ColitisSite of Origin Distal Ileum, proximal colon Rectum
Thickness of Pathology
Transmural Mucosa and submucosa only
Progression Irregular (skip lesions) Proximal, continuous from the rectum, no skipped areas
Location From mouth to anus Involves colon and rectum, rarely extends to ileum
Change in Bowel Habit
Obstruction, adb. Pain Bloody Diarrhea
Classic Lesions Fistula, abscesses, cobble- stoning, string sign, comb sign
Pseudopolyps, lead pipe colon, toxic mega-colon
Colon Cancer Risk Slightly increased Markedly increased
Surgery Cures Bowel disease
No (can worsen it) Yes (proctocolectomy with ileoanal anastomosis)
Case 6A 60 year old man presents with abdominal and back pain that radiates down his right leg.
Physical exam: Pulsitile mass R>>L
The following abdominal X-ray was taken.
Case 6Abdominal Aortic Aneurysm (AAA)
The bulging infra renal aneurysm is in red.
Case 6
This is the CT from the same patient seen in the previous slide.
Abdominal Aortic Aneurysm (AAA)
Abdominal Aortic Aneurysm (AAA)
Ultrasound can be a good screening to for AAA. It’s sensitivity is competitive to both MRI and CT.
Case 6
Case 6 Abdominal Aortic Aneurysm (AAA)
Aortography can be used to assess the aneurysm.
One drawback to this technique is that it tends to underestimate the aneurysm size. Due to it only show the patent vessel lumen.
Case 6 Abdominal Aortic Aneurysm (AAA)
Endovascular grafts can be used to repair the AAA and prevent eventual rupture.
Case 6 Abdominal Aortic Aneurysm (AAA)
In this aortogram the implanted graft can be seen in the lumen of the aorta.
Case 7A 68 year old man presents with abdominal pain. PMH: Hepatitis B.
Physical exam: Markedly enlarged Spleen
The following CT was performed. Notice the nodular appearance of the liver and enlarged spleen (*).
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Case 7This patient is suffering from Cirrhosis.
This image is of the same patient just on the coronal plane.
Cirrhosis.
Case 7
This image is also of the same patient. This slice is from the superficial abdominal wall.
Notice the multiple enlarge peri-umbilical vessels, this is know as caput medusa (white arrows).
Cirrhosis.
Case 8
A 79 year old male with PMH of prostate cancer, who present with abdominal pain.
The following CT was performed.
Case 8
This patient prostate cancer had spread to his liver.
The high vascularity of the liver makes it a common location for cancer to metastasize to.
Metastatic liver disease
Case 8 Metastatic liver disease
Metastatic Colon Cancer
Case 8 Metastatic liver disease
Metastatic Colon CancerWith central calcifications
Case 8 Metastatic liver disease
MRI of metastatic uterine leio-myosarcoma
Notice the ring enhancing lesion
Case 8 Metastatic liver disease
A B C
The above three images is from a 58 year old female with a large met from breast cancer. (A) CT showing the large metastisis in the left lobe of the liver. (red circle) (B) Shows the radio frequency ablation probe and it’s position at the tumor site. (C) Follow up CT showing tumor necrosis and shrinkage.
Case 9
An 26 year old female patient in the ER after Ped vs Car.
The patients vitals are stable.
The following CT scan was performed. Notice the irregular appearance of the spleen (*).
*
Case 9The patient issuffering from a splenic laceration.
Splenic lacerationCase 9
Interventional radiologist have a variety of option to reduce bleeding in splenic lacerations. The end result is the same, clotting off the artery to prevent distal bleeding. (A) Splenic arteriogram, revealing multiple aneurisms in the upper pole (arrows). (B) Arteriogram after ablation of upper pole. Notice that the lower poles vasculature is still intact (arrows)
A B
Case 10A 38 year old patient present with left flank paint and cloudy urine that sometimes has a red tinge.
Physical Exam: WNL
The following X-Ray was taken.
Case 10
The patient has a large calculus in the right kidney pelvis. (red circle)
The patient also has a smaller stone at the ureterovesicular junction. (white arrow)
Obstructive ureteral calculus
Case 10
The same patient had the following CT. (A) Notice the large calculus in the R. renal pelvis. Also, Notice the significant hydronephrosis in the L. Renal pelvis. (B) Notice the stone in the L. distal ureter, no doubt causing the proximal hydronephrosis.
Obstructive ureteral calculus
A B