Interpretations of abdominal X-Rays Flashcards
How to confirm patient details on AXR?
- Name
- Hospital Number
- DOB
- Date and time of X-ray
- Establish whether previous imaging is available
How to assess the image type?
- Assess projection of image
- Anterior-posterior (supine)
- Anterior-Posterior (erect)
- Exposure•Is the whole abdomen visible? (Diaphragm to pelvis)
- Are you able to see small bowel/large bowel?
What is this?
Normal AXR
Explain the interpretation of AXR
- Structured approach (BBC)
Bowel (and other organs – SB, LB, Lungs, Liver, GB, Stomach, psoas, Kidney, spleen, Bladder)
Bones (Ribs, vertebrae, sacrum, coccyx, pelvis)
Calcification (eg renal stones, Gallstones, aorta)•
What is the difference between the small bowel and large bowel?
- Distribution (SB usually lies centrally, with the large bowel ‘framing’ it)
- SB mucosal folds (Valvulae conniventes) – visible across full width of bowel
- Large bowel wall features haustra (thicker than valvulae conniventes and typically does not appear to traverse the width of the bowel)
- Faeces (mottled appearance in large bowel, due to air trapping in solid faeces)
What is circled in the AXR?
Faeces
What are the different diameters of the bowel?
- Upper limits
- Small bowel (3cm)
- Colon (6cm)
- Caecum (9cm)
What are the features of small bowel obstruction?
- Features:
- Dilatation of small bowel (>3cms)
- Prominent valvulae conniventes
What are the causes of small bowel obstruction?
- Causes:
- Adhesions (75%)
- Abdominal hernias
- Intrinsic/extrinsic compression (eg tumours)
What is this?
Small bowel obstruction
What are under-exposed AXR’s look like?
Lighter → harder to read
What does an over-exposed AXR look like?
Darker
What is this?
Gallstone ileus
What are the causes of large bowel obstruction?
Causes:
- Colorectal Cancer
- Diverticular stricture
- Hernia
- Volvulus
What is this?
Large bowel obstruction
What is this?
Sigmoid volvulus
What is the characteristic appearance of sigmoid volvulus?
Sigmoid volvulus:
a characteristic ‘coffee bean’ appearance
What is this?
Sigmoid volvulus
What is this?
Rigler’s sign
What is Rigler’s sign?
In healthy individuals, only the inner wall of the bowel should be visible on an abdominal X-ray. The presence of free air within the abdomen (pneumoperitoneum) can result in both sides of the bowel wall becoming visible (this is known as Rigler’s sign)
What is this?
Perforation (free air under the diaphragm)
What does a perforation cause?
Free air under the diaphragm
What are some inflammatory bowel diseases & their features?
- Crohn’s disease
- Ulcerative colitis
- Thumbprinting
- Lead-pipe (featureless) colon
- Toxic megacolon
What is thumbprinting?
Thumbprinting: mucosal thickening of the haustra due to inflammation and oedema causing them to appear like thumbprints projecting into the lumen.
What is lead-pipe (featureless) colon?
Lead-pipe (featureless) colon: loss of normal haustral markings secondary to chronic colitis.
What is a toxic megalocolon?
Toxic megacolon: colonic dilatation without obstruction associated with colitis.
What is this?
Ulcerative colitis showing ‘lead piping’
What is this?
Thumb-printing in ulcerative colitis
What are some other organs to see on AXR (or look out for)?
- Lungs: inspect the lung bases for pathology (e.g. consolidation) as abdominal pain can, in some cases, be caused by basal pneumonia.
- Liver: a large right upper quadrant structure.
- Gallbladder: rarely visible on an abdominal X-ray, however, you should quickly inspect for calcified gallstones and cholecystectomy clips.
- Stomach: visible between the left upper quadrant and midline, containing a variable amount of air.
- Psoas muscles: the lateral edge is marked by a relatively straight line either side of the lumbar vertebrae and sacrum.
- Kidneys: both are often visible, the right kidney is lower than the left due to the presence of the liver on the right.
- Spleen: located in the left upper quadrant, superior to the left kidney.
- Bladder: has a variable appearance depending on the fullness of the bladder.
What bony structures can be seen on an AXR?
- Bony structures commonly visible on abdominal X-ray include:
- Ribs
- Lumbar vertebrae
- Sacrum
- Coccyx
- Pelvis
- Proximal femurs
How can bony metastasis be seen on AXR?
- From prostate cancer can be seen as either more white on AXR or sometimes more dark
What can be seen as high density (white) areas on AXR?
- Various high density (white) areas of calcification or artefact may be noted on abdominal X-ray including:
- Calcified gallstones in the right upper quadrant
- Renal stones/staghorn calculi
- Pancreatic calcification
- Vascular calcification
- Costochondral calcification
- Contrast (e.g. following a barium meal)
- Surgical clips
- Jewellery
What is this?
Renal stent
What is this?
Renal stone
What is this?
Belly-button piercing
What is this?
Adhesions - small bowel dilation
