Surgical Radiology, C30 P183-190 Flashcards
CHEST
What defines a technically
adequate CXR?
P183
The film must be “RIPE”:
Rotation: Clavicular heads are
equidistant from the thoracic
spinous processes
Inspiration: Diaphragm is at or below
ribs 8–10 posteriorly and ribs 5–6
anteriorly
Penetration: Disk spaces are visible
but there is no bony detail of the
spine; bronchovascular structures
are seen through the heart
Exposure: Make sure all of the lung
fields are visibleCHEST
How should a CXR be read?
P184
Check the following:
Tubes and lines: Check placement
Patient data: Name, date, history
number
Orientation: Up/down, left-right
Technique: AP or PA, supine or
erect, decubitus
Trachea: Midline or deviated, caliber
Lungs: CHF, mass
Pulmonary vessels: Artery or vein
enlargement
Mediastinum: Aortic knob, nodes
Hila: Masses, lymphadenopathy
Heart: Transverse diameter should be
less than half the transthoracic
diameter
Pleura: Effusion, thickening,
pneumothorax
Bones: Fractures, lesions
Soft tissues: Periphery and below the
diaphragmCHEST
What CXR is better: P-A or A-P?
P184
P-A, less magnification of the heart (heart
is closer to the x-ray plate)
CHEST Classically, how much pleural fluid can the diaphragm hide on upright CXR? P184
It is said that the diaphragm can
overshadow up to 500 cc
CHEST How can CXR confirm that the last hole on a chest tube is in the pleural cavity? P184
Last hole is through the radiopaque line
on the chest tube; thus, look for the break
in the radiopaque line to be in the rib cage
CHEST How can a loculated pleural effusion be distinguished from a free-flowing pleural effusion? P184
Ipsilateral decubitus CXR; if fluid is not
loculated (or contained), it will layer out
CHEST
How do you recognize a
pneumothorax on CXR?
P184
Air without lung markings is seen outside
the white pleural line—best seen in the
apices on an upright CXR
CHEST What x-ray should be obtained before feeding via a nasogastric or nasoduodenal tube? P184
Low CXR to ensure the tube is in the GI
tract and not in the lung
CHEST
What C-spine views are used
to rule out bony injury?
P184
CT scan
CHEST
What is used to look for
ligamentous C-spine injury?
P185
Lateral flex and extension C-spine films,
MRI
CHEST What CXR findings may provide evidence of traumatic aortic injury? P185
Widened mediastinum 8 cm (most common) Apical pleural capping Loss of aortic knob Inferior displacement of left main bronchus; NG tube displaced to the right, tracheal deviation, hemothorax
CHEST
How should a CT scan be
read?
P185 (picture)
Cross section with the patient in supine
position looking up from the feet
ABDOMEN
How should an abdominal
x-ray (AXR) be read?
P185
Check the following:
Patient data: name, date, history
number
Orientation: up/down, left-right
Technique: A-P or P-A, supine or
erect, decubitus
Air: free air under diaphragm,
air-fluid levels
Gas dilatation (3, 6, 9 rule)
Borders: psoas shadow, preperitoneal
fat stripe
Mass: look for organomegaly, kidney
shadow
Stones/calcification: urinary, biliary,
fecalith
Stool
Tubes
Bones
Foreign bodiesABDOMEN How can you tell the difference between a small bowel obstruction (SBO) and an ileus? P186
In SBO there is a transition point (cut-off sign) between the distended proximal bowel and the distal bowel of normal caliber (may be gasless), whereas the bowel in ileus is diffusely distended
ABDOMEN
What is the significance of
an air-fluid level?
P186 (picture)
Seen in obstruction or ileus on an upright
x-ray; intraluminal bowel diameter
increases, allowing for separation of fluid
and gas
ABDOMEN What are the normal calibers of the small bowel, transverse colon, and cecum? P186
Use the “3, 6, 9 rule”:
Small bowel 6 cm
Cecum
ABDOMEN
What is the “rule of 3s” for
the small bowel?
P186
Bowel wall should be
ABDOMEN How can the small and large bowel be distinguished on AXR? P186
By the intraluminal folds: The small bowel plicae circulares are complete, whereas the plicae semilunares of the large bowel are only partially around the inner circumference of the lumen
