Imaging Flashcards
How is a sagittal picture taken?
nose points to the left of the screen (because the whole body is facing that way)
how is an axial picture taken?
looking up from the feet
how is a coronal picture taken?
looking at the patient’s face
how is an AP picture taken? a PA?
X-rays enter the front of the patient and exit out the back to the sensor
x-rays enter the back of the patient and exit out the front
what is correct positioning?
the spinous processes are midway between the two heads of the clavicles
In a (AP/PA) view, the heart is close to normal size. In a (AP/PA) view, the heart is larger than normal. What accounts for this difference?
PA, AP
In the AP view, the heart is further away from the sensor so it is magnified as opposed to in the PA view where the heart is quite close to the sensor.
what is the cardio-thoracic ratio?
<50% (pathology is suspected if higher)
*measure transverse diameter
what is the thin line seen to the right of a heart in an AP radiograph?
horizontal fissure of the right lung (two layers of pleura)
what is the standard tube to film distance? what is it for portable radiographs?
6 feet
40 inches
what is lucency on a radiograph?
an area more transparent to xrays but appears dark on the image. (ex. air pockets)
what is opacity on a radiograph?
an area that decreases in intensity, therefor looks white and bright on the image (ex. bone)
what is density on a radiograph?
an object that BLOCKS light on an xray
define a radiologic edge:
a boundary between two different densities such that the transition is sharp (ex. bone and soft tissue)
define a radiologic line:
a visible opacity that is contrasted against more lucent areas on BOTH sides (can be reversed) (ex. horixontal fissure)
what is a sillouette sign?
the loss of a normal anatomic border because the normal structure (or abnormal like a tumor! think sail sign!) of similar opacity is in the way.
what is horner syndrome?
extension of neoplasm into the sympathetic chain ganglia
what are the symptoms of horner’s syndrome?
ptosis, miosis and anhidrosis
the SVC and the lung share a line or edge? Why?
an edge. The SVC is filled with blood. The lung is filled with air.
the trachea and the lung share a line or edge? why?
A line. both are filled with air.
In an air bronchogram where is contrast injected? what does is allow you to see?
in the lung alveoli (makes it opaque)
allows you to see any fluid or soft-tissue surrounding the air-filled bronchus
fluid in the alveoli indicate what?
infection
pulmonary edema
what is the directoin of the posterior ribs? Anterior and lateral ribs are in what direction?
horizontal; diagonal
a coin in the trachea is in what plane on a radiograph? in the esophagus?
in the trachea: sagittal plane
in the esophagus: coronal plane (flat and facing you)
If you want to see all of the branches of the aorta? what view do you want to see?
a Left Anterior Oblique
If you want to see the esophagus in a barium swallow, what radiogrph view do you want?
a right anterior oblique
What is the space between the aorta and pulmonary artery?
the aorticopulmonary notch
what are the two places in the body where you will see air mixed with liquid contents?
in the stomach and the colon
where does the aorta usually break?
right where the ligamentum arteriosum attaches: between the end of the arch and the descending aorta