Positioning of Chest and Positioning Situations/Errors Flashcards
why is a PA chest preferred to an AP projection?
reduces magnification of heart
Why should a left lateral be performed unless departmental protocol indicates otherwise?
better demonstrates the heart region
The CR is placed at what level of vertebra for a PA chest projection?
T7
How much separation of the posterior ribs on a lateral chest projection indicates excessive rotation from a true lateral position?
0.5 to 0.75 inch
To prevent the clavicles from obscuring the apices on an AP projection of the chest, the CR should be angled __________ so that it is perpendicular to the ___________.
caudad; sternum
What position would be used if a patient were unable to stand but the physician suspected that the patient had fluid in the left lung?
left lateral decubitus
What specific position would be used if the patient were unable to stand but the physician suspected that the patient had free air in the left pleural cavity?
right lateral decubitus
What circumstances or clinical indications suggest that an AP lordotic projection should be ordered?
rule out calcifications beneath the clavicles
What position/projection would be used for a patient who is too ill or weak to stand for an AP lordotic projection?
AP semiaxial projection, CR 15-20 degrees cephalad
Which anterior oblique projection would best elongate the left thorax?
RAO
Which posterior oblique would best elongate the left thorax?
LPO
For certain studies of the heart, which oblique projection requires a rotation of 60 degrees?
LAO
Where is the CR placed for a lateral projection of the upper airway?
C6 or C7, midway between thyroid cartilage and jugular notch
Careful collimation during a chest radiograph will improve image quality by decreasing what to the IR?
scatter radiation
What is the recommended patient instruction when performing an erect PA chest on a female patient with large breasts?
lift breast up and outward then remove hands as she leans against IR to keep in position
T/F: No lead shielding is necessary for male patients or women older than age 65 during radiographic imaging of the chest.
false
An erect chest PA radiograph aids the patient to achieve full inspiration and helps to prevent __________________ and ________________ of the pulmonary vessels.
engorgement; hyperemia
T/F: a grid is not recommended for an LPO projection of the adult chest.
false
A radiograph of a PA view of the chest shows that the sternoclavicular (SC) joints are not the same distance from the spine. The right SC joint is closer to the midline than the left SC joint. What is the positioning error?
rotation
patient is slightly rotated into an RAO position
A radiograph of a PA projection of the chest demonstrates only 7 posterior ribs above the diaphragm. What caused this problem and how could it be prevented on the repeat exposures?
lungs are underinflated
take exposure on the 2nd inspiration
A radiograph of a PA projection of the chest demonstrates the top of the apices is cut off and a wide collimation border can be seen below the diaphragm. How can this be corrected during the repeat radiograph?
make sure CR is lined up with T7 vertebra and that the IR is centered with the CR
A patient comes for a presurgical chest examination. The clinical history indicates a possible situs inversus of the thorax (transposition of structures within thorax). Which positioning action must be taken to perform a successful examination?
make sure the correct anatomic marker is placed correctly
A radiograph of a lateral projection of the chest shows the posterior ribs and costophrenic angles are separated more than 1” or 2.5 cm, indicating excessive rotation. Describe a possible method for determining the direction of rotation.
determine which hemidiaphragm is more posterior or anterior
A patient enters the emergency room with a possible hemothorax in the right lung caused by a MVA. The patient is unable to stand or sit erect. Which specific projection would best demonstrate this condition, and why?
right lateral decubitus bc the side of interest should be down
A young child enters ER with a possible foreign body in one of the bronchi of the lung. The peanut cannot be seen on the PA and lateral projections. Which additional projection(s) could the technologist perform to locate the foreign body?
AP and lateral upper airway
A routine chest series indicates a possible mass beneath the patient’s right clavicle. PA and lateral are in conclusive. What additional could be taken?
AP lordotic
PA and left lateral projections demonstrate a suspicious region in the left lung. The radiologist orders an oblique projection that will best demonstrate the left thorax. Which specific oblique projections will best elongate the left thorax?
LPO and RAO
