A radiograph of an RAO sternum is superimposed over the thoracic spine. Which specific positioning error is visible on the radiograph?
Under rotation of the patient.
A radiograph of an RAO sternum reveals that the sternum is difficult to visualize because of excessive density. The following analog exposure factors were used for this image: 100 kV, 25 mA, 3-second exposure, 40" (100 cm) SID, and Bucky. Which one of these factors should be modified during the repeated exposure to produce a more diagnostic image?
Lower the kV to 65 for higher contrast and to prevent overpenetration of the sternum
A radiograph of an RAO sternum reveals that the sternum is poorly visualized because of excessive lung markings superimposed over the sternum. The following analog exposure factors were used for this image: 75 kV, 200 mA, 1-second exposure, 40" (100 cm) SID, and bucky. Which of these factors can be altered to increase the visibility of the sternum?
Increase the exposure time (and lower the mA) to allow for greater blurring of the lung markings
A radiograph of a lateral projection of the sternum reveals that the patient's breasts are obscuring the sternum. What can be done to minimize the breast artifact over the sternum?
Have the patient bring the breasts to the side; hold them in this position with a wide bandage
Repeat PA projections of the SC joint do not clearly demonstrate them. What other imaging modality may produce a more diagnostic image of these joints?
Computed Tomography (CT)
SITUATION: A patient with trauma to the sternum and the left SC joint region enters the emergency room. In addition to the sternum routine, the ER physician asks for a specific projection to better demonstrate the left SC joint. Describe the positioning routine that you would use, including the breathing instructions.
10 to 20 degrees RAO sternum with (Orthostatic breathing technique) lateral sternum on inspiration; and 10 to 15 degrees LAO of SC joint with suspended inspiration
A radiograph of the upper ribs demonstrates that the diaphragm is superimposed over the 7-8 ribs, which is in the area of interest. The following analog exposure factors were used for the initial exposure: 75 kV, 400 mA, 1/40 second, suspended respiration on expiration, erect position, 40" (100 cm) SID. Which one of these factors can be modified to increase the visibility of the area of interest?
Suspend respiration during inspiration to move the diaphragm below the eighth ribs
SITUATION: A patient enters the ER on a backboard after being involved in an MVA. Because of the condition of the patient, the physician orders a portable study of the sternum in the ER. What projections of the sternum would be most diagnostic yet minimize movement of the patient.
LPO and horizontal beam lateral projections*may use 15 to 20 degree mediolateral central angle if patient cannot be in oblique position
SITUATION: A patient with trauma to the right upper anterior ribs enters the ER. He is able to sit in an erect position. Which positioning routine of the ribs should be performed?
Erect PA and LAO or RPO position with suspended inspiration
SITUATION: A patient with trauma to the left lower anterior ribs enters the ER. Which positioning routine of the ribs should be performed?
Recumbent PA (or AP if patient cannot be prone) and RAO or LPO positions with suspended expiration
SITUATION: An elderly patient comes to the radiology department for a complete rib series with an emphasis on the posterior ribs. She has advanced osteoporosis and has difficulty moving and lying down. Her physician wants both upper and lower ribs examined. What type of positions should be performed? How would you adjust technical factors for this patient?
Because of patient condition, it is best to perform all positions erect and initiate exposure on full inspiration for upper ribs and full expiration for lower ribs. AP projections and both posterior obliques must be performed. It is recommended that kV (manual technique employed) for all projections be lowered because of the advanced osteoporosis.
SITUATION: A patient enters the ER with blunt trauma to the chest. He is restricted on a backboard. The ER physician suspects flail chest. Beyond the initial chest projection, what positioning routine would confirm the diagnosis of flail chest?
A limited rib series will indicate which ribs are fractured (and where this has led to the trauma). Because the patient is restricted to a backboard, the oblique position may not be possible.