Chapter 11 Flashcards

Which of the following is frequently a problem in diagnostic pediatric radiography?

Lack of availability of appropriate pediatric immobilization devices

Lack of cooperation of parents or guardian

Lack of appropriate individuals to assist in holding a pediatric patient during an exposure

Patient motion

When a pregnant patient must undergo a radiographic procedure, which of the following practices will minimize radiation exposure?

Selecting technical exposure factors that are appropriate for the part of the body to undergo radiography

Opening the x-ray beam collimator shutters as wide as possible to ensure complete coverage of the image receptor

Precisely collimating the radiographic beam to include only the anatomic area of interest and shielding the lower abdomen and pelvis when this area does not need to be included in the area to be irradiated

Both A and C

In fluoroscopy, the amount of radiation that a patient receives is usually estimated by measuring the radiation exposure rate at tabletop and multiplying this by the:

fluoroscopy time

distance between the fluoroscope and the patient

square of the distance between the fluoroscope and the patient

radiographic exposure factors

_________ are the sensing devices most often used to measure skin dose directly.

Thermoluminescent dosimeters

A sequence of aluminum equivalent filters of varying thicknesses

Lead-impregnated filters

Molybdenum and rhodium filters

Studies of groups such as the atomic bomb survivors of Hiroshima have shown that damage to the newborn is unlikely for doses below _____ rads.

100

60

30

20

Poorly processed images on radiographic film will:

continue to have archival quality

deteriorate over time

lose only a minimal amount of archival quality over a 10-year period

remain in their original condition

If a child is placed in a CT scanner and adult protocols are used, the child will receive:

the same dose as an adult

a lower dose than an adult

a higher dose than an adult

no radiation dose

Of the following radiologic procedures, which is (are) considered nonessential?

A chest x-ray on scheduled admission to the hospital

Lumbar spine x-rays as part of a preemployment physical examination

Whole-body multislice computed tomography (CT) screening

All of the above

In the event that a pregnant patient is inadvertently irradiated, the _____ should perform the calculations necessary to determine fetal dose.

radiographer performing the examination

imaging department manager

radiologic physicist

radiologist

The goal of the Alliance for Radiation Safety in Pediatric Imaging is to:

increase awareness of the need to reduce patient dose for pediatric patients

completely eliminate the use of CT imaging for all pediatric patients

completely eliminate the use of CT imaging for pediatric patients under 1 year of age

completely eliminate the use of CT imaging for pediatric patients between the ages of 3 and 4 years old

The genetically significant dose (GSD) for the population of the United States is about _____ mSv (_____ mrem).

1.00; 100

0.80; 80

0.40; 40

0.20; 20

Which of the following types of gonadal shielding provide the best protection for a male patient when anteroposterior, oblique, and lateral projections are obtained?

Flat contact shield containing 1 mm of lead

Shadow shield

Shaped contact shield containing 1 mm of lead

None of the above; gonadal shielding is unnecessary for male patients of any age

According to the American College of Radiology (ACR), abdominal radiologic examinations that have been requested after full consideration of the clinical status of a patient, including the possibility of pregnancy, need:

not to be postponed or selectively scheduled

to be postponed or selectively scheduled

to be postponed and scheduled at least 10 days after the start of the next menstrual period

to be postponed and scheduled 10 days before the end of the next menstrual period

Which of the following must always be the first step in protection of the reproductive organs?

Adequate and precise collimation of the radiographic beam to include only the anatomy of interest

Use of gonadal shielding

Use of a mobile protective shielding device

Use of digital imaging equipment rather than conventional equipment

Digital mammography units with the ability to enhance contrast with image gray-level manipulation offer:

improvement for patients with small breasts

improvement for patients with microcalcifications in small breasts

improvement for patients with dense breasts

poor quality images for patients with dense breasts and microcalcifications

Which of the following are considered to be benefits of a repeat analysis program?
1. There is increased awareness among staff and student radiographers of the need to produce optimal quality recorded images.
2. Radiographers generally become more careful in producing their images because they are aware that the images are being reviewed.
3. When the repeat analysis program identifies problems or concerns, in-service education programs covering these specific topics may be designed for imaging personnel.

1 only

2 only

3 only

1, 2, and 3

The radiation dose absorbed by an organ such as bone marrow:

can be accurately measured by a direct method

cannot be measured by a direct method; it can only be estimated

is negligible for all diagnostic radiography examinations

can only be measured to a small degree by a direct method

In a remote control fluoroscopic room where the x-ray tube is located above the patient, protective shielding should:

be placed over the patient

be placed under the patient

be placed along side of the patient

not be used

Specific area shielding may be selectively used during some x-ray procedures to protect which of the following?
1. Lens of the eye
2. Breast
3. Extremities

1 and 2 only

1 and 3 only

2 and 3 only

1, 2, and 3

Which of the following combinations of technical exposure factors and filtration reduces patient radiation dose during a radiographic examination?

Lower kVp, higher mAs, decreased filtration

Higher kVp, lower mAs, increased filtration

Higher kVp, higher mAs, decreased filtration

Lower kVp, lower mAs, increased filtration

Any image that must be performed more than once because of human or mechanical error during the production of the initial image is known as repeat image. What effect does repeat images have on the radiation dose received by the patient?

The patient receives no additional radiation dose.

The patient’s skin and possibly the gonads receive a double radiation dose.

The patient’s critical organs receive a radiation dose that is 10 times greater than the initial radiation dose.

The patient’s superficial tissues only receive a radiation dose that is 4 times as great as that of the original radiation dose.

Which of the following are some of the factors that should be considered when technical exposure factors are to be selected?
1. Mass per unit volume of tissue of the area of clinical interest
2. Effective atomic numbers and electron densities of the tissue involved
3. Type and quantity of filtration used

1 and 2 only

1 and 3 only

2 and 3 only

1, 2, and 3

When automatic exposure control (AEC) is not used, then to ensure uniform selection of technical x-ray exposure factors, efficient imaging departments:

have estimated technical exposure factors for all radiographic examinations

have the radiologist determine and set up all technical exposure factor charts

use technique charts borrowed from another imaging facility

use standardized technique charts for each x-ray unit

During mammography, axillary projections should be done only on request of the:

ordering physician

patient

radiologist

technologist performing the examination

Because most medical procedures result in fetal exposures:

greater than 100 rads, the risk of abnormality is large

greater than 50 rads, the risk of abnormality is large

less than 25 rads, the risk of abnormality is small

less than 1 rad, the risk of abnormality is small