Exam 10: Radiation Dose in Computed Tomography

What is/are the purpose(s) of the use of bowtie filters in computed tomography? I. shape the beam intensity II. produce a more uniform beam III. increase scan time

The overall goals of automatic tube current modulation are to: I. provide consistent image quality II. increase scan speed III. control dose to the patient

What is the easiest and probably the most accurate method used to report dose?

If the pitch increases, the dose:

The radiation quantity exposure refers to the concentration of radiation at a particular point on the patient.

Which technique factor determines the quantity of photons (dose) incident on the patient for the duration of the exposure?

Which factors affecting dose in computed tomography have a direct influence on image quality but no direct effect on radiation dose?

The computed tomography dose index was developed by the U.S. Food and Drug Administration.

What term refers to the automatic control of the milliamperage in two directions during data acquisition by specific technical procedures?

What dose-response model is a radiation risk model most favored by radiobiologists in estimating the risk of exposure in radiology?

Stochastic effects are those effects for which the probability of the effect occurring depends on the dose.

Radiation protection actions include: I. decrease exposure time II. increase distance III. increase shielding

The method suggested by the Center for Devices and Radiological Health for computed tomography dose measurement is the pencil ionization chamber.

What is the amount of energy absorbed per unit mass of material? I. rad II. absorbed dose III. radiation dose

What is the dose limit for radiation workers in the United States?

The measured radiation dose is inversely proportional to the number of detector rows.

What types of dosimeters have previously been used to measure dose in computed tomography? I. film dosimeter II. thermoluminescent dosimeter III. ionization chamber

What instrument is used to measure the charge removed from the ionization chamber?

Examples of stochastic effects include: I. cancer II. leukemia III. hereditary effects

What term is used to refer to the size and shape of the beam emanating from the x-ray tube and passing through the patient?