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  • Section 4 Radiation Induced Cataracts

  • Section 4 Radiation Induced Cataracts Questions

    1. A 25-year-old woman undergoes cerebral angiography and a CT scan of the brain involving 2-mm-thick sections that include the orbits. What is the patient’s estimated lifetime risk probability for radiation-induced cataracts?

    A. 0%
    B. 0.01%
    C. 0.1%
    D. 1.0%
    E. 10.0%

    2. Which of the following statements best characterizes radiation-induced cataracts?
    A. Cataracts begin in the anterior portion of the lens.
    B. A dose of 1 Gy over 5 years is likely to produce a cataract.
    C. Prescription eyeglasses protect from 80% of the dose to the lens from diagnostic x–rays.
    D. Vision-impairing cataracts are preceded by asymptomatic opacities in the lens.

    3. Which of the following statements concerning radiation-induced cataracts are true? (Select all that apply.)
    A. A cataract is a stochastic effect.
    B. The minimum single acute dose of x rays that will produce a cataract is 2 Gy.
    C. A single dose of radiation is more likely to induce a cataract than the same amount of radiation administered in 10 fractions.
    D. For a given dose, neutrons are more effective than gamma rays in producing cataracts.

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