MCQ post 04 : Radiotherapy Quiz

Radiotherapy Quiz

1. What is the primary goal of using bolus material in radiotherapy?

a) To reduce the dose to the skin b) To increase the dose to the tumor near the surface c) To improve patient comfort during treatment d) To avoid hot spots in the treatment area

2. What is the maximum allowable margin for setup error in a stereotactic radiosurgery (SRS) procedure?

a) 1 mm b) 2 mm c) 3 mm d) 5 mm

3. In IMRT (Intensity-Modulated Radiation Therapy), how is the dose distribution typically controlled?

a) By varying the radiation source's intensity at different angles b) By using the bolus to change the treatment depth c) By employing multiple beams with constant intensity d) By utilizing a single rotational arc for dose delivery

4. Which of the following is true regarding the dose-volume histogram (DVH) in radiotherapy?

a) It represents the exact position of the tumor and surrounding organs b) It shows the distribution of dose within the target volume and organs at risk c) It can only be used in IMRT treatment planning d) It provides a direct measurement of tissue response to radiation

5. What is the primary advantage of proton therapy over conventional X-ray radiation therapy?

a) Proton therapy provides better patient comfort b) Proton therapy offers better precision with less scatter to healthy tissues c) Proton therapy is more cost-effective d) Proton therapy can treat tumors that X-ray cannot

6. The 4D CT imaging technique in radiotherapy is mainly used to account for which of the following?

a) Patient's breathing motion during treatment b) Tumor volume changes over time c) Organs' radiation resistance variations d) The skin's radiation tolerance levels

7. The "equivalent uniform dose" (EUD) is used in radiotherapy treatment planning primarily to assess what?

a) The total radiation dose absorbed by healthy tissue b) The biological effect of a non-uniform dose distribution c) The tumor’s tolerance to radiation therapy d) The average radiation dose delivered to the tumor

8. Which of the following is the most important factor in determining the clinical outcome of radiotherapy for head and neck cancers?

a) The total dose delivered to the tumor b) The dose delivered to the tumor and surrounding organs at risk (OARs) c) The type of radiation therapy used d) The patient’s age and overall health status

9. In adaptive radiotherapy, what is the primary goal of re-planning during treatment?

a) To adjust for anatomical changes during treatment (e.g., tumor shrinkage, weight loss) b) To change the type of radiation from photons to protons c) To decrease treatment time d) To increase the dose delivered to critical structures

10. What is the role of a thermoplastic mask in patient immobilization during radiotherapy?

a) To reduce motion artifacts during imaging b) To ensure the patient is perfectly positioned and avoid movement during treatment c) To limit the amount of radiation exposure to the patient’s skin d) To provide a visual guide for tumor localization during the treatment