Under which condition should gonadal shielding be used?

• A. The gonads lie within 5 cm of the primary beam
• B. The patient is of reproductive age
• C. Shielding will not interfere with the diagnosis
• D. Gonads lie more than 5 cm from the beam

Answer: (A)

Gonadal shielding is used to minimize radiation exposure to the reproductive organs when they would be irradiated by the primary X-ray beam. The condition to apply shielding is when the gonads lie within about 5 cm of the primary beam. In that situation, shielding can meaningfully reduce dose without compromising the diagnostic information. If the gonads are more than about 5 cm away from the beam, shielding offers little benefit and may even interfere with image quality. Shielding should also be avoided if placing it would obscure anatomy or degrade the study. While patient age and potential pregnancy are important considerations, the specific criterion tested here is proximity of the gonads to the beam.