What is the effect of filtration on receptor exposure?

What is the effect of filtration on receptor exposure?

• A. Greatly reduces receptor exposure because of the absorption of short-wavelength x-rays
• B. Greatly reduces radiographic receptor exposure because of the absorption of high-energy x-rays
• C. Increases radiographic receptor exposure by removing long-wavelength x-rays
• D. Has little effect on receptor exposure because x-rays removed from beam are not image-producing rays

Answer: (D)

Filtration removes the soft, low-energy portion of the X-ray spectrum before it reaches the patient. Those low-energy photons are mostly absorbed by superficial tissues and contribute little to the image at the receptor. By filtering them out, the beam becomes harder and the patient’s dose decreases, while the photons that actually reach the image receptor—our image-forming photons—are not significantly reduced. Therefore receptor exposure remains essentially unchanged; if image exposure were to fall, you’d adjust technique, but the main effect of filtration is dose reduction with little impact on image exposure.

Filtration removes the soft, low-energy portion of the X-ray spectrum before it reaches the patient. Those low-energy photons are mostly absorbed by superficial tissues and contribute little to the image at the receptor. By filtering them out, the beam becomes harder and the patient’s dose decreases, while the photons that actually reach the image receptor—our image-forming photons—are not significantly reduced. Therefore receptor exposure remains essentially unchanged; if image exposure were to fall, you’d adjust technique, but the main effect of filtration is dose reduction with little impact on image exposure.