Which technical factors yield the greatest dose to the patient?

The selection of the first set of technical factors reflects the highest patient dose due to a combination of higher milliampere-seconds (mAs) and a lower kilovolt peak (kVp).

In radiologic procedures, the patient dose is primarily affected by the mAs, which represents the product of the tube current (mA) and exposure time (seconds). In this scenario, the first option has a higher mAs value (27 mAs, calculated as 300 mA multiplied by 0.09 seconds) compared to the others; this directly correlates with an increase in the number of photons produced, which subsequently delivers a greater dose to the patient.

Additionally, while kVp also contributes to image quality and penetration, in this case, the combination of lower kVp (70 kVp) with the higher mAs value further enhances the likelihood of increased absorption of radiation by the patient. Lower kVp can result in higher energy absorption in soft tissues, amplifying the patient dose.

The use of a larger cassette size (14 x 17 inch) in the first option allows for a broader exposure, which may also contribute to a higher overall dose, as more tissue may be irradiated compared to smaller cassettes