If the technique chart calls for 12 mAs but the technologist uses 1.5 mAs on a portable radiograph, the resulting image will likely demonstrate which of the following?

If the technique chart calls for 12 mAs but the technologist uses 1.5 mAs on a portable radiograph, the resulting image will likely demonstrate which of the following?

• A. Saturation artifact
• B. Quantum mottle
• C. Loss of contrast
• D. No visible errors

Answer: (B)

When the mAs is far lower than the chart calls for, there aren’t enough photons reaching the detector to form a clean image. The random arrival of the limited photons creates statistical fluctuations that appear as graininess in the radiograph—this is quantum mottle. The image will look noisy, especially in uniform areas, and detail can be obscured. Saturation artifact would come from too much exposure, not too little, so that isn’t the issue here. Loss of contrast can occur with underexposure but the most characteristic and expected finding with a drastic underexposure is the grainy, mottled appearance of quantum mottle. No visible errors would imply a flawless image, which isn’t the case with underexposure.

When the mAs is far lower than the chart calls for, there aren’t enough photons reaching the detector to form a clean image. The random arrival of the limited photons creates statistical fluctuations that appear as graininess in the radiograph—this is quantum mottle. The image will look noisy, especially in uniform areas, and detail can be obscured.

Saturation artifact would come from too much exposure, not too little, so that isn’t the issue here. Loss of contrast can occur with underexposure but the most characteristic and expected finding with a drastic underexposure is the grainy, mottled appearance of quantum mottle. No visible errors would imply a flawless image, which isn’t the case with underexposure.