Which of the following is NOT related to spatial resolution?

Spatial resolution in imaging refers to the ability to distinguish two separate points in an image. Factors that influence spatial resolution include focal spot size, source-to-object distance (SOD), and object-to-image distance (OID).

Focal spot size directly affects spatial resolution because a smaller focal spot produces sharper images, allowing for better detail and distinction between closely spaced objects. The source-to-object distance also plays a critical role; as this distance increases, the amount of geometric blur decreases, thereby improving spatial resolution. Similarly, OID impacts the resolution because an increased distance between the object and the image receptor can lead to magnification and decrease sharpness, thus reducing resolution.

In contrast, milliamperage is primarily related to image contrast and dose rather than spatial resolution. It influences the quantity of x-ray photons produced but does not directly impact the ability to resolve fine details in the image. Therefore, the correct answer is that milliamperage is NOT related to spatial resolution.