kilovoltpiek

Kilovoltpiek (kilovolt peak, abbreviated kVp) is the maximum voltage applied to an X-ray tube during an exposure. It defines the theoretical highest energy of the X-ray photons produced and is a primary factor in beam quality and penetrating power. The kilovoltage is selected on the imaging system and expressed in kilovolts (kV). In systems powered by alternating current, the kVp represents the peak of the voltage waveform; many modern generators deliver a near-constant potential with low ripple.

The control of kilovoltage is separate from tube current (mA) and exposure time, which together determine the total X-ray dose and receptor exposure. Increasing kVp increases photon energy, reducing subject contrast and improving penetration, while typically allowing lower mAs for the same receptor exposure. Conversely, decreasing kVp increases contrast but may require higher mAs and can raise patient dose if exposure settings are not optimized.

Typical diagnostic radiography ranges from about 60 to 120 kVp, depending on body part and imaging task; CT commonly uses 80–140 kVp, while specialized mammography and dental imaging employ different, lower or higher settings. Kilovoltpiek values are subject to quality control, calibration, and protection standards to ensure image quality while minimizing dose.