Performance and Pitfalls of Diagnostic X-ray Sources: an Overview

Performance and reliability of medical X-ray sources for imaging humans are crucial from ethical, clinical and economic perspectives. This overview will treat the aspects to consider for investment of equipment for medical X-ray imaging. Recent X-ray tubes deliver enhanced reliability and unprecedented performance. But, metric for benchmarking has to change. Modern terms for product comparison still need to penetrate the market and to be implemented in practice. It is time to abandon heat units and comply with latest standards, which consider current technology. In view of the increasing number of interventional procedures and the risks associated with ionizing radiation, toxic contrast agents, and the potentially hazardous combination thereof, system reliability is of paramount importance. This paper will discuss tube life time aspects. The speed of scientific and industrial development of new diagnostic and therapeutic X-ray sources remains high. Still, system developers and clinicians suffer from gaps between aspirations and reality in day-to-day diagnostic routine. Xray sources are still limiting cutting-edge medical procedures. Undesired side-effects, wear and tear, limitations of the clinical work flow, costs, and undesired characteristics of the X-ray source must be further addressed. New applications and modalities, like spectral CT, and phase-contrast or dark-field imaging will impact the course of new developments of X-ray sources. High performance and flawless operation of the very special kind of vacuum electronics of X-ray tubes can only be safeguarded by quality manufacturing and highly skilled craftsmanship. Joint development of semiconductor and vacuum based electronics, i.e. X-ray generators and tubes, has proven key to success in the medical industry to guarantee a seamless match of the once separate devices. Thus, the terminology is expected to morph from X-ray tube and high-voltage generator to X-ray source segment. Keywords— X-ray tube, X-ray generator, tube failures, Xray tube metric, reliability.