This invention relates generally to diagnostic imaging systems, and more particularly to x-ray fluoroscopy imaging systems.
Diagnostic imaging systems are used in many different applications. One type of diagnostic imaging system is an x-ray imaging system. Using an x-ray imaging system, x-ray fluoroscopy may be used to obtain real-time moving images of the internal structures of a patient using a fluoroscope. Fluoroscopy has many known uses in diagnostic and image-guided procedures, including general-purpose fluoroscopy, vascular imaging, etc. During some fluoroscopic imaging procedures a patient may have to be imaged a number of times to obtain images having diagnostically relevant information.
Moreover, in conventional fluoroscopy systems, the last frame of a fluoroscopy acquisition sequence is displayed on screen after radiation/exposure has been terminated. This feature is referred to as Last Image Hold (LIH). In these conventional systems, it is possible to save this last acquired fluoroscopy image frame as part of patient record. However, the image quality of the LIH is marginal for diagnostic purposes and/or including in patient record for future review.
Thus, because of the marginal and sometimes unacceptable image quality of fluoroscopy LIH for static image display, most radiologists acquire an additional/replacement high-dose radiography (RAD) exposure at the point (spatial/temporal) of interest. The RAD exposure provides improved image quality compared to a fluoroscopic LIH, for example, to record anatomical information, but with substantially higher dose. Additionally, accumulation of multiple RAD exposures may be needed and requires multiple repeats of the procedure due to the delay in transitioning from a user observation of the event under fluoroscopy to actual RAD exposure. Accordingly, the patient is exposed to additional radiation.
Accordingly, the typical image quality is poor for archiving fluoroscopic images as part of patient record. Also, the alternative approach of acquiring a RAD exposure to record anatomical information provides improved image quality, but typically requires higher dose.