Region of interest (ROI) fluoroscopic techniques have the potential for improving image quality and reducing radiation doses. Materials for x-ray beam shaping filters for ROI fluoroscopy are evaluated using a computer simulation which determines their transmission and effect on radiographic image contrast. Also a design for a new 'non-hardening' scanning filter consisting of an array of strips of radiopaque material separated by radiolucent spacings is presented. The array is placed close to the x-ray focal spot and scanned or vibrated so as to blur the image of the strips. Also a new dose spreading strategy based upon ROI fluoroscopy is introduced and is shown to have the potential to eliminate the problem of high patient skin exposures common during interventional procedures. Finally, applications of ROI fluoroscopy to continuously variable zoom or micro fluoroscopy and to peripheral vascular interventional procedures using continuously variable ROI size and shape are considered.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.