MODEL FOR PERCEPTION OF PULSED FLUOROSCOPY IMAGE SEQUENCES

Pulsed fluoroscopy at reduced frame rates can be used to lower x-ray d ose with equivalent detection (hereafter called equivalent perception) of low-contrast, stationary objects. Experimentally average dose savi ngs of 22%, 38%, and 49%, for pulsed fluoroscopy at 15, 10, and 7.5 ac quisitions per second, respectively, are documented. Dose savings depe nd on object size, with fewer savings for smaller objects. To explain these data, we extend the framework of an ideal observer with three mo dels for the spatiotemporal response of the human visual They are mode l 1, separable; model 2, nonseparable; and model 3, nonseparable with internal With no free parameters, model 1 predicts the average dose sa vings within a 3% difference but does not describe the effect of objec t size. Models 2 and 3 explain the influence of size, and model 3, wit h a single free parameter, fits the measurements best. Perception of p ulsed fluoroscopy is thus well described in terms of spatiotemporal pr ocessing by the HVS.